A Navajo family practices social distancing and mask-wearing during the coronavirus pandemic. Image Credit: Getty Images

<p>According to CDC data, Indigenous people are getting vaccinated quicker than any other group. Here are the successes—and challenges—of getting vaccines to urban Native American communities.</p>

American Indians have the highest Covid vaccination rate in the US

Rex J. Walheim waves at the camera during a spacewalk in 2002. NASA built 18 suits with interchangeable parts in 1974 for the space shuttle program. Over the years, many of the suits have broken down or been destroyed in launch or reentry disasters. Today, only a few complete, functioning suits remain, having far outlived their 15-year design life. Image Credit: NASA Johnson, Flickr

<p data-block-key="aaw0f">An engineer-artist duo wants to create sleeker spacesuits that meet the challenges of a low-pressure environment while offering more mobility—and looking cool.</p>

<p data-block-key="ix906">An engineer-artist duo wants to create sleeker spacesuits that meet the challenges of a low-pressure environment while offering more mobility—and looking cool.</p>

A spacesuit designer on what to wear to the moon

Stanley Andrisse holds an MBA and Ph.D. His nonprofit organization From Prison Cells to PhD offers education counseling, mentoring, and support to 100+ currently and formerly incarcerated people annually. Image Credit: Tchad at Free Star Media

<p>New programs aim to help formerly incarcerated people enter careers in science, technology, engineering, and mathematics.</p>

Meet the scientists building a prison-to-STEM pipeline

Koch Foundation

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<p data-block-key="4wm05">NOVA Next is NOVA’s award-winning digital publication that provides answers from the cutting edge of science and technology. Launched in 2012, we feature in-depth articles and commentaries from some of the most respected journalists, scientists, and engineers. NOVA Next explores the ideas that are changing the future, from the frontiers of synthetic biology to the politics of personalized medicine.</p><p data-block-key="6689y">Let us know what you think. We’re listening on <a href="http://www.facebook.com/NOVAonline">Facebook</a>, <a href="http://twitter.com/novapbs">Twitter</a>, and email.</p><p data-block-key="izhuv">If you’re a journalist and have an idea for a story, send it our way.</p>

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<p data-block-key="wa4xx">NOVA Next is NOVA’s award-winning digital publication that provides answers from the cutting edge of science and technology.</p>





  
      <p data-block-key="3nb29">Scientists just added 301 exoplanets to an already confirmed cohort of more than 4,000 worlds outside our solar system.</p><p data-block-key="c4gdj">Most exoplanets known to scientists have been discovered by NASA’s Kepler spacecraft, which was retired in October 2018 after nine years of collecting data from deep space. Kepler, which as of its retirement had discovered more than 2,600 exoplanets, “revealed our night sky to be filled with billions of hidden planets—more planets even than stars,” NASA reports <a href="https://www.nasa.gov/kepler/presskit">in a press release</a>. Kepler would look for temporary dimness in the stars it was observing, a sign that a planet may be moving in front of it from the spacecraft’s perspective. The easiest planets to detect have been <a href="https://www.pbs.org/wgbh/nova/article/potential-exoplanet-discovered-outside-milky-way-galaxy/">gas giants</a> like Saturn and Jupiter. But scientists have also been able to use data from Kepler to identify <a href="https://www.pbs.org/wgbh/nova/article/the-most-earth-like-planet-yet-found/">Earth-like planets</a> in the habitable zone, an area around a star that’s neither too hot nor too cold for liquid water to exist on a planet.</p>
  

  
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      <p data-block-key="3nb29">The challenge scientists have historically faced is a time-related one: “For missions like Kepler, with thousands of stars in its field of view, each holding the possibility to host multiple potential exoplanets, it&#x27;s a hugely time-consuming task to pore over massive datasets,” NASA reported on November 22 <a href="https://www.nasa.gov/feature/ames/new-deep-learning-method-adds-301-planets-to-keplers-total-count">in a press release</a>. So, when it came to identifying the latest 301 exoplanets, researchers based at NASA’s Ames Research Center in Mountain View, California, turned to a new deep neural network called ExoMiner. </p><p data-block-key="eu9r9">Now, <a href="https://arxiv.org/pdf/2111.10009.pdf">in a paper</a> accepted for publication in The Astrophysical Journal, the team describes how, analyzing data from NASA’s Pleiades supercomputer, ExoMiner was able to identify planets outside our solar system. It did so by parsing through data from Kepler and the spacecraft’s second mission K2, distinguishing “real exoplanets from different types of imposters, or ‘false positives,’” NASA reports. </p><p data-block-key="1mvmj">The Kepler Science Operations Center pipeline originally identified the 301 exoplanets, which were then promoted to planet candidates by the Kepler Science Office before being officially confirmed as exoplanets by ExoMiner, NASA reports. </p><p data-block-key="7jibh">ExoMiner “is a so-called neural network, a type of artificial intelligence algorithm that can learn and improve its abilities when fed a sufficient amount of data,” Tereza Pultarova <a href="https://www.space.com/artificial-intelligence-300-exoplanets-in-kepler-data">writes for Space.com</a>. Its technology is based on exoplanet-identification techniques used by scientists. To test its accuracy, the team gave ExoMiner a test set of exoplanets and potential false positives, and it successfully retrieved 93.6% of all exoplanets. The neural network “is considered more reliable than existing machine classifiers” and, given human biases and error, “human experts combined,” Marcia Sekhose <a href="https://www.businessinsider.in/science/space/news/exominer-machine-learning-method-helped-discover-301-exoplanets/articleshow/87979847.cms">writes for Business Insider India</a>. </p><p data-block-key="jtaa">&quot;When ExoMiner says something is a planet, you can be sure it&#x27;s a planet,&quot; ExoMiner Project Lead Hamed Valizadegan told NASA.</p>
  

  
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      <p data-block-key="3nb29">But the neural network does have some limitations. It “sometimes fails to adequately utilize diagnostic tests,” including a centroid test, which identifies large changes in a center of a star as an object passes by it, the researchers report in the paper. And at the time of the study, ExoMiner did not have the data required to decode “flux contamination,” a measurement of contaminants coming from a source. (In the hunt for exoplanets, flux contamination often refers to the light of a star in the background or foreground of a target star interfering with data coming from the target star.) Finally, ExoMiner and other data-driven models using visible light to detect exoplanets cannot correctly classify giant exoplanets orbiting orange dwarf stars. But these giant planet candidates are incredibly rare in Kepler data, the researchers report.</p><p data-block-key="59l19">Because they exist outside the habitable zones of their stars, Pultarova writes, none of the 301 exoplanets identified by ExoMiner are likely to host life. But soon, scientists will use ExoMiner to tackle data from other exoplanet hunters, including NASA’s <a href="https://www.pbs.org/wgbh/nova/article/star-explodes-supernova-hubble-tess/">Transiting Exoplanet Survey Satellite</a> (TESS). Unlike Kepler, which surveyed star systems 600 to 3,000 light-years away before running out of fuel, TESS, which launched six months before Kepler’s end, documents stars and their exoplanets within <a href="https://heasarc.gsfc.nasa.gov/docs/tess/objectives.html#:~:text=The%20TESS%20Mission%20is%20designed,within%20~200%20light%20years).">200 light-years</a> from Earth. These nearby exoplanets are the ripest for <a href="https://www.pbs.org/wgbh/nova/article/nasas-tess-spacecraft-will-scan-the-sky-for-exoplanets/">scientific exploration</a>, scientists believe.</p><p data-block-key="ajo6i">“With a little fine-tuning,” the NASA Ames team can transfer ExoMiner’s learnings from Kepler and K2 to other missions like TESS, Valizadegan told NASA. “There’s room to grow,” he said.</p>
  

  
      

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First Earth-like planet detected by Kepler

An artist's concept of exoplanet Kepler-186f. Discovered by Kepler in 2014, Kepler-186f is the first validated Earth-size planet to orbit a distant star in the habitable zone. Image Credit: NASA/JPL

<p data-block-key="uz46d">NASA scientists used a neural network called ExoMiner to examine data from Kepler, increasing the total tally of confirmed exoplanets in the universe.</p>

Deep learning tool helps NASA discover 301 exoplanets





  
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      <p data-block-key="6q7n1">For 10 days in 1995, the Hubble Space Telescope turned its gaze toward a small and seemingly empty patch of space. The result was the “<a href="https://hubblesite.org/contents/articles/hubble-deep-fields?keyword=deep%20field">Hubble Deep Field</a>,” a very-much-not-empty image packed with the 3,000 faintest galaxies ever detected.</p><p data-block-key="6d7aq">Hubble has been at the center of such remarkable discoveries for more than 30 years, detecting the atmospheric makeup of exoplanets, using light wavelengths to help us understand how stars form, and giving humanity its first ringside seat <a href="https://www.pbs.org/wgbh/nova/article/star-explodes-supernova-hubble-tess/">at a supernova</a>. </p><p data-block-key="ddvpd">Building on Hubble’s science, NASA is now preparing to launch its successor: the James Webb Space Telescope (JWST). The telescope (whose name has <a href="https://www.nature.com/articles/d41586-021-02678-1">sparked controversy</a>) will be able to look even further into the past by going beyond visible light and observing primarily in the infrared part of the spectrum. As the universe expands, light emitted by the first luminous objects has been stretched out, or “redshifted” into longer wavelengths. The JWST is designed to pick up these wavelengths with sensitivity and resolution so powerful it will be able to observe light arriving from only a few hundred million years after the Big Bang. </p><p data-block-key="83map">Still, for decades our best views of the universe came from Hubble. Here’s a look back at some of the spectacular images that helped us better understand our universe.</p>
  

  
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            <figure class="richtext-image full-width">
            <img alt="Large red nebula and small blue nebula in space" class="richtext-image full-width" height="549" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/image_QB7DqH3.width-800.png"/>
            <figcaption><p data-block-key="q3vkf">The image was taken by Hubble&#x27;s Wide Field Camera 3 to commemorate Hubble&#x27;s 30 years in space in 2020. Image Credit: NASA, ESA, and STScI</p><div class="credit"></div></figcaption>
            </figure>
            <h3 data-block-key="cnm5a"><b>&quot;Cosmic Reef&quot;</b></h3><p data-block-key="e51lf">This giant red nebula and its smaller blue neighbor are part of a vast star-forming region in the Large Magellanic Cloud, a satellite galaxy of the Milky Way, some 163,000 light-years away. The image is nicknamed &quot;Cosmic Reef,&quot; NASA says, because the red nebula resembles a coral reef floating in a sea of stars. The sparkling central region is a group of hefty stars, each 10 to 20 times more massive than our sun.</p>
            <figure class="richtext-image full-width">
            <img alt="Two galaxies overlapping" class="richtext-image full-width" height="604" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/STScI-01EVT416RRVAS0Q6F20ZB56K0P.width-800.jpg"/>
            <figcaption><p data-block-key="k4kv5">A 2012 composite of separate exposures. Image Credit: NASA, ESA, the Hubble Heritage Team (STScI/AURA)-ESA/Hubble Collaboration, and W. Keel (University of Alabama)</p><div class="credit"></div></figcaption>
            </figure>
            <h3 data-block-key="npcg"><b>Overlapping Galaxies</b></h3><p data-block-key="28dgj">A rare view of a pair of overlapping galaxies, called NGC 3314. The two galaxies look as if they are colliding, but they&#x27;re actually separated by tens of millions of light-years, or about ten times the distance between our Milky Way and the neighboring Andromeda galaxy, NASA says. Despite their appearance here, the motion of the two galaxies indicates that they are both relatively undisturbed and are moving in markedly different directions—not on any collision course.</p>
            <figure class="richtext-image full-width">
            <img alt="Cluster of bright starts amid wispy gas in space" class="richtext-image full-width" height="793" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/image_wXK9GRv.width-800.png"/>
            <figcaption><p data-block-key="6huki">A 2016 image from an imaging and spectroscopic study of the region. Image Credit: NASA, ESA, and P. Crowther (University of Sheffield)</p><div class="credit"></div></figcaption>
            </figure>
            <h3 data-block-key="afr3s"><b>Star Cluster R136</b></h3><p data-block-key="3dksb">In the central region of the Tarantula Nebula, some 170,000 light-years from Earth, lies a dense cluster of young stars (seen at the lower right). Among the hundreds of young, blue stars are the most massive stars detected in the universe so far, NASA says. In the most dense, central region of this cluster astronomers have found nine stars with masses greater than 100 times the mass of our sun.</p>
            <figure class="richtext-image full-width">
            <img alt="Pink, yellow, and blue streams of gas in space" class="richtext-image full-width" height="384" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/image.width-800.png"/>
            <figcaption><p data-block-key="w5ppw">A 2015 image was created with observations taken by Hubble&#x27;s Wide Field Camera 3 instrument using five different filters to enhance the contrast of the Veil Nebula’s gases. Image Credit: NASA and STScI</p><div class="credit"></div></figcaption>
            </figure>
            <h3 data-block-key="3la5p"><b>Veil Nebula</b></h3><p data-block-key="dtiqr">A small section of the Veil Nebula, the debris of a supernova remnant formed roughly 8,000 years ago by the death of a star 20 times the mass of our sun. As massive stars tend to do, it “lived fast and died young,” ending its life in a cataclysmic release of energy. The shockwaves and debris from that supernova sculpted the Veil Nebula’s delicate wisps of ionized gas. In this image, red corresponds to hydrogen, green to sulfur, and blue to oxygen.</p><p data-block-key="8n4sr"></p>
            <figure class="richtext-image full-width">
            <img alt="Bright red start in halo of brown dust" class="richtext-image full-width" height="800" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/image_IhhDVlI.width-800.png"/>
            <figcaption><p data-block-key="ezgqf">A 2002 image. Image Credit: NASA, ESA and H.E. Bond (STScI)</p><div class="credit"></div></figcaption>
            </figure>
            <h3 data-block-key="8vven"><b>Light Echo from a Red Supergiant Star</b></h3><p data-block-key="aim41">This image of the red supergiant star V838 Monocerotis reveals dramatic changes in the illumination of its surrounding dust clouds. The effect, called a light echo, unveiled never-before-seen dust patterns when the star suddenly brightened in January 2002. It temporarily became one of the brightest stars in the Milky Way—600,000 times brighter than our sun—before fading in April 2002. In contrast to a normal nova explosion, V838 Monocerotis did not expel its outer layers, NASA reported. Instead, it ballooned in size, and its surface temperature dropped to temperatures not much hotter than a light bulb. Scientists aren’t sure why it erupted this way but say the outburst may represent a rarely seen transitional stage in a star&#x27;s evolution.</p>
  

  
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            <figure class="richtext-image full-width">
            <img alt="A vertical jet of gas shoots from a cloud" class="richtext-image full-width" height="947" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/STScI-01EVT22TSX47VX9ZD9XEMED0N8.width-800.jpg"/>
            <figcaption><p data-block-key="0knw0">A 2015 composite of separate exposures. Image Credit: NASA and ESA</p><div class="credit"></div></figcaption>
            </figure>
            <h3 data-block-key="ance9"><b>Herbig-Haro Object 24</b></h3><p data-block-key="cqs1l">Newly formed stars sometimes shoot out thin, hot jets of ionized gas, creating a lightsaber-like effect known as a Herbig-Haro object. The young star obscured by dust at the center of this image lies in our own Milky Way, some 1,350 light-years away. Hubble observed this HH object in infrared; according to NASA, these young stellar jets will be ideal targets for the JWST, which will have even greater infrared wavelength vision to see deeper into the dust surrounding newly forming stars.</p>
            <figure class="richtext-image full-width">
            <img alt="Pink formation in space like butterfly wings" class="richtext-image full-width" height="780" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/STScI-01EVT5J2YNC48M6KA3ENRQCD6F.width-800.jpg"/>
            <figcaption><p data-block-key="zs012">A 2009 composite image captured by Hubble&#x27;s Wide Field Camera 3 in ultraviolet and visible light. Filters isolated emissions from oxygen, helium, hydrogen, nitrogen, and sulfur from the planetary nebula. Image Credit: NASA, ESA, and the Hubble SM4 ERO Team</p><div class="credit"></div></figcaption>
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            <h3 data-block-key="e09fs"><b>Butterfly Nebula</b></h3><p data-block-key="841uk">As smaller stars die, they eject their outer layers of gas into space over the course of about 10,000 years, leaving behind a hot core known as a white dwarf. Radiation from the white dwarf at the center of this image illuminates the departing gas, creating a striking formation called a planetary nebula. According to <a href="https://hubblesite.org/science/stars-and-nebulas">NASA</a>, the name comes from the early days of astronomy, when observers thought the dim forms they observed might be related to planets. With an estimated surface temperature of more than 400,000 degrees Fahrenheit, the central star of this planetary nebula is one of the hottest stars on record.</p>
            <figure class="richtext-image full-width">
            <img alt="Jupiter and its moon Europa" class="richtext-image full-width" height="692" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/STScI-01EVST3AQNE0JHHWA3MQCYRPVC.width-800.png"/>
            <figcaption><p data-block-key="i54gt">A 2020 composite of separate exposures. Image Credit: NASA, ESA, STScI, A. Simon (Goddard Space Flight Center), and M.H. Wong (University of California, Berkeley) and the OPAL team</p><div class="credit"></div></figcaption>
            </figure>
            <h3 data-block-key="335r7"><b>Jupiter and Europa</b></h3><p data-block-key="5hpd2">This fairly recent image of Jupiter captured not only the gas giant’s famed Great Red Spot, but a bright white, stretched-out storm in the mid-northern latitudes that’s traveling around the planet at 350 miles per hour. And below the Great Red Spot, Oval BA—nicknamed Red Spot Jr.—continues to fluctuate, now shifting from its typical whitish coloration to redder tones. The <a href="https://kera.pbslearningmedia.org/resource/nvfl.sci.space.europa/life-on-europa/">icy moon Europa</a>, which is thought to hold potential ingredients for life, is visible to the left of Jupiter.</p>
            <figure class="richtext-image full-width">
            <img alt="Colorful pillars of gas and dust in space" class="richtext-image full-width" height="736" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/image_rMNvRdv.width-800.png"/>
            <figcaption><p data-block-key="wf7gc">A 2010 composite of separate exposures. Image Credit: NASA, ESA, and M. Livio and the Hubble 20th Anniversary Team (STScI)</p><div class="credit"></div></figcaption>
            </figure>
            <h3 data-block-key="8bl3h"><b>&quot;Mystic Mountain&quot;</b></h3><p data-block-key="fdq5a">In the prolific stellar nursery known as the Carina Nebula, chaos unfolds at the top of a three-light-year-tall pillar of gas and dust. Scorching radiation and streams of charged particles from super-hot newborn stars in the nebula shape and compress the pillar, causing new stars to form within it. At the same time, the pillar is torn apart from within, NASA reports, as infant stars buried inside it fire off jets of gas that can be seen streaming from its peaks.</p>
            <figure class="richtext-image full-width">
            <img alt="Pink and white swirling galaxies" class="richtext-image full-width" height="683" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/STScI-01EVT7EAJG4YWW4JK4Z940SP38.width-800.jpg"/>
            <figcaption><p data-block-key="fhvyk">This 2006 image uses visible and near-infrared observations from Hubble’s Wide Field Camera 3, along with previous observations from Hubble’s Advanced Camera for Surveys. Image Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)-ESA/Hubble Collaboration</p><div class="credit"></div></figcaption>
            </figure>
            <h3 data-block-key="fosv"><b>Antennae Galaxies</b></h3><p data-block-key="ctj27">Hubble has been documenting the merging of two spiral galaxies dubbed the “Antennae galaxies” for years.The pair began to interact a few hundred million years ago, NASA reports, and during the course of the collision, billions of stars will be formed. This clash is so violent that stars have been ripped from their host galaxies to form a streaming arc between the two, the inspiration for their name. And the rate of star formation is so high that the Antennae galaxies are said to be in a state of starburst, a period in which all of the gas within the galaxies is being used to form stars. This stage cannot last forever and neither can the separate galaxies; eventually, they will meld together to become one large elliptical galaxy.</p>
  

  
      

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A 2006 composite image from NASA's Hubble Space Telescope and Spitzer Telescope shows the chaos of baby stars in the Orion nebula some 1,500 light-years away. Image Credit: NASA/JPL-Caltech/STScI

<p data-block-key="wk70g">With the upcoming launch of the James Webb Space Telescope, the Hubble era is gradually drawing to a close. Here are some highlights from the countless wonders Hubble has shown us during its 31 years in space.</p>

10 spectacular Hubble Space Telescope images





  
      <p data-block-key="hcqxj">Today at 1:21 a.m. EST, NASA launched its Double Asteroid Redirection Test (DART) spacecraft in the first-ever “full-scale planetary defense test” to deflect an asteroid, the Agency reports. The craft, built and operated by Johns Hopkins Applied Physics Lab in Laurel, Maryland, is designed to autonomously target and intentionally crash into—at 14,400 miles per hour—an asteroid.</p><p data-block-key="q6bk">The hope is that by hitting an asteroid destined to collide with Earth, a successor to DART could redirect it away from our planet, preventing impact.</p><p data-block-key="92iaj">“Planetary defense is about making sure that a rock from space doesn’t send us back to the Stone Age,” DART Program Scientist Tom Statler said <a href="https://svs.gsfc.nasa.gov/13985">in a NASA interview</a>. “And the key parts of planetary defense are, first of all, finding the asteroids that are potentially hazardous to the Earth. And we understand where about 40% of those asteroids are.”</p>
  

  
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      <p data-block-key="hcqxj">One of those space rocks is Bennu. In October 2020, more than 200 million miles from Earth, a NASA spacecraft named OSIRIS-REx <a href="https://www.pbs.org/wgbh/nova/article/osiris-rex-bennu-asteroid-touchdown/">reached out</a> and grabbed a sample from the spinning-top-shaped asteroid, as scientists believe it may contain <a href="https://www.pbs.org/wgbh/nova/video/inside-osiris-rexs-mission-to-tag-asteroid-bennu/">essential ingredients</a> to our solar system’s planetary formation. Bennu, which is slightly wider than the Empire State Building is tall, is slowly—and steadily—getting closer to Earth.</p><p data-block-key="4qor5">At a NASA news conference in August, scientists said that there’s a 1-in-1,750 chance that Bennu will collide with Earth between now and the year 2300, a slight increase from scientists’ previous estimate of 1-in-2,700. (Despite the “now” in this prediction, you and your children, and most likely your grandchildren, will be gone before there’s any possibility of this collision happening, Kenneth Chang <a href="https://www.nytimes.com/2021/08/11/science/asteroid-bennu-earth-osiris-rex.html">reports for the New York Times</a>.)</p><p data-block-key="91se4">Bennu isn’t alone. Though the chances of Earth getting hit by an asteroid like the one that <a href="https://www.pbs.org/wgbh/nova/video/fossil-discovery-could-offer-glimpse-into-day-the-dinos-died/">ended the era</a> of dinosaurs 66 million years ago are slim, fragments of asteroids, “from pebble-sized to person-sized,” hit Earth every day, <a href="https://svs.gsfc.nasa.gov/13985">NASA writes in a press release</a>. An asteroid larger than about 10 feet in diameter hits Earth about once every year, and there’s about a 1-in-50,000 chance of an asteroid larger than 3,200 feet across hitting Earth every 100 years, Bruce Betts <a href="https://www.planetary.org/articles/will-an-asteroid-hit-earth">reports for Planetary.org</a>. “This isn’t the sort of thing that we want to address at the last minute,” NASA program scientist Kelly Fast told NOVA in June.</p>
            <figure class="richtext-image full-width">
            <img alt="DART&amp;#x27;s November 2021 launch" class="richtext-image full-width" height="450" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/DART_Launch.width-800.jpg"/>
            <figcaption><p data-block-key="y16n8">Riding atop a SpaceX Falcon 9 rocket, DART took off Wednesday, November 24 from Space Launch Complex 4 East at Vandenberg Space Force Base in California. Image Credit: NASA/Bill Ingalls</p><div class="credit"></div></figcaption>
            </figure>
            <p data-block-key="7fvak">DART is headed to a binary asteroid system that will be within 6.8 million miles from Earth in September 2022. Its target is a 525-foot space rock named Dimorphos, meaning “two forms” in Greek, which orbits the half-mile-wide asteroid Didymos (meaning “twin”), NASA reports.</p><p data-block-key="9i5ak">Because Didymos and its moon come “pretty close to Earth,” Johns Hopkins Applied Physics Lab Systems Engineer Elena Adams told NOVA in June, it’s technically “considered a potentially hazardous” system. But, like Bennu, its chances of striking our planet are incredibly slim. “There’s nothing that we could do to it that will make it a danger to the Earth,” Statler said. Hitting Didymos’ moon Dimorphos, for example, won’t change the trajectory of Didymos, Adams told NOVA.</p>
  

  
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      <p data-block-key="hcqxj">DART will try to push Dimorphos using a technique called kinetic impact deflection: intentionally crashing into the space rock in a bid to move it. Approximately four hours before impact, DART will become fully autonomous, directing itself toward the tiny moon 60,000 miles away. The goal isn’t to simply move Dimorphos. “The important thing isn’t how far we move the asteroid,” Statler said. “It’s how much we change its speed by.” To determine whether the strike was successful at altering Dimorphos’ velocity, scientists will analyze any changes to its orbit with telescopes back on Earth.</p><p data-block-key="98j6t">Kinetic impact deflection is one potential method—and the “most technologically mature”—of a few proposed techniques to redirect an object hurtling in space, NASA reports. As NASA scientists continue to investigate asteroid deflection strategies, research teams across the globe aim to discover asteroids that could be potentially hazardous to our planet. Ideally, they’ll identify any space rock “on a collision course with Earth” years in advance, Statler said in a NASA interview, buying time for scientists to redirect its path. The goal is never to destroy an asteroid, Statler said: “We probably wouldn’t be able to do that anyway.”</p><p data-block-key="518fl">The chances of an asteroid large enough to cause damage to Earth, but small enough to avoid detection well in advance of its approach, are slim. But that doesn’t discredit DART’s mission, Statler suggested. “We take precautions about low-probability events all the time,” he said. If researchers do happen to spot a dangerous asteroid years in advance, “then a change to its velocity,” Statler said, “can make the difference between an impact on Earth and a safe miss.”</p>
  

  
      

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An illustration of the DART spacecraft approaching the binary asteroids Didymos and Dimorphos. Image Credit: NASA/Johns Hopkins APL

<p data-block-key="76aht">As the first-ever “full-scale planetary defense test” to deflect a space rock, the DART mission aims to show that protecting Earth from a hazardous asteroid is possible.</p>

NASA launches mission to redirect an asteroid—by striking it with a spacecraft





  
      <p data-block-key="jukty">Using observations from NASA’s Hubble Space Telescope and other space- and ground-based telescopes, an international team of astronomers and physicists has witnessed the death of a star by supernova in real time—about 60 million light-years away from Earth in the constellation Virgo. The team reported its findings in the journal<a href="https://academic.oup.com/mnras/advance-article-abstract/doi/10.1093/mnras/stab2887/6410679?redirectedFrom=fulltext"> Monthly Notices of the Royal Astronomical Society</a> on October 26.</p><p data-block-key="63lcv">Historically, astrophysicists and other scientists have analyzed supernovas after they occur. In fact, the first human record of one dates back <a href="https://www.scirp.org/journal/paperinformation.aspx?paperid=107638">to 185 CE</a>. “We used to talk about supernova work like we were crime scene investigators,” said astronomer Ryan Foley, who led the new research, in<a href="https://www.nasa.gov/feature/goddard/2021/hubble-gives-unprecedented-early-view-of-a-doomed-stars-destruction"> a NASA press release</a>. By making observations after the explosive event, scientists would try to figure out what happened to the star.</p>
  

  
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      <p data-block-key="jukty">Foley and study co-author Samaporn Tinyanont, both of the University of California, Santa Cruz, are calling the event, formally named SN 2020fqv, “The Rosetta Stone of supernovas” because it could help inform scientists when other stars in the universe are ready to explode.</p><p data-block-key="4ehnk">Massive stars—those much larger than our sun—explode as supernovas when they run out of fuel. During a star’s lifetime, its stable spherical shape results from the balance between heat and pressure generated by hydrogen fusion at its core, which push outward, and gravity, which pulls inward. As long as that balance is maintained, nuclear fusion can generate enough power to keep a star shining for billions of years.</p><p data-block-key="cr9ga">But all stars eventually run out of power. And when a star about eight or more times the mass of our sun runs out of nuclear fuel and the outward pressure of heat wanes, gravity wins. It begins to pull everything inward. The star’s core becomes denser and denser, collapsing faster and faster until a final massive crunch releases a surge of heat and energy—as hot as tens of billions of degrees. This causes the outer material of the star to explode as a supernova.</p><p data-block-key="8usts">“You know that saying ‘Live fast, die young’? That really applies to stars, right? So the most massive, luminous stars have the shortest lifetimes,” Harvard &amp; Smithsonian astrophysicist Grant Tremblay <a href="https://www.pbs.org/wgbh/nova/video/star-dies-supernova/">tells NOVA</a>.</p><p data-block-key="1o0pu">SN 2020fqv is in the interacting Butterfly galaxies, a place already watched by NASA’s Transiting Exoplanet Survey Satellite (TESS). “TESS provided an image of the system every 30 minutes starting several days before the explosion, through the explosion itself, and continuing for several weeks,” NASA states in its press release. On Mar. 31, 2020, the star that became SN 2020fqv began flaring up, Emily Conover<a href="https://www.sciencenews.org/article/supernova-explosion-2020fqv-tess-hubble"> reports for Science News</a>, eventually going supernova in April. TESS and researchers at the Zwicky Transient Facility at the Palomar Observatory in San Diego were watching. And since Hubble had been tracking the star for decades, the team was able to go back to Hubble’s observations from the 1990s onward.</p>
  

  
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      <p data-block-key="jukty">In the hours and days following the first observations of the supernova, the team coordinated “a last-minute change of plans for the Hubble Space Telescope,” Conover writes, which “provided the supernova’s spectrum, an accounting of its light broken up by wavelength, at various moments after the blast.” Mere hours after the supernova, Hubble made observations of the gas, dust, and other matter, called circumstellar material, around SN 2020fqv, George Dvorsky<a href="https://gizmodo.com/observations-of-exploding-star-in-real-time-deemed-a-1847916844"> reports for Gizmodo</a>.</p><p data-block-key="9c3f1">“We were able to make ultra-rapid observations with Hubble, giving unprecedented coverage of the region right next to the star that exploded,&quot; Tinyanont told NASA.</p><p data-block-key="fiqg7">By comparing its observations of the star with theoretical models, using historical data from Hubble, and “measuring the amount of oxygen in the supernova, which is a proxy for mass,” Elizabeth Howell<a href="https://www.space.com/doomed-star-rosetta-stone-of-supernovas-hubble-photo"> writes for Space.com</a>, the team was also able to calculate the mass of the star. The results of all three methods were consistent: The star was 14 to 15 times the mass of our sun, the researchers believe.</p><p data-block-key="e9deh">The team hopes the finding will do more than inform them of the star’s final years and moments. It could help astronomers predict when other stars in the universe are about to explode, they say.</p><p data-block-key="n79m">&quot;Now we have this whole story about what&#x27;s happening to the star in the years before it died, through the time of death, and then the aftermath of that,&quot; Foley told NASA. &quot;This is really the most detailed view of stars like this in their last moments and how they explode.&quot;</p>
  

  
      

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Astronomers watch supernova 60 million light-years away

Astronomers recently witnessed supernova SN 2020fqv explode inside the interacting Butterfly galaxies, located about 60 million light-years away in the constellation Virgo. Image Credit: NASA, ESA, Ryan Foley (UC Santa Cruz); Image Processing: Joseph DePasquale (STScI)

<p data-block-key="rz4g7">An international research team used Hubble, TESS, and other instruments to witness the “Rosetta Stone” of supernovas. Its findings could help astronomers predict when other stars in the universe are about to explode.</p>

Astronomers watch a star explode in real time





  
      <p data-block-key="931iz">At the 1998 Winter Olympics in Nagano, Japan, snowboarding made its debut as an Olympic sport. No longer relegated to the fringes, snowboarders took to the snow-capped peaks of Mount Yakebitai, and 26-year-old Canadian Ross Rebagliati rose to global fame. But shortly after he won gold in the giant slalom event, a drug test revealed <a href="https://deadspin.com/how-a-stoned-canadian-changed-sports-history-990167249">17.8 nanograms</a> per milliliter of THC, the psychoactive compound in cannabis, in Rebagliati’s system, which he still attributes to <a href="https://www.usatoday.com/story/sports/olympics/2013/07/17/ross-rebagliati-olympics-marijuana-drug-testing/2528283/">secondhand smoke</a>.</p><p data-block-key="jvmu">“Cannabis back then was seen as being for losers and lazy stoners,” Rebagliati told <a href="https://www.nytimes.com/2018/11/02/world/canada/canada-pot-snowboarder-olympics.html">The New York Times.</a> “The big corporate sponsors didn’t want to sponsor me. I became a source of entertainment, a joke. I went from hero to zero overnight.”</p><p data-block-key="437dc">Rebagliati was initially stripped of his medal, but because cannabis had not been <a href="https://www.washingtonpost.com/wp-srv/sports/longterm/olympics1998/sport/snowboard/articles/medal12.htm">officially banned</a> by the International Olympic Committee (IOC), he was ultimately able to keep the gold. Two months after his failed drug test, the <a href="https://www.deseret.com/1998/4/27/19376774/ioc-adds-marijuana-to-its-no-no-list">IOC officially banned cannabis</a> due to its illicit status as a social drug.</p>
  

  
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      <h3 data-block-key="zesoq"><b>The politicization of pot </b></h3><p data-block-key="a36lf">As the war on drugs was waged on America’s streets, it was also playing out in sports arenas around the world. “We had to draw a lesson from Nagano,” IOC Director General Francois Carrard told the <a href="https://www.deseret.com/1998/4/27/19376774/ioc-adds-marijuana-to-its-no-no-list">Associated Press</a> in 1998. “The IOC wants to take a stand against a social drug.&quot;</p><p data-block-key="e1fnn">Prince Alexandre de Merode, chairman of the IOC medical commission at the time, added that cannabis should be banned even though it <a href="https://www.deseret.com/1998/4/27/19376774/ioc-adds-marijuana-to-its-no-no-list">does not act as a performance-enhancer</a> like steroids.</p><p data-block-key="3t6he">Roger Pielke Jr., an expert in sports governance and a professor of environmental studies at the University of Colorado Boulder, claims that “the deeper reality was that the Clinton administration’s focus on anti-doping regulations helped serve its domestic policy agenda, which was focused on waging a war on drugs.”</p><p data-block-key="8q8fb">In 1998, the United States <a href="https://www.washingtonpost.com/sports/olympics/2021/07/03/shacarri-richardson-marijuana-olympics-doping-ban/">pledged an unprecedented $1 million</a> to assist the IOC in its mission to eradicate drugs from elite sports. Barry McCaffrey, director of the Office of National Drug Control Policy, was adamant that recreational drugs such as cannabis should be just as much of a priority for the international sports community as performance-enhancing drugs. </p><p data-block-key="6i08g">“We raise Olympic athletes up on international pedestals for all the world’s children to look up to as role models—it is vital that the message they send is drug-free,” McCaffrey wrote in a <a href="https://apnews.com/article/36e9c87e8521c6553ef208d390b2885c">10-page memo to the IOC</a>. “The goal of this whole effort must be to prevent Olympic medals and the Olympic movement from being tarnished by drugs.”</p>
            <figure class="richtext-image full-width">
            <img alt="Snowboarder passing slalom flag" class="richtext-image full-width" height="518" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/RossRebagliati.width-800.jpg"/>
            <figcaption><p data-block-key="o0nca">Snowboarder Ross Rebagliati at the 1998 Winter Olympics in Nagano, Japan, where he won gold for Canada in the men&#x27;s giant slalom. Image Credit: Mark Sandten, Bongarts, Getty Images</p><div class="credit"></div></figcaption>
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            <p data-block-key="31mmf">According to Pielke, <a href="https://www.govinfo.gov/content/pkg/CHRG-106shrg75594/pdf/CHRG-106shrg75594.pdf">Rebagliati’s case</a> gave the U.S. government the leverage it needed to lobby U.S. anti-doping leaders to include marijuana on the <a href="https://www.wada-ama.org/en/what-we-do/the-prohibited-list">World Anti-Doping Agency’s (WADA) Prohibited List</a>.</p><p data-block-key="bpegi"><a href="https://bit.ly/3BZs1hY">WADA was established in 1999</a> through a collective initiative led by the IOC, and maintains the <a href="https://www.usada.org/about/world-anti-doping-code/">World Anti-Doping Code</a> and prohibited list. Its key role is to standardize anti-doping regulations globally for Olympic sports. Director McCaffrey led the U.S. delegation at the first official meeting of WADA, after which “WADA looked far more like the institution the United States and its other international partners called for, than the original IOC-formed WADA” according to <a href="https://www.ojp.gov/pdffiles1/Digitization/185694NCJRS.pdf">a report</a> from the White House Office of National Drug Control Policy (ONDCP) on the agency’s actions and accomplishments from 1993-2000. The United States is also the largest <a href="https://www.reuters.com/article/us-sport-doping/u-s-threatens-to-pull-wada-funding-as-war-of-words-escalates-idUSKBN23V2TO">individual contributor</a> to WADA, which receives half of its funding from the IOC, and half from governments around the world. In 2020, the U.S. pledged over $2.7 million of the $37.4 million WADA budget. </p><p data-block-key="1q70f">Despite the U.S. government’s stance on social drugs, the ONDCP acknowledged that the athletic community itself was less concerned about cannabis than about performance-enhancing substances, like anabolic steroids, which can promote <a href="https://www.scientificamerican.com/article/a-rod-steroids-better-athlete/">tissue growth and muscle generation</a> and shorten recovery time after a workout.  </p><p data-block-key="7v64q">“In the course of our efforts to put in place an IOC ban on marijuana, athletes and sports officials at all levels—ranging from Olympians to high school coaches to youth athletes—informed ONDCP that they felt that the more urgent drug threat within the sports world was the use of performance enhancing drugs,” the <a href="https://www.ojp.gov/pdffiles1/Digitization/185694NCJRS.pdf">ONDCP report</a> stated. These concerns, the report notes, were “scientifically grounded” by the results of the 1999 <a href="https://www.drugabuse.gov/drug-topics/trends-statistics/monitoring-future">Monitoring the Future</a> survey, which concluded that youth steroid use increased roughly 50% over the prior year’s study. </p>
  

  
      <h3 data-block-key="zesoq"><b>Why is cannabis banned? </b></h3><p data-block-key="4r07d">According to WADA, any substance may be included on its prohibited list if it meets <a href="https://www.wada-ama.org/en/questions-answers/prohibited-list-qa#item-391">two of three criteria</a>: it has the potential to be performance enhancing, it poses a potential or actual health risk to the athlete, or it violates the “spirit of the sport.”</p><p data-block-key="epju3">WADA did not respond to questions from NOVA about the prohibited list or cannabis’s status on the list. But several recent studies investigate whether cannabis has performance-enhancing qualities in athletic competition. A <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7819470/">2020 literature review</a> by researchers not associated with WADA concluded, “there appears to be no reason based on current data to believe that cannabis has any significant ergogenic [performance-enhancing] effect.” An independent <a href="https://pubmed.ncbi.nlm.nih.gov/32734752/">2021 review</a> echoed that conclusion, saying cannabis “does not act as a sport performance enhancing agent as raised by popular beliefs.”</p><p data-block-key="d3j79">“In no circumstances is (cannabis) ever a performance enhancing substance. It is a net negative in terms of athletic ability and performance,” says Jeff Anderson, a professor of radiology and imaging sciences at the University of Utah who studies how the brain responds to compounds found in cannabis. “On the whole, people under the influence of THC are not able to perform as well on cognitive tests, they have slowed reaction times, decreased executive function, decreased attention.”</p><p data-block-key="ctuht"></p>
  

  
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      <p data-block-key="qiw02">Two decades after WADA banned cannabis, U.S. track and field sprinter Sha’Carri Richardson delivered a show-stopping performance <a href="https://www.youtube.com/watch?v=W5jWmeCZzp4">at the Olympic trials</a>, followed by an emotional interview in which she said she learned the week before that her birth mother had died. However, Richardson’s dreams of competing at the (delayed) 2020 Summer Olympics in Tokyo were dashed when she tested positive for THC, renewing a discussion about <a href="https://www.nytimes.com/2021/07/09/sports/olympics/marijuana-sports-performance-enhancing.html">cannabis’s impact on performance</a>.</p><p data-block-key="v42g">Since cannabis was banned, the public perception and legal landscape surrounding its use have changed greatly. While cannabis is illegal at a federal level, medical cannabis is legal in <a href="https://www.businessinsider.com/legal-marijuana-states-2018-1">37 states</a>, and cannabidiol (CBD)—reportedly used by <a href="https://www.upi.com/Top_News/US/2019/08/08/Poll-1-in-7-Americans-use-CBD-products-mostly-young-adults/9481565274864/">1 in 7 Americans</a>—is no longer prohibited by WADA. In the court of public opinion, where Rebagliati once found infamy, <a href="https://www.nbcnews.com/news/us-news/advocates-say-thc-does-not-enhance-sports-performance-so-why-n1272979">Richardson found support</a>, and her case left many <a href="https://www.scientificamerican.com/article/weed-shouldnt-be-banned-for-elite-athletes-some-experts-say/">questioning the science</a> behind cannabis’s prohibited status.  </p><p data-block-key="81m8n">“Drug testing is yet another tool of the drug war, and it’s a failure,” Kassandra Frederique, executive director of the Drug Policy Alliance, said <a href="https://drugpolicy.org/press-release/2021/07/drug-policy-alliance-statement-shacarri-unjust-suspension-us-olympics-team">in a statement</a>. “Sha’Carri’s suspension serves as a cautionary tale and a reminder of how insidious the drug war is in our everyday lives, far beyond the carceral state.” </p>
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            <img alt="Cannabis plants at Glass House Farms" class="richtext-image full-width" height="529" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/Cannabis-STILL2.width-800.png"/>
            <figcaption><p data-block-key="7x5qp">The cannabis plant contains over 400 chemicals, including the cannabinoids tetrahydrocannabinol (THC), the primary psychoactive compound, and cannabidiol (CBD). Image Credit: NOVA/GBH</p><div class="credit"></div></figcaption>
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      <h3 data-block-key="a0a4h"><b>Cannabis in the body</b></h3><p data-block-key="8i00l">Under the <a href="https://www.wada-ama.org/en/questions-answers/prohibited-list-qa#item-391">guidelines outlined by WADA</a>, “all natural and synthetic cannabinoids that mimic the effects of THC are prohibited, however CBD is not prohibited.”</p><p data-block-key="fpb3d">A cannabinoid is a compound that—no matter the source—interacts with cannabinoid receptors, which are found in <a href="https://www.pbs.org/wgbh/nova/video/endocannabinoid-system/">nearly every organ in the human body</a>. THC, for example, affects cannabis users by binding to cannabinoid receptors in and outside the brain, causing cells to behave differently. (The receptors also bind with the body’s natural cannabis-like chemicals, called <a href="https://www.pbs.org/wgbh/nova/video/endocannabinoid-system/">endocannabinoids</a>.) </p><p data-block-key="fmev2">Since the 1998 Winter Olympics, the THC metabolite limit for Olympic athletes has been raised from <a href="https://www.wada-ama.org/sites/default/files/resources/files/2020-01-11_guidance_note_on_substances_of_abuse_en_0.pdf">15 nanograms per milliliter to 180</a>, purportedly to only detect in-competition use of cannabis. However, the length of time cannabis will stay in a person’s system depends on frequency of use and the amount consumed.</p><p data-block-key="di4nr">This has to do with the way cannabis is metabolized. When smoked, ingested, or otherwise consumed, cannabinoids are absorbed and retained in many parts of the body, <a href="https://www.mayoclinicproceedings.org/article/S0025-6196(16)30825-4/fulltext">particularly fatty tissue</a>. Eventually, the THC byproducts are released and excreted through urine. However, daily consumers of cannabis accumulate THC faster than it can be removed from the body, reports Lia Tabackman for <a href="https://www.insider.com/how-long-does-weed-stay-in-your-system">Insider Health</a>.</p><p data-block-key="7ecv7">“Urine testing is one of the most common <a href="https://www.insider.com/how-long-does-weed-stay-in-your-system">drug testing methods</a>,” notes Tabackman. It is also widely used in elite sports. </p><p data-block-key="82lm1">According to a <a href="https://www.mayoclinicproceedings.org/article/S0025-6196(11)61120-8/fulltext">2008 report</a> on drug screening in the journal Mayo Clinic Proceedings, cannabis can be detected in urine for up to three days after a single use. For moderate users (4 times per week), cannabis can still be detected 5 to 7 days after last use. And in heavy daily smokers, it can be detected in urine for up to 30 days or more after they stop.</p><p data-block-key="2m3m0">But when it comes to quantifying behavioral impairment while using cannabis, a <a href="https://www.ojp.gov/pdffiles1/nij/grants/255884.pdf">National Institute of Justice study</a> led by researchers from RTI International found that measuring THC levels in blood, urine, and oral fluid were not reliable indicators of marijuana intoxication, regardless of how the cannabis was consumed.</p><p data-block-key="2hk4f">“Drug testing does nothing to show current impairment,” Frederique said <a href="https://drugpolicy.org/press-release/2021/07/drug-policy-alliance-statement-shacarri-unjust-suspension-us-olympics-team">in a statement</a>.  The [United States Anti-Doping Agency] must undo this archaic, inhumane, and unscientific policy.”</p>
  

  
      <h3 data-block-key="a0a4h"><b>&quot;An actual or potential health risk&quot; </b></h3><p data-block-key="amotf">In addition to prohibiting it, WADA considers THC <a href="https://www.wada-ama.org/sites/default/files/resources/files/2020-01-11_guidance_note_on_substances_of_abuse_en_0.pdf">a substance of abuse</a>, meaning it is “frequently abused in society outside the context of sport.” Cocaine, heroin, and MDMA (ecstasy) are also on this list. </p><p data-block-key="454eb">Some mental health experts have expressed concern over the development of <a href="https://pubmed.ncbi.nlm.nih.gov/26502112/">cannabis use disorders</a>, which may lead to increased anxiety or depressive disorders.</p><p data-block-key="5nkhl">“I&#x27;m among the group that wishes to see cannabis remain on the prohibited list,” says David McDuff, an addiction, trauma, and sports psychiatrist who has served on the IOC&#x27;s Consensus Panel on Mental Health in Elite Athletes.</p><p data-block-key="6jrev">When McDuff was working at University of Maryland College Park, he says he was shocked by the level of mental health symptoms and disorders within the college athlete population, and that the number of athletes using cannabis on a regular basis jumped across a number of sports.</p><p data-block-key="9ou5m">“I was referred to the substance misuse cases and many of them had comorbid anxiety or depressive disorders along with their cannabis use disorder,” says McDuff. “As a clinician, I can&#x27;t help but tie its use to reduced performance academically and athletically.”</p><p data-block-key="8sbc4">Other experts say that while the risk of cannabis abuse is real, it is unfair to not apply the same standards to alcohol, which was no longer prohibited <a href="https://www.wada-ama.org/en/questions-answers/prohibited-list-qa#:~:text=Effective%201%20January%202018%2C%20and,excluded%20from%20the%20Prohibited%20List.">as of 2018</a>.</p><p data-block-key="ff1ap">“Alcohol is something that’s far riskier than cannabis use for health, in terms of morbidity and mortality,” Angela Bryan, a professor of psychology and neuroscience at the University of Colorado Boulder, told <a href="https://www.scientificamerican.com/article/weed-shouldnt-be-banned-for-elite-athletes-some-experts-say/">Scientific American</a>. “I think [cannabis] should be treated like other drugs that people use for various reasons—alcohol, caffeine, nicotine. It should be regulated, but I don’t think it should be banned.”</p><p data-block-key="c8sii">McDuff points out that if cannabis is considered a substance of abuse, alcohol should be as well. “Alcohol use would surely violate all three of WADA&#x27;s criteria.”</p><p data-block-key="3kmgj">In September, WADA announced that it is <a href="https://www.wada-ama.org/en/media/news/2021-09/wada-executive-committee-endorses-recommendations-of-non-compliance-of-eight-anti">reviewing cannabis’s status</a> as a prohibited substance, but that it will remain prohibited in competition through 2022. The announcement followed a summer of <a href="https://sports.yahoo.com/wada-reviewing-cannabis-status-as-banned-substance-in-wake-of-sha-carri-richardson-ban-022541468.html">negative media attention</a> and criticism following Richardson’s suspension.</p><p data-block-key="e4r5c">In response to <a href="https://twitter.com/RepAOC/status/1411121868795518977?s=20">a request from lawmakers</a> to revisit its policies on cannabis, WADA <a href="https://www.wada-ama.org/sites/default/files/2021_07_letter_from_wada_president_to_jraskin_aocasio-cortez.pdf">pointed out</a> that historically, the U.S. has been “one of the most vocal and strong advocates for including cannabinoids on the Prohibited List.”</p><p data-block-key="14h51">“WADA has, for more than two decades, faithfully and obediently followed U.S. demands to assist in supporting its domestic drug policy agenda,” says Pielke, “only now to find itself subject to criticism from U.S. policymakers.” </p>
  

  
      

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Sha'Carri Richardson looks on after winning the women's 100 meter final at the U.S. Olympic Track & Field Team Trials on June 19, 2021 in Eugene, Oregon. Image Credit: Patrick Smith, Getty Images

<p data-block-key="8d456">Here’s how cannabis use became prohibited—and the science of its biological, psychological, and social effects.</p>

Cannabis doesn’t enhance performance. So why is it banned in elite sports?





  
      <p data-block-key="16pdf">Within the spiral-shaped M51 galaxy nicknamed “Whirlpool,” 28 million light-years from Earth, a Saturn-sized planet may orbit both a star that resembles our sun and a collapsed one.</p><p data-block-key="7nf5n">If confirmed, the planet would be the first astronomers have spotted outside the Milky Way—millions of light-years farther away than exoplanets astronomers have previously identified—NASA stated in a<a href="https://exoplanets.nasa.gov/news/1691/first-evidence-of-a-planet-identified-beyond-our-galaxy/"> press release on Monday</a>. The international team of astrophysicists and astronomers responsible for the find, led by Harvard &amp; Smithsonian astrophysicist Rosanne Di Stefano, believe the world is about as far away from its two stars as Uranus is from the sun. They published their findings this week in <a href="https://chandra.harvard.edu/photo/2021/m51/m51_paper.pdf">Nature Astronomy</a>.</p>
  

  
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      <p data-block-key="16pdf">An exoplanet is a planet that orbits a star other than our sun. And in the last three decades, scientists have accomplished what once seemed impossible: detect <a href="https://exoplanets.nasa.gov/">thousands of exoplanets</a>, despite their faintness in the night sky.</p><p data-block-key="3o30c">“Until now, all other exoplanets have been found in the Milky Way, and most of them have been found less than 3,000 light-years from Earth,” Amy Woodyatt <a href="https://www.cnn.com/2021/10/26/world/exoplanet-intl-scli-scn/index.html">writes for CNN</a>. To spot an exoplanet outside of the Milky Way, the team of researchers set its sights on a system where a sun-like star is in orbit around a neutron star or black hole—a system called an “X-ray binary.” It used NASA’s Chandra X-ray Observatory to detect the dimming of X-rays from the binary, NASA said in its press release. This dimming, during which the X-ray emission decreased to zero, lasted for about three hours, Linda Geddes <a href="https://www.theguardian.com/science/2021/oct/26/astronomers-spot-first-possible-exoplanet-outside-our-galaxy?utm_source=dlvr.it&amp;utm_medium=facebook">reports for The Guardian</a>, helping the team conclude the exoplanet is about the size of Saturn.</p><p data-block-key="dh6q0">This technique, in which scientists record the brightness of distant stars and then look to see if they dim slightly—a sign that a planet may be passing by or “transiting” the star—is called the transit method. From the dip in brightness, astronomers can infer how far a planet may be from its star, the planet’s size, and, by analyzing the starlight that shines through the planet’s atmosphere, Jamie Carter <a href="https://www.forbes.com/sites/jamiecartereurope/2021/10/25/the-first-planet-outside-of-our-milky-way-galaxy-has-been-discovered-during-an-x-ray-eclipse-say-scientists/?sh=3e201b9e67c4">writes for Forbes</a>, gather data about its composition. The transit method “is how most exoplanets are found in our own Milky Way galaxy,” Carter writes.</p>
  

  
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      <p data-block-key="16pdf">And it may also be key to hunting down exoplanets outside our galactic neighborhood, scientists believe. &quot;We are trying to open up a whole new arena for finding other worlds by searching for planet candidates at X-ray wavelengths, a strategy that makes it possible to discover them in other galaxies,&quot; Di Stefano <a href="https://www.nasa.gov/mission_pages/chandra/images/chandra-sees-evidence-for-possible-planet-in-another-galaxy.html">said in a NASA statement</a>.</p><p data-block-key="8b7re">But without more data, Di Stefano and her team can’t yet be certain that the object they spotted in the M51 galaxy is indeed an exoplanet. The dimming researchers observed using Chandra could be from a cloud of gas or dust passing by the X-ray source, though that’s unlikely according to their observations, NASA stated in its press release.</p><p data-block-key="a6ujm">The object’s large orbit within its star system will make it challenging to do another assessment. It will take another 70 years for it to cross in front of the X-ray binary again, “and because of the uncertainties about how long it takes to orbit, we wouldn’t know exactly when to look,” study co-author Nia Imara of the University of California at Santa Cruz told NASA.</p>
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            <img alt="NASA Exoplanet Illustration" class="richtext-image full-width" height="450" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/Exoplanet_Illustration.width-800.jpg"/>
            <figcaption><p data-block-key="epumw">Illustration of the exoplanet candidate transiting a star outside of the Milky Way. Image Credit: Chandra image gallery, NASA</p><div class="credit"></div></figcaption>
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            <p data-block-key="j723">If the object is a planet, it likely experienced a turbulent past, NASA stated in its press release. In fact, any exoplanet in its binary star system “would have had to survive the cataclysmic supernova explosion that created the neutron star or black hole from a previously existing star,” Geddes writes for the Guardian. The future of the system may be violent, too: The companion star could also explode, blasting any orbiting planets with high levels of radiation, NASA stated.</p><p data-block-key="ahkbh">Di Stefano, Imara, and the rest of their team are also setting their sights on exoplanet candidates in other galaxies, including some that are closer to Earth than M51. Already, they’ve used Chandra and the European Space Agency’s XMM-Newton to peer within 55 systems in M51, 64 in the “Pinwheel” galaxy Messier 101, and 119 in the “Sombrero” galaxy Messier 104, “resulting in the single exoplanet candidate,” NASA stated in its press release.</p><p data-block-key="2eagt">Study co-author Julia Berndtsson of Princeton University knows the team is “making an exciting and bold claim” by announcing they may have found an extragalactic exoplanet, and that other astronomers will assess their findings very carefully. “We think we have a strong argument and this process is how science works,” she told NASA.</p>
  

  
      

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A composite image of M51 with X-rays from Chandra and optical light from NASA's Hubble Space Telescope contains a box that marks the location of the possible planet candidate. Image Credit: X-ray: NASA/CXC/SAO/R. DiStefano, et al.; Optical: NASA/ESA/STScI/Grendler

<p data-block-key="18ujh">The exoplanet candidate is about the size of Saturn and located in a Whirlpool galaxy system 28 million light-years from Earth.</p>

In a first, astronomers find a potential planet outside the Milky Way





  
      <p data-block-key="csya1">Mozambique’s devastating civil war, fought between 1977 and 1992, seems to have had unexpected consequences: the rapid evolution of tuskless elephants.   </p><p data-block-key="9e6ii">Both sides of that war financed themselves largely through ivory trade, fueled by the rapid slaughter of <a href="https://www.pbs.org/wgbh/nova/article/predators-fear-elephants-bees-gorongosa/">Mozambican elephants</a>. In just 15 years, elephant populations in <a href="https://www.pbs.org/wgbh/nova/video/natures-fear-factor/">Gorongosa National Park</a> declined by 90%. By the early 2000s, there were only 200 elephants in the whole country, <a href="https://www.nature.com/articles/d41586-021-02867-y">Nature reports</a>. Among them were some individuals that, thanks to a rare genetic mutation, lacked tusks. With no ivory to offer, they were more likely to be spared and survive to pass on their tusklessness to their offspring.</p>
  

  
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      <p data-block-key="csya1">Since the end of the war, observers at the park have noted increased numbers of elephants with no tusks. A study <a href="https://www.science.org/doi/10.1126/science.abe7389">published today in the journal Science</a> dives deep into the elephant genome to show yet another unexpected way human affairs can sculpt our biological world. “It’s more than just numbers,” Rob Pringle, an ecologist at Princeton University and coauthor of the study, told <a href="https://www.theguardian.com/environment/2021/oct/21/ivory-poaching-evolution-tuskless-elephants-study">The Guardian</a>. “The impacts that people have, we’re literally changing the anatomy of animals.” </p><p data-block-key="enejd">The study authors started by analyzing historical video footage from prior to the civil war and contemporary elephant sighting data kept by local NGOs. That data showed that the dramatic decline in elephant populations in Gorongosa meant an equally dramatic increase in the proportion of surviving tuskless female elephants. Whereas at the start of the war, tuskless females made up 18% of the female population in the park, they now represent more than half, and about a third of female elephants born after the war were tuskless. In total, the authors estimate that across the 28-year period the study analyzed, tuskless females were some five times likelier to survive than tusked individuals. </p><p data-block-key="2dcqc">The researchers then drilled down into the selection mechanism by observing that there was no record of tuskless male elephants in the park. They hypothesized that any evolutionary mechanism acting on Gorongosa tusks would likely be an “X chromosome–linked dominant, male-lethal trait.” That means the mutation would be passed exclusively through female elephants, with just one copy needed to cause tusklessness in females and with male tuskless elephants dying in utero. If that were to be the case, tuskless mothers in the park would be much more likely to give birth to daughters. The data bore out that hypothesis. In the first decade after the war, they found that rates of tusklessness among female offspring of elephant war survivors continued at a rate almost twice that of pre-war populations. And not only that, but they found that tuskless mothers were giving birth to almost 66% daughters.</p><p data-block-key="9k67f">Finally, the authors moved to more nitty-gritty genomics to try to pinpoint the exact genes responsible for this wave of tusklessness. Comparing whole-genome scans for 18 Gorongosa elephants with and without tusks, they zeroed in on mutations on two possible genes: AMELX and MEP1a, both of which play an important role in tooth development in many mammals. AMELX is even associated with a similar “X-linked dominant, male-lethal” syndrome in humans—one that limits growth of our lateral incisors, our equivalent of tusks. </p>
  

  
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      <p data-block-key="mbagh">There’s plenty of precedent for the kind of rapid evolution the study authors are arguing for at Gorongosa. <a href="https://www.nature.com/articles/d41586-021-02867-y">Bighorn sheep</a> in Alberta, Canada; crickets in Hawaii; and <a href="https://www.theatlantic.com/science/archive/2018/07/hurricanes-irma-maria-lizard-grip/566006/">lizards in the Caribbean</a> have all been shown to exhibit remarkably fast transformation in response to evolutionary pressures. Still, to see a trait like tusklessness evolving within less than two decades, in a “long-lived, slow-reproducing species like the elephant, is incredible,” John Poulsen, a tropical ecologist at Duke University who was not involved in the study, told The Atlantic.</p><p data-block-key="2aq5o">And Gorongosa is not the first place where elephants at high risk of poaching have evolved away from tusks. <a href="https://www.newscientist.com/article/2294549-female-african-elephants-evolved-to-lose-tusks-due-to-ivory-poaching/">New Scientist reports</a> that fewer than 5% of male Asian elephants in Sri Lanka still have tusks. The Atlantic notes that <a href="https://www.pnas.org/content/106/Supplement_1/9987">Zambia’s South Luangwa National Park</a> and South Africa’s <a href="https://zslpublications.onlinelibrary.wiley.com/doi/abs/10.1017/S0952836902000845">Addo National Park</a> have both seen a dramatic rise in the proportion of tuskless female elephants.</p><p data-block-key="c74nd">But pinning down the exact genetic mechanisms at play and differentiating them from other pressures like climate change is always difficult in studies like this one, Chris Darimont, a conservation scientist at the University of Victoria, Canada, who was not involved in the study, told Nature. “It’s hard to prospect for these genes.” Plus, he added, there’s longstanding controversy about whether harvest pressure like hunting matters in the first place. Still, he called the genomic data offered in the new study “compelling,” saying the conclusions should serve as “a wake-up call in terms of coming to grips with humans as a dominant evolutionary force on the planet.” </p><p data-block-key="3d87d">A loss of tusks is not just a loss for elephants. Elephant tusks are “basically a Swiss Army knife for African elephants,” Pringle told New Scientist, helping them strip trees of bark, dig holes, find water. And many other animals indirectly depend on those tusks, snacking on bugs from barkless trees or getting water from those holes. “This is what maintains biodiversity,” co-author Shane Campbell-Staton, an evolutionary biologist at Princeton University, told New Scientist. “There are all these cascading consequences that can result from our actions that are quite surprising.”</p><p data-block-key="4m6me">With proper ecological protections in place, tusklessness will gradually disappear in Gorongosa, Pringle told The Guardian. “We actually expect that this syndrome will decrease in frequency in our study population, provided that the conservation picture continues to <a href="https://www.pbs.org/wgbh/nova/video/lions-mozambiques-gorongosa-national-park/">stay as positive</a> as it has been recently,” he said. “There’s such a blizzard of depressing news about biodiversity and humans in the environment and I think it’s important to emphasise that there are some bright spots in that picture.”</p>
  

  
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African elephant infant and adult. Image Credit: Michelle Gadd/USFWS, Flickr

<p data-block-key="js9a8">As the country’s civil war decimated elephant populations, the proportion of tuskless females rose dramatically. A new study explains why the tuskless trend continued in peacetime.</p>

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