Kissing bugs, seen here its with eggs, carry the parasite that causes Chagas disease. Image Credit: Jim Gathany/CDC

Chagas Disease More Prevalent in U.S. Than Thought

Edward Wozniak was sitting on his porch in Uvalde, Texas, one day in 2010 when a dog lying nearby stood up and a nickel-sized insect fell from its belly. Wozniak recognized the insect as a triatomine bug—the vector that carries the parasite Trypanosoma cruzi— and rushed to capture it. When the insect tested positive for the parasite, Wozniak launched a public effort to collect the bugs in Texas. “I had no problem getting almost 400 of them from in and around houses over a three-year period,” Wozniak said, “which blew me away.”The T. cruzi parasite causes Chagas disease, which is designated a “Neglected Tropical Disease” by the World Health Organization. Chagas is most prevalent in Central and South America, where experts estimate it afflicts some 6 to 8 million people, and has only recently gotten attention in the United States. Now, <a href="http://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0005074#pntd.0005074.ref005">a new study</a> has found the parasite that causes Chagas in overlapping populations of humans, dogs, coyotes, and insects in southern Texas, adding a new dimension to the evidence that the potentially fatal disease can be acquired locally in the U.S.
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T. cruzi lives in the feces of triatomine bugs. Nicknamed “kissing bugs,” these nocturnal insects bite people (often near the mouth) while they’re sleeping and feed on their blood. The bugs defecate while feeding, and if the feces are rubbed into the person’s bite wound, mouth, or eyes, they can contract the disease.Because Chagas victims are often symptom-free or experience only generic flu-like symptoms in the first weeks or months of infection, the disease often goes unnoticed. But some 30% of infected people will develop severe cardiac disease up to 30 years later. In Latin America, Chagas is a leading cause of cardiac complications, causing about 12,000 deaths per year. Because kissing bugs thrive in mud walls and poorly constructed shelters, poor communities are often hit the hardest.The researchers deemed the south Texas border area to be at high risk for Chagas partly because of its high poverty rate. The study focused on nine south Texas counties near the Mexican border to get a sense of the parasite’s prevalence across species. They tested samples of human blood as well as blood serum from shelter dogs and coyotes that had been collected during overlapping periods from 2005 to 2009. Additionally, they tested over 100 kissing bugs that had been collected near people’s homes in six of the nine counties from 2012 to 2013. They found T. cruzi in 56% of the kissing bugs, 8% of the coyotes and 3.8% of the dogs. Of the three people who tested positive for Chagas, they believe there is evidence that one of them contracted it locally.Based on these numbers, the researchers estimate that the Chagas disease burden in the Rio Grande Valley could be as much as 23 times higher than they had previously thought, which would mean 4,600 people in the region are currently infected.In Hidalgo County, both coyotes and kissing bugs tested positive for T. cruzi . Steven Hinojosa, lead epidemiologist at the Hidalgo County Health Department, said those study results were something he would “definitely expect to see.” He said he believes the disease is underdiagnosed, but it’s hard to know by how much since they only have three full years of data. Chagas disease only recently became a “notifiable condition,” meaning that doctors are required to report positive cases to government health officials.When a case is reported, treatment must be coordinated between the physician and the Centers for Disease Control and Prevention (CDC). This is because the two drugs used to treat the disease are not FDA regulated, said Melissa Garcia, an instructor at Baylor College of Medicine and an author of the study. Although the drugs are decades old, safe, and widely available in Latin America, they aren’t licensed in the United States because there is no perceived demand for them, she said.Before patients can get medication, they have to get tested for the disease. Everyone contacted for this article said that a primary obstacle to addressing Chagas in the United States is the fact that physicians are either unfamiliar with the disease or refuse to believe that it is present in this country. Although records of T. cruzi -infected kissing bugs in Texas date back to the 1930s and the first confirmed case of locally acquired Chagas was in 1955, many physicians consider the disease to be limited to immigrants who contracted it in Latin America.Wozniak, a zoonosis control veterinarian with the Texas Department of State Health Services, has seen physician pushback time and again. People still send him kissing bugs they find in their homes, which frequently test positive for both T. cruzi and human blood. When positive results are returned, he advises people to get tested themselves. “That’s where we hit a brick wall,” Wozniak said. They will sometimes go from doctor to doctor, only to be turned away, he added.
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Candace Stark of LaGrange, Texas, ran up against similar challenges. Stark, 52, donated blood in 2013 and was later notified that her blood had tested positive for T. cruzi . She went to her doctor, and he sent her to an infectious disease expert who said he had never treated a patient with Chagas. The CDC later confirmed her diagnosis, but when she asked her doctor if she should warn her neighbors about the disease, he advised her to keep quiet unless she wanted to be treated like Typhoid Mary. Stark eventually did receive an antiparastic drug to treat Chagas, but once treatment was complete, no follow-up plan was established.“I don’t know if [the drug] worked,” she said.By including both dog and coyote populations in their study, Garcia and her colleagues shed light on different transmission cycles of T. cruzi . “We can learn a lot by looking at wildlife because what they’re carrying can predict risk of human disease,” said Sarah Hamer, an assistant professor at the College of Veterinary Medicine and Biomedical Sciences at Texas A&amp;M University, who was not involved with the study. The parasite is strongly associated with wild animals, but domestic dogs may bridge the gap between wild animals and humans by serving as a host to kissing bugs and a “reservoir” of the parasite near human habitations.Garcia said that in Texas, veterinarians are “absolutely” more on top of Chagas than physicians. “I get many more vets that tell me they’re aware of [Chagas],” she said. She suggests it could be because dogs present with Chagas sooner, developing heart failure within a matter of months rather than decades. They are also at risk of eating the kissing bugs, which could explain why there is a higher rate of Chagas among animals than among people, she said.Despite the obstacles, Garcia feels that health experts and researchers are making progress in tackling Chagas in Texas. In 2015, the CDC awarded a $544,000 grant to a researcher at the University of Texas Health Science Center for Chagas outreach and education efforts.“I think in Texas we’re doing a decent job of getting the policies up to date,” Garcia said. “It’s now a mandatory reportable condition so at least it’s somewhat on people’s radar. However, in other states, like Louisiana, there’s not really any policy.”Meanwhile, Wozniak continues his efforts to educate the public about Chagas disease. “It’s something that’s here, it’s something that needs to be recognized, and people should be tested for it,” he said.
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side profile of a an elderly woman wearing glasses and looking down

More than 90% of Parkinson's patients, and almost all moderate to severe Alzheimer's patients, have some level of smell loss. (For illustrative purposes only.) Image Credit: srgpicker/Flickr (CC BY-NC 2.0)

Smell Test Could Tip Doctors Off To Alzheimer’s And Parkinson’s

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One of the earliest and most common warning signs of diseases like Alzheimer’s and Parkinson’s is not necessarily memory loss or tremors, but loss of smell. In fact, studies in recent years have shown that olfactory dysfunction is associated with many neurodegenerative diseases.Researchers hoping to understand this symptom tend to look for how each disease causes loss of smell in its own way. But in a review published in <a href="http://thelancet.com/action/showFullTextImages?pii=S1474-4422%2817%2930123-0">Lancet Neurology</a>, Richard Doty, director of the Smell and Taste Center at the University of Pennsylvania, suggests that there may be a common mechanism causing olfactory dysfunction across illnesses.Doty thinks that finding common factors causing smell loss could point to processes that initiate a number of neurodegenerative diseases. In the course of his research he reviewed different diseases, looking for a common cause for the varying levels of olfactory loss. After ruling out a number of possibilities, including environmental and physiological factors, he found evidence for one common thread: damage to neurotransmitter and neuromodulator receptors in the brain that affect the brain’s ability to process smells.
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Not all smell loss is tied to a neurological disease; it can also be caused by the common cold as well as a history of smoking, regular aging, and other factors. While Doty’s approach may be promising, research into smell loss is difficult because of the lack of early data.  “Smell testing isn’t part of a standard check-up, and people don’t recognize a smell problem themselves until it’s already severe,” Doty said <a href="https://www.pennmedicine.org/news/news-releases/2017/may/penn-expert-probes-possible-reasons-for-loss-of-smell">in a statement</a>. Some doctors think that should, and could, change.Here’s David Noonan, reporting for <a href="https://www.scientificamerican.com/article/smell-test-may-sniff-out-oncoming-parkinsons-and-alzheimers1/">Scientific American</a>:The simplicity and low cost of a smell test—$26.95 retail, before additional doctor or hospital charges—make it especially appealing in neurology, a field dominated by positron emission tomography (PET) scans, dopamine transporter single-photon emission computed tomography (DAT-SPECT) imaging and other expensive technologies. Because it is so economical, [Davangere Devanand, a professor of psychiatry and neurology at Columbia University] says researchers should incorporate olfaction testing into studies that look at other Alzheimer’s risk factors in large populations.Research beginning in Japan will look at smell and physiological changes in older populations over the next few years, possibly clarifying any links between those variables.Establishing a universal cause for smell loss won’t necessarily hasten a cure for neurodegenerative diseases, but researchers are working on other approaches including using bacteriophages to block and even reverse plaque development in the brain, as <a href="http://www.pbs.org/wgbh/nova/next/body/phage-alzheimers-cure/">NOVA Next reported</a> in 2016.
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Zika May Have a Startlingly High Sexual Transmission Rate

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 When Zika swept across Latin America in 2015, a couple of alarming developments quickly followed: microcephaly in fetuses and a murky association with Guillain-Barré Syndrome. Despite ongoing research, much about the virus remains a mystery, including many details of how it spreads.


 Mosquitoes are the most obvious vector, but as far back as 2011, virologists suspected that Zika might also be transmitted sexually, a hunch that was confirmed last year. Still, researchers had no idea how easily the virus could be passed through sexual contact.


 Now,
 <a href="https://wwwnc.cdc.gov/eid/article/23/8/17-0036_article">
 a pilot study
 </a>
 offers new insights about this hard-to-research transmission route, which could potentially spread the virus to new areas. In the study, 12 out of 16 monkeys exposed to Zika through sexual routes tested positive for the virus.


 It’s been nearly impossible to identify sexually transmitted cases in outbreak regions because they’re masked by mosquito-transmitted cases, which has made the potentially important vector practically invisible. On top of that, 80% of Zika infections are asymptomatic, meaning that people may not even know they have the disease and thus might be excluded from data about infection rates.


 “The study provides a starting point to where we can start gauging risk,” said lead author Andrew Haddow of the United States Army Medical Research Institute of Infectious Diseases. To see how transmission rates had been studied in the past, Haddow said his team looked to HIV/AIDS research. As with that research, this initial model will need to be refined to truly understand human risk, he said.


 “This is really big news,” said Enbal Shacham, an associate professor of behavioral science and health education at Saint Louis University, who was not involved in the study. Shacham said that because so little is known about how—and how efficiently—Zika is transmitted sexually, any new information is valuable.

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 The study involved 16 monkeys: eight rhesus and eight cynomolgus macaques. For each group, the researchers exposed four monkeys to Zika by delivering the virus to the vagina and the other four by delivering it to the rectum.


 Researchers anesthetized the animals and, using a lubricated feeding tube, administered a single dose of the virus that was comparable to the highest amount reported in human semen. The method was specifically intended to be nontraumatic, avoiding microtears in the tissue. “We wanted to see what happened in an ideal situation,” Haddow said.


 Four of the eight monkeys inoculated vaginally became infected (two of each species), while all eight of the individuals inoculated rectally were infected.


 “We were pretty surprised by that,” Haddow said, adding that he and his team expected maybe one in four monkeys to become infected.


 The new research provides “important proof” that primates can be infected through vaginal and rectal mucous membranes, said Akiko Iwasaki, a professor of immunobiology and molecular, cellular and developmental biology at Yale School of Medicine.


 Despite the infections, none of the animals showed symptoms of the disease. Based on the amount and duration of infectious virus in the macaques’ blood, Haddow’s team thinks humans infected through sexual transmission may be capable of infecting mosquitos with the virus.


 Haddow and his coauthors conclude that sexual transmission could be a way for the virus to maintain itself in the absence of mosquito transmission, and it might increase the likelihood of Zika spreading into new areas. “The possibility exists that you could have silent transmission, where somebody gets Zika sexually and has no idea,” Haddow said.


 Researchers know that animal models have their limitations, though. John Brooks, a medical epidemiologist with the Centers for Disease Control and Protection (CDC), said we should be “very circumspect” when translating data from research animals to what it means for humans. Nonetheless, he pointed out that both groups of monkeys in Haddow’s research showed detectable virus in their blood for about the same amount of time it stays in humans.“To me that’s saying, okay, it’s behaving in this animal model like it’s behaving in humans,” Brooks said.

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 Still, he’s not worried about Zika spreading through sexual transmission alone. “Despite everyone’s concern that Zika could be spreading quietly through the country through sexual transmission, we’re just not seeing it,” Brooks said. “And people would have begun to recognize that by now.”


 In the United States, the CDC knows of about 50 couples among whom sexual transmission of Zika has occurred. Researchers think those cases are the tip of an iceberg, Brooks said, adding, “I don’t know how big that iceberg is.”


 Based on rough estimates of the number of travelers arriving in the United States from active Zika regions, the CDC estimates that 200,000 affected men could enter the country per year. Brooks says that’s a lot of opportunity for the virus to transition and to be sustained, but that hasn’t been observed. (While Zika can be transmitted from women to men, that’s far less common than men transmitting it to their partners, and there is only one known case of woman-to-man transmission.)


 One reason that Zika outbreaks in the U.S. haven’t been traced to sexual transmission could be that, unlike some sexually transmitted diseases which remain infectious until treated (and even after), Zika clears from the system fairly quickly, Brooks said.


 “In Zika, your body mounts a really effective immune response,” he said. Within about a month after infection, 50% of men will no longer have Zika in their semen, he said. After 81 days, that number rises to 95%.


 While the dose of virus used in Haddow’s study is comparable to what can be found in human semen, Brooks said, “men don’t stay at that level for very long.” The level of Zika in semen declines “rapidly and steadily,” he added, although researchers don’t know at what point someone is no longer infectious. But, he points out, the known cases of sexual transmission in the United States have shown that people who infect their partners generally do so early in their illness—something researchers can determine by the timing of the second person’s illness.


 For men who have traveled to an area with active Zika transmission, the CDC recommends abstaining from sex or using a barrier protection method (like a condom) for six months after leaving the area. For women who have traveled, the recommendation is eight weeks.


 Haddow’s latest research builds on the legacy of his grandfather—who was one of the discoverers of Zika—as well as his own groundbreaking work. It was Haddow who pieced together clues that Zika might be sexually transmitted.


 Despite the new research, the unknowns surrounding Zika extend far beyond its sexual transmission rate. Iwasaki, who has studied Zika in mice, said it can cause shrinking of testes and reduced sperm count in those animals. “Zika virus may be a silent disease with significant reproductive impact in humans for years to come,” she said.


 Brooks said it took about 20 years to get the necessary data about HIV to run current models to assess both per-act risk of HIV transmission through various routes and the impact of prevention strategies on specific kinds of transmission.


 Additionally, Haddow says there’s a possibility of a so-called sylvatic cycle of Zika, in which monkeys transmit the virus to each other sexually. In this scenario, animal populations could serve as a reservoir of the virus, keeping it alive without human hosts.


 “It’s going to take years to investigate this stuff,” Haddow said.


 Image credit:
 <a href="https://commons.wikimedia.org/wiki/File:197-Zika_Virus-ZikaVirus.tif">
 David Goodsell (CC BY 4.0)
 </a>

In a pilot study, 12 out of 16 monkeys exposed to Zika through sexual routes became infected.

Recycling plastic only delays its eventual disposal.

76% of All Plastic Ever Made Has Already Been Discarded

It’s woven into clothing, spilling out of recycling bins, and floating in massive patches across the ocean. Plastic is everywhere—and now a global analysis of mass-produced plastic reveals that of the 8.3 billion metric tons of plastic created by 2015, 6.3 billion are already out of use. What’s more, most of it is in landfills and nature.Mass production of plastic began around 1950, and has since exceeded almost all other man-made materials. It hasn’t surpassed cement and steel, but the study’s authors point out that those materials are largely used in construction, providing decades of use. Plastics, on the other hand, mostly go toward short-term use.“Half of all plastics become waste after four or fewer years of use,” said Roland Geyer, associate professor of industrial ecology at the University of California, Santa Barbara, and lead author of the paper. The study, which was published in the journal Science Advances, looked at production, use, and lifetime data of polymer resins, synthetic fibers, and additives across eight industrial sectors.While plastics used in industrial machinery or construction regularly have lifespans exceeding 20 or 30 years, respectively, the largest market for plastic is packaging. And most plastic packaging is discarded in the same year it’s produced.Of the total plastic discarded by 2015, the researchers determined that 79% went into landfills or the natural environment, 12% was incinerated, and 9% was recycled. Recycling, they point out, only delays final disposal, and it’s unclear whether recycling actually prevents new plastic from being produced.“What we are trying to do is to create the foundation for sustainable materials management,” Geyer said. “Put simply, you can’t manage what you don’t measure, and so we think policy discussions will be more informed and fact based now that we have these numbers.”At the current rate, the researchers project that total plastic production will reach 34 billion metric tons by 2050, with total plastic waste reaching 12 billion metric tons. Mass-produced plastics do not biodegrade “in any meaningful way,” the authors note, pointing out that sunlight weakens plastic and causes it to break into tiny fragments known as microplastics. These fragments plague oceans and freshwater ecosystems alike—the same group of researchers estimated in a previous study that 8 million metric tons of plastic entered the ocean in 2010 alone.Increased research and media attention has led to some efforts to address the issue of plastics in water, and this month marks the beginning of a U.S. ban on <a href="http://www.pbs.org/wgbh/nova/next/earth/800-trillion-plastic-microbeads-go-down-drains-every-day/">plastic microbeads</a> commonly used in personal care products. But little is known about how plastics affect terrestrial ecosystems.
Image credit: <a href="http://www.misawa.af.mil/News/Photos/igphoto/2000070915/">U.S. Air Force photo by Tech. Sgt. Phillip Butterfield</a>
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We’ve Mistakenly Assumed That Coal Is Effectively Unlimited

Some energy and climate projections may have been distorted by inflated estimates of available coal, a new study shows.Since the 1990s, climate and energy models have assumed we’d use the entirety of the world’s coal reserves, but it has become clear in recent decades that only about a third of all coal deposits can feasibly be recovered.But, researchers warn, changing those assumptions doesn’t alter the forcasts of the lowest-emission—but still risky—climate scenario.The mismatch in coal usage estimates and actual availability results surprised researchers Justin Ritchie and Hadi Dowlatabadi, of the University of British Columbia, who published their findings last month. Coal had once been assumed to be essentially unlimited (for the purposes of modeling), and their new estimates severely constrained the potential supply—so much so that the worst case climate scenario put forth by the Intergovernmental Panel on Climate Change, which assumes an increase in future coal use, may not be possible. At least not in the way scientists thought.When Ritchie and Dowlatabadi adjusted their model to account for the lower coal estimates, they substituted natural gas or renewable energy for additional coal use in coal’s place. When natural gas picked up the slack, emissions fell by 15%, and when renewable energy filled the gap, emissions estimates fell by 30%.Eric Roston, reporting for Bloomberg:The discovery that there’s a whole lot less coal to burn would seem a gift to skeptics of climate change and opponents of climate policy. But Ritchie’s paper is a double-edged sword. The same finding that shrinks CO2 emissions may also lower the cost of dealing with global warming, making the Paris Agreement that addresses climate change easier to achieve.Although the study may lead to more well-informed models, it doesn’t necessarily indicate a brighter future for climate. Even low-end scenarios—in which emissions drop enough to limit warming to 3.6˚ F—would bring drastic changes to the climate system.
Photo credit: <a href="https://www.flickr.com/photos/37467370@N08/7639182256/">Greg Goebel/Flickr (CC BY-SA)</a>
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Human cells with acute myelocytic leukemia.

'Living Drug' Therapies Could Revolutionize Cancer Treatment

Last week, an FDA panel unanimously <a href="https://www.nytimes.com/2017/07/12/health/fda-novartis-leukemia-gene-medicine.html">recommended</a> that the agency approve a treatment that genetically alters a patient’s immune cells to fight leukemia from within. This kind of “living drug,” called gene therapy, would be the first of its kind on the market in the United States if the FDA approves it.The treatment has to be created from scratch for each individual patient, using their own T cells—white blood cells used by the immune system. T cells are removed from patient’s bloodstream, then genetically engineered to recognize and kill cancer. The weaponized cells are then multiplied and reintroduced into the patient.Novartis, the company seeking approval for the first therapy, presented data from an 18-month study in which 52 out of 63 patients with B-cell acute lymphoblastic leukemia went into remission.The products that are closest to approval focus on blood cancers like leukemia and lymphoma, which represent about 80,000 of the 1.7 million cancer diagnoses in the United States each year. Here’s Denise Grady, reporting for The New York Times: “This has been utterly transformative in blood cancers,” said Dr. Stephan Grupp, director of the cancer immunotherapy program at the Children’s Hospital of Philadelphia and a professor of pediatrics at the University of Pennsylvania. “If it can start to work in solid tumors, it will be utterly transformative for the whole field.”Solid tumors are highly resistant to the kinds of altered T cells that have have proven effective against blood cancers. Although researchers are working on approaches for solid tumors, the challenge they present means that gene therapies may be further off for breast, ovarian, prostate, lung and pancreatic cancers, for example.But T-cell approaches aren’t the only thing out there. Researchers at the University of Texas MD Anderson Cancer Center are harnessing the power of so-called natural killer cells, another kind of immune cell that can be genetically altered to attack cancer. Unlike T cells, natural killer cells can be taken from cord blood donated at childbirth, and the modified cells can be safely given to multiple patients. What’s more, they have a kind of drug-activated “off switch,” which can be flipped in the event that the treatment causes unmanageable side effects.After “promising” studies in mice, the researchers have opened a study for patients with relapsed or treatment-resistant leukemia and lymphoma. The first patient is to be treated with the natural killer cell method this week.
Photo credit: <a href="https://visualsonline.cancer.gov/details.cfm?imageid=2336">National Cancer Institute</a>
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A Jupiter-like planet and its hot "A-type" host star.

Newly Discovered Planet Is Hotter than Most Stars

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Astronomers have discovered a giant exoplanet that’s hotter than most known stars. Clocking in a 7,820˚ F, the planet known as KELT-9b orbits a star almost twice as hot as the Sun.The planet, which is almost three times the size of Jupiter, is “tidally locked,” meaning that the same side is always facing its host star. It’s also extremely close to its host, taking only one and a half Earth days to orbit the giant blue star.The team that made the discovery, led by astronomers at The Ohio State University and Vanderbilt University, <a href="http://www.nature.com/articles/nature22392.epdf?referrer_access_token=Y8d_4QkewKNy0J7XHlThSdRgN0jAjWel9jnR3ZoTv0MYcvHnMqfjUp746R6R_ZGjf5O7TtFcqKksjUiYfUP9m2y59Btw4rLkTEulxBKCyCICNDnfpXxyksvIXAK3mQIylPFAdr5N3qYS3BUgzH_mmkJ_OkU99x-MXtjlvVzDq_9vi9U4zBNflgHq-LngWjZ2pwdS7E5sOa_WTfXQHHOAaaNN3Z236b1Lora83iKNg4WCwR9-3oFCDtJ-mP7zFuaZTBUhiCydhv4OSsAkVFzSzMxtGSnNGm55aHg3s5e1_Vo5erBYOjYWmr3J2g5WuoaK&amp;tracking_referrer=www.npr.org">reported</a> its findings in the journal Nature. Scott Gaudi, an astronomer at Ohio State and lead author on the study points out that KELT-9b’s extreme temperature affects it in unusual ways.“It’s a planet by any of the typical definitions based on mass, but its atmosphere is almost certainly unlike any other planet we’ve ever seen just because of the temperature of its day side,” Gaudi said <a href="https://news.osu.edu/news/2017/06/05/hotplanet1/">in a statement</a> .Here’s Ben Guarino, reporting for the <a href="https://www.washingtonpost.com/news/speaking-of-science/wp/2017/06/05/the-hottest-planet-ever-discovered-has-an-atmosphere-as-warm-as-a-stars/?utm_term=.0088be4a90d7">Washington Post</a> :Though scientists had previously discovered “hot Jupiter” planets, so named for their extreme temperatures and gas giant nature, all fell about a thousand degrees Celsius short of KELT-9b. KELT-9b is at the “extreme end of the population” of known gassy, hot giants, said <a href="https://www.astro.ucsc.edu/faculty/profiles/singleton.php?&amp;singleton=true&amp;cruz_id=jfortney">Jonathan Fortney</a> , a University of California at Santa Cruz professor who creates computer models to determine what’s in an exoplanet atmosphere.
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Fortney, who was not directly involved with this paper, was asked to model KELT-9b’s atmosphere. He declined. “I can’t possibly do that. The planet’s way, way too hot,” he said.A planet’s atmosphere is typically made up of molecules, which are made up of atoms bound together. Molecular hydrogen gas is common on Jupiter, for instance, as are water vapor and other gases on Earth. KELT-9b’s dayside is an exception. The heat breaks molecules into its constituent atoms. “Almost all the elements are in atoms, not in molecules,” Fortney said. “It’s essentially too hot for molecules to exist.”The team made the discovery using relatively inexpensive off-the-shelf technology in the form of a KELT, or Kilodegree Extremely Little Telescope. Gaudi said their discovery is unusual because astronomers typically focus on smaller, cooler stars whose planets might support life. By contrast, KELT-9b’s host star is so hot that the exoplanet may be trailing a comet-like tail of its own evaporated material.
Image credit: Robert Hurt, NASA/JPL-Caltech
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Robin Kazmier

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