[Music] it's well known that after his defeat at the end of the Third Age the Dark Lord Sauron fled Mordor into the sky and traveled about 25 light-years towards the constellation Pisces extremists we still see his terrible flaming eye gazing down at us fighting his times The Incredible Hubble Space Telescope picture as the star thermal laws does excite the imagination doesn't it today I want to set your mind to B this isn't really the Eye of Sauron probably thermal law is an a-type star about twice as massive and much hotter and brighter than the Sun at only 25 light years away it's the 18th brightest star on the sky but even as a non Dark Lord it's a fascinating object let's look at some pictures that dot in the middle marks the location of the star but you can't actually see firmly in the scripture because the mask was placed directly in front of them for the picture such a mask is called a coronagraph and its purpose is to block the bright light of FOMA law so that it's faint surrounding structures can be studied the fluted pupil is the shadow of that coronagraph sadly it's not a real part of the structure but the surrounding ring is very real firm lured itself is brightest in the ultraviolet to our eyes it twinkles bluish white on the night sky but the ring is brightest in the infrared here is some infrared pics from the social space telescope and from Alma commercial image the star doesn't even need to be masked we're seeing the heat flow of a giant ring of ice and dust but 40 billion kilometres in diameter it's the remnant of foam alots proto planetary disc the whirlpool of debris left over after the star formed and from which a planetary system may now be forming that makes FOMA law an incredible laboratory for us to study our own solar system and how it may have formed here's how we think that goes start with a dense crawl in a giant molecular cloud called in a drift then mostly hydrogen gas yields to gravity once it reaches the critical genes mass as the gas classes is builds up since and densities until the pressure of the gas dramatically slows collapse and you have a protostar surrounded by a great cloud of dust and gas the protostar continues to collapse more slowly until eventually the core gets hot and dense enough to ignite in fusion the star is born and our flowing energy resists any further collapse conservation of angular momentum has a central star spinning rapidly the surrounding debris also rotates and that rotation allows it to resist falling towards the central axis but gravity can still pull the debris together in the up-down direction so it flattens into a disk eventually winds from the newborn star in the center disperses extra gas and dust revealing whatever planets manage to form from the debris in that time the formation of planets itself is a fascinating process the leading formation model is for accretion in which tiny granules are drawn together and clumped by static electricity they grow in size until they're large enough that they can start collecting more material through collisions these collisions must be very gentle or else pieces will shatter on impact eventually the growing Rock has enough mass to attract material through its own gravity at this point it's a planetesimals at about a kilometer in diameter by the time it's at least ten percent of the Earth's mass it will have cleared its orbit of other planetesimals and will have rounded out into a planet scarran solar system went through this process four and a half billion years ago and the solar wind has long since dispersed what we left have our own protoplanetary disc this is believed to have happened some tens of millions of years after the Sun first form so milord is a strange case it's going through an unusually long puberty the star is 440 million years old they're still very young but it's surprising that it's holding on to part of its protoplanetary disk for so long the Herschel and Alma images show very clearly that the ring has sharp edges particularly that inner edge the leading idea is that newly formed planets carved out that ring with their gravity check out sentence F ring it's clean lines are carved by what we call shepherd moons in foam Lords case it may be shepherd planets guiding the dust into a well-defined track just like strider guiding a pack of hobbits through the wild every grain of dust in the foam allured system is in orbit around the star the closer an object corbett's to a given star the faster it moves through space the father asked orbits the slower it moves and Kepler's third law tells us less so a planet passing along the inside of the dust ring overtake each grain of dust and tugs them gently forward infused with extra energy that dust orbit shifts outwards a planet passing along the outside of the dust ring pulls back on the dust and that slows it down having lost energy that dust spirals closer towards the star pushed outwards and inwards by the shepherd planets so dust ring boundaries sharpened between them but I share really planets there a wise man once said there is nothing like looking if you want to find something you certainly usually find something if you look but it's not always quite for something you are after in fact is very possible so we've actually found the planet that carves out the inner edge of that ring so milord be shows up as a dry orbital body in Hubble images it's bright enough to be a few times Jupiter's mass however it seems to be completely invisible in the infrared it may actually be a much smaller planet still reeved in the dust of its formation and the light that Hubble is seeing is just reflected starlight from thermal or or even cooler it may be a planet with a giant reflective ring system if so firm lot really does seem to have a thing for rings suspicious by the way FOMA Lord bee has a cooler name its Dagon selected by the International Astronomical Union from public submissions now we're mixing our mythologies a bit but I just feeling the stag on the evil Lovecraftian person diamond god thing we've got along just fine with salad well originally Dagon was an ancient committing deity but Cthulhu Mythos is so much more fun in fact the entire planet may be a myth instead it may be a collection of debris leftover from a recent collision but the smart money is on it being a real planet take on highly eccentric 1700s earth year orbit is larger than Neptune that's far out it shouldn't really have been enough resources to build a planet even at the lower end of Dagon status at around three earth matters one possibility is that a performed closure in at some critical point it may have interacted with another massive planet in the system sending that planet spiraling closest to thermal ought to become a so-called hot Jupiter while Dagon was flung way out in fact a similar model may explain the locations of our four gas giant planets Jupiter and it's cousins may have formed close together until a close encounter destabilized the whole solar system and fund the gas giant into their current more spread-out positions ferma law gets even more interesting it actually has two stellar companions making it a rare trinary star system one companion is a red dwarf that may actually have its own protoplanetary disc and that will make sense if they formed at the same time start typically forming groups as very large clouds of molecular hydrogen collapsing break apart into separate pieces the stars don't always stay in the same groups for example our Sun has long since left its birth siblings behind but we're more likely to catch loosely bound stellar systems early in their lives by the way the third star in the system is a flare star violently fluctuating due to magnetic storms on its surface in fact it's exact type is a B Y Draconis variable smog finally found his way to sour onside the fiery eye of Sauron wielding rings within rings with our solar system once so mortal like we're going to need more observations to figure out whether firmly is typical of stars in their youth or is actually truly unusual we'll need to figure out if this planet is real and what causes it's strange mismatched invisible and infrared lights only then can we start to use it to learn about our solar system's early years lots of questions still but one does not simply cease