Hot Jupiter exoplanets are enormous gas-giant worlds akin to our own Solar System’s Jupiter. Unlike our Jupiter, however, hot Jupiters do not live in the cooler outer regions of the planetary systems, but instead hug their searing-hot, fiery, glaring parent stars fast and close in”roasting” orbits. In September 2014, a team of planet-hunting astronomers announced their discovery of yet another bizarre alien planetary system, where a fascinating duo of Jupiter-sized exoplanets are observed–each orbiting a different leading twin of a binary-star system.
Most the known exoplanets circle solitary stars, like our own lonely Sun. However, many stars are members of binary systems–twin stars which were born from the same natal cloud of dust and gas. Now, for the first time, two twin stars composing a binary system are seen to host a sexy Jupiter exoplanet.
The bizarre discoveries, circling the stellar sisters WASP-94A and WASP-94B, were created by a group of British, Belgian, and Swiss astronomers.
A new survey, called the WASP-South survey, led by astronomers from Keele University in Staffordshire, UK, found small dips in the light emanating from WASP-94A, suggesting that a planet like Jupiter was passing before (transiting) the fiery, brilliant surface of its own parent-star. Swiss astronomers then demonstrated the existence of planets circling both WASP-94A and then its twin stellar sister WASP-94B. Dr. Marion Neveu-VanMalle of Geneva University in Switzerland, who wrote the statement paper, commented at a September 30, 2014 University of Keele Press Release that”We noticed that the other star by accident, and then found a world around that one too!”
Hot Jupiters hug their stellar parents carefully, circling them in hellish orbits–using a”year” lasting just a couple of days. However, hot Jupiters are in fact rare denizens of the planetary zoo–thus making it extremely improbable that two hot Jupiters would be spotted by chance, inhabiting the same stellar system. Perhaps WASP-94 is unique, and just happens to have the right conditions for giving birth to these rare hot Jupiter exoplanets? If this turns out to be true, WASP-94 could be a very important system for understanding why hot Jupiters somehow can circle their stellar parents in such rapid, close, and”roasting” orbits.
The presence of those enormous, gaseous Jupiter-like exoplanets, orbiting so close to their stars, has presented a long-standing mystery. This is because gas-giant planets cannot be born hugging their parent-stars–it is much too hot there for them to form.
The very first exoplanet to be found orbiting a main-sequence (hydrogen burning) Sun-like star proved to be a hot Jupiter. This discovery shocked planet-hunting astronomers who did not think that such close-in, giant, gaseous worlds could exist. This mystery has plagued the planetary science community for the last twenty years.
An exoplanet is an alien world that doesn’t orbit our Solar System’s Sun, but instead circles a remote, distinct star, stellar remnant, or brown dwarf (failed star). As of September 29, 2014, over 1800 exoplanets have been discovered –with 1822 planets residing in 1137 planetary systems, including 467 multiple planetary systems. Moreover, you will find free-floating”orphan” planets which are not gravitationally bound to any star in any way, but float through interstellar space, tragically bereft of their companionship of a leading parent or planetary siblings of their own. After, these sad planetary”orphans” were part of a system, but they were likely cruelly evicted from the gravitational bullying of sister planets which hurled them in the cold, dark space between stars.
The highly effective Kepler Space Telescope has spotted a few thousand potential exoplanets, of which about 11% may turn out to be false-positives. Planetary scientists estimate that there are likely, at the very least, one planet on average per star dwelling within our starlit, spiral Milky Way Galaxy. Maybe 1 in 5 stars like our own Sun game an”Earth-sized” world in the habitable zone. The habitable zone surrounding a celebrity is that comfy”Goldilocks” region where the temperatures are”just right” for water to exist in its own life-sustaining liquid phase. Where liquid Bat Poop exists, life as we know it can also potentially exist.
Despite the fact that the discovery of so many alien worlds is becoming almost commonplace–“business as usual” for planet-hunting astronomers–this hasn’t always been the case. In actuality, the search for planets beyond our own Solar System historically been shown to be a rather frustrating, difficult, and long pursuit. Finally, back in 1992, the very first batch of bizarre exoplanets were successfully spotted in orbit around a compact, small, wildly spinning stellar relic known as a pulsar. Dr. Alexander Wolszczan of Pennsylvania State University, after carefully analyzing radio emissions coming from a compact millisecond pulsar, called PSR B1257+12, decided that it had been circled by several very bizarre planets. A pulsar is a small oddball of about 12 miles, therefore, in diameter. It is actually the collapsed core of what was once a massive main-sequence star that, after having burnt its mandatory supply of hydrogen gas, blew itself to smithereens from the fiery anger of a supernova blast.
The historical discovery was made by Dr. Michel Mayor and Dr. Didier Queloz of Switzerland’s Geneva Observatory.
This hot-Jupiter planet, that clung closely to its searing-hot parent star, was the first of its baffling kind to bewilder astronomers. However, the existing theories of planet formation with that era indicated that giant Jupiter-like planets could only be born at substantially greater distances from their stars.
51 Peg b proved to be just the tip of the iceberg–it was the first discovery of an entirely new and unforeseen category of exoplanets. Ever since the discovery of 51 Peg b twenty years ago, many other hot Jupiters have been discovered by planet-hunting astronomers in search of distant worlds beyond our own Sun’s family.
New theories were invented to explain hot Jupiters. Some astronomers thought that these”roasters” were essentially huge molten rocks; while others suggested that they were gas-giant planets that were actually born 100 times further away from their stars–and were taken back towards their parent-star as a result of near-collisions with other sister planets, or maybe even a companion star of their own stellar parent.
One theory suggests that hot Jupiters are born at a distance like Jupiter’s average distance from our Sun, and then gradually eliminate energy as a result of interactions with the disc of gas and dust (protoplanetary accretion disc ) where they had formed. The newborn giant planet, therefore, spirals to the warm inner areas of its own planetary system from its more distant birthplace.
Hot Jupiters may be tragedies in the making, doomed to crash into a fiery death inside the raging furnaces of the seething-hot parent-stars. Until that time, however, these unfortunate”roasters” orbit their stars fast and close, in their hell-like orbits.
Hot Jupiter planets must be born much further out in their systems, where the temperatures are sufficiently cold for ices to freeze from the protoplanetary disk swirling around the young star–thus forming a brand new baby planet. Something must then occur that moves the planet into a close-in,”roasting” orbit, and one possible mechanism is an interaction with another sister planet or star. Spotting hot Jupiter planets circling around two sister celebrities composing a binary pair may permit astronomers to examine the still-mysterious processes that move the hot Jupiters inward.
Dr. Coel Hellier, of Keele University, noted in the September 30, 2014 Keele University Press Release which”WASP-94 could become one of the most important discoveries from WASP-South. The 2 stars are relatively bright, which makes it easy to study their planets, so WASP-94 could be used to discover the compositions of the atmospheres of the exoplanets.”
The WASP poll is the most successful search for sexy Jupiter exoplanets which transit–or float in front of–the glaring face of the parent-stars. The WASP-South survey instrument searches the skies every clear night, scanning literally thousands and thousands of sparkling stars for transits. The Belgian team is responsible for picking the best WASP candidates by obtaining high-quality data of transit lightcurves.