Nature versus nurture refers to a long-standing debate among scientists trying to figure out whether human behavior is determined by the environment or simply the result of a person’s genes. Planets and people can have a lot in common, and the atmospheres of a duo of hot jupiter exoplanets is one such example. These two worlds serve as examples of how nature vs nurture operates when it comes to these two “cousin” exoplanets. In a first-of-its-kind experiment, planet-hunting astronomers used NASA Hubble Space Telescope (HST) to observe the hot jupiter “cousins,” and because these two distant, gassy, ​​hot worlds are virtually identical in both size and temperature, revolving around their nearly identical parent stars at nearly the same distance, astronomers thought their atmospheres would be similar, too. What they found surprised them: One of these related worlds is cloudier than the other, and the difference between these distant worlds is now a delightful mystery waiting to be solved by curious planetary scientists trying to understand why this difference between the two exists. worlds so closely related.

Lead scientists, Dr. Giovanni Bruno of the Space Telescope Science Institute (STSI) in Baltimore, Maryland, explained on a June 5, 2017 STSI press release that “What we see by looking at the two atmospheres is that they are not the same. One planet, WASP-67b, is cloudier than the other, HAT-P-38b. We don’t see what we see.” is waiting, and we need to understand why we found this difference.

Planetary scientists used HST Wide Field Camera 3 to look at the spectral fingerprints of the two “cousin” exoplanets, which measure the chemical composition. “The effect that clouds have on the spectral signature of water allows us to measure the amount of clouds in the atmosphere. More clouds mean that the characteristic of water is reduced,” added Dr Bruno.

“This tells us that there had to be something in their past that is changing the appearance of these planets,” he continued.

From a historical perspective, the search for distant alien worlds, located within families of stars beyond our own Sun, turned out to be a difficult task. The discovery of the first exoplanets a generation ago clearly represents one of humanity’s greatest achievements. The detection of a giant planet, such as Jupiter, the striped giant in our own Solar System, has been compared to observing light jumping from a mosquito flying in front of a 1000-watt streetlight bulb, when the observer is 10 miles. far.

Discovery

the smaller it is exoplanetthe more difficult it is to discover. For example, if an extraterrestrial astronomer, belonging to a technologically advanced civilization, were to hunt for other planets in remote regions of our Milky Way, it would be difficult for him to find our little planet. This is because our Earth would appear to be just a faint and insignificant speck in the vastness of space. In fact, our planet is very well hidden from nosy alien astronomers because it is overwhelmed by the glare of our Star.

The first detection of an exoplanet occurred in 1988. However, the first confirmed discovery came in 1992, with the detection of some strange and hostile planets revolving around a dense, city-sized stellar corpse called press. pulsars they are the lingering relics of massive stars that have perished in the terrible fury of a supernova explosion. This furious, fatal and final blaze of glory marks the violent and catastrophic end of the star that was.

Astronomers detected the first exoplanet orbiting a still “living” star, like our own Sun, in 1995. However, this landmark discovery left a trail of confusion. The newly discovered alien world, dubbed 51 pegasus bit was unlike anything planetary scientists thought could exist. 51 Pin b is a hot jupiter–a giant gas world, like our Solar System’s Jupiter, closely hugging its parent star in a fiery orbit that is much closer to its stellar parent than Mercury’s orbit around our Sun. Before the discovery of 51 Pin bmost astronomers thought that gas giant planets could only exist much farther from their stars, comparable to the distance from Jupiter to our Sun. Jupiter is located in the cold outer region of our Solar System.

The original technique used by astronomers back in 1995, the Doppler shift method–favors the discovery of giant planets that orbit their parent stars in close, fiery orbits. Tea Doppler shift The method looks for a small wobble induced in a star by an orbiting planet: the bigger the planet, the bigger the wobble, and the easier it is for planet-hunting astronomers to detect.

As of June 1, 2017, 3,610 exoplanets inhabiting 2,704 planetary systems have been discovered, and 610 multiple planetary systems have also been verified. Since 2004, the European Southern Observatory (ESO) High Precision Radial Velocity Planet Finder (HARPS) 3.6-meter telescope, has detected approximately 100 exoplanets, and since 2009, NASA Kepler Space Telescope has discovered more than two thousand. Kepler it has also detected a few thousand candidate planets, of which only about 11% may turn out to be false positives. Planet-seeking astronomers estimate that about 1 in 5 stars similar to our Sun are orbited by an “Earth-sized” planet located in the living area surrounding his star. Tea living area of a star is that Goldilocks region where temperatures are not too hot, not too cold, but just right for water to exist in its life-sustaining liquid phase. Where liquid water exists, life can also potentially evolve. If there are 200 billion stars inhabiting our Galaxy, there may be 11 billion potentially habitable Earth-sized worlds in our Milky Way. This already huge number could be further increased if the planets revolving around the numerous and long-lived red dwarf Stars are included in the estimate. red dwarf The stars are the smallest, coolest and most abundant true stars that inhabit our galaxy. red dwarfs they are even smaller than our little Sun, and can potentially stay on burning hydrogen main stream of the Hertzsprung-Russell diagram of stellar evolution for trillions of years. For this reason, it is generally thought that there is not (yet) red dwarf relics that inhabit the Cosmos. This is because our Universe is a 13.8 billion year old “mother” and not red dwarf has had enough time to die since the Big Bang.

The least massive exoplanet discovered so far is Draugr (PSR B1257+12A Prayed PSR B1257+12B), which weighs only twice the mass of our planet’s Moon. By contrast, the most massive known exoplanet is DENIS-P J082303.11-491201b, and is about 29 times more massive than Jupiter. However, according to some definitions of planet, this extremely large world is too massive to be a planetand it may be a kind of failed star called brown dwarf. brown dwarfs they are relatively small distant worlds that probably form in the same way as their true stellar relatives, but never manage to reach the mass necessary to ignite their stars. nuclear fusion fires. These stellar failures are actually a pretty purple-pink color called magentaand are born as a result of the collapse of a dense bag embedded within the undulating, swirling folds of a cold, giant molecular cloud–just like its more successful stellar relatives.

Some exoplanets stick closely to their parent star in orbits so tight and scorching that they only require a few hours to complete a single orbit. However, there are other alien planets that take thousands of years to go around their star. In fact, some exoplanets are so far from their parent star that it is sometimes very difficult for astronomers to determine whether they are actually gravitationally bound to it. Almost all of the exoplanets discovered so far are inhabitants of our own galaxy, the Milky Way, but there have also been detections of a handful of intriguing, but as yet unconfirmed, extragalactic exoplanets. The closest exoplanet to Earth is called Proxima Centauri bthat circulates Proxima Centaurithe closest star to our Sun. Proxima Centauri b it is “only” 4.2 light-years from Earth.

There is also a large population of so-called rogue planets, which do not belong to the family of any stars at all, but instead roam the wilderness of interstellar space without a parent star to call their own. Alas, these lonely, lonely alien worlds were probably once members of a planetary system, but were abruptly dislodged by gravitational jostling from sister worlds, or by gravitational disruption caused when a traveling star passed too close to its own stellar parent. Astronomers tend to consider these lonely worlds separately, especially if they are gas giant planets. If this is the case, these rogue planets are often classified as sub-brown dwarfs. Tea rogue planets that roam our Milky Way may number in the billions.

Nature versus nurture: The Strange Case Of The Exoplanet “Cousins”

The two mismatched “cousin” exoplanets, one cloudy and one clear, orbit their yellow dwarf stars once every 4.5 Earth days. Both exoplanets hug their parent star tightly, much more than Mercury hugs our Sun. Long ago, though, the planets probably migrated inward toward the dazzling fires and scorching heat of their stellar parent from the outer regions. more distant from where they were born.

One planet may have formed differently than another as a result of a different set of circumstances. “You can say it’s nature versus nurture. Right now, they appear to have the same physical properties. So if their measured composition is defined by their current state, then it should be the same for both planets. But that’s not the case. Instead, it appears their training histories may be playing a role,” study co-investigator Dr. Kevin Stevenson explained June 5, 2017, in The STSI press release.

The clouds of this distant duo of Jupiter-like gas giants are not like the clouds we see on Earth. Instead, these very strange clouds are probably alkaline clouds. This means that they are probably made up of molecules like sodium sulfide and potassium chloride. The average temperature on each of these grilled planets is over 1,300 degrees Fahrenheit.

The two exoplanets are also tidally locked. This means that they always show the same side in front of their star parent. The two worlds have an extremely hot day side and a cooler night side.

The team of astronomers has just begun to learn what factors are important for some exoplanets to be cloudy, in contrast to others that are clear. To gain a better understanding of what the planets’ mysterious past may have been like, scientists will need future observations with the HST and the next to be released James Webb Space Telescope.

The team’s results were presented June 5, 2017, at the 230th meeting of the American Astronomical Society in Austin, Texas.