The universe is like a box of chocolates. Each discovery excites both academia and the imagination, but the most exciting is still behind the scenes. And each initially unthinkable star, planet or meteor shows how little we really know about the universe.
A new type of storm … on a star
NASA's Spitzer and Kepler telescopes are a powerful tandem that recently found a completely unexpected phenomenon on a small star: a storm.
Just 53 light-years away in the constellation Lyra, a Jupiter-sized L dwarf named W1906 + 40 showed a strange spot similar to Jupiter's red spot. Unlike its similarly sized brown dwarf cousin, W1906 + 40 is a bona fide star that produces its own light. However, it is difficult to call it light: this tiny stellar object is relatively cold - only 2000 degrees Celsius.
W1906 + 40 is so warm (in the sense: not hot and not cold) that clouds form and swirl in its atmosphere. Fueled by the star's inner fury, these clouds have created a dark spot near the north pole, which astronomers have mistaken for a sunspot. Although it cannot be seen directly, scientists have identified its presence by a blackout that occurs every nine hours.
Cloudy conditions have also been observed on brown dwarfs, but these understars are not strong enough to support fusion. The longest storms on their surface are unlikely to last more than a day. The storm on W1906 + 40 is strong even after two years.
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New mysterious globular cluster
Globular clusters are spherical collections of thousands of stars. Some of them are comparable to the age of the universe; some of them traveled for billions of years before settling on the outskirts of the formed galaxies.
Our Milky Way is large, but has only 150 clusters at its disposal. More massive galaxies attract more clusters, and the closest galactic monster, Centaurus A (NGC 5128), an elliptical galaxy 12 million light-years away, has 2,000 globular hangers-on.
But not all of the Centaurus A clusters are interesting. As a rule, the mass of the cluster is commensurate with its brightness, and the brightest sources are also the most massive. But in the process of studying 125 clusters in Centauri A, astronomers have found that some have much more mass than we see.
Scientists have proposed two equally interesting solutions: dark matter or black holes. Globular clusters do not often contain dark matter, unlike galaxies, but these few may have obtained it using an incomprehensible mechanism. Black holes are also massive enough to produce the observed effect. If so, Centaurus A becomes a cosmic minefield with eerie, voracious black holes in the periphery.
New brightest supernova
The Ohio State University observatory, the formidable All Sky Automated Survey for SuperNovae (ASAS-SN, which stands for "assassin," "automatic survey of the entire sky for supernovae") recently discovered the most ridiculous death of a star ever observed.
In 2015, the double telescopic array Brutus and Cassius stumbled upon an unremarkable spot of light. Subsequent observations revealed a strange spectrum of light emanating from the indicated location, and finally the South African Large Telescope confirmed a cloud of extremely bright gas with an unidentified 15 km object in the center. Scientists suspect that this is a former supernova, several times breaking the previous record - so wild that it released 600 billion suns into the universe.
ASASSN-15lh, as it has been called, is so gorgeous that it goes beyond our scientific understanding. Astronomers cannot properly explain the strength of this supernova, but they have several ideas. Perhaps this is the wild agony of one of the most massive stars in the universe. It turns out that these elite stars exist, it's just that we, perhaps, have not seen one yet.
Likewise, a millisecond magnetar can be used as an explanation. These objects are rotating at incredible speed. If you convert this huge rotational energy into light, you can get exactly the kind of explosion that astronomers have observed.
A new type of star music
Astronomers track down the oldest stars in the galaxy, and a recently updated method has allowed them to locate an ancient group of stars from the early days of the Milky Way.
The study, conducted by the School of Physics and Astronomy at the University of Birmingham, made it possible to peer into the hearts of eight elderly stars living in the globular cluster Messier 4 (M4) some 7,200 light years away and hear music inside. These stars are much older, thicker and redder than the Sun, and (most surprisingly) are filled with sound. These "resonant acoustic vibrations" disturb the stellar matrix and cause tiny but detectable changes in brightness.
The recently invented ability to measure these vibrations has spawned the field of astroseismology, another way to study stars. Astronomers can use this technique to determine the age and mass of a star. These fluctuations confirmed theoretical calculations and showed that M4 stars are 13 billion years old. They are the oldest stars in the galaxy.
A new type of stars with an oxygen atmosphere
The star SDSSJ124043.01 + 671034.68 ("Dox", as it is called for short) is similar to any other star, with a few but: its name is difficult to pronounce and its outer layer is 99.9% oxygen. This incredible white dwarf star is unique in our catalog of 4.5 million stars, including 32,000 confirmed white dwarfs.
The story of its discovery is also noteworthy. Looking for notable stars, scientists study spectral plots that reflect the elemental composition of a star. Unfortunately, strangeness is a human concept, so strangeness has to be detected by eye, machines cannot be trusted. This particular case was noticed by student Gustavo Orici, who scanned about 300,000 spectral diagrams, several thousand a day, before finding Dox.
Typically, white dwarfs are covered in light volatile elements that are produced during the star's life cycle. But Dox somehow surrounded itself with a fluffy shroud and acquired an atmosphere of almost pure oxygen, flavored with a small pinch of other elements like neon and magnesium.
Scientists have no idea how this happened, but they speculate that Dox was once the companion of the red giant. He passed the substance in the form of super-hot gas to his stellar consort, until Dox ate too much, the lid exploded and all the light material went into deep space.
New type of space mountains
Jupiter's eternally lava-erupting moon Io is the most volcanically active body in the solar system. It orbits just 400,000 kilometers from its pot-bellied, gaseous folder, and powerful gravitational forces chew on the moon like chewing gum.
Thanks to countless cycles of gravitational gnawing, Io is now dotted with sulfur geysers, hellish lava flows and jagged mountains. This hundred mountains are unlike any other in the solar system: they exist in isolation and stick right out of the shaky surface of the satellite, unlike the clustered and sloping mountains on other worlds.
As simulations show, compressive forces work in conjunction with lava flows to produce these strange vertical mountains. Io's surface is constantly covered with fresh lava from its 400 active volcanoes (surprising for a body the size of the moon), which cover the moon's plains with five inches of molten matter every ten years.
Ash and lava accumulations create extreme pressures that increase with depth due to the spherical nature of (most) moons. When the stress becomes unbearable, the ground cracks and a massive peak is ejected.
A new type of unexpectedly young hot Jupiter
Hot Jupiters are gas giants that have somehow ended up close to their stars. Some of them are trapped in such tight orbits that the star's gravity eats away small bodies layer by layer, and the possible planet PTFO8-8695 b orbits so close that it completes its orbit every 11 hours.
PTFO8-8695 b is also one of the youngest planets, as its star, PTFO8-8695, is only two million years old. This is paradoxically small - most hot Jupiters are billions of years old around stars.
Astronomers think that all hot Jupiters migrate because it is too hot near the star for gas giants to form. Gas planets coalesce in quiet, cool conditions; likewise, the giants in our solar system are located behind the asteroid belt.
The fate of PTFO8-8695 b is unknown, but not so pessimistic. It looks like some hot Jupiters are settling in stable orbits and could possibly survive long enough.
A new type of extinct space rocks
Oest 65, an ancient space stone rich in iridium and neon, is unlike any other in our collection of 50,000 space mementos. He belongs to the type of meteorites that we may never see again, as according to astronomers, the brutal collision in the process of which Oest 65 appeared, ground his parent bodies into powder.
This meteorite fell 470 million years ago and settled in the lower part of the ancient ocean, which is now part of a Swedish quarry. His parent was, most likely, a space potato 20-30 kilometers wide, big enough to grab a good piece of the Earth, when compared with the relatively frail asteroid Chicxulub, which destroyed the dinosaurs (10 kilometers).
The orbital potato collided with an even more gigantic space rock, 100-150 kilometers wide, spawning many small pieces that violently hit the Earth. These chondrites still wander around the Sun, although we will probably never find a sample similar to Oest 65.
A new type of exosystem
When astronomers discovered the planet 2MASS J2126-814, it looked like a world existing completely separate, in itself. This planet, a wandering gas giant 12-14 times more massive than Jupiter, is doomed to forever wander through space in search of a sun to call its own.
But this story has a happy ending. Astronomers have found another object next to the outcast planet, a red dwarf named TYC 9486-927-1. Both bodies are 100 light-years from Earth and seem to be moving together - it turns out that the planet is not at all alone.
Scientists realized they had discovered the largest solar system known to date. The parent star is located 1,000,000,000,000 kilometers from the planet. What it is like - imagine life forms that gaze into the night sky and cannot distinguish their own star from other similar points in the sky.
2MASS J2126-8140 orbits 140 times the size of Pluto, which is 6 billion kilometers from the Sun. Such a situation could not result from the traditional method of birth of the solar system in the process of disk collapse, and scientists believe that these two bodies emerged from one giant trickle of intergalactic gas.
A new type of solid planet
Rigid planets like Earth are subject to mass restrictions. If one grows too thick, its gravitational pull attracts more and more hydrogen and swells into a gas giant. Usually so. But the planet Kepler-10c, with a mass of 17 Earths and no gas, is showing astronomers zero.
They discovered this planet floating 560 light years in the constellation Draco using the Kepler space observatory in conjunction with Telescopio Nazionale Galileo in the Canary Islands. Kepler-10c - 30,000 kilometers in diameter - was originally thought to be a funny-sized gas giant - mini-neptune - relatively small planets with dense layers of gas.
But the mini-neptune hypothesis was dissolved when mass measurements showed that Kepler-10c somehow managed to squeeze 17 Earth's masses within this framework. For a mini-neptune, this is too "fleshy" and suggests that the planet is composed of solids.
Kepler-10c, with its age of 11 billion years, is a cosmic long-liver. Her advanced age suggests that there were many heavy elements lurking in the early universe, and increases the likelihood that space contains many more rocky planets than previously thought.
ILYA KHEL