When the name Saturn is uttered, what comes to mind? For most people, the answer would probably be, “its fabulous system of rings.” There’s no doubt they are iconic, but what is perhaps lesser-known is that Jupiter, Uranus, and Neptune all have ring systems of their own. However, whereas Saturn’s rings are composed mainly of ice particles (making them highly reflective), Jupiter’s rings are composed mainly of dust grains. Meanwhile, Uranus and Neptune have rings of extremely dark particles known as tholins that are very hard to see. For this reason, none of the other gas giants get much recognition for their rings.
However, the question of why Jupiter doesn’t have larger, more spectacular rings than Saturn has been bothering astronomers for quite some time. As the larger and more massive of the two bodies, Jupiter should have rings that would dwarf Saturn’s by comparison. This mystery may have finally been resolved thanks to new research by a team from UC Riverside. According to their study, Jupiter’s massive moons (aka. Jupiter’s Galilean Moons) prevented it from developing a big, bright, beautiful ring system that would put Saturn’s to shame.
Hubble’s most remarkable feature might be its longevity. The Hubble has been operating for almost 32 years and has fed us a consistent diet of science—and eye candy—during that time. For 13 of its 32 years, it’s been checking in on a protoplanet forming in a young solar system about 530 light-years away.
Planet formation is always a messy process. But in this case, the planet’s formation is an “intense and violent process,” according to the authors of a new study.
Astronomers have spied three more exoplanets. But the discovery might not last long. Each planet is in a separate solar system, and each orbits perilously close to its star. Even worse, all of the stars are dying.
Next time you want to be the life of the party—if you’re hanging out with cool nerds that is—just drop that phrase into the conversation. And when they look at you quizzically, just say that’s the eventual fate of the Solar System.
Thanks to the success of the Kepler mission, we know that there are multitudes of exoplanets of a type called “Hot Jupiters.” These are gas giants that orbit so close to their stars that they reach extremely high temperatures. They also have exotic atmospheres, and those atmospheres contain a lot of strangeness, like clouds made of aluminum oxide, and titanium rain.
A team of astronomers has created a cloud atlas for Hot Jupiters, detailing which type of clouds and atmospheres we’ll see when we observe different Hot Jupiters.
M-type (red dwarf) stars are cooler, low-mass, low-luminosity objects that make up the vast majority of stars in our Universe – accounting for 85% of stars in the Milky Way galaxy alone. In recent years, these stars have proven to be a treasure trove for exoplanet hunters, with multiple terrestrial (aka. Earth-like) planets confirmed around the Solar System’s nearest red dwarfs.
But what is even more surprising is the fact that some red dwarfs have been found to have planets that are comparable in size and mass to Jupiter orbiting them. A new study conducted by a team of researchers from the University of Central Lancashire (UCLan) has addressed the mystery of how this could be happening. In essence, their work shows that gas giants only take a few thousand years to form.
The study of extrasolar planets has really exploded in recent years. Currently, astronomers have been able to confirm the existence of 4,104 planets beyond our Solar System, with another 4900 awaiting confirmation. The study of these many planets has revealed things about the range of possible planets in our Universe and taught us that there are many for which there are no analogs in our Solar System.
For example, thanks to new data obtained by the Hubble Space Telescope, astronomers have learned more about a new class of exoplanet known as “super-puff” planets. Planets in this class are essentially young gas giants that are comparable in size to Jupiter but have masses that are just a few times greater than that of Earth. This results in their atmospheres having the density of cotton candy, hence the delightful nickname!
Thanks to the Kepler mission and other efforts to find exoplanets, we’ve learned a lot about the exoplanet population. We know that we’re likely to find super-Earths and Neptune-mass exoplanets orbiting low-mass stars, while larger planets are found around more massive stars. This lines up well with the core accretion theory of planetary formation.
But not all of our observations comply with that theory. The discovery of a Jupiter-like planet orbiting a small red dwarf means our understanding of planetary formation might not be as clear as we thought. A second theory of planetary formation, called the disk instability theory, might explain this surprising discovery.
Scientists have long speculated that at the heart of a gas giant, the laws of material physics undergo some radical changes. In these kinds of extreme pressure environments, hydrogen gas is compressed to the point that it actually becomes a metal. For years, scientists have been looking for a way to create metallic hydrogen synthetically because of the endless applications it would offer.
At present, the only known way to do this is to compress hydrogen atoms using a diamond anvil until they change their state. And after decades of attempts (and 80 years since it was first theorized), a team of French scientists may have finally created metallic hydrogen in a laboratory setting. While there is plenty of skepticism, there are many in scientific community who believe this latest claim could be true.