I’ve often stated that planets come in a wide range of sizes but rarely do I find myself stating they come in a wide range of shapes too! The discovery of WASP-107b is a case in point since this planet is the size of Jupiter but only a tenth of its mass. But there’s more… Using the James Webb Space Telescope a team of astronomers have accurately identified that the planet has an east-west asymmetry in its atmosphere, in other words, it’s lopsided. It is tidally locked to the star and on one side, the atmosphere seems to be inflated compared to the other.
Continue reading “Astronomers Find a Strange Lopsided Planet”A New Model Explains How Gas and Ice Giant Planets Can Form Rapidly
The most widely recognized explanation for planet formation is the accretion theory. It states that small particles in a protoplanetary disk accumulate gravitationally and, over time, form larger and larger bodies called planetesimals. Eventually, many planetesimals collide and combine to form even larger bodies. For gas giants, these become the cores that then attract massive amounts of gas over millions of years.
But the accretion theory struggles to explain gas giants that form far from their stars, or the existence of ice giants like Uranus and Neptune.
Continue reading “A New Model Explains How Gas and Ice Giant Planets Can Form Rapidly”Webb Joins the Hunt for Protoplanets
We can’t understand what we can’t clearly see. That fact plagues scientists who study how planets form. Planet formation happens inside a thick, obscuring disk of gas and dust. But when it comes to seeing through that dust to where nascent planets begin to take shape, astronomers have a powerful new tool: the James Webb Space Telescope.
Continue reading “Webb Joins the Hunt for Protoplanets”Improving a 1960s Plan to Explore the Giant Planets
In the 1960s, NASA engineers developed a series of small lifting-body aircraft that could be dropped into the atmosphere of a giant planet, measuring the environment as they glided down. Although it would be a one-way trip to destruction, the form factor would allow a probe to glide around in different atmospheric layers, gathering data and transmitting it back to a parent satellite. An updated version of the 1960s design is being tested at NASA now, and a drop-test flight from a helicopter is scheduled for this month.
Continue reading “Improving a 1960s Plan to Explore the Giant Planets”Whether Saturn's Rings are Young or Old, its Moons are as Ancient as the Planet Itself
Saturn is best known for two things: its iconic ring structures and its large system of natural satellites. Currently, 146 moons and moonlets have been discovered orbiting the ringed giant, 24 of which are regular satellites. These include the seven largest moons, Titan, Rhea, Iapetus, Dione, Tethys, Enceladus, and Mimas, which are icy bodies believed to have interior oceans. In addition, there are unresolved questions about the age of these satellites, with some suspecting that they formed more recently (like Saturn’s rings, which are a few hundred million years old).
To address these questions, an international team of astronomers created a series of high-resolution simulations coupled with improved estimates of Trans-Neptunian Object (TNO) populations. This allowed them to construct a chronology of impacts for Saturn’s most heavily cratered regular satellites – Mimas, Enceladus, Tethys, Dione, and Rhea. This established age limits of 4.1 and 4.4 billion years for all five, with the two innermost moons appearing more youthful than the outer three. These results could have significant implications for our understanding of the formation and tidal evolution of moons in the outer Solar System.
Continue reading “Whether Saturn's Rings are Young or Old, its Moons are as Ancient as the Planet Itself”The Rings of Uranus Shine Bright in Stunning New JWST Image
The James Webb Space Telescope has taken a stunning new image of the ice giant world Uranus. But what stands out most is the dramatic new view of the planet’s rings, which show up as never before with JWST’s infrared eyes.
Instead of being faint and wispy, the rings show up brilliantly. Additionally, bright, luminous features in the planet’s atmosphere show how an extensive storm system at the north pole of this planet getting larger and brighter.
But you’ll also want to see the full-frame image view, which also shows the six largest of Uranus’ 27 known moons. And, as we’ve become accustomed to seeing in JWST images, several distant background galaxies. Yes, every JWST image is a Deep Field!
Continue reading “The Rings of Uranus Shine Bright in Stunning New JWST Image”It's Time For Your Annual Weather Update for the Outer Solar System
A couple times a year, the Hubble Space Telescope turns its powerful gaze on the giant planets in the outer Solar System, studying their cloudtops and weather systems. With the Outer Planet Atmospheres Legacy (OPAL) Program, Hubble provides us with these views and also delivers weather reports on what’s happening. Here’s an updated report and some new images of the stormy surfaces of Jupiter and Uranus.
Continue reading “It's Time For Your Annual Weather Update for the Outer Solar System”TESS Shows That Even Small Stars Can Host Giant Planets
Can low-mass stars play host to giant, Jupiter-sized planets? Theories of planet formation suggest that it’s highly unlikely. But a team of scientists in the UK found that it’s possible, though rare.
Continue reading “TESS Shows That Even Small Stars Can Host Giant Planets”Jupiter's Giant Moons Prevent it From Having Rings Like Saturn
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.
Continue reading “Jupiter's Giant Moons Prevent it From Having Rings Like Saturn”Hubble Has Been Watching This Planet Form for 13 Years
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.
Continue reading “Hubble Has Been Watching This Planet Form for 13 Years”