Exoplanets Archives

May 22, 2020May 22, 2020 by Evan Gough

Ocean Circulation Might Be the Key to Finding Habitable Exoplanets

Artist's depiction of a waterworld. A new study suggests that Earth is in a minority when it comes to planets, and that most habitable planets may be greater than 90% ocean. Credit: David A. Aguilar (CfA)

We’ve found thousands and thousands of exoplanets now. And spacecraft like TESS will likely find thousands and thousands more of them. But most exoplanets are gassy giants, molten hell-holes, or frozen wastes. How can we find those needles-in-the-haystack habitable worlds that may be out there? How can we narrow our search?

Well, first of all, we need to find water. Oceans, preferably, since that’s where life began on Earth. And according to a new study, those oceans need to circulate in particular ways to support life.

May 21, 2020May 21, 2020 by Evan Gough

Astronomers Are Sure These Are Two Newborn Planets Orbiting a Distant Star

An artist's illustration of the PDS 70 system, not to scale. The two planets are clearing a gap in the circumstellar disk as they form. As they accrete in-falling material, the heat makes them glow. Image Credit: W. M. Keck Observatory/Adam Makarenko

Planet formation is a notoriously difficult thing to observe. Nascent planets are ensconced inside dusty wombs that resist our best observation efforts. But recently, astronomers have made progress in imaging these planetary newborns.

A new study presents the first-ever direct images of twin baby planets forming around their star.

May 7, 2020May 7, 2020 by Evan Gough

More Pictures of Planet-Forming Disks Around Young Stars

The fifteen images of protoplanetary disks, captured with ESO's Very Large Telescope Interferometer. CREDIT Jacques Kluska et al.

Astronomy is advancing to the point where we can see planets forming around young stars. This was an unthinkable development only a few years ago. In fact, it was only two years ago that astronomers captured the first image of a newly-forming planet.

Now there are more and more studies into how planets form, including a new one with fifteen images of planet-forming disks around young stars.

May 5, 2020May 5, 2020 by Evan Gough

Astronomers Find a Planet With Three Times the Mass of Jupiter

Astronomers have discovered the exoplanet Kepler-88 d, a planet three times more massive than Jupiter. Illustration Credit: W. M. KECK OBSERVATORY/ADAM MAKARENKO

Jupiter is the Boss.

Well, in terms of planets in our Solar System it is. It’s played a huge role in shaping the Solar System due to its mass and its gravity. Here’s a few ways it’s shaped our system:

May 5, 2020May 5, 2020 by Evan Gough

Worlds With Hydrogen in Their Atmospheres Could Be the Perfect Place to Search for Life

Artist's impression of the exoplanet GJ 1132 b, which orbits the red dwarf star GJ 1132. Astronomers have managed to detect the atmosphere of this Earth-like planet. Credit: MPIA

We’re waiting patiently for telescopes like the James Webb Space Telescope to see first light, and one of the reasons is its ability to study the atmospheres of exoplanets. The idea is to look for biosignatures: things like oxygen and methane. But a new study says that exoplanets with hydrogen in their atmospheres are a good place to seek out alien life.

May 1, 2020May 1, 2020 by Evan Gough

Rocky Planets Orbiting White Dwarf Stars Could be the Perfect Places to Search for Life

Artist's rendition of a white dwarf from the surface of an orbiting exoplanet. Astronomers have found two giant planet candidates orbiting two white dwarfs. More proof that giant planets can surve their stars' red giant phases. Image Credit: Madden/Cornell University

Some very powerful telescopes will see first light in the near future. One of them is the long-awaited James Webb Space Telescope (JWST.) One of JWST’s roles—and the role of the other upcoming ‘scopes as well—is to look for biosignatures in the atmospheres of exoplanets. Now a new study is showing that finding those biosignatures on exoplanets that orbit white dwarf stars might give us our best chance to find them.

April 7, 2020April 7, 2020 by Evan Gough

Astronomers Watched a Star System Die

This is an artist’s impression of a white dwarf (burned-out) star accreting rocky debris left behind by the star’s surviving planetary system. It was observed by Hubble in the Hyades star cluster. At lower right, an asteroid can be seen falling toward a Saturn-like disk of dust that is encircling the dead star. Infalling asteroids pollute the white dwarf’s atmosphere with silicon. Credit: NASA, ESA, and G. Bacon (STScI)

About 570 light years from Earth lies WD 1145+017, a white dwarf star. In many respects it’s a typical white dwarf star. Its mass is about 0.6 solar masses, and its temperature is about 15,900 Kelvin. But five years ago, a team of astronomers wrote a paper on the white dwarf, showing that something unusual was going on.

April 2, 2020April 2, 2020 by Evan Gough

Astronomers Define the “Really Habitable Zone”. Planets Capable of Producing Gin and Tonic

Gin and tonic. Image Credit: By NotFromUtrecht - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=8529628

A hospitable star that doesn’t kill you with deadly flares. A rocky planet with liquid water and an agreeable climate. Absence of apocalyptic asteroid storms. No pantheon of angry, vengeful, and capricious gods. These are the things that define a habitable planet.

Now some scientists are adding one more criterion to the list: gin and tonic.

March 12, 2020March 12, 2020 by Evan Gough

Your Umbrella is Insufficient on a Planet Where it Rains Iron

Work by the Geneva cartoonist Frederik Peeters: «Singing in the Iron Rain: An Evening on WASP-76b». (Detail - © Frederik Peeters)

Imagine a planet where it rained iron. Sounds impossible. But on one distant exoplanet, which is tidally locked to its star, the nightside has to contend with a ferrous downpour.

March 4, 2020March 4, 2020 by Evan Gough

Are Low Density “Cotton Candy” Exoplanets Actually Just Regular Planets With Rings?

An artist’s conception of Piro and Vissapragada’s model of a ringed planet transiting in front of its host star. They used these models to constrain which of the known super-puffs could be explained by rings. Illustration is by Robin Dienel and courtesy of the Carnegie Institution for Science.

There’s a type of exoplanet that astronomers sometimes refer to as cotton candy planets, or super-puffs. They’re mysterious, because their masses don’t match up with their extremely large radii. The two characteristics imply a planet with an extremely low density.

In our Solar System, there’s nothing like them, and finding them in distant solar systems has been puzzling. Now a pair of astronomers might have figured it out.