exoplanets Archives

June 18, 2021June 18, 2021 by Matt Williams

A New Technique for “Seeing” Exoplanet Surfaces Based on the Content of their Atmospheres

This artist’s impression shows the planet K2-18b, it’s host star and an accompanying planet in this system. K2-18b is now the only super-Earth exoplanet known to host both water and temperatures that could support life. UCL researchers used archive data from 2016 and 2017 captured by the NASA/ESA Hubble Space Telescope and developed open-source algorithms to analyse the starlight filtered through K2-18b’s atmosphere. The results revealed the molecular signature of water vapour, also indicating the presence of hydrogen and helium in the planet’s atmosphere.

In November of 2021, the James Webb Space Telescope (JWST) will make its long-awaited journey to space. This next-generation observatory will observe the cosmos using its advanced infrared suite and reveal many never-before-seen things. By 2024, it will be joined the Nancy Grace Roman Space Telescope (RST), the successor to the Hubble mission that will have 100 times Hubble’s field of view and faster observing time.

These instruments will make huge contributions to many fields of research, not the least of which is the discovery and characterization of extrasolar planets. But even with their advanced optics and capabilities, these missions will not be able to examine the surfaces of exoplanets in any detail. However, a team of the UC Santa Cruz (UCSC) and the Space Science Institute (SSI) have developed the next best thing: a tool for detecting an exoplanet surface without directly seeing it.

June 13, 2021June 13, 2021 by Andy Tomaswick

What’s the Connection Between the Chemistry of a Star and the Formation of its Planets?

Scientists seem to have come up with a new parlor game – how many ways can we potentially detect exoplanets? The two most common methods, the transit method and the Doppler method, each have their own problems. Alternative methods are starting to sprout up, and a new one was recently proposed by Jacob Nibauer, an undergraduate student in the University of Pennsylvania’s Department of Physics and Astronomy. His suggestion: look at a star’s chemical composition. And his findings after analyzing data on some 1,500 stars hold some surprises.

May 26, 2021May 26, 2021 by Matt Williams

The Elements for Life Depend on Both how and Where a Planet Forms

Artist's conception of a solar system in formation. It's likely that exoplanet formation around other stars proceeded similarly. Credit: NASA/FUSE/Lynette Cook

In the past few decades, the number of planets discovered beyond our Solar System has grown into the thousands. At present, 4,389 exoplanets have been confirmed in 3,260 systems, with another 5,941 candidates awaiting confirmation. Thanks to numerous follow-up observations and studies, scientists have learned a great deal about the types of planets that exist in our Universe, how planets form, and how they evolve.

A key consideration in all of this is how planets become (and remain) habitable over time. In general, astrobiologists have operated under the assumption that habitability comes down to where a planet orbits within a system – within its parent star’s habitable zone (HZ). However, new research by a team from Rice University, indicates that where a planet forms in its respective star system could be just as important.

May 20, 2021May 20, 2021 by Scott Alan Johnston

Larger Rocky Planets Might be Rare Because They Shrunk

Researchers at the Flatiron Institute’s Center for Computational Astrophysics published a paper last week that just might explain a mysterious gap in planet sizes beyond our solar system. Planets between 1.5 and 2 times Earth’s radius are strikingly rare. This new research suggests that the reason might be because planets slightly larger than this, called mini-Neptunes, lose their atmospheres over time, shrinking to become ‘super-Earths’ only slightly larger than our home planet. These changing planets only briefly have a radius the right size to fill the gap, quickly shrinking beyond it. The implication for planetary science is exciting, as it affirms that planets are not static objects, but evolving and dynamic worlds.

May 15, 2021May 10, 2021 by Paul M. Sutter

Hydroxyl (OH) Seen for the First Time in an Exoplanet Atmosphere

Artist's concept of a hot Jupiter exoplanet orbiting a star similar to tau Boötes (Image used with permission of David Aguilar, Harvard-Smithsonian Center for Astrophysics)

The molecule hydroxyl (HO) is common on Earth, but astronomers have not yet determined how abundant it is on other worlds. For the first time, astronomers have conclusively detected it in the atmosphere of an ultra-hot Jupiter, WASP-33b.

May 5, 2021May 5, 2021 by Brian Koberlein

Dark Matter Could Change the Temperature of Exoplanets, Allowing us to Detect it

Artist view of a Jupiter-like exoplanet. Credit: NASA/Goddard Space Flight Center/S. Wiessinger

Ah, dark matter, you continue to allude us. The stuff is incredibly difficult to study. It doesn’t interact with light, so our evidence of it is based upon its gravitational effects on light and visible matter. And the biggest difficulty is that we still don’t know what it is. Efforts to detect dark matter directly have come up empty, as have indirect methods such as looking for evidence of dark matter through things such as excess gamma-rays in the Milky Way. But astronomers continue to think up new ways to detect the stuff, such as a recent study published in Physical Review Letters.

May 3, 2021May 3, 2021 by Andy Tomaswick

Astronomers are Watching a gas Giant Grow, Right in Front of Their Eyes

In the vastness of space, astronomers are likely to find instances of almost every astronomical phenomena if they look hard enough. Many planetary phenomena are starting to come into sharper focus as the astronomy community continues to focus on finding exoplanets. Now a team led by Yifan Zhou at UT Austin has directly imaged a gas giant still in formation.

April 22, 2021April 22, 2021 by Andy Tomaswick

Giant Planet is Found at an Extreme Distance From its Star

One of the best things about the sheer number of exoplanets that astronomers are currently finding is how some are just very different. Those differences can sometimes undermine standing theories, and prompt scientists to start considering new theories that account for the new information. That is undoubtedly what will happen to accommodate a new massive planet found by a team led by Dutch scientists. This planet is unique in one very special way – it is about 110 times farther away from its star than the Earth is from the sun.

April 12, 2021April 12, 2021 by Brian Koberlein

Brown Dwarfs can Spin so Fast They Almost Tear Themselves Apart

Comparing the rotation of a brown dwarf with Jupiter and Saturn. Credit: Robert Hurt (IPAC/Caltech)

We tend to image planets as spheres. Held together by gravity, the material of a planet compresses and shifts until gravity and pressure reach a balance point known as hydrostatic equilibrium. Hydrostatic equilibrium is one of the defining characteristics of a planet. If a planet were stationary and of uniform density, then at equilibrium, it would be a perfect sphere. But planets rotate, and so even the largest planets aren’t a perfect sphere.

April 9, 2021April 9, 2021 by Scott Alan Johnston

Jupiter Could Make an Ideal Dark Matter Detector

NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill (wikimedia commons)

So, you want to find dark matter, but you don’t know where to look? A giant planet might be exactly the kind of particle detector you need! Luckily, our solar system just happens to have a couple of them available, and the biggest and closest is Jupiter. Researchers Rebecca Leane (Stanford) and Tim Linden (Stockholm) released a paper this week describing how the gas giant just might hold the key to finding the elusive dark matter.