Skip to main content
  1. Home
  2. Space
  3. Space News

This exoplanet whizzes around its star once a week and is bombarded by flares

By
NASA’s TESS, Spitzer Missions Discover World Orbiting Unique Young Star

Around 32 light-years away from Earth, practically in our backyard, lies a dramatic young star named AU Microscopii or AU Mic for short. This star is just 20 to 30 million years old. This might sound ancient, but by star standards, it’s a baby — for reference, our sun is 150 times older.

Recommended Videos

Orbiting this baby star is a planet of dramatic events, AU Mic b, recently discovered using data from NASA’s Transiting Exoplanet Survey Satellite (TESS) and the now-retired Spitzer Space Telescope.

Related: 
Best new movies to stream on Netflix, Hulu, Prime Video, HBO Max, and more

A year on this Neptune-sized planet lasts just over one Earth week as it orbits extremely close to its star. And it is constantly bombarded with flares from the star, caused by the star’s strong magnetic fields. The star is often covered with starspots — similar to sunspots — which erupt with flares that bathe the planet in radiation.

rendering of the young planet AU Mic b
This rendering of the young planet AU Mic b is part of NASA’s fun-but-informative Galaxy of Horrors poster series. The planet’s star, AU Microscopii, emits powerful, fiery flares that would likely terrorize any lifeforms that tried to make a home here. NASA's Exoplanet Exploration Program

Because the star AU Mic is so young, both it and its planet are still surrounded by the disk of dust and gas from which they formed. That makes this system the ideal place for researchers to observe to understand more about how planetary systems develop over time.

“We think AU Mic b formed far from the star and migrated inward to its current orbit, something that can happen as planets interact gravitationally with a gas disk or with other planets,” coauthor Thomas Barclay, associate project scientist for TESS at NASA’s Goddard Space Flight Center, explained in a statement.

artist's concept shows the dusty disk surrounding the star AU MIcroscopii
This artist’s concept shows the dusty disk surrounding the star AU MIcroscopii. Astronomers have studied this system extensively but only recently identified the presence of a planet there. The find provides a laboratory for studying planet evolution and formation. NASA's Goddard Space Flight Center/Chris Smith (USRA)

Barclay and his team have also compared the system to planets in another nearby system, the Beta Pictoris Moving Group. “By contrast, Beta Pictoris b’s orbit doesn’t appear to have migrated much at all. The differences between these similarly aged systems can tell us a lot about how planets form and migrate,” he said.

There may even be more planets hiding in the orbit of AU Mic, so the scientists will return to this system to study it more and see if they can find them.

“There is an additional candidate transit event seen in the TESS data, and TESS will hopefully revisit AU Mic later this year in its extended mission,” lead researcher Peter Plavchan said. “We are continuing to monitor the star with precise radial velocity measurements, so stay tuned.”

The research is published in the journal Nature.

Georgina Torbet
Georgina Torbet
Space Writer
Georgina has been the space writer at Digital Trends space writer for six years, covering human space exploration, planetary…
Topics

Editors’ Recommendations

Watch the Starliner spacecraft star in its own aurora video
Boeing's Starliner capsule docked at the ISS.

Boeing’s CST-100 Starliner launched successfully atop a United Launch Alliance Atlas V rocket on June 5, safely delivering NASA astronauts Suni Williams and Butch Wilmore to the International Space Station (ISS) the following day.

The Starliner, on its first crewed flight to orbit, was originally scheduled for a stay lasting just over a week. But in recent days, NASA announced the spacecraft would stay at the ISS until June 22 to finalize departure planning and operations, and also to carry out engine tests to evaluate the performance of thrusters, some of which played up during the Starliner’s final approach to the ISS on June 6.

Read more
James Webb observes extremely hot exoplanet with 5,000 mph winds
This artist’s concept shows what the hot gas-giant exoplanet WASP-43 b could look like. WASP-43 b is a Jupiter-sized planet circling a star roughly 280 light-years away, in the constellation Sextans. The planet orbits at a distance of about 1.3 million miles (0.014 astronomical units, or AU), completing one circuit in about 19.5 hours. Because it is so close to its star, WASP-43 b is probably tidally locked: its rotation rate and orbital period are the same, such that one side faces the star at all times.

Astronomers using the James Webb Space Telescope have modeled the weather on a distant exoplanet, revealing winds whipping around the planet at speeds of 5,000 miles per hour.

Researchers looked at exoplanet WASP-43 b, located 280 light-years away. It is a type of exoplanet called a hot Jupiter that is a similar size and mass to Jupiter, but orbits much closer to its star at just 1.3 million miles away, far closer than Mercury is to the sun. It is so close to its star that gravity holds it in place, with one side always facing the star and the other always facing out into space, so that one side (called the dayside) is burning hot and the other side (called the nightside) is much cooler. This temperature difference creates epic winds that whip around the planet's equator.

Read more
How astronomers used James Webb to detect methane in the atmosphere of an exoplanet
An artists rendering of a blue and white exoplanet known as WASP-80 b, set on a star-studded black background. Alternating horizontal layers of cloudy white, grey and blue cover the planets surface. To the right of the planet, a rendering of the chemical methane is depicted with four hydrogen atoms bonded to a central carbon atom, representing methane within the exoplanet's atmosphere. An artist’s rendering of the warm exoplanet WASP-80 b whose color may appear bluish to human eyes due to the lack of high-altitude clouds and the presence of atmospheric methane identified by NASA’s James Webb Space Telescope, similar to the planets Uranus and Neptune in our own solar system.

One of the amazing abilities of the James Webb Space Telescope is not just detecting the presence of far-off planets, but also being able to peer into their atmospheres to see what they are composed of. With previous telescopes, this was extremely difficult to do because they lacked the powerful instruments needed for this kind of analysis, but scientists using Webb recently announced they had made a rare detection of methane in an exoplanet atmosphere.

Scientists studied the planet WASP-80 b using Webb's NIRCam instrument, which is best known as a camera but also has a slitless spectroscopy mode which allows it to split incoming light into different wavelengths. By looking at which wavelengths are missing because they have been absorbed by the target, researchers can tell what an object -- in this case, a planetary atmosphere -- is composed of.

Read more