. 24/7 Space News .
Searching for Earth 2 zoom in on a star
by Jim Shelton for Yale News
New Haven CT (SPX) Oct 28, 2021

Reconstructed surface of the spotted star Epsilon Eridani with each panel showing the star advanced one-fifth of its rotation. (Visualization by Sam Cabot)

Astronomers searching for Earth-like planets in other solar systems have made a breakthrough by taking a closer look at the surface of stars.

A new technique developed by an international team of researchers - led by Yale astronomers Rachael Roettenbacher, Sam Cabot, and Debra Fischer - uses a combination of data from ground-based and orbiting telescopes to distinguish between light signals coming from stars and signals coming from planets orbiting those stars.

A study detailing the discovery has been accepted by The Astronomical Journal.

"Our techniques pull together three different types of contemporaneous observations to focus on understanding the star and what its surface looks like," said Roettenbacher, a 51 Pegasi b postdoctoral fellow at Yale and lead author of the paper. "From one of the data sets, we create a map of the surface that allows us to reveal more detail in the radial velocity data as we search for signals from small planets.

"This procedure shows the value of obtaining multiple types of observation at once."

For decades, astronomers have used a method called radial velocity as one way to look for exoplanets in other solar systems. Radial velocity refers to the motion of a star along an observer's sightline.

Astronomers look for variations in a star's velocity that might be caused by the gravitational pull of an orbiting planet. This data comes via spectrometers - instruments that look at light being emitted by a star and stretch the light into a spectrum of frequencies that can be analyzed.

As astronomers have rushed to develop methods for detecting Earth-like planets, however, they have run into a barrier that has stopped progress for years. The energy emitted by stars creates a boiling cauldron of convecting plasma that distorts measurements of radial velocity, obscuring signals from small, rocky planets.

But a new generation of advanced instruments is attacking this problem. These instruments include the EXtreme PREcision Spectrograph (EXPRES), which was designed and built by Fischer's team at Yale, the Transiting Exoplanet Survey Satellite (TESS), and the Center for High Angular Resolution Astronomy (CHARA) interferometric telescope array.

For the new study, the researchers used TESS data to reconstruct the surface of Epsilon Eridani, a star in the southern constellation of Eridanus that is visible from most of Earth's surface. They then looked for starspots - cooler regions on the surface of a star caused by strong magnetic fields.

"With the reconstructions, you know the locations and sizes of spots on the star, and you also know how quickly the star rotates," said Cabot. "We developed a method that then tells you what kind of signal you would see with a spectrometer."

The researchers then compared their TESS reconstructions with EXPRES spectrometer data collected simultaneously from Epsilon Eridani.

"This allowed us to directly tie contributions of the radial velocity signature to specific features on the surface," Fischer said. "The radial velocities from the starspots match up beautifully with the data from EXPRES."

The researchers also used another technique, called interferometry, to detect a starspot on Epsilon Eridani - the first interferometric detection of a starspot on a star similar to the Sun.

Interferometry combines separated telescopes to create a much larger telescope. For this, the researchers used the CHARA Array, the world's largest optical interferometer, located in California.

Roettenbacher said she and her colleagues will apply their new technique to sets of interferometric observations in order to directly image the entire surface of a star and determine its radial velocity contribution.

"Interferometric imaging is not something that is done for a lot of stars because the star needs to be nearby and bright. There are a handful of other stars on which we can also apply our pioneering approach," Roettenbacher said.

Former Yale researchers Lily Zhao, who is now at the Flatiron Institute, and John Brewer, who is now at San Francisco State University, are among the study's co-authors.

The research was supported by the Heising-Simons Foundation, an anonymous Yale alumnus, the National Science Foundation, and NASA.

Related Links
Yale University
Lands Beyond Beyond - extra solar planets - news and science
Life Beyond Earth

Thanks for being there;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Monthly Supporter
$5+ Billed Monthly

paypal only
SpaceDaily Contributor
$5 Billed Once

credit card or paypal

How to find hidden oceans on distant worlds? use chemistry
Pasadena CA (SPX) Oct 28, 2021
A new study shows how the chemicals in an exoplanet's atmosphere can, in some cases, reveal whether or not the temperature on its surface is too hot for liquid water. In our solar system, planets are either small and rocky (like Earth) or large and gaseous (like Neptune). But around other stars, astronomers have found planets that fall in between - worlds slightly larger than Earth but smaller than Neptune. These planets may have rocky surfaces or liquid-water oceans, but most are likely to be top ... read more

Comment using your Disqus, Facebook, Google or Twitter login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

NASA, SpaceX Reviewing Commercial Crew Rotation Plans

Mind the stars

NASA could return astronauts on space station before replacements arrive

New roles, combined offices for NASA Administrator Leadership Team

Hypersonix to use Siemens' software in design of its hydrogen fuelled launchers

NASA prepares to fuel James Webb telescope for Dec. 18 launch

Major Artemis engine part arrives at Stennis for certification testing

NASA, SpaceX reschedule Crew-3 launch due to weather

Researchers begin to understand correlation of schumann resonances and dust storms on Mars

UNI Bremen involved in AMADEE-20 Mars Simulation

New Curtin study pinpoints likely home of Martian meteorites

Sol 3285: Oh So Close

Chinese astronauts arrive at space station for longest mission

China's longest-yet crewed space mission impressive, expert says

Chinese astronaut bridges gender gap

Test conducted to verify spacecraft technology, FM says

iRocket And Turion Space ink agreement for 10 launches to low earth orbit

BT secures industry first Global Partnership with OneWeb

Geraldine Naja, Director of Commercialisation, Industry and Procurement

SpaceFund Invests in Rhea Space Activity

Georgia State University astronomy researcher wins grant to improve detection, monitoring of satellites

Simulations in 3D improve understanding of energetic-particle radiation and help protect space assets

VR technology enables users to see individual cells in human body

Shape-shifting materials with infinite possibilities

To find life on other planets, NASA rocket team looks to the stars

Rocky Exoplanets Are Even Stranger Than We Thought

Searching for Earth 2 zoom in on a star

Building planets from protoplanetary disks

Science results offer first 3D view of Jupiter's atmosphere

Juno peers deep into Jupiter's colorful belts and zones

Scientists find strange black 'superionic ice' that could exist inside other planets

Jupiter's Great Red Spot is deeper than thought, shaped like lens

The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.