STEREO turns its steady gaze on variable stars

Apr 20, 2011
Image caption: A STEREO/HI-1A image taken on 7th March 2010 (left) with two variable stars highlighted in the image. The varying brightness of the two stars, V837 Tau and V1129 Tau are shown (right top and bottom, respectively). Credit: Image produced by D. Bewsher (UCLan). Data courtesy of NASA/STEREO and the HI instrument team.

(PhysOrg.com) -- Researchers have discovered 122 new eclipsing binary stars and observed hundreds more variable stars in an innovative survey using NASA's two STEREO solar satellites. The survey has been carried out by team from the Open University, University of Central Lancashire and the STFC Rutherford Appleton Laboratory. Dr Danielle Bewsher presented highlights at the RAS National Astronomy Meeting in Llandudno, Wales on Tuesday 19th April.

STEREO was launched in 2006 to study the in 3D and coronal mass ejections, the cause of . Each carries a Heliospheric Imager (HI), each instrument comprising two cameras (HI-1 and HI-2) built and developed at the STFC's Rutherford Appleton Laboratory and the University of Birmingham. The HI cameras are able to make such stable measurements that researchers can accurately monitor the brightness of stars in the background. 
 
"Although STEREO is primarily a solar mission, we recognised that the stability of the HI cameras could also be used to monitor variations of the brightness of stars," said Bewsher, of the University of Central Lancashire. "To date, 893 000 stars have passed through the HI-1 field-of-view alone, producing an unexpected resource of scientific data about the variability of stars that is currently being data mined."
 
The lead author, Karl Wraight, an STFC PhD student at the OU, has found the 122 new eclipsing binaries during an initial analysis of the data, and expects many more to be discovered.
 
"STEREO's ability to sample continuously for up to 20 days, coupled with repeat viewings from the twin spacecraft during the year, makes it an invaluable resource for researching . As well as making discoveries, observations from HI are enabling us to pin down the periods of known variables with much greater accuracy," said Wraight. 
 
In addition to studying variable stars, the team believes that HI measurements may be used for exoplanet and astroseismology research.
 
"Very small changes to the brightnesses of stars can be detected, which could reveal the presence of transiting exoplanets, or be used to trace a star’s internal structure by measuring their seismic activity," said Professor Glenn White (RAL and OU).

Explore further: Magnetar discovered close to supernova remnant Kesteven 79

Related Stories

A New Class of Variable Stars Revealed

Feb 26, 2010

(PhysOrg.com) -- Modern astronomy sometimes makes discoveries by looking in new places, the distant universe for example, using telescopes and instruments that extend the previous limits of detection.

Our Suns fiery outbursts seen in 3D

Jul 17, 2006

UK solar scientists are eagerly awaiting the launch of NASAs STEREO mission which will provide the first ever 3D views of the Sun. STEREO (Solar TErrestrial RElations Observatory) comprises two nearly identical ...

Scientists see solar outburst in exquisite detail

Apr 20, 2011

(PhysOrg.com) -- The largest disturbances to the Earth's geomagnetic environment occur when it is buffeted by solar material hurled in our direction by explosive changes in the Sun's atmosphere. These Coronal ...

Comet McNaught - A First Light Present for STEREO

Jan 19, 2007

This image of Comet McNaught comes from the Heliospheric Imager on one of the STEREO spacecraft, taken Jan. 11, 2007. To the right is the comet nucleus, so bright it saturates the detector creating a bright ...

Recommended for you

How can we find tiny particles in exoplanet atmospheres?

Aug 29, 2014

It may seem like magic, but astronomers have worked out a scheme that will allow them to detect and measure particles ten times smaller than the width of a human hair, even at many light-years distance.  ...

Spitzer telescope witnesses asteroid smashup

Aug 28, 2014

(Phys.org) —NASA's Spitzer Space Telescope has spotted an eruption of dust around a young star, possibly the result of a smashup between large asteroids. This type of collision can eventually lead to the ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

omatumr
3 / 5 (1) Apr 20, 2011
Since the Sun itself is a variable star, the results of this study may interest those who believe Earth's variable climate is linked to cyclic changes in the Sun.