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Short solar cycle detected on distant star DR EMILY BALDWIN ASTRONOMY NOW Posted: 27 August 2010 Scientists using the Convection Rotation and Planetary Transits (CoRoT) space mission have uncovered a short solar magnetic cycle on a distant star using stellar seismology. Stellar seismology is a technique used by scientists to 'listen' to the heartbeat of stars, like HD 49933, which is located 100 light years away in the constellation Monoceros. “Essentially, the star is ringing like a bell,” says National Center for Atmospheric Research scientist Travis Metcalfe. “As it moves through its starspot cycle, the tone and volume of the ringing changes in a very specific pattern, moving to higher tones with lower volume at the peak of its magnetic cycle.” ![]() Using CoRoT, scientists have listened to the heartbeat of a distant star using a technique called stellar seismology. Image: Institute of Astrophysics of the Canaries, IAC. Although magnetic cycles have been detected previously in other stars, this is the first time a cycle has been discovered using stellar seismology. Analysing 187 days worth of data the team detected regions of intense magnetic activity like our own star's sunspots. But HD 49933 is much bigger and hotter than our Sun, and its magnetic cycle much shorter – less than a year, the shortest ever observed in another star. The brief cycle will allow astronomers to observe an entire solar sequence much more quickly than stars with longer cycles, such as the Sun's 11-year cycle. As well as helping to learn how magnetic activity varies from star to star, understanding the magnetic environment of other stars could point astronomers in the direction of potentially habitable planets. “Understanding the activity of stars harboring planets is necessary because magnetic conditions on the star’s surface could influence the habitable zone, where life could develop,” says CEA-Saclay scientist Rafael Garcia, the study’s lead author. The team plan to extend their survey by using data from NASA's Kepler mission. “If it turns out that a short magnetic cycle is common in stars, then we will potentially observe a large number of full cycles during Kepler’s mission,” says Metcalfe. “The more stars and complete magnetic cycles we have to observe, the more we can place the Sun into context and explore the impacts of magnetic activity on possible planets hosted by these stars.” Meanwhile, ground-based observations will be used to follow up on CoRoT's observations of HD 49933 when it re-emerges from behind the Sun next month. |
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The Planets
Hubble Reborn
3D Universe
This special publication features the photography of British astro-imager Nik Szymanek and covers a range of photographic methods from basic to advanced. Beautiful pictures of the night sky can be obtained with a simple camera and tripod before tackling more difficult projects, such as guided astrophotography through the telescope and CCD imaging.Starry Night Explore the Universe with these new versions of the award-winning Starry Night Software. Available now from the Astronomy Now Store.Exploring Mars Astronomy Now is pleased to announce the publication of Exploring Mars. The very best images of Mars taken by orbiting spacecraft and NASA's Spirit and Opportunity rovers fill up the 98 glossy pages of this special edition!Mars rover poster This new poster features some of the best pictures from NASA's amazing Mars Exploration Rovers Spirit and Opportunity. |
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