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Recent Activity

Variable Star Observations in Database:

32,770,045 and Counting ...
Last Observation Received:

2 min 30 sec ago by TRT - Tamas Tordai (HU)

OV BOO   Mar 25.9883   13.604V   

Plot OV BOO light curve


Stellar News Feed

The Secret (X-Ray) Lives of Cepheids: The Surprising Discovery of a New Class of Pulsating X-Ray Stars

Data recently returned for d Cep from the Chandra X-ray Observatory, combined with previous X-ray measures secured with the XMM-Newton X-ray satellite, have shown that d Cep has X-ray variations occurring in accord with the supergiant star's 5.4 day pulsation period. X-rays are observed at all phases of the star’s pulsations, but sharply rise by ~400% near the times when the star swells to its maximum diameter of about 45 times that of the Sun.

New types of variable stars from the Kepler satellite.


Twenty-three new objects have been added to the growing collection of stars observed to have unusual dips in their light curves. A recent study examines these stars and the potential causes of their strange behavior.

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Star Discovered in Closest Known Orbit Around Likely Black Hole

Astronomers have found evidence for a star that whips around a black hole about twice an hour. This may be the tightest orbital dance ever witnessed for a likely black hole and a companion star.

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SN2015bh: the end of a star or an "impostor" supernova?

Astronomers spot an intense explosion of a massive star, which, according to records, experienced frequent eruptions for at least 20 years. The analysis of the outburst does not allow to discern between a real supernova - an explosive event marks the end of a star - or a giant eruption implying a massive change in the star’s evolutionary course

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Iota Orionis: pulsating beacon of a constellation

Using the world's smallest astronomical satellites, researchers detect the biggest stellar heartbeat ever...

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