Unexplained brightening of AKO 9 in 47 Tucanae

This is a reproduction of two images obtained in late 1996 with the Hubble Space Telescope (HST) , showing the field of the variable star AKO 9 at the centre of the southern globular cluster 47 Tucanae .

This star brightened by more than 2 magnitudes (a factor of seven) in less than 1 hour. Left: the first frame; right: the last frame in a series of 15 exposures, obtained during a period of just over 4 hours.

Yhe field of each image measures 3.9 arcsec x 3.9 arcsec. North is up and East is to the left.
No other star among the > 30,000 studied was found to have such a large amplitude.



About the Image

Release date:15 January 1997
Related releases:eso9703
Size:3284 x 1629 px

About the Object

Name:47 Tucanae, AKO 9
Type:Milky Way : Star : Type : Variable
Milky Way : Star : Grouping : Cluster : Globular
Distance:15000 light years
Category:Star Clusters

Image Formats

Large JPEG
1.5 MB
Screensize JPEG
235.1 KB

Colours & filters

300 nmHubble Space Telescope

Exposure time: 4350s


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