The biggest star in the sky

This is an IR Observation of R Doradus, a variable star in the constellation of Dorado (the Swordfish), located in the far southern sky. R Doradus is a variable star with a period of about 338 days, changing its magnitude from approximately 4.8 at maximum (when it is visible with the unaided eye) to 6.6 at minimum (when it requires a small telescope). R Doradus is approximately 200 light-years away.

The measured size implies that it has a physical diameter of 370 +- 50 times that of the Sun, or well over 250 million km! If R Doradus would be placed at the centre of the Solar System, its surface would be outside of the orbit of Mars. Although even bigger stars are known — Betelgeuse for one — none appears as large in the sky because they are all at greater distances. The very large apparent size of R Doradus is due to the combination of its relative proximity and large physical size.

Forrás:

ESO

About the Image

Id:eso9706a
Típus:Observation
Közzététel napja:1997. március 11.
Related releases:eso9706
Size:1151 x 605 px

About the Object

Név:Gamma Reticulli, R Doradus
Típus:Milky Way : Star : Evolutionary Stage : Red Giant
Milky Way : Star : Type : Variable
Category:Stars

Képformátumok

Large JPEG
127,7 KB
Screensize JPEG
90,1 KB

Háttérképek

1024x768
147,9 KB
1280x1024
203,3 KB
1600x1200
265,1 KB
1920x1200
296,6 KB
2048x1536
367,5 KB

Colours & filters

BandWavelengthTelescope
Infrared
Near-IR
1.25 μmNew Technology Telescope