image 24-August-2019 23:51:17

Artist's impression of the sizes of Sirius B and the Earth

Date: 13 December 2005
Satellite: Hubble Space Telescope
Depicts: Sirius B
Copyright: ESA and NASA

Based on the Hubble measurements made with the Space Telescope Imaging Spectrograph, an international team found that Sirius B has a mass that is 98 percent that of our own Sun. Despite this large mass Sirius B is only 12 000 kilometres in diameter, making it smaller than even the Earth and much denser. Sirius B's powerful gravitational field is 350 000 times greater than Earth's, meaning that a 68 kilogram person would weigh 25 million kilograms standing on its surface.

Last Update: 16 May 2019

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