The siriometer is a rarely used astronomical measure equal to one million astronomical units, i.e., one million times the average distance between the Sun and Earth. This distance is equal to about 149,597,870,000,000,000 meters (149.6 Pm) or about 15.813 light-years, which is roughly twice the distance from Earth to the star Sirius.
The proposed symbol for the siriometer is (Sm).
- On the units of distance in stellar astronomy, Malmquist, K. G., The Observatory, Vol. 48, p. 142-144 (1925) 
- "WolframAlpha". Retrieved 25 April 2012.
- https://www.gutenberg.org/files/22157/22157-h/22157-h.htm Lectures on Stellar Statistics. Charlier. 1921
|This astronomy-related article is a stub. You can help Wikipedia by expanding it.|