Spinning Sedna

The minor planet Sedna (2003 VB12) was discovered in 2003 and caused a tiny bit of controversy over the way it was named before being numbered. At less than 1800 km in diameter, it isn't quite large enough to be a planet and its orbit is highly elliptical; it gets as close as 80 AU from the Sun and as far as around 800 AU. It takes about 10,500 years to complete an orbit.

A group from the Harvard-Smithsonian Center for Astrophysics have recently observed Sedna with the Multiple Mirror Telescope (MMT) based on Mt. Hopkins, Arizona. Between October 2004 and January 2005, they managed to observe Sedna on eight nights, taking 143 measurements of its brightness. They measured an apparent magnitude of 21 - beyond most amateur telescopes - and saw that it had a variability of about 1%. Their best fit to the data gives a rotation period of 10.27 hours which isn't too different from other bodies in the solar system.

Posted in astro blog by Stuart on Saturday 02nd Apr 2005 (22:43 UTC) | Permalink
[an error occurred while processing this directive]
[an error occurred while processing this directive]