Is it a giant asteroid? Is it a dwarf planet? Is there a difference?
1 Ceres has been classified as both. Ceres is the largest object in the Asteroid Belt between Mars and Jupiter – something like 900 km across. We will get our first really good look at it in about 2 years when NASA’s Dawn spacecraft arrives in its orbit. It was in fact the first “asteroid” discovered, in 1801. It ranges from magnitude 7 to 9, so is almost never visible to the unaided eye, but it’s also pretty easy to find with most telescopes.
I thought I’d take a look using the University of Iowa’s Rigel telescope in Arizona, using the web-based Sierra Stars Observatory Network. Here’s a shot of 1 Ceres captured during the night of 1 May 2013. Ceres is the bright “star” in the middle of the frame. It’s so bright (around magnitude 8) that it’s actually quite overexposed on this cropped image. The image here was made by stacking three 150 second exposures.
The particulars from the FITS file of the first of three images taken by Rigel: DATE-OBS= '2013-05-01T03:25:00.311' / UTC, start of exposure LST = '10:39:31' / Local sidereal time at exposure start POSANGLE= ' 70:48:39' / Position angle, degrees, +W LATITUDE= ' 31:39:56' / Site Latitude, degrees +N LONGITUD= '-110:36:05' / Site Longitude, degrees +E ELEVATIO= ' 38:22:26' / Degrees above horizon AZIMUTH = '283:31:10' / Degrees E of N OBJRA = ' 6:39:18.3' / Target center J2000 RA OBJDEC = ' 28:48:59.6' / Target center J2000 Dec
Copyright © 2013 David Allan Galbraith