AstroEvent of the Week:29th-September 5th, 2008: Spot Neptune! September 29, 2008
Posted by webmaster in : Astro News & Commentary, Weekly Astro-events , trackbackNow, to spot a planet that was first located mathimatically.
Neptune and Triton as imaged by the Voyager 2 spacecraft in 1989. (Credit: NASA/JPL).
Now that the Moon is out of the sky this week, it’s a good time to add the outer most gas giant to your “been there, done that” list! First spotted in 1846 by Johann Galle & Heinrich D’Arrest, Neptune’s position was first deduced by the French Mathematician Le Verrier, who himself hated the “grittiness” of rank and file observational astronomy. This was considered a triumph of Newtonian physics. Even a small telescope or powerful binoculars will reveal Neptune; a six-inch will begin to reveal a featureless gray-green disk. A decent finder chart can be found at this link… just remember, it’s charted for the southern hemisphere! Neptune is fresh past opposition on August 15th, and lies in the constellation Capricornus. Just think, in the 162 years since its discovery, it has yet to complete one 165 year orbit of the sun! The lucky few with access to apertures of 10″ or larger may want to have a go at spotting Triton, Neptunes’ largest moon at magnitude 13.
This weeks Astro-Word of the Week is Opposition. This term simply refers to when an outer planet is opposite to the sun as viewed from the Earth. The exact moment is measured in position by Right Ascension, or when the planet is exactly 12 hours or 180 degrees separation from the sun, a position Mercury or Venus can never attain!
Comments»
no comments yet - be the first?