Showing posts with label Marshall Space Flight Center. Show all posts
Showing posts with label Marshall Space Flight Center. Show all posts

10:05:00 PM

Elusive Constellation Appears With Oct. Meteors

Camel Leopards and Comets Posted on Oct 08, 2010 02:43:20 PM | William Cooke

Camelopardalis.
It's a strange-sounding name for a constellation, coming from the Greco-Roman word for giraffe, or "camel leopard". The October Camelopardalids are a collection of faint stars that have no mythology associated with them -- in fact, they didn't begin to appear on star charts until the 17th century.
Even experienced amateur astronomers are hard-pressed to find the constellation in the night sky. But in early October, it comes to prominence in the minds of meteor scientists as they wrestle with the mystery of this shower of meteors, which appears to radiate from the giraffe's innards.
The October Camelopardalids are not terribly spectacular, with only a handful of bright meteors seen on the night of Oct. 5. It may have been first noticed back in 1902, but definite confirmation had to wait until Oct. 2005, when meteor cameras videotaped 12 meteors belonging to the shower. Moving at a speed of 105,000 miles per hour, Camelopardalids ablate, or burn up, somewhere around 61 miles altitude, according to observations from the NASA allsky meteor cameras on the night of Oct. 5, 2010.
So they aren't spectacular. Their speed is calculated. Their "burn up" altitudes and orbits are known. So what's the mystery?
Camelopardalids have orbits, which indicates that they come from a long period comet, like Halley's Comet. But the Camelopardalids don't come from Halley, nor from any of the other comets that have been discovered. Hence the mystery: somewhere out there is -- or was -- a comet that passes close to Earth which has eluded detection. These tiny, millimeter size bits of ice leaving pale streaks of light in the heavens are our only clues about a comet of a mile, maybe more, in diameter.
This is why astronomers keep looking at the Camelopardalids meteors. They hope that measuring more orbits may eventually help determine the orbit of the comet, enabling us to finally locate and track this shadowy visitor to Earth's neighborhood.
You can see the brief burst of a Camelopardalids meteor in this video. 

2:50:00 AM

Comet To Brighten in October

Comet Hartley 2 Seen in Cassiopeia
Posted on Oct 06, 2010 11:49:04 AM | William Cooke | 
In the image below, taken on the evening of  Friday, Oct. 1, Comet Hartley 2 can be seen in the constellation Cassiopeia (north-east sky, not far from horizon)...more 


2:39:00 AM

Early October SE U.S. Fireball

Fireball in the Sky!
Posted on Oct 04, 2010 04:34:27 PM | William Cooke 
It was brief, but it was brilliant! On Saturday, Oct. 2, 2010 at approximately 8:50 p.m. CDT, cameras operated by NASA's Meteoroid Environment Office at Marshall Space Flight Center in Huntsville, Ala., recorded a slow moving fireball moving from the north to the southwest...more