Terry's Astronomy Thread.

[Bluearrowll]

What's in the sky tonight?
October 29, 2013

-Look high in the northeast after dark for Cassiopeia standing on end. With the Moon out of the evening sky, now's a fine time to hunt some of Cassiopeia's star clusters and nebulae.

-As October comes to an end, a series of CMEs will sweep past Earth. The first three are expected to deliver glancing blows on Oct. 28th through Oct. 30th, possibly having little effect. A more direct hit is likely on Oct. 31st when a CME from Earth-facing sunspot AR1882 arrives. It was propelled in our direction by an M4-class flare on Oct. 28th. High-latitude sky watchers should be alert for auroras on Halloween.

-he sun is dotted with spots, and three of them pose a threat for strong eruptions. Today's sunspots most-likely-to-flare are circled in this Oct. 29th image of the sun from NASA's Solar Dynamics Observatory. AR1875, AR1882 and AR1875 have 'beta-gamma-delta' magnetic fields that harbor energy for X-class solar flares. One of these spots in particular, AR1882, is almost directly facing Earth, so any eruptions it unleashes would almost surely be geoeffective. NOAA forecasters estimate a 70% chance of M-class flares and a 35% chance of X-flares on Oct. 29th.

News Posted Today:
October 29, 2013
November 3rd's Rare Solar Eclipse


Astro Picture of the Day:
October 29, 2013

Source:
If you climbed this magnificent tree, it looks like you could reach out and touch the North Celestial Pole at the center of all the star trail arcs. The well-composed image was recorded over a period of nearly 2 hours as a series of 30 second long, consecutive exposures on the night of October 5. The exposures were made with a digital camera fixed to a tripod near Almaden de la Plata, province of Seville, in southern Spain, planet Earth. Of course, the graceful star trails reflect the Earth's daily rotation around its axis. By extension, the axis of rotation leads to the center of the concentric arcs in the night sky. Convenient for northern hemisphere night sky photographers and celestial navigators alike, the bright star Polaris is very close to the North Celestial Pole and so makes the short bright trail in the central gap between the leafy branches.