Image of the Day:
Comet ISON as photographed from the Teide observatory in the Canary Islands on Nov. 22, 2013. (Source: J.C. Casado/iac.es) If you haven't been able to get up before dawn to witness Comet Ison as it makes its final approach toward the sun, I'm thinking this beautiful photograph may be the next best thing. It was shot from the Teide Observatory in the Canary Islands on Friday, right before sunrise. You're looking down on the cloud deck, and the comet, with its long, glowing tail, is toward the top-center of the picture. (Mercury is the larger glowing spot partially obscured by clouds.) And if that's not enough, check out this timelapse taken on the same morning: http://www.youtube.com/watch?v=xtEb376ARsI&feature=youtu.be Still not enough? You can find more pictures here. As I'm writing this at 2 p.m. MST on Sunday, Nov. 24, the comet is 28 million miles from the sun, and traveling at 172,000 miles per hour, according to Karl Battams of the Comet Ison Observing Campaign. While it has been visible to the naked eye at dawn in the eastern sky, as the photo from the top of this post shows, by Monday the glare from the sun will likely overpower Comet Ison's glow (if it hasn't happened earlier). But a flotilla of spacecraft will have an increasingly great view as the comet approaches the sun. NASA'S STEREO-A spacecraft got a first glimpse of Ison last Thursday. Since then, it has moved further into the spacecraft's field of view. Check it out:
Comet Ison, along with another named Encke, are seen moving in the direction of the sun in this animation of images from the STEREO-A spacecraft. Ison appears larger and moves into the frame at lower left. (Source: Karl Battams/NRL/NASA-CIOC) On Wednesday, the comet will next pass into the field of view of the Solar and Heliospheric Observatory, or SOHO. Assuming that it doesn't disintegrate under the punishing influence of the sun, Ison should become visible to the Solar Dynamics Observatory shortly after 12 noon EST on Thursday. SDO will then track the comet through perihelion, or closest approach to the sun, at a little after 1 p.m., and then watch as it departs, heading out on a trajectory that will likely take it into interstellar space. But will it still be in one piece at that point? There's some evidence suggesting the odds aren't that great. We'll just have to keep watching to find out. I'll be doing just that between now and Thanksgiving — and posting compelling images of Comet Ison as they roll in from the fleet of spacecraft. Lastly, a fair question: Why all the brouhaha over a comet? I'll try to tackle that in a future post.