Recently in the Comets Category

Scientists eagerly await the arrival of a recently discovered, highly active comet that will skim 730,000 miles above the Sun's surface on Nov. 28 and has the potential to be readily visible from Earth.

From NASA ScienceCast: "A comet is heading for Mars, and there is a chance that it might hit the Red Planet in October 2014. An impact wouldn't necessarily mean the end of NASA's Mars program. But it would transform the program along with Mars itself."

The latest trajectory of comet 2013 A1 (Siding Spring) generated by the Near-Earth Object Program Office at NASA's Jet Propulsion Laboratory in Pasadena, Calif., indicates the comet will pass within 186,000 miles (300,000 kilometers) of Mars and there is a strong possibility that it might pass much closer.

Comets trailing wispy tails across the night sky are a beautiful byproduct of our solar system's formation, icy leftovers from 4.6 billion years ago when the planets coalesced from rocky rubble.

Every six seconds, for millions of years, comets have been colliding with one another near a star in the constellation Cetus called 49 CETI, which is visible to the naked eye.

The Hergenrother comet is currently traversing the inner-solar system. Amateur and professional astronomers alike have been following the icy-dirt ball over the past several weeks as it has been generating a series of impressive outbursts of cometary-dust material. Now comes word that the comet's nucleus has taken the next step in its relationship with Mother Nature.

A team at Southern Illinois University Edwardsville has developed a new website, IceHunters (http://www.icehunters.org), to challenge the public to discover Kuiper Belt objects in the outer solar system. It is hoped that among the myriad of new objects found by IceHunters there will be an object (or maybe even objects) with just the right orbit to carry it on to a rendezvous with NASA's New Horizons spacecraft.

Amateur astronomers, including Nick James of Chelmsford, Essex, England, have captured video of the interesting object. James generated his video of GP59 on the night of Monday, April 11. The video, captured with an 11-inch Schmidt-Cassegrain telescope, is a compilation of 137 individual frames, each requiring 30 seconds of exposure. At the time, the asteroid was approximately 3,356,000 kilometers (2,081,000 miles) distant. Since then, the space rock has become something of a darling of the amateur astronomy community, with many videos available. Here is one recent posting: http://www.youtube.com/watch?v=O7wsAZNr56E

We performed an image search on Yahoo for "Comet Holmes" on 2010 April 1. Thousands of images were returned. We astrometrically calibrated---and therefore vetted---the images using the Astrometry.net system. The calibrated image pointings form a set of data points to which we can fit a test-particle orbit in the Solar System, marginalizing out image dates and catching outliers. The approach is Bayesian and the model is, in essence, a model of how comet astrophotographers point their instruments.

Only days before the NASA Stardust spacecraft beamed home comet photos long awaited by astronomers, other researchers revealed the factors that motivated citizens to volunteer without pay to examine more than a million images of space dust captured by the spacecraft's predecessor.

The team of researchers headed by Polytechnic Institute of New York University (NYU-Poly) Assistant Professor of Technology Management Oded Nov reported citizen astronomers were best motivated to spend unpaid hours looking for microscopic stardust particles by the project's objectives, the fun they experienced and the reaction they expected from their friends and family. Some of those motivations varied significantly from other crowd-sourced projects.

The iConference 2011, held February 8 - 11, 2011 in Seattle, chose "Dusting for Science: Motivation and Participation of Digital Citizen Science Volunteers" for its Best Paper Award. Co-authors are Nov, Ofer Arazy of the University of Alberta School of Business and David Anderson of Space Sciences Laboratory, University of California, Berkeley (UC Berkeley). A few days after the conference closed, on February 14, the second Stardust spacecraft beamed home its comet images. Meanwhile, thousands of volunteers have been sifting for years through 1.6 million series of digital images in search of interstellar dust captured by the predecessor Stardust spacecraft. That daunting volunteer project, called Stardust@home and headed by UC Berkeley's Space Sciences Laboratory Associate Director Andrew Westphal, was studied by Nov and his colleagues.