New research from NASA's Spitzer Space Telescope reveals that asteroids somewhat near Earth, termed near-Earth objects, are a mixed bunch, with a surprisingly wide array of compositions. Like a piņata filled with everything from chocolates to fruity candies, these asteroids come in assorted colours and compositions. Some are dark and dull; others are shiny and bright. The Spitzer observations of 100 known near-Earth asteroids demonstrate that the objects diversity is greater than previously thought. The findings are helping astronomers better understand near-Earth objects as a whole -- a population whose physical properties are not well known. Read more
A video showing how many asteroids are circulating the Earth has been created by British astronomer Scott Manley. It shows the locations of all the asteroids discovered by telescopes since 1980 through to the present day. Read more
Title: On Near-Earth Asteroid Study at Department of Astronomy, Bandung Institute of Technology Authors: S.Siregar
Since1984 asteroid study is conducted at Department of Astronomy, Bandung Institute of Technology. At present there are two main streams in our research, dynamical and physical study. Astronomers determine the orbital elements of more than 12000 asteroids, and the number is increasing. In the distribution of orbital elements of asteroids, there are several features such as Kirkwood gap, groups, and families. To know the dynamical evolution of asteroids, it is very important to study these features. Recently some small bodies of our solar system have been approached to the Earth, one of them was Toutatis. These objects are interested to study. Based on 2384 asteroids taken from NASA.File the phenomenon of orbital elements a, e, i, {\Omega}, {\omega} and Tisserand invariant, T of Near-Earth asteroids are briefly described.
One of NASA's newest space telescopes has spotted 25,000 never-before-seen asteroids in just six months. Ninety-five of those are considered "near Earth," but in the language of astronomy that means within 30 million miles. Luckily for us, none poses any threat to Earth anytime soon. Read more
Title: ExploreNEOs I: Description and first results from the Warm Spitzer NEO Survey Authors: D. E. Trilling, M. Mueller, J. L. Hora, A. W. Harris, B. Bhattacharya, W. F. Bottke, S. Chesley, M. Delbo, J. P. Emery, G. Fazio, A. Mainzer, B. Penprase, H. A. Smith, T. B. Spahr, J. A. Stansberry, C. A. Thomas
We have begun the ExploreNEOs project in which we observe some 700 Near Earth Objects (NEOs) at 3.6 and 4.5 microns with the Spitzer Space Telescope in its Warm Spitzer mode. From these measurements and catalogue optical photometry we derive albedos and diameters of the observed targets. The overall goal of our ExploreNEOs program is to study the history of near-Earth space by deriving the physical properties of a large number of NEOs. In this paper we describe both the scientific and technical construction of our ExploreNEOs program. We present our observational, photometric, and thermal modelling techniques. We present results from the first 101 targets observed in this program. We find that the distribution of albedos in this first sample is quite broad, probably indicating a wide range of compositions within the NEO population. Many objects smaller than one kilometre have high albedos (>0.35), but few objects larger than one kilometre have high albedos. This result is consistent with the idea that these larger objects are collisionally older, and therefore possess surfaces that are more space weathered and therefore darker, or are not subject to other surface rejuvenating events as frequently as smaller NEOs.
Astronomers have long worried that a large space rock would remain undetected until it was about to smash into Earth, in what might be called the "Armageddon" scenario. In that 1998 blockbuster starring Bruce Willis, the rock in question is described as "the size of Texas." The truth is that even a boulder measuring 200 feet across -- as wide as a soccer field -- could kill thousands. Now, however, the odds of an apocalypse-by-asteroid are shrinking. Read more
New Hawaii Telescope Searches for Killer Asteroids
Scientists in Hawaii are using what is believed to be the world's largest digital camera to search for killer asteroids. Pan-STARRS, or Panoramic Survey Telescope & Rapid Response System, contains a 1,400 megapixel digital camera that searches for objects that move or change brightness from one night to the next. Read more
Asteroid astronomers awarded unprecedented amount of telescope time
UK planetary science will be among those to benefit from an exceptional award of 82 nights of European Southern Observatory (ESO) telescope time made to an international team of astronomers. The team will study how near-Earth asteroids (NEAs) react to a phenomenon known as the YORP effect. Read more
While our planet rarely collides with planetoids or comets larger than a couple of hundred metres in diameter, they have a tremendous appeal on the imagination, comparable perhaps to the shark, another age-old Hollywood darling. According to their report, only 3 to 6 swimmers die in shark attacks annually, while smoking costs five million lives annually, but does not do so well at the box office. Traffic worldwide takes 1.2 million lives every year. Meteorites' death toll clocks in at 91 people a year, according to the report. On average that is. An average reconstituted over millions of theoretical years. Commonly, a single strike might claim countless lives, while most years will remain without incident. Read more