First Asteroid With Rings Discovered (like how cool is that?!)
Until now it seemed that only giant planets had the gravity to hold on to the billions of bits of orbiting ice and dust that make up a ring, but in a paper published today in Nature, astronomers report the discovery of two icy rings around a small object named Chariklo that orbits between Saturn and Uranus.
The discovery was made possible by observations at many sites in South America, including ESO's La Silla Observatory. The origin of these rings remains a mystery, but they may be the result of a collision that created a disc of debris.
"This probably will be the biggest discovery of my career," says Felipe Braga-Ribas of the National Observatory in Brazil, who led the team that found the rings, and who received his Ph.D. just last year.
From the far, far away to the startlingly close, there have been over 600,000 asteroids identified in the inner solar system since 1980. This visualization tracks them all.
The video is the work of Scott Manley. Manley included the path of the near-by asteroids that have been identified starting 34 years ago and carrying on to this year. The asteroids that cross our own orbit are in red, the ones that just get close are in yellow, and the ones even further out are all in green.
When you think of a celestial ring system, the beautiful ringed planet Saturn will likely jump to mind. But for the first time astronomers have discovered that ring systems aren’t exclusive to planetary bodies — asteroids can have them too. Read more
NASA’s Spitzer Space Telescope has spotted an eruption of dust around a sun-like star, possibly the result of a smashup between large asteroids. This type of collision can eventually lead to the formation of planets. "We are watching rocky planet formation happen right in front of us," said George Rieke, a University of Arizona co-author of the new study. "This is a unique chance to study this process in near real-time."
read more here artist concept credit: NASA/JPL-Caltech
Observations at many sites in South America, including ESO’s La Silla Observatory, have made the surprise discovery that the remote asteroid Chariklo is surrounded by two dense and narrow rings. This is the smallest object by far found to have rings and only the fifth body in the Solar System — after the much larger planets Jupiter, Saturn, Uranus and Neptune — to have this feature. The origin of these rings remains a mystery, but they may be the result of a collision that created a disc of debris. The new results are published online in the journal Nature on 26 March 2014.
Dinosaur-killing asteroid hit at just the wrong time
Animals might have survived if impact happened a few million years earlier or later.
Just before a large asteroid slammed into the Earth 66 million years ago, the diversity of plant-eating dinosaur species declined slightly, a new study suggests. That minor shift may have been enough to doom all dinosaurs when the space rock hit.
The scarcity of plant-eaters would have left them more vulnerable to starvation and population collapse after the impact, with consequences that rippled all the way up the food chain.
“The asteroid hit at a particularly bad time,” says Stephen Brusatte, a palaeontologist at the University of Edinburgh, UK. “If it had hit a few million years earlier or later, dinosaurs probably would have been much better equipped to survive.”
Brusatte and his colleagues describe this nuanced view of the famous extinction in Biological Reviews.
This colorful image from NASA’s Dawn mission shows material northwest of the crater Sextilia on the giant asteroid Vesta. Sextilia, located around 30 degrees south latitude, is at the bottom right of this image.
The image was taken by Dawn’s framing camera from September to October 2011.
In this image, the entire color spectrum of Vesta becomes visible. While a large asteroid impact probably brought the black material, the red material may have been melted by the impact.
The composite image was created by assigning ratios of color information collected from several color filters in visible light and near-infrared light to maximize subtle differences in lithology (the physical characteristics of rock units, such as color, texture and composition). The color scheme pays special attention to the iron-rich mineral pyroxene.