An image of the asteroid Gaspra.
Click on image for full size
It's Asteroid Time!
News story originally written on March 17, 1998
There seems to be a lot going on OUT THERE involving asteroids! Let's take a look!
For the last three years, NASA astronomers Robin Evans and Karl Stapelfeldt have hunted through nearly 28,000 Hubble images...their find -- about 100 small asteroids. These asteroids are essentially rocks (1-3 kilometers in size) that orbit between Mars and Jupiter in an area called the main asteroid belt.
"The archive images are distributed fairly evenly across the sky, so we find asteroids according to both their position in the sky and their number," Evans said. "As expected, we see the asteroids concentrated towards the ecliptic plane and we see small asteroids because they are the most numerous. Small main-belt asteroids such as these are the ones most likely to evolve into Earth-crossing asteroids due to encounters with their larger neighbors. Some of the asteroids in our survey could eventually migrate toward Earth."
It is this concern of asteroids coming too near the Earth that is the basis of our next news item! An asteroid discovered just last December (named 1997 XF11) is predicted to have a close encounter with the Earth in just 30 years. In October 2028, this mile-wide asteroid will pass within 600 thousand miles of the Earth. This is considered so close that it has been added to the 'potentially hazardous asteroids' list or PHA's. These PHA's come dangerously close to the Earth and so are monitored very closely. At this time, no PHA is in danger of impacting the Earth.
Shop Windows to the Universe Science Store!
Learn about Earth and space science, and have fun while doing it! The games
section of our online store
includes a climate change card game
and the Traveling Nitrogen game
You might also be interested in:
It was another exciting and frustrating year for the space science program. It seemed that every step forward led to one backwards. Either way, NASA led the way to a great century of discovery. Unfortunately,...more
The Space Shuttle Discovery lifted off from Kennedy Space Center at 2:19 p.m. EST, October 29th. The sky was clear and the weather was great as Discovery took 8 1/2 minutes to reach orbit for the Unitied...more
A moon was discovered orbiting the asteroid, Eugenia. This is only the second time in history that a satellite has been seen circling an asteroid. A special mirror allowed scientists to find the moon...more
Will Russia ever put the service module for the International Space Station in space? NASA officials are demanding an answer from the Russian government. The necessary service module is currently waiting...more
During a period of about two days in early May, 1998, the ACE spacecraft was immersed in plasma associated with a coronal mass ejection (CME). The SWICS instrument on ACE, which determines unambiguously...more
J.S. Maini of the Canadian Forest Service has referred to forests as the "heart and lungs of the world." Forests reduce soil erosion, maintain water quality, contribute to atmospheric humidity and cloud...more
In late April through mid-May 2002, all five naked-eye planets are visible simultaneously in the night sky! This is includes Mercury which is generally very hard to see because of its proximity to the...more