Asteroid 2010 XC15 is estimated to have a diameter of about five hundred meters and orbits the Earth about twice as long as the Moon. The results of the experiment could help defend the Earth from larger asteroids that could cause significant damage.
“We will analyze the data over the next few weeks and hope to publish the results in the coming months,” said Mark Haynes, who leads the project. “This experiment was the first attempt to observe asteroids at such low frequencies. It shows the importance of the HAARP facility as a potential future research tool for studying near-Earth objects,” he said.
HAARP and the asteroids
The device known by the acronym HAARP (High Frequency Active Auroral Research Program) is a system of special antennas that have been carrying out research on the ionosphere in Alaska since the 1990s.
After the project was completed under US Air Force sponsorship, the University of Alaska at Fairbanks assumed control of the building, which it still operates today. HAARP has a number of very useful properties.
Several programs exist to rapidly detect asteroids, determine their orbits and shapes, and visualize their surfaces, using optical telescopes or the Deep Space Network planetary radar, NASA’s network of large and highly sensitive radio antennas in California, Spain and Australia.
However, these radar programs do not provide information about the planet’s interior. They use short wavelength signals that bounce off the surface and provide high quality external images, but do not penetrate the object. However, long wavelength radio signals can reveal the insides of objects.
A threat from space
Data analysis should take several weeks. Tuesday’s experiment also served as a test to explore a larger asteroid that would be larger than Tuesday’s. Asteroid Apophis, discovered in 2004, will make its closest approach to Earth on April 13, 2029. It will get closer to Earth than many geostationary satellites orbiting the planet.
Apophis, estimated by NASA to be about 1,100 meters in diameter, was originally predicted to pose a risk to Earth in 2068, but scientists have since better estimated its orbit and it is now out of danger to the planet for at least a century. However, scientists want to know more: the more time humanity has had to prepare, the better it could react to a potential collision threat.
Tuesday’s test followed tests in January and October, in which scientists bounced signals off the moon in preparation for the experiment.
Haynes said that understanding the composition of an asteroid’s interior, especially an asteroid large enough to cause major damage to Earth, can increase the chances of an effective defense. Knowing the distribution of matter within a dangerous asteroid could help scientists pinpoint devices designed to deflect the asteroid away from Earth.