After this month’s meteor exploded over Russia with the power of several atomic bombs, most Earthlings might prefer space rocks to keep their distance.
Not Alan Hildebrand. The University of Calgary planetary scientist is keen to find space rocks close enough to visit.
“It would be great if there was something half a kilometre in diameter or bigger,” says Hildebrand, who plans to search for near-Earth asteroids with a new Canadian satellite that blasted into orbit Monday.
The $24-million asteroid hunter, called NEOSSat, launched on an Indian rocket. It is also carrying Canada’s first military satellite, called Sapphire, and two tiny “nanosats” that are part of projects by Austria, Poland and Canada to study the brightest stars in the sky.
Monday’s “hat trick” for Canadian space science, as astronomer Jaymie Matthews of the University of British Columbia describes it, showcases both Canada’s leadership in the miniaturization of space telescopes and the country’s growing role as a “traffic reporter” in space.
NEOSSat, which is the size of a suitcase, will circle the globe every 100 minutes scanning for near-earth asteroids. It will also offer “unprecedented opportunities” for tracking man-made space junk, says the Canadian Space Agency.
Sapphire, which cost $65 million, is also “an eye in the sky for space debris,” Defence Minister Peter MacKay said last fall before the satellite was shipped off to India for launch.
Sapphire, a cube that measures a metre across, will orbit with the sun behind it. This will enable it to pick up the light reflecting off old rocket boosters, dead satellite and debris that threaten operating satellites and spacecraft.
“The Sapphire satellite will be integral to increasing our ability to protect Canadian and allies’ assets and interests in space,” MacKay said, adding it is “an essential component to our robust defence for Canada and North America, through NORAD.”
James Fergusson, director of the Centre for Defence and Security Studies at the University of Manitoba, says the strategic significance of Sapphire should not be under-estimated.
He suggested in a recent report that Sapphire will enhance NORAD’s early warning system of ballistic missile attack on North America. The system needs to be able to “differentiate between objects that may be de-orbiting for a variety of reasons and ballistic missile warheads, thereby avoiding potential dangerous assessment errors,” Fergusson wrote in Vanguard, a forum for the security and defence community.
Sapphire and NEOSSat are secondary cargo on India’s Polar Satellite Launch Vehicle carrying an Indo-French Eearth observation satellite.
One of tiny nanosats also riding on the rocket was designed and assembled at the Space Flight Laboratory (SFL) of the University of Toronto Institute for Aerospace Studies (UTIAS). Its twin was also designed in Canada, but assembled in Austria.
They are the smallest space telescopes ever – just 20 centimetres across and less than seven kilograms each – and part of the BRITE Constellation being created by Austria, Poland and Canada to study the brightest stars. The constellation will have six nanosats in orbit when it’s complete in 2014.
“BRITE is expected to demonstrate that nano-satellites are now capable of performance that was once thought impossible for such small spacecraft,” says Cordell Grant, manager of satellite systems at the Toronto Space Flight Laboratory.
He says the diminutive telescopes are part of the new wave of nano-satellites that can be developed quickly, by a small team and at a cost that is within reach of many universities and small companies.
They evolved from technology Grant, Matthews and their colleagues developed for MOST, Canada’s first space telescope launched in 2003, which is the size of a suitcase.
Once the Indian rocket delivers the satellites into orbit, control teams on the ground will take over.
A group at the Canadian Space Agency in Montreal hopes to pick up NEOSSat using an international network of ground stations within a few hours of launch.
“First contact is planned to happen over Antarctica, ” says Guennadi Kroupnik, director of the CSA’s satellite communication and space environment projects.
Once they confirm NEOSSat is in “good health” 800 kilometres above the ground, he says they will begin a two-month commissioning period to make sure the spacecraft performs as planned.
“Fingers crossed,” says Hildebrand in Calgary, who leads the NEOSSat team that will comb through the hundreds of images the satellite generates each day hunting for asteroids not easily spotted with ground-based telescopes.
NEOSSat, which is short for Near-Earth Object Surveillance Satellite, will also be used to track satellites and “space junk” as part of a High Earth Orbit Surveillance System project led by Defence Research and Development Canada, an arm of the defence department. “Unlike ground-based telescopes, NEOSSat will be able to track satellites and space debris in a wide variety of locations and not be limited by geographic location, the day-night cycle, or weather,” says the Canadian Space Agency.
The same holds for asteroids – especially asteroids that spend most of their time between the sun and the Earth and are hard to see from the ground, says Hildebrand.
While the mere mention of asteroids often leads to speculation about space rocks slamming into Earth, Hildebrand says it is important to keep things in perspective.
The meteor that fell over Russia on Feb. 15 was the biggest in a century and injured more than 1,000 people, most of them from flying glass caused by the explosion. Automobiles and traffic accidents, Hildebrand notes, kill more than a million people each year.
There is a possibility NEOSSat may spot asteroids on a collision course with Earth, but Hildebrand says he is more excited about the prospect of finding large asteroids that might be close enough to visit with either a crewed or uncrewed spacecraft.
If they do spot asteroids that pose a threat to Earth, he says it would be important to check out their geology to evaluate different scenarios for diverting them, which range from blowing them up to nudging them away.
He says there is also growing interest in mining nearby asteroids for minerals or water that could be useful for future space missions, or used to revive billion-dollar satellites than now die when they run out of fuel.
“The more we know about the near-Earth (asteroid) population, the more possibilities we open up,” says Hildebrand.