NASA is committed to grab an asteroid and put it into lunar orbit in the next decade, using a robotic system to put a 40-foot (12-meter) rock into a space shopping bag, and then tow it to the Moon. This apparently useless mission is actually crucial to the survival of humankind.
The space agency calls it the Asteroid Redirect Mission. The image above shows how NASA envisions one of the missions after capture: It will send astronauts to the asteroid in an Orion spacecraft to take samples and return them to Earth. The rings on the bag are hooks for the astronauts to move safely across the asteroid's surface.
NASA has two ideas in mind to capture the asteroid. The first is to "retrieve a large, boulder-like mass from a larger asteroid and return it" to lunar orbit. Imagine it: Send robotic ship to rendezvous with an asteroid, have it remove a chunk that is about 40 feet in diameter, put it inside a bag, and tow it to the Moon. It seems awfully hard and dangerous.
The easier alternative is to "capture and redirect an entire very small asteroid." There's only one problem with this, according to Paul Chodas, a senior scientist at JPL's Near-Earth Object Program Office:
There are hundreds of millions of objects out there in this size range, but they are small and don't reflect a lot of sunlight, so they can be hard to spot. The best time to discover them is when they are brightest, when they are close to Earth.
NASA is already working to identify targets for ARM. The international community has small teams of astronomers dedicated to spot these small objects in the sky using optical telescopes. They send their findings to a computer at the Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, California.
This computer calculates their orbit and size, adding them to a database. Another automated system constantly scans this database for potential candidates, sending an email with the subject line "New ARM Candidate" every time it finds one. According to Chodas this "has happened several dozen times since we implemented the system in March of 2013."
With that data in hand, Chodas contacts NASA's Deep Space Network station at Goldstone, California, the Arecibo Observatory in Puerto Rico, and the Infrared Telescope Facility in Mauna Kea, Hawaii. Combining these stations, scientists can obtain precise "size and rotation information, and at times, even generating detailed images of an asteroid's surface" as well as "wealth of detailed data on spectral type, reflectivity and expected composition." This is when the scientists made their final assessment and put the asteroid in the target list.
The list is way too short so far. With the current budget, NASA can only get about two ARM targets per year.
Why this is important for all of us
According to NASA, the agency has a tiny "$20 million per year in the search for potentially hazardous asteroids through the Near Earth Object Observation Program." They added $105 million to ARM in 2014 and it is actively working with other companies and organizations to accelerate the program as much as possible.
It's a pathetic budget, giving how important this is to the long term survival of humankind. It may sound dramatic, but the NEO and ARM programs are working both to protect us and to provide a path of expansion out of our resource-limited planet. The only path available, in fact.