2018-03-10 00:20:26 UTC
Spacecraft Could Nuke Dangerous Asteroid to Defend Earth
By Mike Wall, Space.com Senior Writer | March 9, 2018 06:56am ET
'HAMMER' Time? Spacecraft Could Nuke Dangerous Asteroid to Defend Earth
Artist's illustration of an asteroid headed for Earth.
Credit: European Space Agency
The next time a hazardous asteroid lines Earth up in its crosshairs, we
may be ready for the threat.
Scientists and engineers with the U.S. government have drawn up plans
for a spacecraft that could knock big, incoming space rocks off course
via blunt-force impact or blow them to bits with a nuclear warhead,
BuzzFeed News reported.
The researchers announced the concept vehicle, known as the
Hypervelocity Asteroid Mitigation Mission for Emergency Response
(HAMMER), in a study in the February issue of the journal Acta
Astronautica. And the team will discuss HAMMER at an asteroid-research
conference in May, according to BuzzFeed News. [Potentially Dangerous
Each HAMMER spacecraft would weigh about 8.8 tons (8 metric tons). If an
asteroid threat is detected early enough, a fleet of the vehicles could
be dispatched to collide, nuke-free, with the space rock, changing its
trajectory enough to spare Earth from an impact.
But this strategy wouldn't work for big asteroids that appear out of the
cosmic gloom with little warning; there wouldn't be enough time for the
nudge to take effect. To neutralize, or at least mitigate, such threats,
a HAMMER would have to be outfitted with a nuke, the study team stressed.
"Whenever practical, the kinetic impactor is the preferred approach, but
various factors, such as large uncertainties or short available response
time, reduce the kinetic impactor's suitability and, ultimately,
eliminate its sufficiency," the researchers wrote in the Acta
Astronautica paper. The research is part of a broader study by NASA and
the National Nuclear Security Agency to better understand humanity's
options when presented with a potentially threatening near-Earth object
To arrive at these results, and refine HAMMER's design, the team modeled
how to deal with a potential real-life scenario: What if the
1,640-foot-wide (500 meters) near-Earth asteroid Bennu was headed right
for our planet? There's a 1-in-2,700 chance that this will indeed
happen, on Sept. 21, 2135, BuzzFeed News reported.
"Bennu was selected for our case study in part because it is the
best-studied of the known NEOs," the researchers wrote. "It is also the
destination of NASA's OSIRIS-REx sample-return mission, which is, at the
time of this writing, en route to Bennu following a September 2016 launch."
Asteroid Basics: A Space Rock Quiz
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OSIRIS-REx — whose name is short for Origins, Spectral Interpretation,
Resource Identification, Security, Regolith Explorer — is scheduled to
arrive at Bennu this summer. The spacecraft will study the asteroid from
orbit for two years, then swoop in to grab a sample, which will return
to Earth in a special container in September 2023, if all goes according
OSIRIS-REx is an $800 million mission. It's unclear how much a HAMMER
spacecraft would cost, if one ever gets built (which is certainly no
guarantee, given that it's a concept vehicle at this stage). The study
team declined to estimate a price, BuzzFeed News reported.
You can read the full BuzzFeed story here:
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@Spacedotcom, Facebook or Google+. Originally published on Space.com.