We still can’t protect Earth from potentially hazardous asteroids

Final 12 months, NASA’s DART mission made headlines after it efficiently smashed into the facet of Dimorphos, the small orbiting companion of a bigger asteroid named Didymos. That deliberate impression measurable modified the orbit of Dimorphos, heralding a brand new chapter in humanity’s skill to defend itself from cosmic threats.

One small downside: We have now little or no concept of what these threats are and the place they could come from. Fortunately, NASA is hoping to vary that.

What number of near-Earth asteroids are there?

To place it mildly, rogue asteroids pose a significant menace to our survival right here on Earth. The most important asteroids — these bigger than 0.6 miles (1 kilometer) throughout — are able to triggering extinction-level occasions on Earth. Nevertheless, giant asteroids are comparatively uncommon, putting Earth solely each half-million years or so.

What’s extra regarding are the smaller, far more quite a few asteroids which can be lower than 0.6 miles (1 km) throughout. Whereas these received’t destroy a civilization, they may nonetheless take out a significant metropolis or two, or set off globe-spanning tsunami waves.

In 2005, the U.S. Congress determined that NASA ought to up its asteroid-detection sport. Congress mandated that NASA establish, monitor, and characterize 90 % of near-Earth objects (NEOs) with a diameter better than 560 toes (140 meters). That’s so giant that actually catastrophic issues would occur ought to such an asteroid strike Earth.

There was a deadline for the mandate, too: NASA was directed to perform the NEO-detection effort by 2020.

One catch, nonetheless. Regardless of the clear directive, Congress didn’t authorize any extra funding for NASA to truly accomplish it.

NASA pushes for planetary protection

Because the 2020 deadline loomed, the intelligent of us at NASA acquired inventive. As a substitute of relying solely on ground-based surveys, which have been sluggish and troublesome to fund, they prioritized new spaceflight missions, serving to them promote the idea of planetary protection to Congress.

It labored. Congress accredited the funding for DART a 12 months earlier than NASA even formally proposed it.

Together with DART additionally got here a repurposing of the defunct WISE spacecraft, which had been sitting dormant in orbit for a number of years. Now referred to as NEOWISE (for near-Earth Object Large-field Infrared Survey Explorer), the rebranded instrument is now NASA’s go-to facility for locating potential threats to Earth.