Before it flew past Earth, the asteroid 2014 HQ124 was nicknamed "the Beast" — but now that astronomers have captured pictures of it using a couple of the world's biggest radio dishes, they have a different name for it.
"These radar observations show that the asteroid is a beauty, not a beast," Alessondra Springmann, a data analyst at the Arecibo Observatory, said Thursday in a news release.
The radar images, acquired using Arecibo's 1,000-foot-wide (305-meter-wide) dish in Puerto Rico and the 230-foot (70-meter) Goldstone DSS-14 antenna in California, show that 2014 HQ124 looks something like a bowling pin. This pin is at least 1,200 feet (370 meters) wide and spins on its axis every 20 hours or so.
Arecibo and Goldstone are able to see the detail in radar reflections where most ground-based telescopes would see only a point of light. Recently installed equipment in Puerto Rico made it possible to combine Goldstone's superior 3.75-meter image resolution with Arecibo's greater sensitivity.
Mike Nolan, a staff scientist at the Arecibo Observatory, said that double-team capability makes it possible to characterize the structure of asteroid far more precisely. That level of detail will affect how asteroid-watchers deal with the perils and prospects to come.
"Say you wanted to send a mission to push on an asteroid," Nolan told NBC News. "It would help a lot to know if it was a pile of gravel or solid rock. And if you're going to mine an asteroid, you'd want to know if you should bring a shovel or some dynamite."
It's a bit too early to say exactly what kind of animal the Beast is. But Lance Benner, a scientist at NASA's Jet Propulsion Laboratory who led the radar observations at Goldstone, suggested in a news release that 2014 HQ124 may have been formed from two smaller asteroids that came together as a "contact binary."
The asteroid was discovered on April 23, and was judged big enough to destroy entire cities if it were to hit Earth in the wrong place. That's what led to the "Beast" nickname. Fortunately, the Beast flew past us on Sunday at a completely safe distance of 776,000 miles (1.25 million) kilometers, or slightly more than three times the distance between Earth and the moon.
The radar views were acquired shortly after the closest approach, while 2014 HQ124 was zooming away at a distance of 864,000 to 902,000 miles (1.39 million to 1.45 million kilometers).
Update for 1:50 p.m. ET June 12: I've added in some comments from Nolan, and also had a chance to ask Springmann what she thought the Beast looked like. "I have a little toy penguin on my desk," she said, and the radar images remind her of that penguin — right down to a radar shadow that looks like the bird's beak.
Nolan and Ellen Howell led the observations of HQ124 from Arecibo, along with other staff members and students. In addition to Benner, Marina Brozović, Joseph Jao and Clement Lee of JPL carried out radar observations from Goldstone.