An explosion and a crater reported near the capital of Nicaragua raised suspicions on Monday that a meteorite had split off from an asteroid that passed by Earth this weekend and struck our planet. But NASA scientists have now cast doubt on whether the blast outside Managua was even a meteorite at all.

The blast left a hole 40 feet (12 meters) wide and 19 feet (5 meters) deep outside the international airport serving Nicaragua's capital. Some Nicaraguan astronomers quoted in early news reports attributed the blast to a chip off a weekend asteroid flyby.

But outside meteorite experts later downplayed links to the small asteroid, dubbed 2014 RC, which passed harmlessly by Earth over the weekend. About the size of a house, 2014 RC passed within 22,000 miles (36,000 kilometers) of our planet on Sunday.

"Information is limited, but the miss distance of 2014 RC actually precludes any related meteorite impact" at the Managua crater, says MIT asteroid expert Richard Binzel, by email.

Managua Meteorite?

Managua residents reported the blast just after midnight. In some news reports, geophysicist Wilfried Strauch of Nicaragua's Institute of Earth Studies attributed the crater to a meteorite impact.

However, NASA asteroid expert Don Yeomans, author of Near-Earth Objects: Finding Them Before They Find Us, says that outside experts suspect the crater wasn't caused by an impact.

"This event was separated by 13 hours from the close Earth approach of 2014 RC, so the explosion and the asteroid are unrelated," says Yeomans, because the Earth moves about 870,000 miles (1.4 million kilometers) in 13 hours. "There was no obvious optical fireball or debris trail seen prior to the explosion, so it seems unlikely that the explosion in Nicaragua was related to a meteorite impact."

Russian Roulette

Meteorite impacts have occurred at the same time unconnected asteroid flybys in the past, most notably in the February 15, 2013, Chelyabinsk impact, which damaged buildings across central Russia. (See "Chelyabinsk Meteor: The Animated Movie.")

That meteorite impact sprang from an object roughly the size of 2014 RC exploding in the atmosphere above Russia, with about 500 kilotons of energy, bright enough to sunburn some watchers. A larger asteroid had passed harmlessly over the Southern Hemisphere on the same date.

Update: In a late Monday report on RC 2014, astronomers at NASA's Near-Earth Object Program based at the Jet Propulsion Laboratory in Pasadena, California, revised size estimates for the asteroid. Radar observations indicate that the asteroid is about 40 feet (12 meters) across and rotates rapidly, several times a minute. That makes it roughly half the size of the 2013 Russian meteorite.

The NASA update also called the meteorite report from Managua "unrelated" to RC 2014, citing the 13-hour difference in the asteroid flyby and the crater explosion. "As yet, no eyewitness accounts or imagery have come to light of the fireball flash or debris trail that is typically associated with a meteor of the size required to produce such a crater," noted the statement.