NASA may have an explanation for mysterious ‘boom-like’ sounds heard in Virginia
NASA may know something about the mysterious booms heard around northern Virginia late last week.
Dispatch centers in the area got a a flood of 911 calls around 10:30 a.m. Friday from people saying they heard a loud explosion or “sonic boom,” NBC Washington reports. But authorities found no evidence of any explosion, and the U.S. Geological Survey didn’t register an earthquake in the area.
Instead, the booms could be explained by a meteoroid.
NASA Meteor Watch said a “probable” fireball — which is an “exceptionally bright” meteor — was detected over northern Virginia and eastern West Virginia around 10:30 a.m. Friday. Around that time, the agency got numerous reports of “boom-like sounds” associated with a couple of fireball sightings in the area.
“It made a loud explosive sound that shook my house in Rileyville, VA,” one user commented on Facebook.
“We thought something big had fallen on our roof and bounced and fallen again here in Strasburg,” another wrote.
There isn’t much information on the possible fireball, NASA said. But a “strong fireball-like signature” did show up in data from the GOES 16 Geostationary Lightning Mapper, which NASA said detects “all forms of lightning.”
That data allowed NASA to estimate the “energy of this event.”
By comparing it to a previous fireball, NASA estimated the brightness of Friday’s meteor to be around the same as a full moon — corresponding to an energy equal to about 1 or 2 tons of TNT and a “mass of around 50 pounds for the object causing the fireball.”
The fragmentation of the object also produced pressure waves that got picked up by seismometers and infrasound instruments in the area, according to NASA.
NASA said an quick analysis of those signals “indicated an energy of a few tons of TNT,” which is in “reasonable agreement” with the amount of energy it estimated based on the Geostationary Lightning Mapper data.
“No camera imagery has surfaced so far, due to the heavy cloud cover over the region,” NASA said. “It is possible that this event produced meteorites somewhere in the northern Virginia/eastern West Virginia area.”
NASA said its estimations are “pretty uncertain” because of a lack of data and that it will give an update when it knows more about the possible fireball.
Meteoroids are asteroid or comet fragments that orbit the sun while meteors — also called shooting stars — are the “visible paths of meteoroids that have entered the Earth’s atmosphere at high velocities,” according to NASA.
Fireballs are sometimes seen by people at night but are much more rarely seen during the day, NASA said. The objects that cause them can exceed a meter in size but are usually not big enough to stay in one piece when falling through Earth’s atmosphere.
This story was originally published September 19, 2021 at 1:09 PM with the headline "NASA may have an explanation for mysterious ‘boom-like’ sounds heard in Virginia."
