The US’s mid-Atlantic region was thunderstruck Thursday afternoon by an explosion. According to the United States Geological Survey the first event happened at 1:24 p.m. Eastern Standard Time about 2 miles / 3 kilometers north-northeast of Hammonton, NJ, possibly over Wharton State Forest. Over the next ninety minutes, nine more sonic booms were reported from southern New Jersey to as far north as Connecticut [1][2][3]. William Yeck at the USGS told Philly.com‘s Sam Wood, “We haven’t seen anything to suggest there has been an earthquake. We have been getting a lot of calls and see signals consistent with a sonic boom.” [4]
Sonic booms are formed by shock waves when an object travels faster than the speed of sound through an atmosphere. As an object goes faster, shock waves are compressed into a single shock wave exploding ahead of an object when it achieves Mach 1. That speed is equivalent to 761 mph/1,225 kph, which is pretty damned quick.
With temperatures hovering at the 40°F/4°C mark all day, the local weather was perfect for everyone in the region to hear the explosion. Cold air slows down sound but doesn’t diminish its intensity, potentially allowing distant locations to experience booms with minimal change in volume. Last Saturday New Jersey, New York, and Connecticut were buried under two feet / sixty centimeters of snow with plenty still on the ground. Snow doesn’t reflect sound, that’s why snowy scenes are always so hushed in movies and real life. This may contribute to the perception of sound directed at a listener.
Now for the $64,000 question: “Who was it?”
Thirty seven miles north-northeast of Hammonton is Joint Base McGuire-Dix-Lakehurst, New Jersey’s Air Force base and a clear suspect.
Or they were…
Further south is the 177th Fighter Wing of the Air National Guard outside of Atlantic City, home to several F-16 jets capable of 1.6 Mach. Andy Polhamus of NJ.com notes, “Two readers have written in to say they saw military aircraft maneuvering over the water near Atlantic City.” [5] In addition to this, the Twitter account @AtlanticCity911 shared an intriguing audio clip of an Atlantic City police dispatcher:
But the 177th’s Jersey Devils deny responsibility.
Taking the USGS and the 177th at their word, there’s the problem of Hammonton being 30 miles / 48 km northwest of the Atlantic ocean. If the source of the sonic boom took off from McGuire AFB at Hammonton’s northeast, it would’ve been travelling towards the southwest. Sonic booms follow the path taken by supersonic objects, one wonders why these were heard, and felt, to the northeast in Long Island and Connecticut.
Compounding the confusion is Maryland’s Naval Air Station Patuxent River announcing they were behind it. A naval spokesperson reached out to the Associated Press, saying a test flight of the Lockheed Martin F-35C Lightning stealth fighter off the east coast on Thursday afternoon.[6] This corroborates the previous two readers reporting military jets seen off the coast of Atlantic City.
The F-35 is notable for being $163 billion dollars over budget, seven years behind schedule, and plagued with design flaws. David Axe at Reuters, notes the plane’s single-engine design means it “can’t turn, can’t climb, can’t run”,[7] forcing the Pentagon to limit flights. Should these jets see real action, the USA is in trouble.
The remaining suspect has been grounded since 2003. The Concorde, a supersonic passenger jet, was mothballed after the Air France Flight 4590 crash in 2000, 9/11 making people think twice about flying, then Airbus’s decision to discontinue the plane altogether.
Could it have been a meteor? Nearly three years ago a 13,000 metric ton hunk of rock exploded over Chelyabinsk in the Urals. The explosion was estimated at 500 kilotons, blowing out windows, flattening a factory, and injuring over 1,000 Russians with its sonic boom and detonation over the city.
The Jersey Shore is no stranger to otherworldly visitors. On the 23rd of April, 1922 the Toms River beach patrol reported a fireball crashing into the water, generating huge waves. Here’s The Evening World‘s report from Monday, April 24, 1922:
The Coast Guard lookout was attracted by a bluish light in the sky and saw a ball of fire. It was accompanied by a roaring sound and a tremendous explosion occurred when the mass struck the water. An earth tremor was felt for a considerable area in and around Toms River.
Reports that the meteor had fallen on land were disproved. Headquarters of the Coast Guard along the New Jersey shore is at Asbury Park.
The meteor appeared about one-fourth the size of a full moon and was the largest even seen by those observerse who reported it. It seemed to start from about 45 degrees above the horizon and almost due south of New York.
It gets weirder with residents of Seaside Park talking about smelling the meteor after it crashed offshore. More recently, on April 18th, 1979 there were reports of a meteorite falling into Barnegat Bay near Lanoka Harbor about 20 minutes south of Toms River. Interesting to note both incidents happened around the time of the Lyrids meteor shower. 1922’s show was particularly intense according to Wikipedia.
So far there are no reports of a fireball offshore. There have been two notable daylight sightings of meteors over the past week. Calgary, Alberta recorded a fast-moving fireball over their city around 5 p.m. MST [8]. On Tuesday, Floridians bore witness to a daytime fireball [9] zooming into their state from southern Georgia’s airspace.
If this wasn’t America’s military, might it have been another country? Two hours before the booms echoed over New Jersey, the notorious Russian numbers station UVB-76 issued two cryptic broadcasts.
Synchronicity may also be afoot, with Thursday being the thirtieth anniversary of the space shuttle Challenger disaster heralding the end of the space age.
As for my own experience, a neighbor shared an update from the Ocean County Sheriff’s Department about a possible earthquake. At 2:14 p.m EST my house shook for a handful of seconds, but I didn’t feel the ground move. Nobody else I know saw, heard, nor felt anything so I take solace in the sheer volume of reports flooding Twitter.
Special thanks to the Astronomical Society of the Toms River Area, @mobios for the UVB-76 recording, and @AtlanticCity911 for the scanner clip.
- http://earthquake.usgs.gov/earthquakes/eventpage/us20004vbk#general_region
- http://06880danwoog.com/2016/01/28/boom/
- http://bnonews.com/news/index.php/news/id3454
- http://mobile.philly.com/beta?wss=/philly/news/science&id=366890161
- http://www.nj.com/news/index.ssf/2016/01/shaking_in_nj_was_likely_a_sonic_boom_usgs_says.html
- http://www.baltimoresun.com/news/maryland/bs-md-sonic-boom-20160128-story.html
- http://blogs.reuters.com/great-debate/2014/07/14/pentagons-big-budget-f-35-fighter-cant-turn-cant-climb-cant-run/
- http://calgary.ctvnews.ca/mysterious-streak-of-light-spotted-in-sky-over-calgary-1.2745309
- http://earthsky.org/space/daylight-meteor-over-southeastern-u-s-jan-24-2016