The loud boom heard across Massachusetts and Rhode Island on May 30 was not thunder, an earthquake or a blown transformer. It was a meteor traveling approximately 42,000 miles per hour.
That cosmic close call provided a timely opening for “Asteroids, Meteors, and Cosmic Close Calls,” presented by Dr. Sarah Caudill on Friday, July 24, at the Marion Natural History Museum.
Elizabeth Leidhold, executive director of the 154-year-old museum, introduced Caudill, associate professor of physics at UMass Dartmouth and member of the UMass-URI Gravity Research Consortium. Caudill’s research includes gravitational waves, black holes and neutron stars.
Caudill recalled hearing the May 30 boom from her kitchen.
“I thought it was thunder, but I thought it was odd because the sun was out,” she said. “Then I thought, ‘Maybe it’s construction down the street.'”
The actual cause was a meteor about 5 feet in diameter and weighing an estimated 5.6 metric tons. It fragmented roughly 40 miles above northeastern Massachusetts and southeastern New Hampshire, producing the sonic boom heard across the region. Surviving pieces are believed to have fallen into Cape Cod Bay.
NASA estimated that the meteor released energy equivalent to about 230 tons of TNT as it broke apart. Much of that energy was dispersed as light, heat and sound while the object traveled through the atmosphere. No injuries or property damage were reported.
Caudill used the event to explain some commonly confused terms. A meteoroid is a relatively small rock traveling through space. When it enters Earth’s atmosphere and produces a visible streak, it becomes a meteor. Any piece that survives and reaches the ground is called a meteorite. Asteroids are larger, rocky or metallic objects orbiting the sun.
The May 30 object is believed to have contained a significant amount of iron, explaining how an object roughly as tall as Caudill could weigh more than 5 tons.
Asteroids can be made of metal, silicate rock or carbon-rich material. Some contain water-bearing minerals and amino acids, the building blocks of proteins. Scientists believe asteroids and comets may have delivered water and some of the essential ingredients for life to early Earth.
Caudill also explained that meteor showers come from debris left by comets. The “shooting stars” visible from Earth can be produced by particles no larger than grains of sand.
Small objects like the one over New England are difficult to detect before they reach the atmosphere. Larger asteroids capable of causing serious damage are generally easier for astronomers to identify and track – and such impacts are far less common.
For those interested in watching the night sky, Caudill recommended the American Meteor Society’s online Meteor Shower Calendar, which lists upcoming showers and the best times to see them.
The remnants of the May 30 meteor may now rest about 100 feet beneath Cape Cod Bay, making recovery difficult. For New England residents who heard it, the event offered a rare reminder that Earth is not separate from the activity of the solar system.
Sometimes, we can even hear it.
By Jeanne Hopkins