Sciency Thoughts: Maine

Showing posts with label Maine. Show all posts

Thursday, 2 June 2022

Fireball meteor over Maine.

The American Meteor Society has received reports of a bright fireball meteor being seen over Maine slightly after 10.15 pm local time on Wednesday 1 June 2022 (slightly after 2.15 am on Thursday 2 June, GMT). People witnesses observing the event from Connecticut, Massachusetts, Maine, New Hampshire, New York, Quebec and Vermont. A fireball is defined as a meteor (shooting star) brighter than the planet Venus. These are typically caused by pieces of rock burning up in the atmosphere, but can be the result of man-made space-junk burning up on re-entry.

The 1 June 2022 Fireball seen from Orrington, Maine. Daniel Philips/American Meteor Society/YouTube.

Objects of this size probably enter the Earth's atmosphere several times a year, though unless they do so over populated areas they are unlikely to be noticed. They are officially described as fireballs if they produce a light brighter than the planet Venus. The brightness of a meteor is caused by friction with the Earth's atmosphere, which is typically far greater than that caused by simple falling, due to the initial trajectory of the object. Such objects typically eventually explode in an airburst called by the friction, causing them to vanish as an luminous object. However, this is not the end of the story as such explosions result in the production of a number of smaller objects, which fall to the ground under the influence of gravity (which does not cause the luminescence associated with friction-induced heating).

Heat map showing areas where sightings of the meteor were reported (warmer colours indicate more sightings), and the apparent path of the object (blue arrow). American Meteor Society.

These 'dark objects' do not continue along the path of the original bolide, but neither do they fall directly to the ground, but rather follow a course determined by the atmospheric currents (winds) through which the objects pass. Scientists are able to calculate potential trajectories for hypothetical dark objects derived from meteors using data from weather monitoring services.

Witness reports can help astronomers to understand these events. If you witness a fireball-type meteor over the US you can report it to the American Meteor Society here.

Wednesday, 29 July 2020

Woman dies in Shark attack off the coast of Maine.

A woman has died in a Shark attack near Portland in Maine on Monday 27 July 2020. Julie Holowach, 63, from New York, who had recently retired to the area, was swimming about 18 m off shore near Mackerel Cove on Baily Island, with her daughter, when she was attacked by a Great White Shark, Carcharodon carcharias, which dragged her below the water before releasing her and withdrawing, a pattern typical of Great White attacks. Ms Holowach was helped ashore by two kayakers but subsequently died of her injuries; she was later found to have a tooth embedded in her leg, which has been used to confirm the nature of the Shark which attacked her. This is only the second Shark attack ever recorded in Maine; the first being an attack on a diver by a Porbeagle Shark, Lamna nasus, in 2010, which did not result in any injury.

Julie Holowach, 63, killed by a Great White Shark off the coast of Mackerel Cove, Maine, on 27 July 2020. Julie Holowach/Facebook.

Despite their fearsome reputation, attacks by Sharks are relatively rare, and most attacks on Humans by Great White Sharks are thought to be mistakes. The species feeds principally on Marine Mammals, which we superficially resemble when we enter the water, gaining the majority of their nutrition from the thick adipose (fat) layers of these animals, which we lack. Due to this, when Great Whites do attack Humans these attacks are often broken off without the victim being consumed. Such attacks frequently result in severe injuries, but are seldom immediately fatal, with victims likely to survive if they receive immediate medical attention.

A Great White Shark, Carcharodon carcharias. Mauricio Hoyos/Florida Museum.

Wednesday, 17 October 2012

Earthquake under Maine shakes New England.

On Tuesday 16 October 2012, slightly after 7.10 pm local time (slightly after 11.10 pm, GMT) the United States Geological Survey recorded a Magnitude 4.0 Earthquake 5 km underground, roughly 30 km southwest of Portland, Maine. This is not an especially large quake, but it was quite shallow and is far larger than the area is used to, leading the USGS estimate that there was a 24% chance of the quake resulting in at least one fatality. There have not been any reports of damage or casualties, but the quake appears to have caused widespread alarm over much of New England.

The location of the 16 October 2012 Earthquake. Google Maps.

Earthquakes in Maine are an uncommon occurrence, but they do occur, with six Earthquakes of Magnitude 4.0 or greater being recorded in the twentieth century, the largest being the Magnitude 4.8 Bowmantown quake of 1973. The precise cause of these quakes is unclear, though they are thought to be associated with tectonic stresses in the Appalachian Mountains. The state is cross-cut from north-to-south by a number of ancient faults associated with the formation and breakup of the ancient supercontinent of Pangea, between 300 and 200 million years ago, though no sign of modern movement on these faults has been discovered.

Witness accounts of quakes can help geologists to understand these events and the rock structures that cause them. If you felt this quake you can report it to the USGS here.

Follow Sciency Thoughts on Facebook.