The American Meteor Society has
received reports of a bright fireball meteor being seen off the Atlantic coast of the US, slightly after 6.05 pm Eastern Standard Time (slightly after 11.05 pm GMT) on Sunday 14 March 2021
(about 2.05 am on Thursday 4 January GMT). Sightings were reported from Connecticut, Delaware, Florida, Maine, Maryland, Massachusetts, New Jersey, North Carolina, New York, Ohio, Ontario, Pennsylvania, Rhode Island, Vermont, and West Virginia, with the object travelling from south to north along the coast, entering the atmosphere somewhere to the east of Delaware and vanishing to the south of Long Island. 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 14 February 2021 fireball meteor seen from St Mary's City in Maryland. Brian Haislip/American Meteor Society.
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.
See also...
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