Thursday, August 19, 2021

Great Balls of Fire

NASA's Center for Near Earth Object Studies (CNEOS) has published an interactive map which shows the impact energy of all the meteors detected by government sensors between 1988 and 2021. Each fireball event is shown on the map by its marker's size and color.

The Fireballs Reported by US Government Sensors map allows you to explore the impact energy and the date & time of each recorded fireball event. The large fireballs shown on the map were detected by government sensors such as the lightning sensors on GOES weather satellites. When a meteor enters the Earth’s atmosphere some of its kinetic energy is converted into radiated energy. This optical flash is what we can see from Earth. This flash is also able to be detected by the lightning sensors on weather satellites. The size of the optical flash also allows us to calculate the fireball's kinetic energy and the original size of the object before it entered our atmosphere. 

The big red dot over Russia on the map is an asteroid spotted over Chelyabinsk in February 2013. This asteroid was calculated to have originally been 20 meters across. The map only shows the largest fireball events, involving asteroids measuring at least one meter across. As well as publishing this interactive map CNEOS has also published the data on these fireball events, including the date and time of each event, the radiated energy, the calculated total impact energy and the latitude and longitude of each fireball event. If you want you can download this data in CSV format and make your own fireball map.

NASA’s also maintains a network of all-sky meteor cameras. The NASA All-sky Fireball Network consists of 17 cameras in the United States.You can view the locations of fireballs recorded by the All-sky Fireball Network on the NASA Skyfall Database

The blues arrows on the NASA Skyfall Database map show the 'Chicken Little Trajectory' of each spotted fireball over the United States. If you click on one of these blue arrows you can learn more about the indicated  fireball event, including information on the fireball's trajectory & speed, the number of eye witnesses, and the date and time of the event.

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