- Asteroid Terrestrial-Impact Last Alert System (ATLAS) discovered asteroid 248370 was active on 7 July
- Astronomers believe that celestial bodies are icy and carry dust like comets, but have the orbit of an asteroid
- Its tail is over 50,000 miles long, which is more than three times the distance from Earth to the Moon, we’re sure?
- It joins the group of objects known as main-belt comets with characteristics of both comets and asteroids.
- Understanding main-belt comets could help scientists better understand how water enters Earth’s atmosphere
What do you call an asteroid when it’s not an asteroid? A comet – that too is an asteroid.
Astronomers have determined that a newly discovered celestial object has a frozen core like a comet, but with an orbit more similar to that of an asteroid.
The Asteroid Terrestrial-Impact Final Warning System (ATLAS) survey discovered asteroid (248370) 2005 QN 137, which was active on July 7, 2021.
“It fits into the physical definitions of a comet, because it is icy and is ejecting dust into space, even though it also has an asteroid’s orbit,” said Henry Hsieh, a researcher at the Planetary Science Institute. Presentation on Monday.
‘This duality and blurring of the boundary that were previously treated as two completely different types of objects – asteroids and comets – is a key part of what makes these objects so interesting.’
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Astronomers believe that asteroid 248370 is icy and expels dust like a comet, but its orbit is more in line with that of an asteroid. “This dichotomy and blurring of the boundary between the first two completely different types of objects is an important part of what makes these objects so interesting,” said Henry Hsieh, a researcher at the Planetary Science Institute.
Of the more than half a million known main-belt asteroids, 248370 is one of only eight confirmed to have been active more than once.
‘This behavior strongly indicates that its activity is due to the sublimation of the icy material,’ Hsieh said.
That ‘icy substance’ suggests that it is also a comet.
A main-belt comet, to be precise – one of only about 20 celestial bodies suspected or confirmed to be, Hsieh said, ‘some that have so far only been observed to be active once.’
The hybrid, which Hsieh calls a ‘main-belt comet’, was discovered hidden among asteroids in the inner solar system.
A chart showing how 248370’s orbit differs from that of conventional comets such as Halley.
Conventional comets, such as Halley’s, spend most of their time in the cold outer solar system, away from the Sun.
Hsieh presented his findings today at the annual meeting of the American Astronomical Society’s Division for Planetary Sciences.
‘248370 can be considered as both an asteroid and a comet, or more specifically, a main-belt asteroid that has recently been recognized as a comet,’ he said.
They found that the size of the object’s nucleus – the solid object at the ‘head’ of the comet – was about two miles across, and that its tail was about 900 miles wide.
In July, the tail was over 450,000 miles long.
To put this in more perspective, if the tail were the length of a football field, it would be only seven inches wide, with a head only half a millimeter.
Hsieh said, “This extremely narrow tail tells us that the dust particles are barely floating through the nucleus at extremely slow speeds and that the flow of cometary gas that normally carries dust from comets into space is extremely weak.” Is.”
Normally such slow motion would make it harder for dust to escape the gravity of the comet’s nucleus, so Hsieh theorized ‘something else’ was helping to shed the dust.
“The nucleus must be spinning so fast that it is helping to eject dust into space that has been partially lifted up by escaping gas,” he said, adding that more information was needed to confirm the motion of the comet’s nucleus. More observation was needed.
Humoral activity is generally thought to be caused by the transformation of ice into gas.
Most comets spend most of their time at the cold outer edge of the Solar System, beyond the orbit of Neptune, with long orbits that come only for short periods of time near the Sun or Earth.
Most comets spend most of their time at the cold outer edge of our solar system, beyond the orbit of Neptune, with long orbits that come only for short periods of time near the Sun or Earth.
“During the time they are close enough to the Sun, they heat up and release gas and dust as a result of ice sublimation, creating the hazy appearance and spectacular tail often associated with comets,” Haseh said.
In contrast, main-belt asteroids orbit in the hot inner solar system, between the rotations of Mars and Jupiter.
Astronomers believe that they have been, at least for the last 4.6 billion years, any ice that has been melting longer.
Main-belt asteroids orbit in the hot inner Solar System. Astronomers believe that they have been, at least for the last 4.6 billion years, any ice that has been melting longer.
But as Hsieh and UCLA astronomer David Jew have determined, there are some objects, main-belt comets, that defy these clear distinctions.
This is important because a large part of Earth’s water is believed to have been delivered through asteroid impacts when the planet was being formed.
Since these hybrid comet-asteroids are likely to still contain ice, Hsieh said, they could help test that theory and provide clues about the origins of life on Earth.
Explained: The difference between an asteroid, meteorite and other space rocks
One small star There is a large chunk of rock left over from collisions or the early Solar System. Most are located between Mars and Jupiter in the main belt.
a comet Ice is a rock covered with methane and other compounds. Their orbits take them far beyond the Solar System.
a Meteor Astronomers call a flash of light in the atmosphere when debris burns up.
This debris only a. is referred to as Meteorite. Most are so small that they evaporate into the atmosphere.
If any of these…