comets tagged posts

Distant ‘Space Snowman’ unlocks mystery of how some Dormant Deep Space Objects become ‘Ice Bombs’

This image was taken by NASA’s New Horizons spacecraft on Jan. 1, 2019 during a flyby of Kuiper Belt object 2014 MU69. Photo by NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

A new study is shaking up what scientists thought they knew about distant objects in the far reaches of the solar system, starting with an object called the space snowman.

Researchers from Brown University and the SETI Institute found that the double-lobed object, which is officially named Kuiper Belt Object 486958 Arrokoth and resembles a snowman, may have ancient ices stored deep within it from when the object first formed billions of years ago. But that’s just the beginning of their findings.

Using a new model they developed to study how comets evolve, the researcher...

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Numerical Simulations of Planetesimal Formation Reproduce Key Properties of Asteroids, Comets

Numerical simulations of planetesimal formation reproduce key properties of asteroids, comets
Comparison between the predictions by Polak and Klahr for the mass distribution of asteroids (red circles), compared with observations (white circles). The horizontal axis shows the size of the asteroids in question, and the vertical axis shows the fraction of the total mass of the pebble cloud that ends up in asteroids larger or equal to the chosen size value. If the total mass were to end up in a single asteroid, that asteroid would have been 152 km in diameter. Both in the prediction and according to the observations, 84% of the total asteroid mass ends up in objects between 90 km and 152 km in diameter. Overall, the primordial asteroids follow a normal (Gaussian) distribution (blue line) in mass with a most likely size of 125 km...
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Rare 4,000-year Comets can cause Meteor Showers on Earth

The meteoroid stream of long-period comet Thatcher from CAMS data. Outer blue ellipse is the orbit of Neptune. Photo: P. Jenniskens / SETI Institute

Researchers report that they can detect showers from the debris in the path of comets that pass close to Earth orbit and return as infrequently as once every 4,000 years.

Comets that circle the Sun in very elongated orbits spread their debris so thin along their orbit or eject it out of the solar system altogether that their meteor showers are hard to detect. From a new meteor shower survey published in the journal Icarus, researchers now report that they can detect showers from the debris in the path of comets that pass close to Earth orbit and are known to return as infrequent as once every 4,000 years.

“This creates a situational ...

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Experiments trace Interstellar Dust back to Solar System’s Formation

This cometary-type interplanetary dust particle was collected by a NASA stratospheric aircraft. Its porous aggregate structure is evident in this scanning electron microscope image. Credit: Hope Ishii/University of Hawaii

This cometary-type interplanetary dust particle was collected by a NASA stratospheric aircraft. Its porous aggregate structure is evident in this scanning electron microscope image. Credit: Hope Ishii/University of Hawaii

Chemical studies show that dust particles originated in a low-temperature environment. Experiments conducted at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) helped to confirm that samples of interplanetary particles – collected from Earth’s upper atmosphere and believed to originate from comets – contain dust leftover from the initial formation of the solar system.

An international team, led by Hope Ishii, a researcher at the University of Hawaii at Manoa (UH Manoa), studied the particles’ chemical composition using infrared light at Ber...

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