ISON Stopped Making Dust Just Before It Passed By The Sun And Disintegrated

Last year’s Thanksgiving adventure for astronomers happened when Comet ISON passed within 1.2 million kilometres (750,000 miles) of the Sun. While many people were hoping the comet would stick around and produce a good show, the comet disintegrated despite a brief flare-up shortly after passing perihelion.

Scientists have just modelled the production of dust on the comet and concluded there was a “violent outburst” that happened 8.5 hours before closest approach, when the comet spewed out 11,500 tonnes (12,765 tons) of material.

“It is most likely that the final break-up of the nucleus triggered this eruption, abruptly releasing gas and dust trapped inside the nucleus,” stated Werner Curdt from the Max Planck Institute of Solar System Research, who was the lead researcher on the project. “Within a few hours the dust production stopped completely.”

Because the last few parts of the comet’s encounter were obscured by an occulting disk on the Large Angle and Spectrometric Coronagraph on the Solar and Heliospheric Observatory (SOHO), astronomers decided to model the encounter based on other data they gathered before and after.

Comet ISON captured in an image from the Solar and Heliospheric Observatory (SOHO)’s Solar Ultraviolet Measurements of Emitted Radiation (SUMER) instrument. Credit: MPS

They did have one source of data, which was another instrument called the Solar Ultraviolet Measurements of Emitted Radiation (SUMER). It’s usually used to investigate plasma activity on the sun and not faint comets, but the scientists felt it could be repurposed. T

hey switched modes on the instrument and captured the tail in far ultraviolet light, light “emitted from the solar disc and reflected by the dust particles into space,” the European Space Agency stated.

Then they compared what they saw with computer simulations, coming up with the dust estimations.

The paper is available in the journal Astronomy & Astrophysics and also in preprint version on Arxiv.

Source: European Space Agency

Elizabeth Howell

Elizabeth Howell is the senior writer at Universe Today. She also works for, Space Exploration Network, the NASA Lunar Science Institute, NASA Astrobiology Magazine and LiveScience, among others. Career highlights include watching three shuttle launches, and going on a two-week simulated Mars expedition in rural Utah. You can follow her on Twitter @howellspace or contact her at her website.

Recent Posts

DART Impact Seen by Hubble and Webb

What happens when you whack a little asteroid with an even littler spacecraft? People around…

1 hour ago

NASA and SpaceX Will Study Low-Cost Plan to Give Hubble a Boost

NASA and SpaceX say they'll conduct a feasibility study into a plan to reboost the…

1 hour ago

The First Telescope Images of DART's Impact are Starting to Arrive

The ESA just released a video that shows the DART mission impacting the double-asteroid system…

3 hours ago

Robots Might Jump Around to Explore the Moon

LEAP (Legged Exploration of the Aristarchus Plateau) is a mission concept study, funded by ESA,…

9 hours ago

Innovation to combat space debris – Chinese scientists introduce drag sail

Scientists at the Shanghai Academy of Spaceflight Technology (SAST) have devised an ingenious way to…

12 hours ago

Alaska Has New Lakes. Unfortunately, They’re Releasing a lot of Methane

A NASA scientist is finding newly formed lakes in Alaska that are belching greenhouse gases…

22 hours ago