Comet NEOWISE Was Spiraling and Spinning as it Passed by Earth

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Earlier this week, we shared an image of Comet NEOWISE (C/2020 F3) taken by the Hubble Space Telescope. And now, here are a group of images from the 8.1-metre Gemini North telescope in Hawaii. Like Hubble, Gemini North focused in on the comet's nucleus and coma, instead of its stunning, gossamer tails. But Gemini zoomed in and caught something Hubble didn't: Comet NEOWISE was rotating, which created a spiraling stream of molecular gas.

The close-up observations, led by Michal Drahus and Piotr Guzik of Jagiellonian University in Krakow, who were looking to try and see and study the rotational dynamics of the comet. Despite limitations imposed by the comet's proximity to the Sun, the researchers were able to confirm a 7.5-hour rotation period by measuring the spiral outflow of molecular gas as NEOWISE spun about.

Here's a timelapse video created by all the images taken by the team at Gemini North:

The prevailing notion is that most comets "release gasses in geyser-like jets and that is what researchers think is happening in the Gemini images," the National Science Foundation's NOIRLab said in a description. NOIRLab is US national center for ground-based, nighttime optical and infrared astronomy. "As the vaporized material erupts from the comet its rotation causes it to appear to spiral outward, much like the water from a spinning garden hose. The very same material impacts the comet's rotation causing its nucleus to spin-up or spin-down, though for most comets, the effect is too weak to detect."

In another set of impressive ground-based observations, an amateur astrophotographer from Germany, Bernd Gährken, was also able to capture some of the rotation as well.

Gährken was able to see the details of the spiral rotation, and he created a gif animation:

You can see more of his Comet NEOWISE images at his website.

Astronomers will certainly be studying Comet NEOWISE's fascinating pass by our planet for quite some time!

Hat tip to Daniel Fischer (cosmos4u) on Twitter

Nancy Atkinson

Nancy Atkinson

Nancy Atkinson is a space journalist and author with a passion for telling the stories of people involved in space exploration and astronomy. She is currently retired from daily writing, but worked at Universe Today for 20 years as a writer and editor. She also contributed articles to The Planetary Society, Ad Astra (National Space Society), New Scientist and many other online outlets.

Her 2019 book, "Eight Years to the Moon: The History of the Apollo Missions,” shares the untold stories of engineers and scientists who worked behind the scenes to make the Apollo program so successful, despite the daunting odds against it. Her first book “Incredible Stories From Space: A Behind-the-Scenes Look at the Missions Changing Our View of the Cosmos” (2016) tells the stories of 37 scientists and engineers that work on several current NASA robotic missions to explore the solar system and beyond.

Nancy is also a NASA/JPL Solar System Ambassador, and through this program, she has the opportunity to share her passion of space and astronomy with children and adults through presentations and programs. Nancy's personal website is nancyatkinson.com