Our part of the solar system has a spectacular new visitor, a comet that has been technically identified as C / 2020 F3 NEOWISE, but is more commonly simply called NEOWISE. This bright comet passed extremely close to the sun last week and is now even visible to the naked eye when it races from the sun to earth.
The comet is named after the mission that discovered it, a NASA mission to measure near-earth objects, the near-field wide-angle infrared survey explorer (NEOWISE). The mission first discovered the comet in March this year.
“In its discovery images, the comet NEOWISE appeared as a glowing, blurred point that moved across the sky, even if it was still quite far away. As soon as we saw how close it would get to the sun that crossed Mercury's orbit, we hoped it would do a good show, ”said Amy Mainzer, chief investigator at NEOWISE, in a statement.
An unprocessed image of the WISPR instrument on board NASA's Parker Solar Probe shows comet NEOWISE on July 5, 2020, shortly after it comes closest to the sun. The sun is outside the frame on the left. The faint grid pattern near the center of the image is an artifact of the way the image is created. The small black structure in the lower left of the image is caused by a speck of dust that rests on the lens of the imager NASA / Johns Hopkins APL / Marine Research Laboratory / Parker Solar Probe / Brendan Gallagher
This week, the comet was captured by NASA's Parker Solar Probe, which is currently in orbit around the sun and was able to image the comet with its WISPR (Wide Field Imager for Solar Probe) instrument. Although this instrument is primarily designed to take pictures of the sun and solar winds, it was able to capture the comet because of its high sensitivity, which allowed it to see the comet's tails.
NASA has released both the unprocessed image of WISPR and a processed version that shows more detailed information about the comet.
Processed data from the WISPR instrument on NASA's Parker Solar Probe shows more detailed information about the double tails of the comet NEOWISE, as seen on July 5, 2020. The lower, wider tail is the dust tail of the comet, while the thinner, upper tail of the comet is the ion tail. NASA / Johns Hopkins APL / Marine Research Laboratory / Parker Solar Probe / Guillermo Stenborg
The ability to image the comet in such detail has helped astronomers understand more about its properties. "From the infrared signature, we can see that the diameter is about 5 kilometers or 3 miles," said Joseph Masiero, deputy main researcher at NEOWISE, in the statement. “By combining infrared data with visible light images, we can see that the comet's nucleus is covered with sooty, dark particles that were left over from the birth of our solar system 4.6 billion years ago. "
The comet will be visible this weekend and early next week. If you want to search for the comet yourself, Sky and Telescope offers instructions on how to recognize NEOWISE from home.