NASA Satellites Capture Another Glimpse of the Spacecraft’s Most Frequently Visiting Comet
Comet 96P was detected again last month by NASA’s Solar Heliospheric Observatory (SOHO). The comet last visited back in 2012, but prior to that made appearances in 1996, 2002, and 2007, making it the most frequent cometary visitor to the spacecraft. It appeared in the lower right corner of SOHO’s view and was visible for five days before shooting off.
Simultaneously the comet shot through another view – that of NASA’s Solar and Terrestrial Relations Observatory (STEREO). It’s a very rare occurrence for the same comet to be seen at the same time from two different locations, and these new observations are the most comprehensive we’ve ever seen.
Moving forward, scientists will use these observations to discover more about the comet’s composition as well as how it interacts with the solar wind. Both observations succeeded in getting polarization measurements of the comet. These measurements enabled the scientists to gather details about the particles the light passed through.
The comet entered the bottom of STEREO’s view and crossed it diagonally before leaving on Oct. 28. Most of the corona has been suppressed in order to bring out the comet, leaving only the dynamic flow of the solar wind. NASA’s Goddard Space Flight Center/STEREO/Bill Thompson/Joy Ng
“Polarization is a strong function of the viewing geometry, and getting multiple measurements at the same time could potentially give useful information about the composition and size distribution of the tail particles,” said STEREO’s chief observer, William Thompson.
Comet 96P was first discovered back in 1986 by Dan Machholz. It’s also known as comet Machholz. It takes the comet approximately 5.24 years to orbit the Sun and at its closest point is just 11 million miles from the burning ball of gas.
When the comet made an appearance in SOHO’s view in 2012, astronomers found there to be tiny comet fragments nearby by it, suggesting that it’s still evolving. This comet is particularly of interest to scientists for two reasons. The first is that it has a strange composition and second because it’s the parent of a large group of comets. Taking a closer look at 96P will allow scientists to gain a deeper understanding as to its nature and origins.