Esa / NASA solar orbiters currently make a series of swings around the solar system so that it can be closer to the final target, the sun. While the scientific laboratory runs, it has the opportunity to investigate several other interesting subjects, also including comets, recently has a close meeting with.
Comets are a sponge most of the ice warmly as they approach the sun and remove the gas that forms a typical tail. Usually, they have very elliptical orbits (i.e., very oval), and they can come from the depths away from the solar system, change very little from time to time. Remembering that, the opportunity to investigate the closing comet is very exciting, because it gives scientists the opportunity to catch a glimpse of what might be seen by the solar system.
Solar orbiters pass through the tail of one comet like that, called Comet C / 2021 A1 Leonard, for several days around December 17, 2021. Esa has now shared more information about comets and what researchers expect to learn from it.
The solar orbiter team can predict when the orbiter will pass through the comet tail by looking at data about solar wind, which is the flow of energetic particles released by the sun. By entering data on solar wind into the program to model the spacecraft and comet orbit, they can see when the solar orbiter will intersect the tail of the comet.
The team uses a series of instruments on solar orbiters called solar wind analyzer (SWA) to detect what chemicals are on the tail of the comet, find oxygen and carbon ions, molecular nitrogen, and carbon dioxide molecules, and maybe water. Experts can also see the way the sun winds affect the magnetic field around the comet, which is dragged out of the sun’s magnetic field.
This is the second time the solar orbiter has approached a comet, because it also passed the tail of the comet at 2020. This time around, more solar orbiter instruments are online and ready to observe, collect additional data that will help astronomers improve their understanding of comets.
“This kind of additional science is always an interesting part of the space mission,” said the ESA project scientist for the Solar Orbiter Daniel Müller. “When Comet Atlas Crossing is predicted, we are still calibrating their spacecraft and instruments. Also, the comet is fragmented before we get there. But with Comet Leonard we are truly ready – and the comet is not messy.”
With the meeting it was finished, solar orbiters would continue to circle closer to the sun, making the nearest pass until now in March 2022 around 30 million miles.