The mission Solar Orbiter, launched in February 2020, returns to the Land for a flyby before your main scientific mission to explore the Sun and its connection to "space weather."
During the flyby, Solar Orbiter –A mission developed by ESA in collaboration with NASA– must pass through the clouds of space debris that surround our planet, making this maneuver the most risky flyby so far for a scientific mission.
Solar Orbiter's flyby of Earth takes place on November 27. At 04.30 UTC, the spacecraft will be on its closest approach, just 460 kilometers over North Africa and the Canary Islands. This is almost as close as the orbit of the International Space Station.
The maneuver is essential to decrease the spacecraft's energy and align it for its next close pass from the Sun, but it carries a risk. The spacecraft must traverse two orbital regions, each of which is populated with space debris.
The first is the geostationary ring of satellites at 36,000 km, and the second is the collection of low Earth orbits at about 400 km. As a result, there is a small risk of collision. The Solar Orbiter operations team is monitoring the situation very closely and will alter the trajectory of the spacecraft if it appears to be in danger.
On the bright side, the flyby offers a unique opportunity to study the Earth's magnetic field. This is a topic of great interest because the magnetic field is the interface of our atmosphere with the solar wind, the constant “wind” of particles emitted by the Sun. Not only can solar wind particles penetrate the magnetic field and cause the aurora in our skies, but the atoms in our atmosphere can also get lost in space.
The flyby marks an important milestone for Solar Orbiter. From its launch in February 2020 to July of that year, the spacecraft was in its commissioning phase, during which scientists and engineers tested the spacecraft and its instruments, ESA reports.
From July 2020 until now, Solar Orbiter has been in the cruise phase. During this time, instruments in situ have been taking measurements of the solar wind and other conditions around the spacecraft, while remote sensing instruments designed to look at the Sun have been in their extended calibration and characterization mode.
However, now is the time to start operating the two sets of instruments together as the mission moves into the main science phase, and the anticipation is palpable. In March, the Solar Orbiter will make its second step close to the Sun, called perihelion. Its first perihelion took place in June 2020, and the spacecraft approached 77 million kilometers. This time, the Solar Orbiter will zoom within 50 million kilometers, providing a significant boost to the science that can be done.
This includes new views of the enigmatic "bonfires" that Solar Orbiter saw at the first perihelion. Campfires could hold clues to how the Sun's outer atmosphere is millions of degrees hot, while the surface is thousands, seemingly challenging physics because heat shouldn't be able to flow from a colder object to one. hotter.