The Solar Orbiter of the European Space Agency (ESA) has just carried out its first flight over Venus without problems. It happened at 12:39 GMT on December 27th, 2020. As the distance to Earth during the maneuver was about 231 million kilometers, the radio signals that we could send to give you orders would take 13 minutes, so it have executed the flight in autonomous mode.
Going into orbit around the Sun at a shorter distance than the Earth is complicated because any probe we send there initially shares our planet’s orbital speed, about 101,000 kilometers per hour, and we do not have any rocket capable of slowing it down sufficiently. So the Solar Orbiter is going to use Earth’s gravity one time and Venus’ gravity another eight times to slow it down. This will allow it to get as close as 0.28 astronomical units to the Sun, about 42 million kilometers from the Earth’s 150. In June 2020 it made its first approach to the Sun.
It will also use the gravitational assistance to leave the ecliptic plane. By 2025 it will be in an orbit with 17º of inclination that will increase until it reaches 33º in 2029. This will allow it to study the poles of the Sun as never before.
The mission will try to help us understand how the Sun creates and influences the heliosphere, the large plasma bubble that surrounds the entire Solar System and influences its planets. It will concentrate on four main areas of research:
- Solar Wind: What drives the solar wind and the acceleration of solar wind particles?
- Polar Regions: What happens in the polar regions when the solar magnetic field reverses its polarity?
- The Magnetic Field: How is the magnetic field generated within the Sun and how does it propagate through the Sun’s atmosphere and into space?
- Space weather: How do sudden events like flares and coronal mass ejections impact the Solar System? How do solar flares produce the energetic particles that lead to extreme space weather on Earth?
But the scientific part of the mission will not begin until late 2021. Although during the Venus flyover several instruments of the Solar Orbiter were turned on to study the magnetic, plasma and particle environment around Venus*.
The data obtained will be complemented with data from NASA’s Parker Solar Probe and the Daniel K. Inouye Telescope to give us an understanding of the Sun that we have not had before.