In the early hours of Sunday, September 4, Solar Orbiter flew by
Fortunately, there was no damage or no negative effects on the spacecraft. Indeed, the ESA-
So far, Solar Orbiter has been confined to the same plane as the planets, but from February 2025 onwards, each encounter with Venus will increase its orbital inclination, causing it to ‘leap’ up from the plane of the Solar System to get a view of the Sun’s mysterious polar regions.
This third flyby of Venus took place on Sunday at 01:26
Its distance from Venus, angle of approach, and velocity were all carefully planned to get the precise desired effect from the planet’s large gravitational pull – getting the spacecraft closer to the Sun than ever before.
“The close approach went exactly to plan, thanks to a great deal of planning from our colleagues in Flight Dynamics and the diligent care of the Flight Control Team,” explains Jose-Luis Pellon-Bailon, Solar Orbiter Operations Manager.
“By trading ‘orbital energy’ with Venus, Solar Orbiter has used the planet’s gravity to change its orbit without the need for masses of expensive fuel. When it returns to the Sun, the spacecraft’s closest approach will be about 4.5 million km (2.8 million miles) closer than before.”
Understanding particles that pose a radiation risk
Data beamed back to Earth since Solar Orbiter encountered the solar storm shows how its local environment changed as the large CME whooshed by. Although some instruments had to be turned off during its close approach to Venus, in order to protect them from stray sunlight reflected off of the planet’s surface, Solar Orbiter’s ‘in situ’ instruments remained on, recording an increase in solar energetic particles, among other things.
Particles, mostly protons and electrons, but also some ionized atoms like Helium, are constantly emitted by the Sun. When particularly large flares and ejections of
Goodbye, halo?
This recent CME illustrates a difficulty in space weather observations. As seen in this footage from
It is tricky to determine if coronal mass ejections are coming towards Earth or moving away when viewed from Earth, because in both cases it appears to be expanding. One of the many benefits of the coming Vigil mission is that by combining the images taken from Earth’s direction and Vigil’s position at the ‘side’ of the Sun, the fifth Lagrange point, it will be easy and reliable to distinguish between an oncoming or departing storm.
Space weather gets deep
The Sun wields its influence on all the bodies of the Solar System. It’s the reason why no life could survive on the inner planets, as the sun makes their temperatures too hot and stripped away their atmospheres long ago.
As we venture from Earth to the Moon, it’s vital that we understand how space weather can affect human bodies, robots, communication systems, and plants and animals.
As well as a wide range of tools to understand the Sun’s effect on Earth’s infrastructure, ESA’s Space Weather Service Network currently alerts teams flying missions throughout the Solar System of extreme space weather, with forecasts for Mercury, Venus, and