Breaking

ESA’s Solar Orbiter Spacecraft Is Skimming Earth for a Gravity Assist – And It’s One of the Riskiest Planetary Flybys Ever - SciTechDaily
Nov 27, 2021 2 mins, 37 secs

Artist’s impression of Solar Orbiter making a flyby at Earth.

The chance that ESA’s Solar Orbiter spacecraft will encounter space debris during its upcoming Earth flyby is very, very low.

That there is this risk at all highlights the mess we’ve made of space – and why we need to take action to clean up after ourselves.

During the upcoming flyby, Solar Orbiter is estimated to pass just 460 km from Earth’s surface at its closest approach – about 30 kilometers above the path of the International Space Station.

It will travel twice through the Geostationary ring at 36 000 kilometers from Earth’s surface and even through low-Earth orbit, below 2000 kilometers – two regions littered with space junk.

Before we worry too much, let’s start by pointing out that the chance of Solar Orbiter being struck by debris is very, very, very small.

Earth observation missions spend their entire life in low-Earth orbit – the most debris-filled region of space, and while they perform ‘collision avoidance maneuvers’ a few times per year, Solar Orbiter will spend only a few minutes here as it heads towards closest approach and then leaves again, onward to Venus.

However small the risk, collisions with debris at low-Earth altitudes do happen.

Hubble, the NASA/ESA Space Telescope, has spent 31 years in Earth orbit at an altitude of around 547 kilometers.

ESA’s Space Debris Office also performed a collision risk analysis for this flyby as the spacecraft passed through Geostationary orbit, although it flew well above the debris-filled low-Earth orbit.

While the risk to Solar Orbiter during its upcoming Earth flyby is small, it’s still “non-zero”.

It didn’t face this risk as it swung by Venus, nor did ESA’s Space Debris Office have to perform collision risk analysis as BepiColombo recently zipped by Mercury, or when Cassini–Huygens flew by Jupiter.

Past Earth flybys, for example, when Cassini/Huygens flew by Earth in 1999, as Rosetta returned three times in 2005, 2007 and 2009, and Juno swung by in 2013, there were fewer satellites, fewer debris, and no ‘mega constellations’ in orbit.

ESA’s Space Debris Office recently began risk assessments based on Solar Orbiter’s trajectory and the expected position of cataloged objects in orbit around Earth, providing a collision probability for any specific close approaches.

Space might seem an empty, vast expanse, but satellites in Earth’s orbit face the constant risk of collision – with other satellites, dead or alive, or with fragments of debris.

For each of the Sentinel missions in Earth orbit, a collision avoidance maneuver is performed about once every five to six months when the ‘miss distance’ with another object is considered too risky.

Once Solar Orbiter comes up from low-Earth orbit and passes above geostationary orbit it is out of the risk zone.

While Solar Orbiter zips by, passing just momentarily through Earth’s orbital highways, it’s an important reminder that the space debris problem is unique to Earth, of our own making, and ours to clean up.

RECENT NEWS

SUBSCRIBE

Get monthly updates and free resources.

CONNECT WITH US

© Copyright 2024 365NEWSX - All RIGHTS RESERVED