Today, a decommissioned spacecraft will fall to the Earth today in a never-before-performed set of manoeuvres.
The Aeolus satellite was launched in 2018 by the European Space Agency (ESA) to measure the Earth’s winds from orbit.
The 1360-kg satellite has been effectively operating for the past five years, but it has run out of fuel and will return to Earth this week.
The satellite was supposed to naturally return via our atmosphere and was planned and built before any restrictions on ‘end-of-life’ disposal were in place.
ESA intends to guide the satellite through a controlled reentry into the atmosphere later today to guarantee that it does not endanger people or property on Earth.
When the spacecraft reaches an altitude of around 93 miles, the reentry process will commence. The satellite’s remaining fuel will be used to guide it into a controlled descent.
As of today, all four reentry manoeuvres have been completed successfully, and Aeolus is already skimming the top of our atmosphere, buffeted by heavier air – our planet’s protective barrier – in a preview of what’s to come tonight. The satellite is now flying at a height of less than 160 km.
However, a ‘major anomaly’ occurred last night that could have caused the assisted re-entry attempt to be aborted.
Since Aeolus wasn’t meant to be manoeuvred at such low altitudes flying through this part of the atmosphere is extremely challenging for it.
The satellite will then heat up as it enters the atmosphere, eventually burning up completely.
‘The UK Space Agency operates the UK’s re-entry warning service and has tasked our UK sensors to observe the re-entry,’ said Angus Stewart, head of space surveillance and tracking at the UK Space Agency.
‘If observations are obtained, these will be provided to ESA and the Inter-Agency Space Debris Coordination Committee (IADC) to support the re-entry analysis.’
The reentry is expected to occur over a remote stretch of the Atlantic Ocean.
According to the ESA, because populated areas make up such a small percentage of the Earth’s surface, the chances of a re-entry causing any harm are extremely low.
The overall risk of reentering satellites is already extremely minimal. For example, the danger of being hit by space debris is approximately three times smaller than the risk of being hit by a falling meteorite.ver a distant section of the Atlantic Ocean.