The European Space Agency announced Thursday it has re-established communication with a spacecraft that is part of its Proba-3 mission, after losing contact with the satellite a month ago.
Proba-3, which launched on a two-year mission in 2024, uses two spacecraft flying in precise formation to simulate a solar eclipse more than 60,00 kilometres (37,000 miles) above Earth.
Scientists have used this delicate dance to get a rare glimpse of the Sun’s little-known outer atmosphere, which is called the corona.
One satellite has a 1.4-metre (five-foot) shield that plays the role of the Moon in blocking the Sun’s light, while the other observes the corona from the shadow.
However something happened to the second spacecraft, which has the crucial coronagraph instrument, on February 14.
A chain reaction led to the spacecraft losing its orientation, causing its solar panel to face away from the Sun, draining the batteries.
The spacecraft then entered survival mode — it has been silently floating through space since.
However overnight “some miracle happened because we reconnected with the spacecraft,” ESA director Josef Aschbacher said on Thursday.
The other spacecraft — the one with the shield — had been “following and observing” its lost twin, he told a press conference held after an ESA Council meeting.
The lost spacecraft had been “tumbling” when an ESA team in Spain “saw that some sunlight is actually hitting the solar panels,” Aschbacher explained.
They seized the chance, using this small amount of power to re-establish a connection.
The spacecraft’s solar panel is now facing the Sun, allowing it to charge its batteries.
Next ESA experts will switch the instruments back on and carry out tests to find out how much damage has been done.
“Hearing back from the coronagraph is amazing news, and a great relief!” Proba-3 mission manager Damien Galano said in a statement.
The Sun’s corona, which is several million kilometres thick, still remains little understood. Invisible to the naked eye and telescopes, it is normally hidden by the bright light coming from the Sun.
While total eclipses on Earth last just minutes and only occur around 60 times a century, Proba-3 is capable of securing 10 to 12 hours of observations a week over two years, according to the ESA.
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