Reply To: Eclipses and Transits

Forums Sun Eclipses and Transits Reply To: Eclipses and Transits

Nick James

At perihelion the Earth’s umbra extends around 1.4 million km away so, as Dominic says, you would only see an annular eclipse from L2 which is around 1.5 km outward from the Sun. Eclipses are really bad things for spacecraft which rely on solar arrays for power so the outbound trajectory will avoids the Earth’s shadow wherever possible. L2 is gravitationally unstable and so spacecraft don’t actually sit at the Lagrange point itself but orbit in a halo around it with relatively frequent small thruster burns to keep them on station. We’ll have another opportunity to watch a spacecraft heading out to L2 when ESA’s Euclid gets launched on a Falcon 9 at the start of July.

Back on topic though. Could those additional items be added to the forum topics list?