Spacecraft
Carruthers Geocorona Observatory
Photographs the Earth's own outermost air. Above the atmosphere there is a thin halo of hydrogen, the geocorona, reaching far past the Moon and glowing faintly in ultraviolet; from L1 the whole of it fits in one frame, which is not true from anywhere nearer. It is named after George Carruthers, who put the first telescope on the Moon in 1972 and took the picture that showed the halo was there.
- Agency
- NASA
- Launched
- 2025-09-24 - still working
Path
The smallest of the three at L1, and on the same kind of loop. It is pointed back at the Earth rather than at the Sun, which costs it nothing in where it flies - the balance point is chosen for the steady view, and what the view is of is a matter for the instrument.
Everything the map shows is worked out in your browser from published orbital data - nothing on it is a stored picture of where things were.