Earth’s atmosphere does not end anywhere near the edge of space: a ghostly hydrogen cloud called the geocorona stretches 630,000 kilometres out — far enough to envelop the Moon and make every lunar mission, technically, a journey through the outermost air of home

SOHO traced Earth's neutral-hydrogen geocorona beyond the Moon, but its density at lunar distance is only about 0.2 atom per cubic centimetre. The post Earth’s atmosphere does not end anywhere near the edge of space: a ghostly hydrogen cloud called the geocorona stretches 630,000 kilometres out — far enough to envelop the Moon and make every lunar mission, technically, a journey through the…