A Mission of Gravity

When invaluable research equipment is lost on the planet Mesklin, astronaut Charles Lackland is dispatched to the planet's surface to retrieve it. He is aided by the creature Barlennan, a native Mesklinte, and the crew of Barlennan's ocean-going vessel. But Lackland and his alien companions face formidable challenges on the planet, most importantly extreme gravitational conditions. These conditions make Mesklin a ripe region for scientific research as well as a fascinating setting for a page-turning adventure story.