Summaries

Synopsis

The book starts off in the year 2177 when a metallic asteroid impacts in northern Italy, killing 600,000 and wiping out incalculable cultural artifacts. Responsively, the Earth creates SPACEGUARD to identify and track every single object in the Solar System.

This comes in handy when SPACEGUARD detects the approach of a new unknown object from extrasolar space, in the year 2130. It's an academic curiosity in the world of astronomy, so they name it Rama instead of a number ID. It's assumed to be a natural object until a flyby of a cluster of robot probes shows that is it actually a geometrically perfect cylinder twenty kilometers long. Gravimetric readings during the flyby indicate without a doubt that it is hollow. Mankind is about to get a very large unexpected guest.

Rama is moving fast and falling toward the Sun. It may even burn up if it gets too close. SPACEGUARD detected it outside the orbit of Jupiter. By the time the space ship Endeavour is able to catch up to Rama a few weeks later, it is inside the orbit of Venus. Endeavour is a large ship with over 50 people on board, a diverse crew of experts, but they have only 3 weeks to investigate the entire alien ship before they get too close to the Sun and have to take off and escape the heat.

Endeavour finally touches down on the forward end of the giant cylinder. The Commander, Norton, makes an EVA and quickly finds the control to the airlock door, which opens right up and allows the humans to enter. Easy! ... Too easy...

Meanwhile, on the Moon, an emergency committee is formed to deal with the implications of Rama and advise the far-off Commander Norton. Earth and the colonies on several planets and moons of the Solar system are represented. They vote to approve the exploration of the interior of Rama. It appears to everyone that Rama was a long-duration space craft designed to carry generations of aliens to a destination centuries away - but something, somewhere went wrong, and everyone died, and the empty dead ship just kept drifting for millions of years.

One of his crew, Boris Rodrigo, thinks that Rama is here to pick up a few million humans and take them to Heaven in space, where the alien race that Jesus represented, live. Entering through three backup airlocks, Norton finds an entire hollowed out environment inside Rama.

On the inside, Rama is completely dark. Using flares launched down the center line of the cylinder, they see that Rama has domed caps at both ends, massive city-like structures on the inside walls, and a body of (frozen) water that forms a ring around the middle, which they call the Cylindrical Sea. There are massive city-like structures on the inner walls of the cylinder and a city on an island in the middle of the Cylindrical Sea. They call the island city New York; the others are called Rome, Paris, Peking, Moscow, London, and Tokyo.

The geography of Rama is mapped in the dark. There are two domes or bowls at either end. The Northern bowl where the airlocks are has three equally spaced stairways that lead outward/downward to the inner floor. The Southern bowl has complex buttressed spikes pointing toward the opposite end of Rama. Between them is the Central Plain, divided by the Cylindrical Sea into Northern and Southern continents.

They establish a base camp, using the long staircases which take hours to climb. At the bottom breathable air remains. In the pitch dark, Rama appears dead, and the Rama Committee thinks it may be a derelict, that ran out of power or supplies a million years ago. Norton and a team hike out to explore "Paris," the nearest city, and find that it is more like a sealed complex with seamless edges. They find immense long trenches that appeared to be filled with ice but were instead solid mystery material, and finally they reach the shore of the Cylindrical Sea which appeared to be filled with ice, and actually was filled with ice. The water ice they sample is full of complex carbon molecules and metal salts.

Still approaching the Sun rapidly, Rama warms up from the outside to the inside. Temperature changes bring the possibility of sudden hurricane-force winds as heat rises from the walls of Rama to the center. As the crew temporarily evacuates up the long staircases, the trenches - thought to be reservoirs - suddenly illuminate, proving to be massive interior lighting panels - three on each continent.

The Ambassador from Mercury addresses the Rama Committee. They are very concerned. Far from being a dead derelict, it seems the systems are still running on Rama. Mercury colony points out that of Rama were to make a course adjustment, it could dominate the Solar System from a close solar orbit near Mercury. Millions of people live under the surface of Mercury. Tensions rise between Mercury and Earth.

Meanwhile, Endeavour's crew re-enters Rama after the hurricane season is over. As they do so, they find that the air is now thick with oxygen and water vapor, and oxygen-producing alien microbes seem to have flourished in the Cylindrical Sea. The Sea itself has melted and only a few icebergs remain. Clouds and fog line the inside of the huge cylinder. Continuing their exploration, they use a makeshift boat to cross the waters to "New York," which also turns out to be some kind of factory, also sealed up.

Jimmy Pak, one of the crew of Endeavour, happens to be a low-gravity athlete. He reveals he has an ultralight pedal-powered aircraft on board. He volunteers to use it to explore the Southern Continent. The flimsy aircraft is soon launched with young Jimmy piloting. He flies down the center line of Rama to the opposite end, getting good videos of the Southern continent, and flying right up to the giant spike called Big Horn.

To improve stability on the return trip, Jimmy pilots down toward the wall and thicker air. Just as he starts back, Big Horn and the six Little Horns start erupting with electrical discharges, lines of plasma lightning that fill the whole southern bowl. Jimmy and his small aircraft fold up and fall toward the floor of Rama, on the far end from the airlocks and the ship.

He wakes up later to find a strange crab-like thing is chopping up his ultralight and taking it away. He is able to retrieve his water and food from the wreckage and follows the crab until it reaches a well. It dumps his broken ultralight into the water and leaves.

Jimmy heads toward the Cylindrical Sea, encountering patches of rectangular land plots - some unknown and weird, others very much like farm fields and animal pens - all sealed up in tough non-plastic material. He reaches the shores of the Sea where his friends are waiting in the boat. The shores on the Northern end were low, but the Southern edge of the Sea had cliffs 500 meters high. Jimmy risks his life and jumps into the poisonous water at 0.5 gravities, using his shirt as a parachute.

He is rescued and is sick on the way back to the Northern shore. Everyone is relieved he is alive because he was the youngest person on the ship. As they sail back across the Cylindrical Sea, the Horns light up again and discharge a huge amount of lightning. Rama shakes as it makes an attitude adjustment.

Rama rotates around its long axis, causing a tidal wave to be formed that is heading directly toward the rescue party in the boat. As they race toward shore, the wave begins to break up as it hits underwater wave breakers. The boaters drop a weighted line and discover they are right on top of a breaker. If the wave passes them here, in shallow water, it will kill them all. They are barely able to pilot the boat into deeper water before the wave hits, shaking them up but not capsizing the boat.

It's possible the Mercury colonists were right after all. Rama has altered its orientation in space, which means it could be about to change course toward the Earth. The crew in the boat continues toward the Northern shore, but are badly surprised when a giant, many-armed dead sea creature floats to the surface. It is quickly chewed to pieces by shark-like creatures.

A bit later in the human camp, there is a close encounter. A three-legged thing with a small round body walks around, looking at everything with three blue eyes, feelings things with three feathery tentacles.

The land is also soon covered with alien beings. Each seems to have a specific function. The crabs pick up debris and toss it in the water. Sharks in the water chew up the debris. The "giraffes" with two necks are like cranes, they pick things up and move them. There are big hippopotamus/bulldozers, and puffy-legged centipedes polish the giant lights. And the three-legged tall spiders just look at everything, like cameras. Without interfering, the crew is able to take a broken-legged spider back to the ship and dissect it. They turn out to be biological robots with electrical batteries instead of organs. They are made from the chemicals found in the Cylindrical Sea.

Meanwhile, Commander Norton is told over secure channel that Mercury has launched a rocket with a nuclear bomb toward Rama, as a precaution. At great risk, Boris Rodrigo goes out into space by himself toward the approaching missile to try and disarm it before it strikes. He works against time as the missile sends video of him back to Mercury at the speed of light, and against the possibility of the controllers sending a destruct command at any moment. He succeeds in disarming the missile and its guidance, and diverting it away from Rama.

With little time remaining, due to the crises, Commander Norton authorizes a trip to "London," where they use a cutting laser to enter a sealed building. It turns out to be a holographic storage room, with glass-like columns containing 3D images of hundreds of artifacts, including a three-legged, three-armed set of alien clothing. The Ramans seem to do everything in threes...

As they return to camp, Rama's lights dim, and begin to pulse. Every single robot in Rama suddenly turns, runs, and and jumps into the sea. Leaving all of their equipment the entire crew evacuates Rama and takes off.

They watch from a safe distance as the giant ship makes more course adjustments. Will it point itself toward an orbit around the Sun? Or, worse, point toward earth? Is this great vessel here.. for US???

Rama goes close to the Sun and suddenly wraps itself in a force-field like a mirror bubble. It pulls in a streamer of plasma from the Sun and changes direction towards...

The Magellanic Cloud... so far away that Rama will take another billion years to get there. It seems we had nothing to fear - our Sun was simply a refueling stop on the way out of the Galaxy toward a destination somewhere else. Whatever Rama was or is, it was probably a coincidence that humans were here when it happened by. The Solar system and the human race is safe... except of course, that the Ramans do EVERYTHING in threes...