A significantly large asteroid, or small moon/planetoid, was embedded in the underside of the city-sized JMC mining spaceship Red Dwarf, and was one of its most prominent external features. The asteroid was already present before Red Dwarf left Earth's solar system, and was still embedded in the underside of the ship three million years later.
In later series, after the ship was recreated by the nanobots, two asteroids were embedded in the underside of the ship.
Rob Grant has stated that the miners aboard the ship mined the asteroid as the ship went along, giving the ship continual source of ore during interplanetary travel and when not mining a planetoid. However, how the asteroid came to be there is unclear.
Since it was a mining ship, it is likely that the inclusion of the asteroid into Red Dwarf was not a result of meteor impacts, but was deliberate and intentional on the part of the JMC. This would have given the crew a continual source of ore to mine from within the ship as they went on their rounds around the solar system. This appears more so in the remastered version of the ship, and also in the nanobot-upgraded ship of Series VIII, where it seems as though the ship had been constructed around two separate asteroids or that space had been made in the ships design to take in, mine and then discard such asteroids.
In the early television series, the model of the ship made it appear as though the inclusion of the asteroid was fairly jagged. From Series X onward, Red Dwarf had altered somewhat, and had one large asteroid embedded in its underside with several small asteroids around it. The hull of the ship surrounding the large and small asteroids shows clear signs of impact damage implying the presence of these rocks in the ships structure was from an accidental impact.
In original concept illustrations of Red Dwarf (see for example "Bodysnatcher"), the asteroid was much larger and more prominent, to the point that it appeared as though the ship was actually constructed around it.
In the novel Infinity Welcomes Careful Drivers, the asteroid is described as a small moon which was ripped from its orbit by the gravitational pull of the massive Red Dwarf.
- Early concept artwork for Red Dwarf (some of which can be seen in reconstructed episodes such as "Bodysnatcher" and "Dad") show that the two asteroids were originally to have been much bigger before the model was built, with the ship itself shaped by the contours of the asteroids. This would suggest that the asteroids had been there from the ship's construction. When the model was built it retained the asteroids, but toned them down in size and prominence somewhat.
- Prop maker Peter Wragg, who designed the model for Red Dwarf, said in an interview that the asteroids were a deliberate design choice to make the ship appear much older and more traveled. They were meteorites which had embedded themselves into the ship, and the ship owners had merely decided to leave them there.
- There is further evidence from later series that the asteroids were not deliberately embedded in the ship, but the result of an unforeseen collision. The behind-the-scenes production documentary on the Series X DVD, "We're Smegged", shows clear impact damage and jagged edges on the part of the model underneath the asteroids. Also, a monitor readout seen in the background during Series XI reads "small meteoroid jammed in hull" in red under the hull integrity section.