70 Ophiuchi a binary star system located 16.6 light years away from the Earth. It is in the constellation Ophiuchus. At magnitude 4 it is a typical less bright star usually visible to the unaided eye away from city lights.
The primary star is a yellow-orange main sequence dwarf BY Draconis variable of spectral type K0, and the secondary star is an orange main sequence dwarf of spectral type K4. The two stars orbit each other at an average distance of 23.2 AUs. But since the orbit is highly elliptical (at e=0.499), the separation between the two varies from 11.4 to 34.8 AUs, with one orbit taking 83.38 years to complete.
In Space Opera
- Dune (1965) and other novels in the Dune universe by Frank Herbert. Sikun is the third planet from 70 Ophiuchi.
- "Miri" (1966), episode of Star Trek: The Original Series? written by Adrian Spies?, as part of the film, television, and print franchise originated by Gene Roddenberry?. In the James Blish? treatment of this episode, the events take place on a planet in the 70 Ophiuchi star system. This planet is an exact duplicate of the Earth in every detail.
- Starforce: Alpha Centauri? (1974), science fiction board game published by Simulation Publications based on a concept by Redmond Simonsen. In this game as well as in the spin-off game StarSoldier, 70 Ophiuchi is the home of the Rame?, an advanced, space-faring race.
- Frontier: Elite II? (1993) and Frontier: First Encounters? (1995), computer games written by David Braben? et al. The 70 Ophiuchi system has an economy based on mining and heavy industry, which makes its population (in the hundreds of thousands) uncharacteristically large.