Stellar Parallax | 08 Sep 2025

Source: TH

Astronomers have demonstrated a pioneering technique using stellar parallax to navigate spacecraft in deep space without relying on Earth-based beacons.

• Stellar parallax: As the earth orbits the sun, a star’s position relative to other stars might seem to shift. This is because every six months, the earth is on opposite sides of the sun, providing two different viewpoints.
  • The New Horizons spacecraft observed Proxima Centauri (4.2 light-years away) and Wolf 359 (7.9 light-years away) from a distance of 7 billion km from Earth.
• Other Space Navigation Methods:
  • Stellar Astrometric Navigation: It uses stars and special relativity to estimate a spacecraft’s 3D position and velocity by measuring the angular separation between two stars.
  • Pulsar Navigation: It uses rapidly spinning neutron stars like lamps in space to guide the way.
• NASA launched New Horizons in 2006 to study the dwarf planet Pluto, its moons, and objects in the Kuiper Belt, a disc of icy rocks and dust at the solar system’s outer edge.