// ORBITAL LOGISTICS AND PROPULSION TERM
Parallax
Parallax is the apparent shift in an object's position when viewed from different angles, like how your thumb seems to move if you close one eye then the other.
TECHNICAL DEFINITION
Parallax is the apparent displacement or difference in the apparent position of an object viewed along two different lines of sight, used in astronomy to measure distances to stars and other celestial objects via triangulation.
BACKGROUND
Outer space, or simply space, is the expanse that exists beyond Earth's atmosphere and between celestial bodies. It contains ultra-low levels of particle densities, constituting a near-perfect vacuum of predominantly hydrogen and helium plasma, permeated by electromagnetic radiation, cosmic rays, neutrinos, magnetic fields and dust. The baseline temperature of outer space, as set by the background radiation from the Big Bang, is 2.7 kelvins.
READ MORE ON WIKIPEDIASYNONYMS & ALIASES
- Stellar parallax
- trigonometric parallax
- apparent shift
USAGE NOTE
Astronomers use stellar parallax to determine the distances to nearby stars, a fundamental step in building the cosmic distance ladder.
DEVELOPERS
Organizations developing technology related to Parallax.
ESA's Gaia mission is specifically designed to map the Milky Way galaxy with unprecedented precision, using stellar parallax to determine the distances, motions, and luminosities of billions of stars.
NASA conducts numerous missions and research initiatives that leverage parallax, from measuring distances to celestial objects with telescopes like Hubble and the upcoming Roman Space Telescope, to creating 3D maps of planetary surfaces using stereo imaging from orbiters.
Maxar is a leading provider of Earth intelligence and space infrastructure. They utilize satellite imagery, including stereo pairs, to create highly accurate 3D models and digital elevation models of Earth's surface, relying on parallax principles for depth perception.
Operating the largest fleet of Earth observation satellites, Planet Labs provides daily imagery of the entire Earth. They use their extensive data to generate 3D products and digital terrain models, which are derived using parallax from multiple satellite passes and observations.
Airbus Defence and Space develops and manufactures a wide range of satellites, including Earth observation missions that employ stereo cameras and processing techniques to generate 3D topographical data using parallax for applications in mapping and surveying.
JAXA contributes to astronomical observation and planetary science. Their missions often involve techniques like stellar parallax for measuring cosmic distances and stereo imaging for detailed topographical mapping of planetary bodies.
Ball Aerospace designs and manufactures advanced scientific instruments and spacecraft components. They are involved in building sensors and optical systems for Earth observation, astrophysics, and planetary missions where parallax-based measurements are critical for data collection.
Lockheed Martin develops and integrates various space systems, including scientific and Earth observation satellites. Their work involves advanced imaging and sensing technologies that often apply principles of parallax for creating 3D terrain maps and precise positioning in space.