Search results
Results From The WOW.Com Content Network
Satellite galaxies that orbit from 1,000 ly (310 pc) of the edge of the disc of the Milky Way Galaxy to the edge of the dark matter halo of the Milky Way at 980,000 ly (300 kpc) from the center of the galaxy, [ a ] are generally depleted in hydrogen gas compared to those that orbit more distantly. This is because of their interactions with the ...
List of nearest galaxies. This is a list of known galaxies within 3.8 megaparsecs (12.4 million light-years) of the Solar System, in ascending order of heliocentric distance, or the distance to the Sun. This encompasses about 50 major Local Group galaxies, and some that are members of neighboring galaxy groups, the M81 Group and the Centaurus A ...
Explorer 1 was the first satellite launched by the United States in 1958 and was part of the U.S. participation in the International Geophysical Year (IGY). The mission followed the first two satellites, both launched by the Soviet Union during the previous year, Sputnik 1 and Sputnik 2. This began a Space Race during the Cold War between the ...
List of USA satellites. This is a list of satellites and spacecraft which have been given USA designations by the United States Air Force. These designations have been applied to most United States military satellites since 1984, and replaced the earlier OPS designation. As of June 2022, USA designations have been assigned to 331 space satellites.
The Solar System was assumed to be near the center. Proof of the Milky Way consisting of many stars came in 1610 when Galileo Galilei used a telescope to study the Milky Way and discovered that it is composed of a huge number of faint stars. Galileo also concluded that the appearance of the Milky Way was due to refraction of the Earth's atmosphere.
Barring an incident, Pioneer 11 will pass near one of the stars in the constellation in about 4 million years. [3] Voyager 2 – launched in August 1977, flew past Jupiter in 1979, Saturn in 1981, Uranus in 1986, and Neptune in 1989. The probe left the heliosphere for interstellar space at 119 AU on November 5, 2018. [4] Voyager 2 is still active.
Explorers Program. An Explorer mission observes Sagittarius A*, the Milky Way's central black hole, flaring. The Explorers program [1] is a NASA exploration program that provides flight opportunities for physics, geophysics, heliophysics, and astrophysics investigations from space. Launched in 1958, Explorer 1 was the first spacecraft of the ...
A satellite galaxy is a smaller companion galaxy that travels on bound orbits within the gravitational potential of a more massive and luminous host galaxy (also known as the primary galaxy). [1] Satellite galaxies and their constituents are bound to their host galaxy, in the same way that planets within our own solar system are gravitationally ...