The Mariner program was conducted by the American space agency NASA to explore other planets. Between 1962 and late 1973, NASA's Jet Propulsion Laboratory (JPL) designed and built 10 robotic interplanetary probes named Mariner to explore the inner Solar System - visiting the planets Venus, Mars and Mercury for the first time, and returning to Venus and Mars for additional close observations.
Space exploration is the use of astronomy and space technology to explore outer space. While the exploration of space is currently carried out mainly by astronomers with telescopes, its physical exploration is conducted both by uncrewed robotic space probes and human spaceflight. Space exploration, like its classical form astronomy, is one of the main sources for space science.
Voyager 2 is a space probe launched by NASA on August 20, 1977, to study the outer planets and interstellar space beyond the Sun's heliosphere. As a part of the Voyager program, it was launched 16 days before its twin, Voyager 1, on a trajectory that took longer to reach gas giants Jupiter and Saturn but enabled further encounters with ice giants Uranus and Neptune. Voyager 2 remains the only spacecraft to have visited either of the ice giant planets, and was the third of five spacecraft to achieve Solar escape velocity, which will allow it to leave the Solar System.
Mariner 10 was an American robotic space probe launched by NASA on 3 November 1973, to fly by the planets Mercury and Venus. It was the first spacecraft to perform flybys of multiple planets.
A gravity assist, gravity assist maneuver, swing-by, or generally a gravitational slingshot in orbital mechanics, is a type of spaceflight flyby which makes use of the relative movement and gravity of a planet or other astronomical object to alter the path and speed of a spacecraft, typically to save propellant and reduce expense.
MESSENGER was a NASA robotic space probe that orbited the planet Mercury between 2011 and 2015, studying Mercury's chemical composition, geology, and magnetic field. The name is a backronym for "Mercury Surface, Space Environment, Geochemistry, and Ranging", and a reference to the messenger god Mercury from Roman mythology.
In astronomy, an extraterrestrial sky is a view of outer space from the surface of an astronomical body other than Earth.
Pale Blue Dot is a photograph of Earth taken on February 14, 1990, by the Voyager 1 space probe from an unprecedented distance of approximately 6 billion kilometers, as part of that day's Family Portrait series of images of the Solar System.
The Lunar and Planetary Laboratory (LPL) is a research center for planetary science located in Tucson, Arizona. It is also a graduate school, constituting the Department of Planetary Sciences at the University of Arizona. LPL is one of the world's largest programs dedicated exclusively to planetary science in a university setting. The Lunar and Planetary Lab collection is held at the University of Arizona Special Collections Library.
An extraterrestrial vortex is a vortex that occurs on planets and natural satellites other than Earth that have sufficient atmospheres. Most observed extraterrestrial vortices have been seen in large cyclones, or anticyclones. However, occasional dust storms have been known to produce vortices on Mars and Titan. Various spacecraft missions have recorded evidence of past and present extraterrestrial vortices. The largest extraterrestrial vortices are found on the gas giants, Jupiter and Saturn, and the ice giants, Uranus and Neptune.
The Family Portrait, or sometimes Portrait of the Planets, is an image of the Solar System acquired by Voyager 1 on February 14, 1990, from a distance of approximately 6 billion km from Earth. It features individual frames of six planets and a partial background indicating their relative positions. The picture is a mosaic of 60 frames. The frames used to compose the image were the last photographs taken by either Voyager spacecraft. The frames were also the source of the famous Pale Blue Dot image of the Earth. Astronomer Carl Sagan, who was part of the Voyager imaging team, campaigned for many years to have the pictures taken.
The exploration of Uranus has, to date, been through telescopes and a lone probe by NASA's Voyager 2 spacecraft, which made its closest approach to Uranus on January 24, 1986. Voyager 2 discovered 10 moons, studied the planet's cold atmosphere, and examined its ring system, discovering two new rings. It also imaged Uranus' five large moons, revealing that their surfaces are covered with impact craters and canyons.
The exploration of Saturn has been solely performed by crewless probes. Three missions were flybys, which formed an extended foundation of knowledge about the system. The Cassini–Huygens spacecraft, launched in 1997, was in orbit from 2004 to 2017.
Neptune has been directly explored by one space probe, Voyager 2, in 1989. As of 2024, there are no confirmed future missions to visit the Neptunian system, although a tentative Chinese mission has been planned for launch in 2024. NASA, ESA, and independent academic groups have proposed future scientific missions to visit Neptune. Some mission plans are still active, while others have been abandoned or put on hold.
Discovery and exploration of the Solar System is observation, visitation, and increase in knowledge and understanding of Earth's "cosmic neighborhood". This includes the Sun, Earth and the Moon, the major planets Mercury, Venus, Mars, Jupiter, Saturn, Uranus, and Neptune, their satellites, as well as smaller bodies including comets, asteroids, and dust.
The following outline is provided as an overview of and topical guide to the Solar System:
The Day the Earth Smiled is a composite photograph taken by the NASA spacecraft Cassini on July 19, 2013. During an eclipse of the Sun, the spacecraft turned to image Saturn and most of its visible ring system, as well as Earth and the Moon as distant pale dots. The spacecraft had twice taken similar photographs in its previous nine years in orbit around the planet. The name also refers to the activities associated with the event, as well as to the photographic mosaic created from it.
