Portal:Solar System

A close-up of 10 km (6.2 mi) high mountains within the equatorial ridgeonSaturn's moon Iapetus, photographed by the Cassini orbiter. Above the middle of the image can be seen a place where an impact has exposed the bright ice beneath the dark overlying material. The image was taken on September 10, 2007, with the Cassini spacecraft narrow-angle camera at a distance of approximately 3,870 km (2,400 mi) from Iapetus.

Hyperion, a moon of Saturn, is one of the largest highly irregular (non-spherical) bodies in the Solar System. Enhanced image processing was used to bring out details and color differences in this photo taken by the Cassini orbiter. Hyperion is entirely saturated with deep, sharp-edged craters that give it the appearance of a giant sponge. Dark material fills the bottom of each crater.

Rhea, at 1,528 kilometres (949 mi) across, is the second-largest moonofSaturn and the ninth largest moon in the Solar System. It was discovered in 1672 by Giovanni Domenico Cassini, who named it after the Titan RheaofGreek mythology, "mother of the gods".

The giant Tirawa impact basin is seen above and to the right of center. Tirawa, and another basin to its southwest, are both covered in impact craters, indicating they are quite ancient.

101955 Bennu is a carbonaceous asteroid discovered by the Lincoln Near-Earth Asteroid Research project in 1999. Bennu has a roughly spheroidal shape, an effective diameter of about 484 m (1,588 ft), and a rough, boulder-strewn surface. It is a potentially hazardous object, with a cumulative 1-in-2,700 chance of impacting Earth between 2175 and 2199. It is named after the Bennu, an ancient Egyptian bird deity associated with the Sun, creation, and rebirth. This mosaic image of Bennu consists of twelve PolyCam images taken by NASA's OSIRIS-REx spacecraft from a range of 24 km (15 mi). The primary goal of the mission is to collect a sample from the asteroid's surface, which is scheduled to take place on October 20, 2020, and return the sample to Earth for analysis.

Uranus is the seventh planet from the Sun and the fourth most massive in the Solar System. In this photograph from 1986 the planet appears almost featureless, but recent terrestrial observations have found seasonal changes to be occurring.

The International Space Station (ISS) is a space stationinlow Earth orbit, run as a joint project by the American, Russian, Japanese, European, and Canadian space agencies. Its first component was sent into orbit in 1998, and it has been inhabited continuously since 2000. The ISS consists of pressurised modules, external trusses, solar arrays, and other components, which have been launched by Russian Proton and Soyuz rockets, and American Space Shuttles. It serves as a microgravity and space environment research laboratory in which crew members conduct experiments in biology, human biology, physics, astronomy, meteorology, and other fields.

This photograph, taken in 2011 by Italian astronaut Paolo Nespoli from a departing Russian Soyuz spacecraft, shows the ISS and the docked Space Shuttle Endeavour.

The Blue Marble is a famous photograph of Earth. NASA officially credits the image to the entire Apollo 17 crew — Eugene Cernan, Ronald Evans and Jack Schmitt — all of whom took photographic images during the mission. Apollo 17 passed over Africa during daylight hours and Antarctica is also illuminated. The photograph was taken approximately five hours after the spacecraft's launch, while en route to the Moon. Apollo 17, notably, was the last manned lunar mission; no humans since have been at a range where taking a "whole-Earth" photograph such as "The Blue Marble" would be possible.

Tranquility Base is the landing site of the Apollo 11 mission on the Moon where, on July 20, 1969, humans first landed and walked on a celestial body other than the Earth. This photograph was taken at Tranquility Base by Neil Armstrong, the Apollo 11 commander, and depicts crewmember Buzz Aldrin with scientific equipment he had just deployed on the lunar surface. In the background on the right of the image is the lunar module, Eagle; the United States flag planted at the site during the mission was blown over the next day by the exhaust of the ascent rocket.

The Sun is the star at the center of the Solar System. It is a nearly perfect sphere of hot plasma, heated to incandescencebynuclear-fusion reactions in its core, radiating the energy mainly as visible light and infrared radiation. It is by far the most important source of energy for life on Earth. Its diameter is about 1.39 million kilometres (860,000 mi), or 109 times that of Earth. Its mass is about 330,000 times that of Earth, and accounts for about 99.86 percent of the total mass of the Solar System. Roughly three-quarters of the Sun's mass consists of hydrogen; the rest is mostly helium, with much smaller quantities of heavier elements, including oxygen, carbon, neon, and iron. This diagram illustrates the general structure of the Sun, with all features drawn to scale.

Mercury is the smallest and closest to the Sun of the eight planets in the Solar System. It has no known natural satellites. The planet is named after the Roman deity Mercury, the messenger to the gods.

Mars is the fourth planet from the Sun and is known as the "Red Planet" due to its reddish appearance as seen from Earth. The planet is named after Mars, the Roman god of war. A terrestrial planet, Mars has a thin atmosphere and surface features reminiscent both of the impact craters of the Moon and the volcanoes, valleys, deserts and polar ice caps of the Earth. The planet has the highest mountain in the Solar System, Olympus Mons, as well as the largest canyon, Valles Marineris. Mars's rotation period and seasonal cycles are also similar to those of the Earth. Of all the planets in the Solar System other than Earth, Mars is the most likely to harbour liquid water and perhaps life. There are ongoing investigations assessing Mars's past potential for habitability, as well as the possibility of extant life. Future astrobiology missions are planned, including NASA's Mars 2020 rover and the European Space Agency (ESA)'s Rosalind Franklin rover. In November 2016, NASA reported finding a large amount of underground ice in the Utopia Planitia region of the planet. The volume of water detected has been estimated to be equivalent to the volume of water in Lake Superior. Mars has two moons, Phobos and Deimos, which are small and irregularly shaped.

This picture is a true-colour image of Mars, taken from a distance of about 240,000 kilometres (150,000 mi) by the OSIRIS instrument on ESA's Rosetta spacecraft, during its February 2007 flyby of the planet. The image was generated using OSIRIS's orange (red), green and blue filters.

The Moon is the only natural satelliteofEarth and the fifth largest moon in the Solar System. Owing to its synchronous rotation around Earth, the Moon always shows essentially the same face: its near side, which is marked by dark volcanic maria, as well as the bright ancient crustal highlands and the prominent impact craters. However, variations in the Moon's orbital speed due to its orbital eccentricity cause a libration of several degrees of longitude; the alignment of the Moon's orbital plane causes a similar libration in latitude. The Moon was first reached in September 1959 by the Soviet Union's unmanned Luna 2, followed by the first successful soft landing by Luna 9 in 1966. The United States Apollo program achieved the only manned lunar missions to date, including Apollo 8 in 1968, the first manned orbital mission, as well as Apollo 11, the first of six manned landings between 1969 and 1972.

This picture shows the near side of the Moon close to its greatest northern ecliptic latitude, so the southern craters are especially prominent. Tranquility Base, Apollo 11's landing site, is located near the mid-right in the photograph.

Phobos, the larger and closer of the two moonsofMars, as seen from about 6,000 kilometres (3,700 mi) away. A small, irregularly shaped object, Phobos orbits about 9,377 km (5,827 mi) from the center of Mars, closer to its primary than any other planetary moon. The illuminated part of Phobos seen in the images is about 21 km (13 mi) across. The most prominent feature in the images is the large crater Stickney in the lower right. With a diameter of 9 km (5.6 mi), it is the largest feature on Phobos.

The Sun is the star at the center of the Solar System. It is a nearly perfect sphere of plasma, heated by nuclear fusionofhydrogen into helium in its core, with internal convective motion that generates a magnetic field via a dynamo process. It is by far the most important source of energy for life on Earth. Its diameter is about 1.39 million kilometres (860,000 miles) or 109 times that of Earth, while its mass is about 330,000 times that of Earth. It accounts for about 99.86% of the total mass of the Solar System. Roughly three-quarters of the Sun's mass consists of hydrogen; the rest is mostly helium, with much smaller quantities of heavier elements, including oxygen, carbon, neon and iron.

This false-color photograph of the Sun was taken by the Atmospheric Imaging Assembly instrument on NASA's Solar Dynamics Observatory (SDO) at a wavelength of 304 angstroms, in the extreme ultraviolet region of the electromagnetic spectrum.

Comet C/2006 P1 (McNaught), as seen from Swifts Creek, Victoria, Australia. This non-periodic comet, the brightest in over 40 years, was discovered on August 7, 2006 by British-Australian astronomer Robert H. McNaught. It was first visible in the northern hemisphere, reaching perihelion on January 12, 2007 at a distance of 0.17 AU.