"Plutonians dead, the danger to the solar system is past. Burl sees then the people of other planets and of other stars coming together in peace and mutual understanding. The book was reviewed by “When the power of the sun becomes noticeably diminished, young Burl Denning and his expedition take off in an anti-gravitational ship to discover the cause and its location. After a dizzying tour of all the planets, they realize that the trouble springs from Pluto, a belligerent planet which is trying to usurp the life-giving power which the sun gives earth. Making an alliance with the friendly"
"Neptune Neptune is the eighth and farthest known planet from the Sun in the Solar System. In the Solar System, it is the fourth-largest planet by diameter, the third-most-massive planet, and the densest giant planet. Neptune is 17 times the mass of Earth and is slightly more massive than its near-twin Uranus, which is 15 times the mass of Earth and slightly larger than Neptune. Neptune orbits the Sun once every 164.8 years at an average distance of . It is named after the Roman god of the sea and has the astronomical symbol ♆, a stylised version of the"
"Proxima Centauri b Proxima Centauri b (also called Proxima b or Alpha Centauri Cb) is an exoplanet orbiting in the habitable zone of the red dwarf star Proxima Centauri, which is the closest star to the Sun and part of a triple star system. It is located about 4.2 light-years (1.3 parsecs, 40 trillion km, or 25 trillion miles) from Earth in the constellation of Centaurus, making it the closest known exoplanet to the Solar System. Proxima Centauri b orbits the star at a distance of roughly with an orbital period of approximately 11.2 Earth days, and has an estimated"
"Wisp or Light Sail type concepts). Such a system could grow organically if space-based solar power became a significant component of Earth's energy mix. Consumer demand for a multi-terawatt system would automatically create the necessary multi-million ton/year logistical system. Distances between the planets in the Solar System are often measured in astronomical units (AU), defined as the average distance between the Sun and Earth, some . Venus, the closest other planet to Earth is (at closest approach) 0.28 AU away. Neptune, the farthest planet from the Sun, is 29.8 AU away. As of January 2018, Voyager 1, the farthest man-made"
"Venus for the seventh and last time, decreasing its period to 88 or 89 days and allowing it to approach closer to the Sun. The perihelion distances above are from the center of the Sun. For altitude above the surface, subtract one solar radius ≈ 0.7 Gm.<br> By way of comparison, the planet Mercury orbits the Sun at a distance varying from about 46.0 Gm (46,001,200 km) at its closest to about 69.8 Gm (69,816,900 km) at its farthest. Parker Solar Probe Parker Solar Probe (previously Solar Probe, Solar Probe Plus, or Solar Probe+, abbreviated PSP) is a NASA robotic"
"2018 VG18 , nicknamed ""Farout"", is a distant trans-Neptunian object. At an observed distance of ~ (more than three times the average distance of Pluto from the Sun, and nearly twice the average distance of Eris), as of December 2018 it is the most distant object in the Solar System ever observed (displacing the previous record holder, Eris, at 96 AU), and the first object discovered beyond , hence the nickname. However, it is not close to being the object with the most distant orbit on average, as its semi-major axis is only estimated to be about 95.2 AU (in"
"of the distance from the Earth to the Sun. Comparatively, Mercury, the closest planet to the Sun, has a semi-major axis distance of 0.39 AU. Proxima Centauri b receives about 65% of the amount of radiative flux from its host star that the Earth receives from the Sun - for comparison Mars receives about 43%. Most of the radiative flux from Proxima Centauri is in the infrared spectrum. In the visible spectrum the exoplanet receives only ~3% of the PAR (400-700 nm) of Earth irradiance - for comparison Jupiter receives 3.7% and Saturn 1.1%. So it would usually not get"
"that between Saturn and the Sun (11.2 AU). Alpha Centauri C, or Proxima Centauri, is a small and faint red dwarf (Class M). Though not visible to the naked eye, Proxima Centauri is the closest star to the Sun at a distance of , being slightly closer than Alpha Centauri AB at a distance of . Currently, the distance between Proxima Centauri and Alpha Centauri AB is about , equivalent to about 430 times the radius of Neptune's orbit. Proxima Centauri b is an Earth-sized exoplanet in the habitable zone of Proxima Centauri; it was discovered in 2016. ""α Centauri"""
"Extragalactic planet An extragalactic planet, also known as an extragalactic exoplanet, is a star-bound planet, or rogue planet, located outside of the Milky Way galaxy. Due to the huge distances to such worlds, they would be very hard to detect directly. However, indirect evidence suggests that such planets may exist. Nonetheless, the most distant known planets are SWEEPS-11 and SWEEPS-04, located in Sagittarius, approximately 27,710 light-years from the Sun, while the Milky Way is between 100,000–180,000 light years in diameter. This means that even galactic planets located further than that distance have not been detected. A planet with a mass"
"to as ""volatiles"". The distance from Earth to the Sun is . For comparison, the radius of the Sun is . Thus, the Sun occupies 0.00001% (10 %) of the volume of a sphere with a radius the size of Earth's orbit, whereas Earth's volume is roughly one millionth (10) that of the Sun. Jupiter, the largest planet, is from the Sun and has a radius of , whereas the most distant planet, Neptune, is from the Sun. With a few exceptions, the farther a planet or belt is from the Sun, the larger the distance between its orbit and"
"given minimum mass. The planet has one of the longest orbits currently known for an extrasolar planet. The planet's mean distance from the star is close to the distance between Jupiter and the Sun. However, unlike Jupiter it has an eccentric orbit. At periastron the distance between the planet and the star is only 2.51 AU and at apastron the distance is as much as 5.33 AU (compared to the Solar System, distance from the Sun to the inner asteroid belt and from Sun to just beyond the orbit of Jupiter). The signal produced by the planet is very weak"
"Kepler-20f Kepler-20f (also known by its Kepler Object of Interest designation ""KOI-70.05"") is an exoplanet orbiting the Sun-like star Kepler-20, the second outermost of five such planets discovered by NASA's ""Kepler"" spacecraft. It is located approximately 929 light-years (285 parsecs, or about km) from Earth in the constellation Lyra. The exoplanet was found by using the transit method, in which the dimming effect that a planet causes as it crosses in front of its star is measured. The planet is notable as it has the closest radius to Earth known so far. Kepler-20f is very likely (>95% chance) a rocky"
"0.995 AU (or 700,000 km) closer to the star than Earth to the Sun, but its orbital eccentricity is much higher compared to Earth. At periastron, the planet’s closest distance to the star is 0.708 AU, which is slightly closer to the star than Venus to the Sun. At apastron, the planet’s farthest distance to the star is 1.283 AU, which is more than halfway between the orbits of Earth and Mars. 30 Arietis Bb 30 Arietis Bb (sometimes abbreviated 30 Ari Bb) is an extrasolar planet which orbits the F-type main sequence star 30 Arietis B, located in a"
"and ""New Horizons"". The one farthest from the Sun is ""Voyager 1"", which is more than 100 AU distant and is moving at 3.6 AU per year. In comparison, Proxima Centauri, the closest star other than the Sun, is 267,000 AU distant. It will take ""Voyager 1"" over 74,000 years to reach this distance. Vehicle designs using other techniques, such as nuclear pulse propulsion are likely to be able to reach the nearest star significantly faster. Another possibility that could allow for human interstellar spaceflight is to make use of time dilation, as this would make it possible for passengers"
"moon Triton to be investigated around 2029. The proposed ""New Horizons 2"" mission (which was later scrapped) might also have done a close flyby of the Neptunian system. Neptune Neptune is the eighth and farthest known planet from the Sun in the Solar System. In the Solar System, it is the fourth-largest planet by diameter, the third-most-massive planet, and the densest giant planet. Neptune is 17 times the mass of Earth and is slightly more massive than its near-twin Uranus, which is 15 times the mass of Earth and slightly larger than Neptune. Neptune orbits the Sun once every 164.8"
"are gravitationally bound to the star. Almost all of the planets detected so far are within the Milky Way. Nonetheless, evidence suggests that extragalactic planets, exoplanets further away in galaxies beyond the local Milky Way galaxy, may exist. The nearest exoplanet is Proxima Centauri b, located 4.2 light-years (1.3 parsecs) from Earth and orbiting Proxima Centauri, the closest star to the Sun. The discovery of exoplanets has intensified interest in the search for extraterrestrial life. There is special interest in planets that orbit in a star's habitable zone, where it is possible for liquid water, a prerequisite for life on"
"out to be one of the reddest objects in the Kuiper belt, comparable only to Quaoar, so the nickname was dropped. came to perihelion of 33 AUs around 1857. it is located 87.9 AUs from the Sun and moving away from the Sun at . This makes it the fifth-farthest known large body in the Solar System, after Eris (96.3 AU), V774104 (<96 AU?), (91.4 AU), (89.2 AU), and farther out than (85.7 AU) as of 4 February 2017. It has been farther from the Sun than Sedna since 2013. will be farther than both Sedna and Eris by 2045,"
"Neso (moon) Neso ( ; Greek: ""Νησώ""), also known as Neptune XIII, is the outermost known natural satellite of Neptune. It is an irregular moon discovered by Matthew J. Holman, Brett J. Gladman, ""et al."" on August 14, 2002, though it went unnoticed until 2003. Neso orbits Neptune at a distance of more than 48 Gm (million km), making it (as of 2015) the most distant known moon of any planet. At apocenter, the satellite is more than 72 Gm from Neptune. This distance is great enough to exceed Mercury's aphelion, which is approximately 70 Gm from the Sun. Neso"
"Pegasi, taking only 1.8 days or 43 hours to orbit the star. SWEEPS-11 SWEEPS-11 is an extrasolar planet orbiting the star SWEEPS J175902.67−291153.5 in the constellation Sagittarius, approximately 27,710 light years away from the Solar System (based on a distance modulus of 14.1), making it (along with SWEEPS-04) the most distant exoplanet(s) known. This planet was found in 2006 by the Sagittarius Window Eclipsing Extrasolar Planet Search (SWEEPS) program that uses the transit method. This hot Jupiter has a mass 9.7 times that of Jupiter and a radius of 1.13 times that of Jupiter. The planet orbits at about 1.75"
"average distance of 8,200,000 km (0.055 AU) from the parent star, taking 4.2 days to revolve around it. SWEEPS-04 SWEEPS-04 is an extrasolar planet orbiting the star SWEEPS J175853.92−291120.6 in the constellation Sagittarius approximately 27,710 light years away (based on a distance modulus of 14.1) from the Solar System, making it (along with SWEEPS-11) the most distant exoplanet(s) known. This planet was found in 2006 by the Sagittarius Window Eclipsing Extrasolar Planet Search (SWEEPS) program that uses the transit method. The upper limit on the planet's mass is 3.8 times the mass of Jupiter. The best fit radius is 0.81"
"close as to the Sun at its perihelion and take it as far away as at its aphelion. The aphelion, or farthest point from the Sun, would be in the general direction of the constellation of Taurus, whereas the perihelion, the nearest point to the Sun, would be in the general direction of the southerly areas of Serpens (Caput), Ophiuchus, and Libra. Brown thinks that if Planet Nine is confirmed to exist, a probe could fly by it in as little as 20 years with a powered slingshot around the Sun. The planet is estimated to have 10 times the"
"evaluated for slowly moving objects. Hundreds of TNOs were found, with diameters in the range of 50 to 2,500 kilometers. Eris, the most massive TNO, was discovered in 2005, revisiting a long-running dispute within the scientific community over the classification of large TNOs, and whether objects like Pluto can be considered planets. Pluto and Eris were eventually classified as dwarf planets by the International Astronomical Union. On Monday, December 17, 2018 the discovery of 2018 VG18, nicknamed “Farout”, was announced. Farout is the most distant solar system object so-far observed and is about 120 AU away from the sun, likely"
"of its orbit, it is even farther from the Sun than at present, with its aphelion estimated at 937 AU (31 times Neptune's distance), making it one of the most distant-known objects in the Solar System other than long-period comets. Sedna has an exceptionally long and elongated orbit, taking approximately 11,400 years to complete and a distant point of closest approach to the Sun at 76 AU. These facts have led to much speculation about its origin. The Minor Planet Center currently places Sedna in the scattered disc, a group of objects sent into highly elongated orbits by the gravitational"
"SWEEPS-11 SWEEPS-11 is an extrasolar planet orbiting the star SWEEPS J175902.67−291153.5 in the constellation Sagittarius, approximately 27,710 light years away from the Solar System (based on a distance modulus of 14.1), making it (along with SWEEPS-04) the most distant exoplanet(s) known. This planet was found in 2006 by the Sagittarius Window Eclipsing Extrasolar Planet Search (SWEEPS) program that uses the transit method. This hot Jupiter has a mass 9.7 times that of Jupiter and a radius of 1.13 times that of Jupiter. The planet orbits at about 1.75 times closer to the star than 51 Pegasi b is to 51"
"It is by far the most distant and eccentric known asteroid orbiting the Sun, varying in its distance from the Sun over its orbit by 99.89% from slightly within the orbit of Jupiter, to more than 7,000 times Earth's distance to the Sun. While its orbit extends to the inner Oort cloud, it may not be a member of it, as it approaches very near to Saturn, implying Saturn has either captured a past Oort Cloud object onto this orbit, or it was a centaur ejected by Saturn from a much smaller orbit. However, it would be impossible to project"
"the heavens. In Hawaiian, its name is ""Hele‘ekala"", a loanword for the discoverer Herschel. In Māori, its name is ""Whērangi"". Uranus orbits the Sun once every 84 years. Its average distance from the Sun is roughly . The difference between its minimum and maximum distance from the Sun is 1.8 AU, larger than that of any other planet, though not as large as that of dwarf planet Pluto. The intensity of sunlight varies inversely with the square of distance, and so on Uranus (at about 20 times the distance from the Sun compared to Earth) it is about 1/400 the"
"Distant minor planet A distant minor planet, or ""distant object"", is any minor planet found beyond Jupiter in the outer Solar System that is not commonly thought of as an ""asteroid"". The umbrella term is used by IAU's Minor Planet Center (MPC), which is responsible for the identification, designation and orbit computation of these objects. , the MPC maintains 3497 distant objects in its data base. Most distant minor planets are trans-Neptunian objects and centaurs, while relatively few are damocloids, Neptune trojans or Uranus trojans. All distant objects have a semi-major axis (average distance from the Sun) greater than 6"
"OGLE-2014-BLG-0124Lb OGLE-2014-BLG-0124Lb is one of the farthest planets that we know of today. It is approximately 13,000 light years away, located near the center of the galaxy. The planet was discovered using a technique called microlensing. In this case it took 150 days. Two telescopes are used to detect the planet and the time difference between identification by each telescope is used to calculate the distance to the planet. This also contributes to determining the mass of the planet which is about half of Jupiter's. The planet orbits a star with a mass of 0.7 solar masses and is 3.1"
"may be orbiting Sun-like stars. The nearest such planet may be 12 light-years away. Scientific findings since the 1990s have greatly influenced the scope of the fields of astrobiology, models of planetary habitability and the search for extraterrestrial intelligence (SETI). NASA and the SETI Institute have proposed categorising the increasing number of planets found using a measure called the Earth Similarity Index (ESI) based on mass, radius and temperature. According to this measure, as of 23 July 2015, the confirmed planet currently thought to be most similar to Earth on mass, radius and temperature is Kepler-438b. Scientists estimate that there"
"approach to the Sun) is estimated to have occurred around September 2010. Aphelion (furthest distance from the Sun) is estimated to have occurred around February 2016. , the asteroid is estimated to be from Earth. Perihelion (closest approach to the Sun) may not occur again until August 2021. Orbits computed with only a handful of observations can be unreliable. Short observation arcs can result in computer generated orbits rejecting some data unnecessarily. The 2018 JPL orbit determination shows a semi-major axis of 4.9 AU (albeit with a large 20 AU uncertainty) which would be near Jupiter's orbit. Such an orbit"
"Sun is younger and hotter, with an age of 4.6 billion years and an effective temperature of 5778 K. Kepler-10 is located at a distance of 173 (± 27) parsecs from the Earth, which equates to approximately 564 light years. Also, Kepler-10's apparent magnitude, or brightness as seen from Earth, is 10.96; it therefore cannot be seen with the naked eye. Per the usual exoplanet nomenclature, the first planet discovered to be orbiting Kepler-10 is called Kepler-10b. Announced in 2011, it was the first rocky planet identified outside the Solar system. The planet has a mass that is 3.33±0.49 times"
"object from Earth, is 141.5 AU away. The closest known star, Proxima Centauri, is approximately away, or over 9,000 times farther away than Neptune. Because of this, distances between stars are usually expressed in light-years, defined as the distance that a light photon travels in a year. Light in a vacuum travels around per second, so this is some or in a year. Proxima Centauri is 4.243 light-years away. Another way of understanding the vastness of interstellar distances is by scaling: One of the closest stars to the Sun, Alpha Centauri A (a Sun-like star), can be pictured by scaling"
"Proxima Centauri Proxima Centauri (), or Alpha Centauri C, is a red dwarf, a small low-mass star, about from the Sun in the constellation of Centaurus. It was discovered in 1915 by Robert Innes and is the nearest-known star to the Sun. With a quiescent apparent magnitude of 11.13, it is too faint to be seen with the naked eye. Proxima Centauri forms a third component of the Alpha Centauri system, currently with a separation of about and an orbital period of 550,000 years. At present Proxima is 2.18° to the southwest of Alpha Centauri. Because of Proxima Centauri's proximity"