recursal/Fanatic-Fandom huggingface dataset:
Uy Scuti

Uy Scuti is a star located 9,000 light-years away from Earth in the Constellation Scutum. It is one of the largest known stars by radius. With a maximum brightness of magnitude 8.29 and a minimum of magnitude 10.56. It has an estimated radius of 1,708 solar radii (1.188×109 kilometres; 7.94 astronomical units). If placed at the centre of the Solar System, its photosphere would at least engulf the orbit of Jupiter.

The star’s true size was calculated after a survey with the Very Large Telescope (VLT) in the Atacama Desert in Chile, conducted in 2012 to measure the parameters of three large stars in the region of the sky near the Galactic Centre. The other two stars were AH Scorpii and KW Sagittarii, also red supergiants with a luminosity over 100,000 times that of the Sun and among the biggest stars known. Following the survey, UY Scuti was named the largest known star, leaving behind VY Canis Majoris, NML Cygni and Betelgeuse, which had all previously carried the title.

A star’s size does not always correlate with its mass. In spite of its enormous size – 7 to 8 astronomical units across – UY Scuti does not even make the list of the most massive stars known. With an estimated mass between 7 and 10 solar masses, it is not even in the same ballpark as the current record holder R136a1 (315 solar masses), located in the Tarantula Nebula in the Large Magellanic Cloud. For reference, R136a1 has an estimated radius of only about 30 solar radii. In terms of mass, UY Scuti also does not come close to the famous Eta Carinae A (between 100 and 200 solar masses), the central star of the Carina Nebula, or to the Peony Star (WR 102ka, 100 solar masses), which illuminates the Peony Nebula.

The margin of error on the measurement of UY Scuti’s size is 192 solar radii, which means that there is a possibility that it may not be as large as WOH G64 (1,540 – 1,730 Solar Radii), the largest star in the Large Magellanic Cloud.  It certainly does not come close to the current record holders, Stephenson 2-18 (2,150 Solar Radii) and MY Cephei (2,061 Solar Radii). As UY Scuti belongs to the class of variable stars that vary in brightness because they vary in size, the star’s radius will probably change over time.
Iapetus

Iapetus is the third-largest natural satellite of Saturn and the eleventh-largest in the Solar System. Discoveries by the Cassini mission in 2007 revealed several unusual features, such as a massive equatorial ridge running three-quarters of the way around the moon and a distinctive colour pattern.

## Discovery

Iapetus was discovered by Giovanni Domenico Cassini, an Italian-born French astronomer, in October 1671. He had discovered it on the western side of Saturn and tried viewing it on the eastern side some months later, but was unsuccessful. This was also the case the following year, when he was again able to observe it on the western side, but not the eastern side. Cassini finally observed Iapetus on the eastern side in 1705 with the help of an improved telescope, finding it two magnitudes dimmer on that side.

Cassini correctly surmised that Iapetus has a bright hemisphere and a dark hemisphere, and that it is tidally locked, always keeping the same face towards Saturn. This means that the bright hemisphere is visible from Earth when Iapetus is on the western side of Saturn, and that the dark hemisphere is visible when Iapetus is on the eastern side. The dark hemisphere was later named Cassini Regio in his honour.

## Orbit

The orbit of Iapetus is somewhat unusual. Although it is Saturn's third-largest moon, it orbits much farther from Saturn than the next closest major moon, Titan. It has also the most inclined orbital plane of the regular satellites; only the irregular outer satellites like Phoebe have more inclined orbits. Because of this distant, inclined orbit, Iapetus is the only large moon from which the rings of Saturn would be clearly visible; from the other inner moons, the rings would be edge-on and difficult to see. The cause of this highly inclined orbit of Iapetus is unknown; however, it is not likely to have been captured. One suggestion for the cause of Iapetus's orbital inclination is an encounter between Saturn and another planet.

## Physical Characteristics

The low density of Iapetus indicates that it is mostly composed of ice, with only a small (~20%) amount of rocky materials.

Unlike most of the large moons, its overall shape is neither spherical nor ellipsoid, but has a bulging waistline and squashed poles. Its unique equatorial ridge is so high that it visibly distorts Iapetus's shape even when viewed from a distance. These features often lead it to be characterized as walnut-shaped.

Iapetus is heavily cratered, and Cassini images have revealed large impact basins, at least five of which are over 350 km (220 mi) wide. The largest, Turgis, has a diameter of 580 km (360 mi); its rim is extremely steep and includes a scarp about 15 km (9.3 mi) high. Iapetus is known to support long-runout landslides or sturzstroms, possibly supported by ice sliding.
Regulus

Regulus is a blue-white main-sequence star located 79 light-years away from Earth in the constellation Leo. It is the brightest star in the constellation and one of the brightest stars in the night sky. Regulus seems as a single point of light in the sky, but is actually a quadruple star system consisting of two pairs. The spectroscopic binary Regulus A consists of a blue-white main-sequence star and its companion, which has not yet been directly observed, but is probably a white dwarf.

Regulus is the nearest bright star to the ecliptic, located only 0.465 degrees from it. The next brightest star to the ecliptic is Wasat, with a visual magnitude of 3.53. Its proximity to the ecliptic means that Regulus is frequently occulted by the Moon. It can also be occulted by Mercury and Venus, but this only happens rarely. It was last occulted by Venus on July 7, 1959, and the next occultation, also by Venus, will not occur until October 1, 2044.

## Name

The name Regulus means “little king” or “prince” in Latin. In Ancient Greece, the star was known as Basiliskos (“little king”), while the Romans knew it as Basilica Stella. It was the Polish astronomer and mathematician Nicolaus Copernicus who translated these names into Latin as Regulus.

The name Regulus was officially approved by the International Astronomical Union’s (IAU) Working Group on Star Names (WGSN) on June 30, 2016. It formally applies only to the component Alpha Leonis A, but is informally used for the whole system.

Regulus was also known by the Arabic name *Qalb al-Asad*, the Greek name *Kardia Leontos* and Latin *Cor Leonis*, all meaning “the heart of the Lion.” In Europe, the star was known as Rex and Basiliscus.
Uranus

Uranus is the 7th planet from the Sun. It is slightly bigger than Neptune, but that's because it is less dense. Because it is less dense the gravity is weaker so less force is put on the surface making it slightly bigger. Uranus is the only planet in the Solar System that spins on its side, meaning that one half can be in the Sun for 42 Years. The last time that it experienced a normal day night cycle was in 2007. This is probably the result of an Earth sized object colliding into the surface a few billion years ago. Uranus has trace amounts of methane in its upper atmosphere, but it is unclear why it is a lighter blue than Neptune. It is considered an Ice Giant because it's made up of more ices and liquids than gases. In the image to the right it seems very featureless, but it isn't always like this. Every so often, white storms can pop up on the surface. It has had the coldest recorded temperature in the Solar System but on average is warmer than Neptune, and it is still unclear why.
Castor

Castor is a Blue/White main sequence star located 49 light-years away from Earth in the constellation Gemini. It is the second-brightest star in the constellation, after Pollux. Along with Pollux, it makes up the Head of the twins in Gemini. It is one of the brightest stars in the night sky at an apparent magnitude of 1.93. To the naked eye, it appears as a single star, but it is actually a sextuple star system. In 1970, Castor A and Castor B were separated by less than 2 arcseconds. The separation between the stars increased to about 6 arcseconds by 2017 and will continue to grow to a maximum of 6.5 arcseconds around the year 2100.

Castor was once believed to be a member of the Castor Moving Group, a group of stars that share a common origin and similar velocities. The group’s other members included Vega, Fomalhaut, Alderamin and Zubenelgenubi. The existence of the group was originally proposed by J. P. Anosova, and V. V. Orlov in 1990, who included Castor and Fomalhaut in the group. In a study published in 1999, Barrado y Navascues estimated an age of 200 million years for the group and presented a list of 16 members, including Vega, Fomalhaut, Alderamin and Zubenelgenubi. However, in a paper published in 2013, a team led by Eric E. Mamajek argued that the stars, or at least the well-known members, including Castor, did not share a common origin because the velocity differences between them were too large, and the stars were even more separated 10 million years ago than they are now.
GJ 1214b

GJ 1214b is a planet located 48 light-years away from Earth in the constellation Ophiuchus. It is a complete ocean with no surface, which goes all the way down to the core. The bottom of the Ocean is made out of Ice, but not because it is cold, it's because the pressure down there is so immense. Scientists have called this 'Ice' Ice 7. Just imagine what creatures could be living in the oceans of this planet. It is a super-Earth, meaning it is larger than Earth but is significantly smaller (in mass and radius) than the gas giants of the Solar System. After CoRoT-7b, it was the second super-Earth to be known and is the first of a new class of planets with small size and relatively low density. GJ 1214 b is also significant because its parent star is relatively near the Sun and because it transits (crosses in front of) that parent star, which allows the planet's atmosphere to be studied using spectroscopic methods. In December 2013, NASA reported that clouds may have been detected in the atmosphere of GJ 1214 b.

## Discovery

GJ 1214 b was first detected by the MEarth Project, which searches for the small dips in brightness that can occur when an orbiting planet briefly passes in front of its parent star. In early 2009, the astronomers running the project noticed that the star GJ 1214 appeared to show dips in brightness of that sort. They then observed the star more closely and confirmed that it dimmed by roughly 1.5% every 1.58 days. Follow-up radial-velocity measurements were then made with the HARPS spectrograph on the ESO's 3.6-meter telescope at La Silla, Chile; those measurements succeeded in providing independent evidence for the reality of the planet. A paper was then published in *Nature* announcing the planet and giving estimates of its mass, radius, and orbital parameters.
Triton

Voyager 2 photomosaic of Triton's sub-Neptunian hemisphere

Triton is the largest natural satellite of the planet Neptune and the 7th largest in the Solar System, and was the first Neptunian moon to be discovered, on October 10, 1846, by English astronomer William Lassell. Triton makes up 99.5% of the mass of all objects orbiting Neptune. It is the only large moon in the Solar System with a retrograde orbit, an orbit in the direction opposite to its planet's rotation. Because of its retrograde orbit and composition similar to Pluto, Triton is thought to have been a dwarf planet, captured from the Kuiper belt.

It is the only satellite of Neptune massive enough to be in hydrostatic equilibrium, the second-largest planetary moon in relation to its primary (after Earth's Moon), and larger than Pluto. Triton is one of the few moons in the Solar System known to be geologically active (the others being Jupiter's Io and Europa, and Saturn's Enceladus and Titan). As a consequence, its surface is relatively young, with few obvious impact craters. Intricate cryovolcanic and tectonic terrains suggest a complex geological history.

Triton has a surface of mostly frozen nitrogen, a mostly water-ice crust, an icy mantle and a substantial core of rock and metal. The core makes up two thirds of its total mass. The mean density is 2.061 g/cm3, reflecting a composition of approximately 15–35% water ice.

During its 1989 flyby of Triton, Voyager 2 found surface temperatures of −235°C, and also discovered active geysers erupting sublimated nitrogen gas, contributing to a tenuous nitrogen atmosphere less than 1⁄70000 the pressure of Earth's atmosphere at sea level. Voyager 2 remains the only spacecraft to visit Triton. As the probe was only able to study about 40% of the moon's surface, future missions have been proposed to revisit the Neptune system with a focus on Triton.
Polaris

Polaris (Also known as the North Star) is a star located around 433 light-years from Earth in the constellation Ursa Minor. It is the closest relatively bright star to the north celestial pole. It lies less than 1° from the North Pole. Although it seems like a single point to the naked eye, it is actually a triple star system, composed of the primary yellow supergiant designated Polaris Aa in an orbit with a smaller companion Polaris Ab with Polaris b in a wider orbit. Polaris AB was discovered in 1779 by William Herschel.

The proximity of Polaris to the north celestial pole in the sky means that its distance from the horizon matches the observer’s latitude. For observers at the North Pole, the star is directly overhead, and the further south the observer is, the closer the star is to the northern horizon.  For example, observers in New York can see it 41 degrees above the horizon because the city is located at latitude 41°N.

Research conducted in the last two decades suggests that Polaris is 4.6 times brighter today than it was at the time Ptolemy observed it (137 CE). A team of scientists began to monitor the star in 1999 and discovered that, after reaching a minimum, the amplitude of the star’s pulsations was increasing again. As they researched historical records, they discovered that the star was fainter the further back they went.
V1400 Centauri

V1400 Centauri is a star located 434 light-years away in the constellation Centaurus. It is a relatively young star at only 16,000,000 years old and its mass is roughly 90% that of the Sun. The star has an apparent magnitude of 12.3 and requires a telescope to be seen. In 2007, V1400 Centauri was observed to be eclipsed and orbited by at least one major body, J1407b, thought to be either a large gas giant planet or a brown dwarf, with an immense ring system. Subsequent observations have not successfully detected J1407b, suggesting that it is on a highly eccentric orbit around the star. By 2021, it was discovered the parent star is strongly variable, with a 5.4-year long magnetic activity cycle, and no evidence was detected of additional planets or a repeat of the deep eclipses attributed to a transiting ring system.
Mimas

Mimas as taken by Cassini

Mimas is the seventh-largest moon of Saturn and the 21st largest in the Solar System. It was discovered on September 17th, 1789 by William Herschel. With a diameter of 396 kilometres (246 mi), it is the smallest astronomical body that is known to still be rounded in shape because of self-gravitation. However, Mimas is not actually in hydrostatic equilibrium for its current rotation. Mimas is the innermost rounded moon of Saturn. At a mean distance of just over 186,000 kilometres from the massive planet, Mimas takes only 22 hours and 36 minutes to complete an orbit. Mimas is tidally locked: it keeps the same face toward Saturn as it flies around the planet, just as our Moon does with Earth. Most of the Mimas surface is saturated with impact craters ranging in size up to greater than 40 kilometres in diameter. However, the craters in the South Pole region of Mimas are generally 20 kilometres in diameter or less. This suggests that some melting or other resurfacing processes occurred there later than on the rest of the moon.

Its most distinguishing feature is a giant impact crater – named Herschel Crater after the moon's discoverer – which stretches a third of the way across the face of the moon, making it look like the Death Star from “Star Wars.” The Herschel Crater is 130 kilometres across – one third of the diameter of the moon itself – with outer walls about 5 kilometres high and a central peak 6 km high. The impact that blasted this crater out of Mimas probably came close to breaking the moon apart. Shock waves from the Herschel impact may have caused the fractures, also called chasmata, on the opposite side of Mimas.

The fact that Mimas appears to be frozen solid is puzzling because Mimas is closer to Saturn and has a much more eccentric (elongated) orbit than Enceladus, which should mean that Mimas has more tidal heating than Enceladus. Yet Enceladus displays geysers of water, which implies internal heat, while Mimas has one of the most heavily cratered surfaces in the solar system, which suggests a frozen surface that has persisted for enough time to preserve all those craters. This paradox has prompted the “Mimas Test” by which any theory that claims to explain the partially thawed water of Enceladus must also explain the entirely frozen water of Mimas.
Alpha Centauri B

Alpha Centauri System compared to the Sun

Alpha Centauri B is one of the Closest Stars to Earth at 4.37 light-years. It is part of a triple binary system. It consists of Alpha Centauri A, Alpha Centauri B and the closest Proxima Centauri. To the naked eye, the three stars appear as 1 star with a magnitude of -0.27. Alpha Centauri B is a main-sequence star, like the Sun. But, it is 90% less massive and 14% smaller than the Sun. Although it has a lower luminosity than Alpha Centauri A, it emits more energy in the X-Ray band. Its light curve varies on a short timescale, and there has been at least one observed flare. Alpha Centauri B is more magnetically active than Alpha Centauri A. It has an apparent magnitude of 1.35, slightly dimmer than Alpha Centauri A.

## Star System

Alpha Centauri AB orbit a barycentre somewhere between Alpha Centauri A and Alpha Centauri B. Proxima Centauri then orbits this barycentre at a distance of 8700 AU. The A and B components of Alpha Centauri have an orbital period of 79.762 years. Their orbit is moderately eccentric, as it has an eccentricity of almost 0.52; their closest approach or periastron is 11.2 AU, or about the distance between the Sun and Saturn; and their furthest separation or apastron is 35.6 AU, about the distance between the Sun and Pluto. The most recent periastron was in August 1955 and the next will occur in May 2035; the most recent apastron was in May 1995 and will next occur in 2075.
HD 209458-b

HD 209458-b is an exoplanet located 159 light-years away from Earth. It orbits extremely close to its parent star at only 0.047AU, or one eighth of the radius of Mercury's orbit. This means that its Year is very short, at only 3.5 days. It also means that it is extremely hot at 1,000°C. In July 2014, NASA announced finding very dry atmospheres on three exoplanets (HD 189733b, HD 209458b, WASP-12b) orbiting sun-like stars. Although HD 209458b could not be seen directly, its passages between its star and Earth provided important information about its physical properties and atmosphere that was not otherwise available. Observations of spectral lines of carbon monoxide in HD 209458b’s atmosphere showed that winds with speeds of thousands of kilometres per hour travel from the planet’s dayside to its nightside.

## Discovery

Spectroscopic studies first revealed the presence of a planet around HD 209458 on November 5, 1999. Astronomers had made careful photometric measurements of several stars known to be orbited by planets, in the hope that they might observe a dip in brightness caused by the transit of the planet across the star's face. This would require the planet's orbit to be inclined such that it would pass between the Earth and the star, and previously no transits had been detected.

Soon after the discovery, separate teams, one led by David Charbonneau including Timothy Brown and others, and the other by Gregory W. Henry, were able to detect a transit of the planet across the surface of the star, making it the first known transiting extrasolar planet. On September 9 and 16, 1999, Charbonneau's team measured a 1.7% drop in HD 209458's brightness, which was attributed to the passage of the planet across the star. On November 8, Henry's team observed a partial transit, seeing only the ingress. Initially unsure of their results, the Henry group decided to rush their results to publication after overhearing rumours that Charbonneau had successfully seen an entire transit in September. Papers from both teams were published simultaneously in the same issue of the Astrophysical Journal. Each transit lasts about three hours, during which the planet covers about 1.5% of the star's face.

The star had been observed many times by the Hipparcos satellite, which allowed astronomers to calculate the orbital period of HD 209458-b very accurately at 3.524736 Earth Days.
The Milky Way

The Milky Way is the Galaxy that we all live in. It is 110,000 light-years across and the second-largest galaxy in the local group after the Andromeda Galaxy. The Milky Way is considered a large Galaxy, although, it is quite small compared to other galaxies out there. The Black Hole in the centre of the galaxy is called Sagittarius A and is roughly 44,000,000Km (44 Million Km) in Diameter. From Earth, the Milky Way appears as a band because its disk-shaped structure is viewed from within. Galileo Galilei first resolved the band of light into individual stars with his telescope in 1610. Until the early 1920s, most astronomers thought that the Milky Way contained all the stars in the Universe. Following the 1920 Great Debate between the astronomers Harlow Shapley and Heber Curtis, observations by Edwin Hubble showed that the Milky Way is just one of many galaxies.

The Milky Way is a barred spiral galaxy with an estimated visible diameter of 100,000–200,000 light-years, but only about 1000 light years thick at the spiral arms (more at the bulge). Recent simulations suggest that a dark matter area, also containing some visible stars, may extend up to a diameter of almost 2 million light-years. The Milky Way has several satellite galaxies and is part of the Local Group of galaxies, which form part of the Virgo Supercluster, which is itself a component of the Laniakea Supercluster.

It is estimated to contain 100–400 billion stars and at least that number of planets. The Solar System is located at a radius of about 27,000 light-years from the Galactic Center, on the inner edge of the Orion Arm, one of the spiral-shaped concentrations of gas and dust. The stars in the innermost 10,000 light-years form a bulge and one or more bars that radiate from the bulge. The Galactic Center is an intense radio source known as Sagittarius A\*, a supermassive black hole of 4,100,000 solar masses. Stars and gases at a wide range of distances from the Galactic Center orbit at approximately 220 kilometres per second. The constant rotational speed appears to contradict the laws of Keplerian dynamics and suggests that much (about 90%) of the mass of the Milky Way is invisible to telescopes, neither emitting nor absorbing electromagnetic radiation. This conjectural mass has been termed “dark matter”. The rotational period is about 240 million years at the radius of the Sun.
PSR B1620-26 b

PSR B1620-26 b is an exoplanet located 12,400 light-years away from Earth in the constellation Scorpius. It bears the unofficial nicknames “Methuselah” and “the Genesis planet” (named after the Biblical character who, according to the Bible, lived to be the oldest person) due to its extreme age. The planet is in a circumbinary orbit around the two stars of PSR B1620-26 (which are a pulsar (PSR B1620-26 A) and a white dwarf (WD B1620-26)) and is the first circumbinary planet ever confirmed. It is also the first planet found in a globular cluster. The planet is one of the oldest known extrasolar planets, believed to be about 12.7 billion years old.

## Discovery

Like nearly all extrasolar planets discovered prior to 2008, PSR B1620-26 b was originally detected through the Doppler shifts its orbit induces on radiation from the star it orbits (in this case, changes in the apparent pulsation period of the pulsar). In the early 1990s, a group of astronomers led by Donald Backer, who were studying what they thought was a binary pulsar, determined that a third object was needed to explain the observed Doppler shifts. Within a few years, the gravitational effects of the planet on the orbit of the pulsar and white dwarf had been measured, giving an estimate of the mass of the third object that was too small for it to be a star. The conclusion that the third object was a planet was announced by Stephen Thorsett and his collaborators in 1993.

The study of the planetary orbit allowed the mass of the white dwarf star to be estimated as well, and theories of the formation of the planet suggested that the white dwarf should be young and hot. On July 10, 2003, the detection of the white dwarf and confirmation of its predicted properties were announced by a team led by Steinn Sigurdsson, using observations from the Hubble Space Telescope. It was at a NASA press briefing that the name Methuselah was introduced, capturing press attention around the world.

## Characteristics

#### Mass, orbit and age

PSR B1620-26 b has the mass of 2.5 Jupiters and orbits at 23 Astronomical Units (AU) (Slightly farther than Uranus). It takes 100 years to orbit its star once. What makes PSR B1620-26 b special is that it orbits a pulsar and a white dwarf binary pair. It is also the oldest planet ever discovered at 12.7 billion years old, 1 billion years younger than the Universe and nearly 3 times as old as Earth.
51 Pegasi b

51 Pegasi b or officially named Dimidium is an exoplanet located 50 light-years away from Earth in the constellation Pegasus. It was the first exoplanet to be discovered orbiting a main-sequence star, the Sun-like star 51 Pegasi, and marked a breakthrough in astronomical research. It is the prototype for a class of planets called hot Jupiters. In 2017, traces of water were discovered in the planet's atmosphere. In 2019, the Nobel Prize in Physics was awarded in part for the discovery of 51 Pegasi b. Its presence was deduced in 1995 from the wobble that its gravity induces in the parent star’s motion in a 4.23-day cycle. Swiss astronomers Michel Mayor and Didier Queloz were the first to find a planet through such induced motions, and the discovery of 51 Pegasi b led to thousands more extrasolar planets being found. It has a mass 46 percent that of Jupiter, but has a radius 1.9 times that of Jupiter because it is 'inflated' by its star’s heat.
Thestias

Thestias is an exoplanet orbiting the star Pollux, 34 light-years away from Earth, in the constellation Gemini. It was discovered in 2006 by astronomer Artie P. Hatzes. It has over twice the mass of Jupiter, but the diameter is currently unknown. Scientists suspected its presence since 1993, when a team at University of Texas at Austin measured precise relative radial velocities for three class K giant stars: Pollux, Arcturus and Aldebaran. They found long-period variations in the relative radial velocity of all three stars (a period of 558 days for Pollux), too long to be a result of radial pulsations. The team concluded that these variations might be due either to non-radial pulsations, to a surface feature combined with rotation, or to the presence of a substellar companion with a mass 3 to 12 times that of Jupiter. Thestias orbits Pollux at a distance of 1.64AU (slightly farther than Mars is from the Sun) in a near circular orbit and completes one orbit in 1.62 Earth years.

## Name

The exoplanet was named through public voting and suggestions. In 2015 the winning name was Thestias though it could have been Leda – Pollux’s mother in Greek and Roman mythology – however, the name was already attributed to an asteroid and to one of Jupiter’s satellites.

## Discovery

The existence of an exoplanet around Pollux was suspected since 1993, however, it was only in 2006 when the planet’s existence was finally confirmed.
Algol A

Algol A is a star located 90 light-years away from Earth in the constellation Perseus. It is also known as the demon star and is a triple binary system. Thus, Algol's magnitude is usually near-constant at 2.1, but regularly dips to 3.4 every 2.86 days during the roughly 10-hour-long partial eclipses. It may have been the first variable star discovered. Algol came within 9.8 light years of the Sun 7.3 million years ago. At the time, it shone at magnitude -2.5, which is about a magnitude brighter than Sirius (magnitude -1.47) today. The system’s gravity may have disrupted the Oort cloud at its closest approach, possibly deflecting numerous comets into the inner solar system. However, a study published in 1999 showed that passing stars do not perturb the Oort cloud to such a degree as to cause a considerable increase in the number of comets near the Earth’s orbit.

## Name

*Beta Persei* is the star's Bayer designation. The name *Algol* derives from Arabic رأس الغول : head of the ogre. The English name Demon Star was taken from the Arabic name. In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) to catalogue and standardize proper names for stars. The WGSN's first bulletin of July 2016 included a table of the first two batches of names approved by the WGSN; which included *Algol* for this star. It is so entered on the IAU Catalogue of Star Names.
Proxima Centauri

Alpha Centauri System compared to the Sun

Proxima Centauri is a Red Dwarf star and is the closest star to us. Despite this, it is still 4.22 light-years away. It orbits around the binary star system Alpha Centauri AB and is 2.18° to the southwest of the Alpha Centauri AB pair. It is currently 12,950 AU (0.2 ly) from AB, which it orbits with a period of about 550,000 years. Proxima Centauri has an apparent magnitude of 11.13, 20,000 times dimmer than the Sun. Its mass is about 12% that of the Sun's and even though it's the closest star to the Sun, it's too dim to be seen with the naked eye.

Although it has a very low average luminosity, Proxima Centauri is a flare star that randomly undergoes dramatic increases in brightness because of magnetic activity. The star's magnetic field is created by convection throughout the stellar body, and the resulting flare activity generates a total X-ray emission similar to that produced by the Sun. The internal mixing of its fuel by convection through its core, and Proxima's relatively low energy-production rate, mean that it will be a main-sequence star for another four trillion years.

Proxima Centauri has three known exoplanets: Proxima Centauri b, Proxima Centauri c, and Proxima Centauri d. Proxima Centauri b orbits the star at a distance of roughly 0.05 AU (7.5 million km) with an orbital period of approximately 11.2 Earth days. Its estimated mass is at least 1.17 times that of Earth. Proxima Centauri b orbits within Proxima Centauri's habitable zone, but because Proxima Centauri is a red dwarf and a flare star, the planet's habitability is disputed. A candidate super-Earth, Proxima Centauri c, orbits roughly 1.5 AU (220 million km) away every 1,900 d (5.2 yr). A sub-Earth, Proxima Centauri d, orbits roughly 0.029 AU (4.3 million km) away every 5.1 days.
Mercury

Mercury is the smallest planet in the solar system. It is so small that some moons in the Solar System are larger than it (Ganymede, Jupiter's moon and Titan, Saturn's Moon). Because of its small size, the core of the planet is cooling quite rapidly. Because of this, the crust of the planet is cracking and shrinking as the core cools.

Even though Mercury is the closest planet from the Sun, it is not the hottest, that trophy belongs to Venus. In fact, it is the place with the most varying temperature in the Solar System. Because of its lack of atmosphere, it struggles to retain heat, meaning during the day, the temperature can go up to a boiling 462°C (about the same temperature as Venus) but during the night the temperature drops to a freezing -172°C.

If you were to stand on the surface of Mercury, the Sun would appear 3 times the size as it does on Earth. The core of Mercury actually consists of 85% of the volume of the planet. The theory behind this is that a large object collided with Mercury long ago, which stripped off most of the planet. Similar to Venus, Mercury orbits the Sun within Earth's orbit as an inferior planet, and its apparent distance from the Sun as viewed from Earth never exceeds 28°. This proximity to the Sun means the planet can only be seen near the western horizon after sunset or the eastern horizon before sunrise, usually in twilight. At this time, it may appear as a bright star-like object, but is more difficult to observe than Venus. From Earth, the planet telescopically displays the complete range of phases, similar to Venus and the Moon, which recurs over its synodic period of approximately 116 days.

Mercury rotates in a way that is unique in the Solar System. It is tidally locked with the Sun in a 3:2 spin–orbit resonance, meaning that relative to the fixed stars, it rotates on its axis exactly three times for every two revolutions it makes around the Sun. As seen from the Sun, in a frame of reference that rotates with the orbital motion, it appears to rotate only once every two Mercurian years. An observer on Mercury would therefore see only one day every two Mercurian years. Mercury's axis has the smallest tilt of the Solar System's planets (about 1⁄30 degree). Its orbital eccentricity is the largest of all known planets in the Solar System; at perihelion, Mercury's distance from the Sun is only about two-thirds (or 66%) of its distance at aphelion.

Two spacecraft have visited Mercury: Mariner 10 flew by in 1974 and 1975; and MESSENGER, launched in 2004, orbited Mercury over 4,000 times in four years before exhausting its fuel and crashing into the planet's surface on April 30, 2015. The BepiColombo spacecraft is planned to arrive at Mercury in 2025.
Whirlpool Galaxy

The Whirlpool Galaxy is a galaxy 31,000,000 light-years away from Earth in the constellation Canes Venatici. It is also known as Messier 51, M51 or NGC 5194. It was the first galaxy to be classed as a spiral galaxy. The galaxy is easily observed by a telescope and even binoculars. The Whirlpool Galaxy has been extensively observed by professional astronomers, who study it to understand galaxy structure (particularly structure associated with the spiral arms) and galaxy interactions. Another galaxy close to the Whirlpool Galaxy called NGC 5195 is interacting with the spiral arms. The Whirlpool galaxy has a very fast rate of star formation. This is due to its collision with NGC 5195, which has essentially merged the two together.

## Discovery

The whirlpool galaxy was discovered by Charles Messier in 1773 and was designated in Messier's catalogue as M51. Its companion galaxy, NGC 5195, was discovered in 1781 by Pierre Méchain, although it was not known whether it was interacting or merely another galaxy passing at a distance. In 1845, William Parsons, 3rd Earl of Rosse, employing a 72-inch (1.8 m) reflecting telescope at Birr Castle, Ireland, found that the Whirlpool possessed a spiral structure, the first “nebula” to be known to have one. These “spiral nebulae” were not recognized as galaxies until Edwin Hubble was able to observe Cepheid variables in some of these spiral nebulae, which provided evidence that they were so far away that they must be entirely separate galaxies. The advent of radio astronomy and subsequent radio images of M51 unequivocally demonstrated that the Whirlpool and its companion galaxy are indeed interacting. Sometimes the designation M51 is used to refer to the pair of galaxies, in which case the individual galaxies may be referred to as M51a (Whirlpool Galaxy) and M51b (NGC 5195).
Harriot

Harriot is one of the main characters in Harry and Harriot.

## Appearance

Harriot seems to be based off Harry. He legs are also black, her eyes are also black and her body is also silver. The only difference is that her legs are longer.

## Personally

Harriot seems to just go for things as she said in the first episode "Screw it, can i be ur GF".

## Trivia

* Harriot is also the name of Chili's Sister, who is related to Ethanos Squad and so is CJ, meaning Harriot's name might based off Chili's sister.
* It is unknown if Harriot is also created by CJ's Grandad, but it seems like it.
Vy Canis Majoris

VY Canis Majoris is a red hypergiant star located roughly 3,900 light-years away from Earth. It is extremely Oxygen rich. It is one of the largest known stars, one of the most luminous and massive stars discovered. Not only that, but it is about 17 to 20 times the mass of the Sun. The diameter of VY Canis Majoris is about 1420 times that of the sun and a volume of over 8 billion times that of the sun. Most stars end their lives in a supernova explosion, in the case of VY Canis Majoris, it will end its life in something around 100 times greater than a supernova, a hypernova. VY Canis Majoris has an average density of 5.33 to 8.38 mg/m3, it is over 100,000 times less dense than Earth’s atmosphere at sea level. It is embedded within the large molecular cloud called Sh2-310. This is one of the largest star-forming H II regions, which has a diameter of around 480 arcminutes / 681 light-years. VY Canis Majoris is a very young star, and it is believed that it evolved from an O9 main-sequence star which initially had between 5 – 20 solar radii. The star evolved quickly due to its high mass and has spent its time in the red hypergiant phase for around 100,000 to 500,000 years, thus the star has left its main sequence more than a million years ago.
Pluto

Pluto is by far the most famous dwarf planet. It was discovered in 1930 by Clyde W. Tombaugh, and it was classed as a planet. It was only in 2008 scientists discovered that it was too small to be a planet and decided to reclassify it to be a dwarf planet. Pluto has 5 moons called Charon, Nix, Hydra, Styx and Kerberos, all relatively small. Charon, the biggest, is big enough to have a gravitational impact on Pluto and nearly orbit each other. It takes Pluto 248 days to orbit The Sun due to the fact that it's so far away from it. It is on average 39.5 times further away from the sun than Earth, meaning it is also very cold, -229°C on average. Pluto has a very elliptical orbit, meaning it sometimes comes closer to the Sun than Neptune.

## Discovery

In the 1840s, Urbain Le Verrier used Newtonian mechanics to predict the position of the then-undiscovered planet Neptune after analysing perturbations in the orbit of Uranus. Subsequent observations of Neptune in the late 19th century led astronomers to speculate that Uranus's orbit was being disturbed by another planet besides Neptune.

In 1906, Percival Lowell—a wealthy Bostonian who had founded Lowell Observatory in Flagstaff, Arizona, in 1894—started an extensive project in search of a possible ninth planet, which he termed “Planet X”. By 1909, Lowell and William H. Pickering had suggested several possible celestial coordinates for such a planet. Lowell and his observatory conducted his search until his death in 1916, but to no avail. Unknown to Lowell, his surveys had captured two faint images of Pluto on March 19 and April 7, 1915, but they were not recognized for what they were. There are fourteen other known precovery observations, with the earliest made by the Yerkes Observatory on August 20, 1909.

Percival's widow, Constance Lowell, entered into a ten-year legal battle with the Lowell Observatory over her husband's legacy, and the search for Planet X did not resume until 1929. Vesto Melvin Slipher, the observatory director, gave the job of locating Planet X to 23-year-old Clyde Tombaugh, who had just arrived at the observatory after Slipher had been impressed by a sample of his astronomical drawings.

Tombaugh's task was to systematically image the night sky in pairs of photographs, then examine each pair and determine whether any objects had shifted position. Using a blink comparator, he rapidly shifted back and forth between views of each of the plates to create the illusion of movement of any objects that had changed position or appearance between photographs. On February 18, 1930, after nearly a year of searching, Tombaugh discovered a possible moving object on photographic plates taken on January 23 and 29. A lesser-quality photograph taken on January 21 helped confirm the movement. After the observatory obtained further confirmatory photographs, news of the discovery was telegraphed to the Harvard College Observatory on March 13, 1930.

Pluto has yet to complete a full orbit of the Sun since its discovery, as one Plutonian year is 247.68 years long.
Umbriel

Umbriel is the third-largest moon of Uranus and orbits at an average distance of 266,000Km. It was discovered on October 24th 1851 by William Lassell. It was discovered at the same time as Ariel and named after a character in Alexander Pope's poem *The Rape of the Lock*. Umbriel consists mainly of ice with a substantial fraction of rock, and may be differentiated into a rocky core and an icy mantle. The surface is the darkest among Uranian moons, and appears to have been shaped primarily by impacts. However, the presence of canyons suggests early endogenic processes, and the moon may have undergone an early endogenically driven resurfacing event that obliterated its older surface.

Covered by numerous impact craters reaching 210 km (130 mi) in diameter, Umbriel is the second most heavily cratered satellite of Uranus after Oberon. The most prominent surface feature is a ring of bright material on the floor of Wunda crater. This moon, like all moons of Uranus, probably formed from an accretion disk that surrounded the planet just after its formation. The Uranian system has been studied up close only once, by the spacecraft *Voyager 2* in January 1986. It took several images of Umbriel, which allowed mapping of about 40% of the moon's surface.
Chariklo

Chariklo (designated 10199 Chariklo) is the largest confirmed Centaur in the Solar System. It orbits the Sun between Saturn and Uranus, just grazing the Orbit of Uranus. On 26 March 2014, astronomers announced the discovery of two rings (nicknamed as the rivers Oiapoque and Chuí) around Chariklo by observing a stellar occultation, making it the first minor planet known to have rings. Chariklo was discovered by James V. Scotti of the Spacewatch program on February 15, 1997. Infrared observations of Chariklo indicate the presence of water ice, which may in fact be located in its rings. Michael Brown's website lists it as possibly a dwarf planet with a measured diameter of 232 km.

## Orbit

Chariklo's orbit is highly unstable since it is a centaur. It will likely lead to either being ejected out of the solar system or a collision with another object, or transition into a short-period comet.

The orbit of Chariklo is more stable than those of Nessus, Chiron, and Pholus. Chariklo lies within 0.09 AU of the 4:3 resonance of Uranus and is estimated to have a relatively long orbital half-life of about 10.3 Myr. Orbital simulations of twenty clones of Chariklo suggest that Chariklo will not start to regularly come within 3 AU of Uranus for about thirty thousand years.
MakeMake

Makemake is a dwarf planet located in the Kuiper Belt, meaning it's classed as a KBO (Kuiper Belt Object). It has a very low average temperature from 40K – 30K (-230°C - -240°C). It has a diameter of approximately 60% of Pluto and has one known satellite. Its surface is covered with frozen methane, ethane and nitrogen. In July 2008, it was named after Makemake, a creator god in the Rapa Nui mythology of Easter Island. Makemake is large enough and bright enough to be studied by high-end amateur telescopes. Makemake has one satellite, a dim lightened moon that was named MK 2. The Dwarf Planet was the fourth dwarf planet discovered. Its discovery along with that of Eris and Haumea contributed to Pluto’s reclassification as a planet to a dwarf planet. It takes about 7 hours and 22 minutes for Makemake’s light to reach Earth. Makemake is the second-furthest dwarf planet from the Sun and the third-largest known dwarf planet in the Solar System.
Crab Pulsar

The Crab Pulsar is a Neutron Star/Pulsar located 6,400 light-years away from Earth in the constellation Taurus. It is a young neutron star at not even 1,000 years old. It is the central neutron star of the Crab Nebula and a remnant of the Supernova SN 1054 which was widely observed on Earth in the year 1054. Discovered in 1968, the pulsar was the first to be connected with a supernova remnant. The Crab Pulsar is one of the very few to be identified optically. The pulsar is roughly 20Km across and rotates every 33 milliseconds or 30 times per second. The outflowing relativistic wind from the neutron star generates synchrotron emission, which produces the bulk of the emission from the nebula, seen from radio waves through to gamma rays. The period of the pulsar's rotation is increasing by 38 nanoseconds per day due to the large amounts of energy carried away in the pulsar wind.

The Crab Nebula is often used as a calibration source in X-ray astronomy. It is very bright in X-rays, and the flux density and spectrum are known to be constant, except the pulsar itself. The pulsar provides a strong periodic signal that is used to check the timing of the X-ray detectors. In X-ray astronomy, “crab” and “millicrab” are sometimes used as units of flux density.
Asteroid Belt

The asteroid belt is a huge cluster of asteroids between the orbits of Mars and Jupiter. It was formed around the time the Sun and all the planets were born. In films, you can see that the asteroids in the asteroid belt are very close together. This is however wrong, the asteroids in the asteroid belt are separated far apart that even unmanned spacecraft have gone through easily without human interference. Nonetheless, collisions between large asteroids occur and can produce an asteroid family, whose members have similar orbital characteristics and compositions. The asteroid belt is the smallest and innermost known circumstellar disc in the Solar System.

About half its mass is contained in the four largest asteroids: Ceres, Vesta, Pallas, and Hygiea. The total mass of the asteroid belt is about 4% that of the Moon. Ceres, the only object in the asteroid belt large enough to be a dwarf planet, is about 950 km in diameter, whereas Vesta, Pallas, and Hygiea have mean diameters less than 600 km. The remaining bodies range down to the size of a dust particle.

The asteroid belt formed from the primordial solar nebula as a group of planetesimals. Planetesimals are the smaller precursors of the protoplanets. Between Mars and Jupiter, however, gravitational perturbations from Jupiter imbued the protoplanets with too much orbital energy for them to accrete into a planet. Collisions became too violent, and instead of fusing together, the planetesimals and most of the protoplanets shattered. As a result, 99.9% of the asteroid belt's original mass was lost in the first 100 million years of the Solar System's history. Some fragments eventually found their way into the inner Solar System, leading to meteorite impacts with the inner planets. Asteroid orbits continue to be appreciably perturbed whenever their period of revolution about the Sun forms an orbital resonance with Jupiter. At these orbital distances, a Kirkwood gap occurs as they are swept into other orbits.

On 22 January 2014, European Space Agency (ESA) scientists reported the detection, for the first definitive time, of water vapour on Ceres, the largest object in the asteroid belt. The detection was made by using the far-infrared abilities of the Herschel Space Observatory. The finding was unexpected because comets, not asteroids, are typically considered to “sprout jets and plumes”. According to one of the scientists, “The lines are becoming more and more blurred between comets and asteroids”.