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WASP-60
WASP-60 is a F-type main-sequence star about 1420 light-years away. The stars age is much younger than the Sun's at 1.7 billion years. WASP-60 is enriched in heavy elements, having 180% of the solar abundance of iron. The star does not have noticeable starspot activity, an unexpected observation for a relatively young star. The age of WASP-60 determined by different methods is highly discrepant though, and it may actually be an old star which experienced an episode of spin-up in the past. The star was named Morava in 2019 by Serbian amateur astronomers as part of the NameExoWorlds contest. A multiplicity survey in 2015 did not detect any stellar companions to WASP-60. Planetary system In 2012 a transiting hot Jupiter planet b was detected on a tight, circular orbit. The planet was named ''Vlasina'' by Serbian astronomers in December 2019. Its equilibrium temperature is . Measurement of the Rossiter–McLaughlin effect The Rossiter–McLaughlin effect is a spectros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pegasus (constellation)
Pegasus is a constellation in the northern sky, named after the winged horse Pegasus in Greek mythology. It was one of the 48 constellations listed by the 2nd-century astronomer Ptolemy, and is one of the 88 constellations recognised today. With an apparent magnitude varying between 2.37 and 2.45, the brightest star in Pegasus is the orange supergiant Epsilon Pegasi, also known as Enif, which marks the horse's muzzle. Alpha (Markab), Beta (Scheat), and Gamma (Algenib), together with Alpha Andromedae (Alpheratz) form the large asterism known as the ''Square of Pegasus''. Twelve star systems have been found to have exoplanets. 51 Pegasi was the first Sun-like star discovered to have an exoplanet companion. Mythology The Babylonian constellation IKU (field) had four stars of which three were later part of the Greek constellation ''Hippos'' (Pegasus). Pegasus, in Greek mythology, was a winged horse with magical powers. One myth regarding his powers says that his hooves dug o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Main Sequence
In astronomy, the main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hertzsprung and Henry Norris Russell. Stars on this band are known as main-sequence stars or dwarf stars. These are the most numerous true stars in the universe and include the Sun. After condensation and ignition of a star, it generates thermal energy in its dense core region through nuclear fusion of hydrogen into helium. During this stage of the star's lifetime, it is located on the main sequence at a position determined primarily by its mass but also based on its chemical composition and age. The cores of main-sequence stars are in hydrostatic equilibrium, where outward thermal pressure from the hot core is balanced by the inward pressure of gravitational collapse from the overlying layers. The strong dependence of the rate of energy ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
F-type Main-sequence Star
An F-type main-sequence star (F V) is a main-sequence, hydrogen-fusing star of spectral type F and luminosity class V. These stars have from 1.0 to 1.4 times the mass of the Sun and surface temperatures between 6,000 and 7,600 K.Tables VII and VIII. This temperature range gives the F-type stars a whitish hue when observed by the atmosphere. Because a main-sequence star is referred to as a dwarf star, this class of star may also be termed a yellow-white dwarf (not to be confused with white dwarfs, remnant stars that are a possible final stage of stellar evolution). Notable examples include Procyon A, Gamma Virginis A and B, and KIC 8462852. Spectral standard stars The revised Yerkes Atlas system (Johnson & Morgan 1953) listed a dense grid of F-type dwarf spectral standard stars; however, not all of these have survived to this day as stable standards. The ''anchor points'' of the MK spectral classification system among the F-type main-sequence dwarf stars, i.e. those ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Starspot
Starspots are stellar phenomena, so-named by analogy with sunspots. Spots as small as sunspots have not been detected on other stars, as they would cause undetectably small fluctuations in brightness. The commonly observed starspots are in general much larger than those on the Sun: up to about 30% of the stellar surface may be covered, corresponding to starspots 100 times larger than those on the Sun. Detection and measurements To detect and measure the extent of starspots one uses several types of methods. *For rapidly rotating stars – Doppler imaging and Zeeman-Doppler imaging. With the Zeeman-Doppler imaging technique the direction of the magnetic field on stars can be determined since spectral lines are split according to the Zeeman effect, revealing the direction and magnitude of the field. *For slowly rotating stars – Line Depth Ratio (LDR). Here one measures two different spectral lines, one sensitive to temperature and one which is not. Since starspots have a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NameExoWorlds
NameExoWorlds (also known as IAU NameExoWorlds) is the name of various projects managed by the International Astronomical Union (I.A.U.) to encourage names to be submitted for astronomical objects, which would later be considered for official adoption by the organization. History The first such project (NameExoWorlds I), in 2015, regarded the naming of stars and exoplanets. 573,242 votes were submitted by members by the time the contest closed on October 31, 2015, and the names of 31 exoplanets and 14 stars were selected from these. Many of the names chosen were based on world history, mythology and literature. In June 2019, another such project (NameExoWorlds II), in celebration of the organization's hundredth anniversary, in a project officially called IAU100 NameExoWorlds, welcomed countries of the world to submit names for exoplanets and their host stars. A star with an exoplanet was assigned to each country, and members of the public submitted names for them. In August 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transit (astronomy)
In astronomy, a transit (or astronomical transit) is a phenomenon when a celestial body passes directly between a larger body and the observer. As viewed from a particular vantage point, the transiting body appears to move across the face of the larger body, covering a small portion of it. The word "transit" refers to cases where the nearer object appears smaller than the more distant object. Cases where the nearer object appears larger and completely hides the more distant object are known as ''occultations''. However, the probability of seeing a transiting planet is low because it is dependent on the alignment of the three objects in a nearly perfectly straight line. Many parameters of a planet and its parent star can be determined based on the transit. In the Solar System One example of a transit involves the motion of a planet between a terrestrial observer and the Sun. This can happen only with inferior planets, namely Mercury and Venus (see transit of Mercury ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hot Jupiter
Hot Jupiters (sometimes called hot Saturns) are a class of gas giant exoplanets that are inferred to be physically similar to Jupiter but that have very short orbital periods (). The close proximity to their stars and high surface-atmosphere temperatures resulted in their informal name "hot Jupiters". Hot Jupiters are the easiest extrasolar planets to detect via the radial-velocity method, because the oscillations they induce in their parent stars' motion are relatively large and rapid compared to those of other known types of planets. One of the best-known hot Jupiters is . Discovered in 1995, it was the first extrasolar planet found orbiting a Sun-like star. has an orbital period of about 4 days. General characteristics Though there is diversity among hot Jupiters, they do share some common properties. * Their defining characteristics are their large masses and short orbital periods, spanning 0.36–11.8 Jupiter masses and 1.3–111 Earth days. The mass ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rossiter–McLaughlin Effect
The Rossiter–McLaughlin effect is a spectroscopic phenomenon observed when an object moves across the face of a star. Description The Rossiter–McLaughlin effect is a spectroscopic phenomenon observed when either an eclipsing binary's secondary star or an extrasolar planet is seen to transit across the face of the primary or parent star. As the main star rotates on its axis, one quadrant of its photosphere will be seen to be coming towards the viewer, and the other visible quadrant to be moving away. These motions produce blueshifts and redshifts, respectively, in the star's spectrum, usually observed as a broadening of the spectral lines. When the secondary star or planet transits the primary, it blocks part of the latter's disc, preventing some of the shifted light from reaching the observer. That causes the observed mean redshift of the primary star as a whole to vary from its normal value. As the transiting object moves across to the other side of the star's disc, the r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G-type Main-sequence Stars
A G-type main-sequence star (Spectral type: G-V), also often, and imprecisely called a yellow dwarf, or G star, is a main-sequence star (luminosity class V) of spectral type G. Such a star has about 0.9 to 1.1 solar masses and an effective temperature between about 5,300 and 6,000 K. Like other main-sequence stars, a G-type main-sequence star is converting the element hydrogen to helium in its core by means of nuclear fusion, but can also fuse helium when hydrogen runs out. The Sun, the star in the center of the Solar System to which the Earth is gravitationally bound, is an example of a G-type main-sequence star (G2V type). Each second, the Sun fuses approximately 600 million tons of hydrogen into helium in a process known as the proton–proton chain (4 hydrogens form 1 helium), converting about 4 million tons of matter to energy. Besides the Sun, other well-known examples of G-type main-sequence stars include Alpha Centauri, Tau Ceti, Capella and 51 Pegasi. The term ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planetary Systems With One Confirmed Planet
Planetary means relating to a planet A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a ... or planets. It can also refer to: ;Science * Planetary habitability, the measure of an astronomical body's potential to develop and sustain life * Planetary nebula, an astronomical object ;People * Planetary (rapper), one half of east coast rap group OuterSpace ;Arts, entertainment, and media * ''Planetary'' (comics), a comic book series by Warren Ellis and John Cassaday * " Planetary (Go!)", a 2011 song by rock band My Chemical Romance * '' Planetary Radio'', a public radio show about space exploration, produced by The Planetary Society ;Organizations * The Planetary Society, the Earth's largest space interest group ;Technology * Epicyclic gearing (planetary gearing), an automotive tra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planetary Transit Variables
Planetary means relating to a planet or planets. It can also refer to: ;Science * Planetary habitability, the measure of an astronomical body's potential to develop and sustain life * Planetary nebula, an astronomical object ;People * Planetary (rapper), one half of east coast rap group OuterSpace ;Arts, entertainment, and media * ''Planetary'' (comics), a comic book series by Warren Ellis and John Cassaday * " Planetary (Go!)", a 2011 song by rock band My Chemical Romance * '' Planetary Radio'', a public radio show about space exploration, produced by The Planetary Society ;Organizations * The Planetary Society, the Earth's largest space interest group ;Technology * Epicyclic gearing An epicyclic gear train (also known as a planetary gearset) consists of two gears mounted so that the center of one gear revolves around the center of the other. A carrier connects the centers of the two gears and rotates the planet and sun gea ... (planetary gearing), an automotive transm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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