"the closest star to Earth after the Sun, is around 4.2 light-years away. Radar systems measure the distance to a target by the time it takes a radio-wave pulse to return to the radar antenna after being reflected by the target: the distance to the target is half the round-trip transit time multiplied by the speed of light. A Global Positioning System (GPS) receiver measures its distance to GPS satellites based on how long it takes for a radio signal to arrive from each satellite, and from these distances calculates the receiver's position. Because light travels about () in one"
"Solar System about the center of the Milky Way is approximately 251 km/s (156 mi/s). At this speed, it takes around 1,190 years for the Solar System to travel a distance of 1 light-year, or 7 days to travel 1 AU. The Milky Way is moving with respect to the cosmic microwave background radiation (CMB) in the direction of the constellation Hydra with a speed of 550 km/s, and the Sun's resultant velocity with respect to the CMB is about 370 km/s in the direction of Crater or Leo. The temperature of the photosphere is approximately 6,000 K, whereas the"
"As seen from Earth, the planet's orbital prograde motion makes the Sun appear to move with respect to other stars at a rate of about 1° (or a Sun or Moon diameter every 12 hours) eastward per solar day. Earth's orbital speed averages about 30 km/s (108,000 km/h; 67,000 mph), which is fast enough to cover the planet's diameter in 7 minutes and the distance to the Moon in 4 hours. From a vantage point above the north pole of either the Sun or Earth, Earth would appear to revolve in a counterclockwise direction around the Sun. From the same"
"the Sun is over 1.4 billion kilometers (9 AU). With an average orbital speed of 9.68 km/s, it takes Saturn 10,759 Earth days (or about years) to finish one revolution around the Sun. As a consequence, it forms a near 5:2 mean-motion resonance with Jupiter. The elliptical orbit of Saturn is inclined 2.48° relative to the orbital plane of the Earth. The perihelion and aphelion distances are, respectively, 9.195 and 9.957 AU, on average. The visible features on Saturn rotate at different rates depending on latitude and multiple rotation periods have been assigned to various regions (as in Jupiter's case)."
"Galactic year The galactic year, also known as a cosmic year, is the duration of time required for the Sun to orbit once around the center of the Milky Way Galaxy. Estimates of the length of one orbit range from 225 to 250 million terrestrial years. The Solar System is traveling at an average speed of 828,000 km/h (230 km/s) or 514,000 mph (143 mi/s) within its trajectory around the galactic center, a speed at which an object could circumnavigate the Earth's equator in 2 minutes and 54 seconds; that speed corresponds to approximately 1/1300 of the speed of light."
"approximately 5778 K () and ""V"" indicates that the Sun, like most stars, is a main-sequence star, and thus generates its energy via fusing hydrogen into helium. In its core, the Sun fuses about 620 million metric tons of hydrogen each second. The Earth's mean distance from the Sun is approximately , though the distance varies as the Earth moves from perihelion in January to aphelion in July. At this average distance, light travels from the Sun to Earth in about 8 minutes, 19 seconds. The energy of this sunlight supports almost all life on Earth by photosynthesis, and drives"
"186,000 miles per second. The sun weighs the same as 330,000 earths and is 95% hydrogen and helium gas and not solid. The Sun is compressed by gravity so tightly that the gas at the center is more than 100 times heavier than water with a pressure of one billion tons per square inch while the surface is about one pound per square inch. The center is 30 million degrees Fahrenheit while the surface is only 10,000 degrees, but the corona is 1 million degrees Fahrenheit though nobody knows why, so scientists study the corona during each solar eclipse. Dr."
"orbital speed of the Sun around the Galactic center, which is about 220 km/s and is included in the movement of the Local Standard of Rest. Thus the Sun gains distance towards the apex at about 1/13 its orbital speed. The sun's motion in the Milky Way is not confined to the galactic plane; it also shifts (""bobs"") up and down with respect to the plane over millions of years. The nature and extent of the solar motion was first demonstrated by William Herschel in 1783, who also first determined the direction for the solar apex to Lambda Herculis, only"
"Eventually, after billions more years, the Sun will finally cease to shine altogether, becoming a black dwarf. The Solar System travels alone through the Milky Way in a circular orbit approximately 30,000 light years from the Galactic Centre. Its speed is about 220 km/s. The period required for the Solar System to complete one revolution around the Galactic Centre, the galactic year, is in the range of 220–250 million years. Since its formation, the Solar System has completed at least 20 such revolutions. Various scientists have speculated that the Solar System's path through the galaxy is a factor in the"
"nearly the same now as they did hundreds of years ago. However, precise long-term observations show that the constellations change shape, albeit very slowly, and that each star has an independent motion. This motion is caused by the movement of the stars relative to the Sun and Solar System. The Sun travels in a nearly circular orbit (the ""solar circle"") about the center of the Milky Way at a speed of about 220 km/s at a radius of from the center, which can be taken as the rate of rotation of the Milky Way itself at this radius. The proper"
"Sun's radius. It has a quiet (inactive) chromosphere and is most likely an old star with an age over 12 billion years. The star is spinning slowly with a projected rotational velocity of 1.1 km/s. Since leaving the main sequence, it has increased in luminosity to 4.5 times that of the Sun, which is being radiated from its outer atmosphere at an effective temperature of 5,068 K. Based upon its estimated orbit, the secondary, component B, has at least times of the Sun's mass. Epsilon Fornacis ε Fornacis (Latinised as Epsilon Fornacis) is the Bayer designation for a high proper"
"the Sun, this star has about half the proportion of elements other than hydrogen and helium. The projected rotational velocity of the star's equator is a relatively leisurely 3.50 km/s. This star has been examined for an infrared excess that could indicate the presence of a circumstellar disk of dust, but as of 2015 none has been detected. The space velocity components of this star are U = −59, V = 20 and W = 4 km/s. It is presently following an orbit through the Milky Way that has an eccentricity of 0.18, bringing it as close as and as"
"4.77 km/s and the major axis of its elliptical orbit is about 39 Astronomical Units (AU) --it travels at a velocity of about 3 miles per second and travels 39 times the distance between the Sun and the Earth at the farthest point from Rukbat in its 250 year orbit. During this time it passes Pern and Rukbat at perihelion and then out through Rukbat's Oort cloud at aphelion (for comparison, our solar system's Oort cloud is considered to start at 50 AU from our sun). More about the nature of the orbital mechanics of Pern, the Red Star and"
"Earth's orbit All celestial bodies in the Solar System, including planets such as our own, orbit around the Solar System's centre of mass. The sun makes up 99.76% of this mass which is why the centre of mass is extremely close to the sun. Earth's orbit is the trajectory along which Earth travels around the Sun. The average distance between the Earth and the Sun is 149.60 million km (92.96 million mi), and one complete orbit takes days (1 sidereal year), during which time Earth has traveled 940 million km (584 million mi). Earth's orbit has an eccentricity of 0.0167."
"2005 HC4 2005 HC is the asteroid with the smallest known perihelion of any known object orbiting the Sun. Its extreme orbital eccentricity brings it to within 0.071 AU of the Sun (23% of Mercury's perihelion) and takes it as far as 3.562 AU from the Sun (well beyond the orbit of Mars). Due to its very small perihelion and comparably large aphelion, 2005 HC4 achieves the fastest speed of any known asteroid bound to the Solar System with a velocity of 157 km/s (565,000 km/h; 351,000 mi/h) at perihelion (there are comets, however, which can obtain much higher speeds)."
"2005 HC4 2005 HC is the asteroid with the smallest known perihelion of any known object orbiting the Sun. Its extreme orbital eccentricity brings it to within 0.071 AU of the Sun (23% of Mercury's perihelion) and takes it as far as 3.562 AU from the Sun (well beyond the orbit of Mars). Due to its very small perihelion and comparably large aphelion, 2005 HC4 achieves the fastest speed of any known asteroid bound to the Solar System with a velocity of 157 km/s (565,000 km/h; 351,000 mi/h) at perihelion (there are comets, however, which can obtain much higher speeds)."
"general vicinity as the Sun. The Sun's orbit around the Milky Way is perturbed due to the non-uniform mass distribution in Milky Way, such as that in and between the galactic spiral arms. It has been argued that the Sun's passage through the higher density spiral arms often coincides with mass extinctions on Earth, perhaps due to increased impact events. It takes the Solar System about 225–250 million years to complete one orbit through the Milky Way (a ""galactic year""), so it is thought to have completed 20–25 orbits during the lifetime of the Sun. The orbital speed of the"
"Earth's sky is to the west at a rate of 15°/h = 15'/min. For bodies near the celestial equator, this is equivalent to an apparent diameter of the Sun or the Moon every two minutes; from Earth's surface, the apparent sizes of the Sun and the Moon are approximately the same. Earth orbits the Sun at an average distance of about every 365.2564 mean solar days, or one sidereal year. This gives an apparent movement of the Sun eastward with respect to the stars at a rate of about 1°/day, which is one apparent Sun or Moon diameter every 12"
"the Sun). By comparison, Neptune orbits at an average distance of 30 AU. The stellar classification for the primary star in this system is G2V; the same as the Sun. That of the red dwarf companion is M4V. The primary star has an estimated 86% to 89% the mass of the Sun, 96% of the Sun's radius, and 85% of the Sun's luminosity. It is a slow rotator, with a projected rotational velocity of 0.5 km/s. Age estimates range from 4.5–5.7 billion years (Gyr) up to 7.1 Gyr or 9.48 Gyr. Compared to the Sun, it only has about 52%"
"the Sun, with an estimated age of six billion years. The star has around 96% of the Sun's radius and 87% of the solar mass. It rotates about the axis an average of once every 13 days, with a projected rotational velocity along the equator of 8 km/s. The abundance of elements other than hydrogen and helium is lower than in the Sun. The effective temperature of the stellar atmosphere is 5,789 K, giving it the yellow hue of a G-type star. An excess of infrared emission at a wavelength of 70 μm suggests the presence of a debris disk."
"had moved over by 2017. The star is moving away from the Earth with an average heliocentric radial velocity of +19.5 km/s. This is an ordinary K-type main-sequence star with a stellar classification of K0 V and no significant variability. The star has 86% of the mass of the Sun and 86% of the Sun's radius. This gives it a bulk density of . It is a chromospherically inactive star and is radiating 56% of the Sun's luminosity from its photosphere at an effective temperature of 5,261 K. The spin of the star displays a relatively low projected rotational velocity"
"and their moons move with the sun. Thus, the solar system is moving. The Earth is rotating or spinning around its axis. This is evidenced by day and night, at the equator the earth has an eastward velocity of . The Earth is also orbiting around the Sun in an orbital revolution. A complete orbit around the sun takes one year, or about 365 days; it averages a speed of about . The Theory of Plate tectonics tells us that the continents are drifting on convection currents within the mantle causing them to move across the surface of the planet"
"the heliosphere at . At this speed, it takes around 1,400 years for the Solar System to travel a distance of 1 light-year, or 8 days to travel 1 AU (astronomical unit). The Solar System is headed in the direction of the zodiacal constellation Scorpius, which follows the ecliptic. The stars and gas in the Milky Way rotate about its center differentially, meaning that the rotation period varies with location. As is typical for spiral galaxies, the orbital speed of most stars in the Milky Way does not depend strongly on their distance from the center. Away from the central"
"the Sun. Around 63 million years old, the star is spinning rapidly with a projected rotational velocity of 185 km/s. It has an estimated 5.9 times the Sun's mass and radiates 1,291 times the solar luminosity from its outer atmosphere at an effective temperature of 16,230 K. \end{align}</math></ref> Delta Fornacis Delta Fornacis, Latinized from δ Fornacis, is a solitary star near the middle of the southern constellation of Fornax. With an apparent visual magnitude of 5.00, it is faintly visible to the naked eye. The star has an annual parallax shift of 3.85 mas, indicating it lies at a distance"
"respect to the local standard of rest, and are the Oort constants, formula_4 is the angular velocity of galactic rotation for the local standard of rest, formula_5 is the ""epicyclic frequency"", and ν is the vertical oscillation frequency. For the sun, the present values of , , and are estimated as formula_6 km/s, and estimates for the other constants are = 15.5 km/s/kpc, = −12.2 km/s/kpc, κ = 37 km/s/kpc, and ν=74 km/s/kpc. We take and to be zero and is estimated to be 17 parsecs. This model implies that the Sun circulates around a point that is itself going"
"mass lifeform extinction periods on Earth. However, a reanalysis of the effects of the Sun's transit through the spiral structure based on CO data has failed to find a correlation. It takes the Solar System about 240 million years to complete one orbit of the Milky Way (a galactic year), so the Sun is thought to have completed 18–20 orbits during its lifetime and 1/1250 of a revolution since the origin of humans. The orbital speed of the Solar System about the center of the Milky Way is approximately or 0.073% of the speed of light. The Sun moves through"
"500 and 1,000 miles per hour,"" according to Edmonds. ""They look like little round planets but they come in all shapes and sizes."" He has asserted that the orbs appear only on digital photographs. In August 2015, Edmonds gave an interview to the ""Daily Mirror"" in which he stated that the greatest problem facing humanity was ""electrosmog"" due to Wi-Fi and other ""systems"", causing the destruction of ""our natural electro-magnetic fields"". He also stated a belief that death was impossible because the body was merely a container for ""a universal energy"", and that this had ""been known for a very"
"would be orbiting in a halo around the Solar System, with orbital periods of millions of years. This halo would lie at between 1,000 and 10,000 AU from the Sun, or between a third and a thirtieth the distance to the Oort cloud. In December 2015, astronomers at the Atacama Large Millimeter Array (ALMA) detected a brief series of 350 GHz pulses that they concluded must either be a series of independent sources, or a single, fast moving source. Deciding that the latter was the most likely, they calculated based on its speed that, were it bound to the Sun,"
"one year. If the Earth orbited the Sun with a constant speed, in a circular orbit in a plane perpendicular to the Earth's axis, then the Sun would culminate every day at exactly the same time, and be a perfect time keeper (except for the very small effect of the slowing rotation of the Earth). But the orbit of the Earth is an ellipse not centered on the Sun, and its speed varies between 30.287 and 29.291 km/s, according to Kepler's laws of planetary motion, and its angular speed also varies, and thus the Sun appears to move faster (relative"
"is following a circular orbit around the Galactic Center at the mean velocity of those nearby stars with low velocity dispersion. The Sun's motion with respect to the LSR is called the ""peculiar solar motion"". The components of space velocity in the Milky Way's Galactic coordinate system are usually designated U, V, and W, given in km/s, with U positive in the direction of the Galactic Center, V positive in the direction of galactic rotation, and W positive in the direction of the North Galactic Pole. The peculiar motion of the Sun with respect to the LSR is with statistical"
"the Earth to the Sun. The primary, component A, has been catalogued with stellar classifications of F3 V and F5 IV, suggesting that it is an F-type star that either belongs to the main sequence or has evolved into a subgiant as the hydrogen at its core nears exhaustion. The primary has an estimated 1.17 times the mass of the Sun and 1.5 times the Sun's radius. It is around 1.5 billion years old and is spinning with a projected rotational velocity of 10 km/s. The star radiates 9.3 times the solar luminosity from its outer atmosphere at an effective"
"absolute magnitude of 10.48, emitting most of its energy in the infrared. Lalande 21185 is a high-proper-motion star moving at about 5 arc seconds a year in an orbit perpendicular to the plane of the Milky Way. The proportion of elements other than hydrogen and helium is estimated based on the ratio of iron to hydrogen in the star when compared to the Sun. The logarithm of this ratio is −0.20, indicating that the proportion of iron is about 10, or 63% of the Sun. The surface gravity of this relatively compact star is approximately 65 times greater than the"
"Earth-crossing orbit. It orbits the Sun at a distance of 1.0–2.8 AU once every 2 years and 7 months (939 days; semi-major axis of 1.88 AU). Its orbit has an eccentricity of 0.48 and an inclination of 13° with respect to the ecliptic. The body's observation arc begins at with its official discovery observation at Catalina Station in December 2014. It passed by Earth on 27 March 2015 at 06:21 UTC at a distance of , or 11.7 lunar distances, and a relative speed of . next encounter with Earth will be in 2033, at a distance of approximately ."