47 Ursae Majoris (abbreviated 47 UMa) is a 5th magnitude yellow dwarf star in the constellation of Ursa Major. Its spectral type, G1 V, is similar to our Sun. The star is relatively nearby, distance being only 44 light years. It is visible to the unaided eye under good conditions. In astronomy, an epoch is a moment in time for which celestial coordinates or orbital elements are specified. ... 2000 is a leap year starting on Saturday of the Gregorian calendar. ... Orion is a remarkable constellation, visible from most places on the globe (but not always the whole year long). ... Ursa Major is a constellation visible throughout the year in the northern hemisphere. ... Right ascension (RA; symbol α: Greek letter alpha) is the astronomical term for one of the two coordinates of a point on the celestial sphere when using the equatorial coordinate system. ... In astronomy declination (dec) is one of the two coordinates of the equatorial coordinate system, the other being either right ascension or hour angle. ... A light year, abbreviated ly, is the distance light travels in one year: roughly 9. ... This article is about the unit of length. ... In astronomy, stellar classification is a classification of stars based initially on photospheric temperature and its associated spectral characteristics, and subsequenly refined in terms of other characteristics. ... The apparent magnitude (m) of a star, planet or other heavenly body is a measure of its apparent brightness; that is, the amount of light received from the object. ... The apparent magnitude (m) of a star, planet or other heavenly body is a measure of its apparent brightness; that is, the amount of light received from the object. ... Categories: Astronomy stubs | Yellow dwarfs ... The Pleiades star cluster A star is any massive gaseous body in outer space just like the Sun. ... Orion is a remarkable constellation, visible from most places on the globe (but not always the whole year long). ... Ursa Major is a constellation visible throughout the year in the northern hemisphere. ... In astronomy, stellar classification is a classification of stars based initially on photospheric temperature and its associated spectral characteristics, and subsequenly refined in terms of other characteristics. ... A Sun is the star at the centre of a solar system. ... A light year, abbreviated ly, is the distance light travels in one year: roughly 9. ...

It was one of the first stars known to possess extrasolar planets. It currently has two known planets, designated as 47 Ursae Majoris b and c. Infrared Image of a possible extrasolar planet (lower left) in the Constellation Taurus, taken by the Hubble Space Telescope. ...

47 Ursae Majoris b

After the discovery of the first extrasolar planet around a Sun-like star, 51 Pegasi b, astronomers Geoffrey Marcy and Paul Butler searched through their observational data for extrasolar planets and soon discovered two, 47 Ursae Majoris b and 70 Virginis b. Had they known that many planets orbit close their parent stars, they would have been the first extrasolar planet discoverers. In geometry, the semi-major axis (also semimajor axis) a applies to ellipses and hyperbolas. ... The astronomical unit (AU or au or a. ... (This page refers to eccitricity in astrodynamics. ... The orbital period is the time it takes a planet (or another object) to make one full orbit. ... A year is the time between two recurrences of an event related to the orbit of the Earth around the Sun. ... A day is any of several different units of time. ... Inclination is one of the six orbital parameters describing the shape and orientation of a celestial orbit and is the angular distance of the orbital plane from the plane of the reference (usually planets equator or the ecliptic), stated in degrees. ... This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ... This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ... The Julian day or Julian day number (JDN) is the number of days that have elapsed since 12 noon Greenwich Mean Time (UT or TT) on Monday, January 1, 4713 BC (in the proleptic Julian calendar; or November 24, 4714 BC in the proleptic Gregorian calendar). ... Mass is a property of physical objects that, roughly speaking, measures the amount of matter they contain. ... Atmospheric characteristics Atmospheric pressure 70 kPa Hydrogen ~86% Helium ~14% Methane 0. ... The word radius (Latin for wheel spoke; plural radii, pronounced ray-dee-eye) has several meanings in English: In classical geometry, a radius of a circle or sphere is any line segment with one endpoint on the circle (i. ... Density (symbol: ρ - Greek: rho) is a measure of mass per unit of volume. ... The international prototype, made of platinum-iridium, which is kept at the BIPM under conditions specified by the 1st CGPM in 1889. ... The cubic metre (symbol m³) is the SI derived unit of volume. ... Temperature is the physical property of a system which underlies the common notions of hot and cold; the material with the higher temperature is said to be hotter. ... The kelvin (symbol: K) is the SI unit of temperature, and is one of the seven SI base units. ... Categories: Astronomers stubs | Astronomers ... Categories: American astronomers | Astronomers stubs ... 1996 is a leap year starting on Monday of the Gregorian calendar, and was designated the International Year for the Eradication of Poverty. ... Bellerophon is the first planet discovered around a sun-like star outside of the solar system. ... Categories: American astronomers | Astronomers stubs ... Categories: Astronomers stubs | Astronomers ... 70 Virginis is a main sequence star in the constellation Virgo with a confirmed extrasolar planet, at least 6. ...

But 47 Ursae Majoris b is different. Like others, it is a massive gas giant, being about 2.5 times as massive as Jupiter. However, its distance from the star is larger than most, little more than that of Mars from our Sun. And, unlike the "eccentric Jupiters", the orbit of the planet is almost circular as is the case with the giant planets in our Solar system. A gas giant is a large planet that is not composed mostly of rock or other solid matter. ... Atmospheric characteristics Atmospheric pressure 70 kPa Hydrogen ~86% Helium ~14% Methane 0. ... Mars is the fourth planet from the Sun in the solar system, named after the Roman god of war (the counterpart of the Greek Ares), on account of its blood red color as viewed in the night sky. ... (This page refers to eccitricity in astrodynamics. ... A gas giant is a large planet that is not composed mostly of rock or other solid matter. ... Mosaic of the planets of the solar system, excluding Pluto, and including Earths Moon. ...

Unfortunately, the moons of the planet, if it has any, are likely too cold to support any life unless they have subsurface oceans like Jupiter's moon Europa. On the other hand, the planet is still too close to its parent star as its gravitational influence may have prevented formation of any Earth-like planets in the system. Atmospheric characteristics Atmospheric pressure 1 µPa Oxygen 100% Europa (yew-roh-pa, Greek Ευρώπη) is a moon of the planet Jupiter, smallest of the four Galilean moons. ... This article covers the physics of gravitation. ... Earth, also known as the Earth or Terra, is the third planet outward from the Sun. ...

47 Ursae Majoris c

The second planet, 47 Ursae Majoris c, orbits further out than planet b, about the distance of the outer asteroid belt in our Solar system. It is slightly less massive than Jupiter, and it too has a fairly circular orbit. In geometry, the semi-major axis (also semimajor axis) a applies to ellipses and hyperbolas. ... The astronomical unit (AU or au or a. ... (This page refers to eccitricity in astrodynamics. ... The orbital period is the time it takes a planet (or another object) to make one full orbit. ... A year is the time between two recurrences of an event related to the orbit of the Earth around the Sun. ... A day is any of several different units of time. ... Inclination is one of the six orbital parameters describing the shape and orientation of a celestial orbit and is the angular distance of the orbital plane from the plane of the reference (usually planets equator or the ecliptic), stated in degrees. ... This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ... This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ... The Julian day or Julian day number (JDN) is the number of days that have elapsed since 12 noon Greenwich Mean Time (UT or TT) on Monday, January 1, 4713 BC (in the proleptic Julian calendar; or November 24, 4714 BC in the proleptic Gregorian calendar). ... Mass is a property of physical objects that, roughly speaking, measures the amount of matter they contain. ... Atmospheric characteristics Atmospheric pressure 70 kPa Hydrogen ~86% Helium ~14% Methane 0. ... The word radius (Latin for wheel spoke; plural radii, pronounced ray-dee-eye) has several meanings in English: In classical geometry, a radius of a circle or sphere is any line segment with one endpoint on the circle (i. ... Density (symbol: ρ - Greek: rho) is a measure of mass per unit of volume. ... The international prototype, made of platinum-iridium, which is kept at the BIPM under conditions specified by the 1st CGPM in 1889. ... The cubic metre (symbol m³) is the SI derived unit of volume. ... Temperature is the physical property of a system which underlies the common notions of hot and cold; the material with the higher temperature is said to be hotter. ... The kelvin (symbol: K) is the SI unit of temperature, and is one of the seven SI base units. ... Professor Fischer showing off her pgplot prowess with a keplerian fit for υ And. ... Categories: Astronomers stubs | Astronomers ... Categories: American astronomers | Astronomers stubs ... 2002 is a common year starting on Tuesday of the Gregorian calendar. ... The asteroid belt is a region of the solar system falling roughly between the planets Mars and Jupiter where the greatest concentration of asteroid orbits can be found. ...

The planetary system of 47 Ursae Majoris shares other similarities with our Solar system, too: the ratio between the masses of b and c is 3.34 (3.32 between Jupiter and Saturn), and the ratio between orbital distances of the planets is 0.560 (0.545). Whether this is just coincidence or has any deeper meaning has not yet been figured out. Atmospheric characteristics Atmospheric pressure 140 kPa Hydrogen >93% Helium >5% Methane 0. ...

References

• " HD 95128 (http://simbad.u-strasbg.fr/sim-id.pl?protocol=html&Ident=HD+95128)." SIMBAD. Accessed on April 17, 2005.
• " 47 UMA B (http://simbad.u-strasbg.fr/sim-id.pl?protocol=html&Ident=47+UMA+B)." SIMBAD. Accessed on April 17, 2005.
• " 47 UMA C (http://simbad.u-strasbg.fr/sim-id.pl?protocol=html&Ident=47+UMA+C)." SIMBAD. Accessed on April 17, 2005.
• "Notes for 47 UMa (http://www.obspm.fr/encycl/47Uma.html)." The Extrasolar Planets Encyclopaedia. Accessed on April 17, 2005.

April 17 is the 107th day of the year in the Gregorian calendar (108th in leap years). ... 2005 is a common year starting on Saturday of the Gregorian calendar. ... April 17 is the 107th day of the year in the Gregorian calendar (108th in leap years). ... 2005 is a common year starting on Saturday of the Gregorian calendar. ... April 17 is the 107th day of the year in the Gregorian calendar (108th in leap years). ... 2005 is a common year starting on Saturday of the Gregorian calendar. ... April 17 is the 107th day of the year in the Gregorian calendar (108th in leap years). ... 2005 is a common year starting on Saturday of the Gregorian calendar. ...

External links

• Extrasolar Visions entry (http://www.extrasolar.net/startour.asp?StarCatID=normal&StarID=7)
• The Encyclopedia of the Suns entry (http://www.astronexus.com/scripts/eos/eos_star.php?IDType=HD&ID=95128)