Groombridge 1830

Groombridge 1830
 * Union System - Former United Earth system
 * M-0 Galaxy, Upward Sector -
 * Distance to Sol : 29.9 LY
 * Spectral type G8VIp -
 * UAS: Argelander's Star  (Commonly called Argelanders)

5 Planets, 11 Dwarf Planets, 122 larger moons Asteroid belt

First surveyed in 2112 OTT. While the system has an abundance of celestial real estate, the frequent an d violent super flare activity of the star does not allow for carbon based life development. No native life has been found and while one of the rock planets is within the liquid water zone, it has no water and is exposed to  thermal shocks and hard radioation.

The super flares are caused by jovian planet in the first orbit of the system.

The planets are

 * Enticer, Jovian
 * Magister, Jovian
 * Blue Light, Rock
 * Pink Clouds Sub Jovian
 * Sheen, Ice planet

The abundance of raw materials and short distance to the Sol system was reason enough for the first colonists to arrive on planet Blue Light in 2142 OTT. At first mining oprations sprung up all over the system. Then ore processing and smelting operations followed.

The system today has still many mining operations and is a heavy industrialized system focusing on metal and mineral production. Copper, massive  amounts of iron ore, and bauxite. Nonmetallic mined minerals include salt, limestone, sulfur,, dolomite, barite, feldspar and rare earths.

Besides a Class A space port, there is the largest Ore transfer port in the Union. Port Ferrum is legendary in every aspect.

The XChange on Sheen is the largest metal ore and raw ingot trading market within the Union. (Makign deals all across the Union)

89 Billion  live and work in the system, and additional 20 million commute from other systems via space trains, teams and since 5048 viam long range TMT from Sol Hub.

System Summary

Groombridge 1830 is located about 29.9 light-years (ly) from our Sun, Sol. It lies in the southern part (11:52:58.77+37:43:07.24, ICRS 2000.0) of Constellation Ursa Major, the Great Bear, which also encompasses the Big Dipper -- northeast of Alula Borealis (Nu Ursae Majoris) and Alula Australis (Xi or Ksi Ursae Majoris). This star was listed by Stephen Groombridge (1755-1834), whose "A Catalog of Circumpolar Stars, Reduced to January 1, 1810" [see page 54] was published posthumously in 1838. In 1842, Friedrich Wilhelm August Argelander (1799-1875) noted its exceptionally large proper motion -- now the third highest after Barnard's and Kapteyn's stars (Wulff Dieter Heintz, 1984). Argelander published a catalog in 1863 on the position and brightness of 324,198 stars between +90° and -2° declination that were measured over 11 years from Bonn, Germany with his assistants Eduard Schönfeld (1828-1891) and Aldalbert Krüger (1832-1896), which became famous as the Bonner Durchmusterung ("Bonn Survey") abbreviated as BD and was greatly expanded and extended into the 20th Century with the Cordoba then the Cape Photographic Durchmusterung from South Africa.

The Star

Unusually faint for its spectral type, Groombridge 1830 is a yellow-orange halo subdwarf star of spectral and luminosity type sdG8p /VI. The star may have about sixth tenths of Sol's mass (Smith et al, 1992), 64 percent of its diameter, but only 19 percent of its luminosity. It may only be about three to 10 percent as enriched as Sol in elements heavier than hydrogen (Cayrel de Strobel et al, 1991, page 20; and J. Tomkin, 1972). As a G8, it is sufficiently cool not to have evolved appreciably despite a high probable age. The star is at least 5.4 billion years old based on chromospheric anaysis alone (Don C. Barry, 1998, page 3), but its halo subdwarf status would suggest that the star is at least 10 billion years old, having formed during a period of rapid collapse that lasted perhaps a billion years in the early history of the Milky Way galaxy prior the development of the galactic disk. It has the New Suspected Variable designation NSV 5374. Some useful catalogue numbers for this star are: HR 4550, Gl 451 A, Hip 57939, HD 103095, BD+38 2285, SAO 62738, FK5 1307, G 122-51, G 148-18, LHS 44, LTT 13276, LFT 855, and Gmb 1830.

In 1968, Peter van de Kamp (1901-1995) at Sproul Observatory detected a flare from what was presumed to be a dim companion that was two magnitudes fainter than the primary. Although there were later observations of flares, the faint companion did not appear on many other photographic plates, and it was presumed to be a rapid variable such as a flare star and given the variable star designation CF Ursae Majoris sometime after 1980. However, no changes in radial velocity were detected between 1974 and 1984 to confirm possible variations found around 1920 (R. F. Griffin, 1984; and Beardsley et al, 1974). Moreover, subsequent astrometric measurements were negative (Heintz, 1984), as were infrared speckle interferometric observations (ARICNS note). New observations announced in 1998 suggest that sightings of the "companion" were actually observations of a new gargantuan class of stellar mass ejection associated recently with Sol-type stars of spectral class F8 to G8 called a "superflare" from the primary star itself (Schaefer et al, 2000).

Given the regular eruption of superflares, it is unlikely that Earth-type life could survive for long on any inner rocky planet. The distance from either Groombridge 1830 where an Earth-type planet would be comfortable with liquid water is only about 0.44 AU (around the orbit of Mercury), but at that distance, such a planet would be very difficult to detect using present methods. Given the low abundance of elements heavier than hydrogen, moreover, it is possible that the star is more likely to have gas giants in cold outer orbits.

Super Flares

According to one recent hypothesis, unusually intense stellar flares from a sun-like ("Sol-type") star could be caused by the interaction of the magnetic field of a giant planet in tight orbit with that star's own magnetic field (Rubenstein and Schaefer, 2000). Some Sol-type stars of spectral class F8 to G8 have been found have been observed to undergo enormous magnetic outbursts to produce "superflares" (coronal mass ejections) that release between 100 and 10 million times more energy than the largest flares ever observed on the sun, making them brighten briefly by up to 20 times. These superflares last from one hour to one week and increase the normal luminosity of a star as much as one thousand times. If our sun were to produce a large superflare, Earth's ozone layer would be destroyed, and ice on the daylight side of moons as far out as those of Jupiter or even Saturn would be melted, producing vast floodplains that refreeze after the flare subsides. No traces of past superflares have been detected in our Solar System.

It is a yellow-hued class G8 subdwarf catalogued by Stephen Groombridge with the Groombridge Transit Circle between 1806 and the 1830s and published posthumously in his star catalog, Catalogue of Circumpolar Stars (1838). Its high proper motion was noted by Friedrich Wilhelm Argelander in 1842.

It is 29.9 light-years (9.2 parsecs) from the Sun as measured by the Hipparcos astrometry satellite,which, as the distance is nearly 10 parsecs, means its absolute magnitude is almost equal to its apparent magnitude. It is a member of the galactic halo; such stars account for only 0.1 to 0.2 percent of the stars near the Sun. Like most halo stars, it has a low abundance of elements other than hydrogen and helium—what astronomers term a metal-poor star.


 * halo stars like Groombridge 1830 do not follow this galaxy rotation and thus are "standing still" and appear to be moving in "retrograde direction" at high speed.

Once suspected of being a binary star with a period of 175 days, current consensus is that it is single. Previous suspected observations of a stellar companion were probably "superflares"—analogous to the Sun's solar flares, but hundreds to millions of times more energetic.[12][13]