Struve 2398 ABC

Star type
g A: M3.0V
g B: M3.4V
g C: M6Ve

Distance from Earth
g 11.64 ly

Star Service No.
g NA

Age
g A: NA
g B: NA
g C: NA

Diameter/Mass/Temp (xSol)
g A: 55%; 30%; 3070 F
g B: 54%; 36%; 2940 F
g C: NA; 13%; NA

Brightness (xSol)
g A: 27/10000th
g B: 13/10,000th
g C: 0.13%

Metallicity
g A: NA
g B: NA
g C: NA

Comparison to Sol
g A: NA
g B: NA
g C: NA

Picture of star
g Struve 2398 AB shown at upper right (courtesy ESO Online Digitized Sky Survey)

Star system features
g Struve 2398 A and B, that orbit each other at an "average" period of 408 years with an eccentricity of 0.53, and an average distance of 56 AUs where the pair swings between 26 and 86 AUs apart

Known planets
g A: A recent search for faint companions using the Hubble Space Telescope found no supporting evidence for a large Jupiter or brown dwarf sized object
g B: A recent search for faint companions using the Hubble Space Telescope found no supporting evidence for a large Jupiter or brown dwarf sized object
g C: NA

Habitable zone
g A: Accounting for infrared heating, the distance from Struve 2398 A where an Earth-type planet would be "comfortable" with liquid water is centered around only 0.17 AU. At that distance from the star, such a planet would have an orbital period of around 98 days, and so it may become tidally locked in orbit so that one side stays in perpetual daylight while the other lies in darkness
g B: Accounting for infrared heating, the distance from Struve 2398 B where an Earth-type planet would be "comfortable" with liquid water is centered around only 0.15 AU. At that distance from the star, such a planet would have an orbital period of only around 39 days and so would likely be tidally locked with perpetual daylight on one side.
g C: NA

Orbital map
g See orbital map

View from star
g NA

Nearby stars
(Star systems with 10 light years)
g BD+68 946 AB, 4.2 ly
g V1581 Cygni AB, 5.8 ly
g 61 Cygni AB, 6.1 ly
g Kruger 60 AB: 6.2 ly
g Sigma Draconis, 7.9 ly
g LP 44-113, 9.2 ly
g Barnard's Star, 9.5 ly
g Hip 85605, 9.8 ly
g Groombridge 34 Aab,B, 9.9 ly

Map locating star system
g NA

Location in Earth sky
g In northeastern part in Constellation Draco, the Dragon - northeast of Grumium (Xi Draconis) and southwest of Altais or Nodus Secundus (Delta Draconis); too dim to be seen with the naked eye

Other names
g A-B: Sigma 2398
g A-B: LP 299-30
g A: NSV 11288
g A: ADS 11632
g A: Gl 725 A
g A: Hip 91768
g A: HD 173739
g A: BD+59 1915 A
g A: SAO 31128
g A: G 227-46
g A: G 229-13
g A: LHS 58
g A: LTT 15522
g A: LDS 1466
g A: LFT 1431
g B: Gl 725 B
g B: Hip 91772
g B: HD 173740
g B: BD+59 1915 B
g B: SAO 31129
g B: G 227-47
g B: LHS 59
g C: YZ Ceti
g C: Gl 54.1
g C: LTT 670
g C: L 725-32

Sci-fi mentions
g NA

Get your SF book manuscript edited