Right Ascension | 11h 41m |
---|---|
Declination | +34° 12' |
Distance | 30.91 ± 0.20 ly |
Spectral Class | G8V |
Estimated Mass | 0.81 × Sol |
Luminosity | 0.57 × Sol |
61 Ursae Majoris as seen from Sol. |
Sol as seen from 61 Ursae Majoris. |
---|---|
Star | Magnitude | Distance |
---|---|---|
Arcturus | −1.12 | 22.4 |
Canopus | −0.53 | 321.6 |
Beta Leonis (Denebola) | −0.18 | 12.3 |
Xi Ursae Majoris (Alula Australis) | 0.07 | 4.9 |
Alpha Aurigae (Capella) | 0.12 | 43.5 |
Rigel | 0.20 | 868.9 |
Betelgeuse | 0.44 | 495.1 |
Regulus | 0.56 | 54.7 |
Beta Centauri (Hadar) | 0.64 | 398.1 |
Pollux | 0.73 | 27.7 |
Alpha Crucis (Acrux) | 0.81 | 327.7 |
Spica | 0.82 | 231.6 |
Vega | 0.82 | 36.1 |
Achernar | 0.85 | 167.3 |
Epsilon Ursae Majoris (Alioth) | 0.91 | 55.8 |
61 Ursae Majoris is a sunlike star with a spectral type of G8V that is located 30.9 light years from Sol. This star is slightly less massive than Sol, and has a luminosity slightly greater than half that of the Sun.
Destination | Distance |
---|---|
Chara | 7.5 |
Groombridge 1618 | 17.8 |
Probes from the Dandelion Project explored the system for the first time in 3006. The system has six planets, some of which have markedly eccentric orbits.
Planet | SMA (AU) |
Orbital Period |
e | Equatorial Diameter (km) |
Mass (Earths) |
Density (g/cm3) |
Gravity (Earth g) |
Atmospheric Pressure (Earth=1) |
Sidereal Day |
Mean Solar Day |
Axial Tilt |
Known Moons |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Garumna | 0.1285 | 18.699 d | 0.0027 | 3623 | 0.01773 | 4.25 | 0.2197 | &mdash | 18d 16h 46.8m | Synchronous | 00° 17.0' | 0 |
Sequana | 0.2526 | 51.515 d | 0.0845 | 5237 | 0.05648 | 4.49 | 0.3349 | &mdash | 51d 12h 21.8m | Synchronous | 00° 29.7' | 0 |
Samara | 0.8649 | 309.07 d | 0.1840 | 11330 | 0.6640 | 5.23 | 0.8414 | 0.895 | 1d 04h 18.1m | 1d 04h 24.6m | 02° 56.6' | 2 |
Tiberis | 2.315 | 3.9145 y | 0.0859 | 7542 | 0.1588 | 4.22 | 0.4540 | &mdash | 17h 56.3m | 17h 56.9m | 11° 56.7' | 1 |
Padus | 7.129 | 21.150 y | 0.0744 | 58570 | 30.66 | 1.78 | 1.453 | &mdash | 14h 45.9m | 14h 46.0m | 16° 18.3' | 6 |
Danuvius | 30.88 | 190.70 y | 0.4830 | 138900 | 233.5 | 1.07 | 1.968 | &mdash | 13h 20.7m | 13h 20.7m | 16° 18.3' | 10 |
Name | Diameter (km) |
Period (days) |
Semimajor Axis (km) |
Ecc | Inc |
---|---|---|---|---|---|
Natural Satellites of Samara | |||||
Selle | 418 | 5.115 | 109400 | 0.0124 | 0.37 |
Avre | 95 | 21.08 | 281200 | 0.0937 | 3.24 |
Natural Satellites of Tiberis | |||||
Anio | 26 | 1.025 | 23260 | 0.2035 | 0.00 |
Natural Satellites of Padus | |||||
Secia | 124 | 0.6299 | 52180 | 0.0009 | 0.02 |
Trebia | 154 | 1.847 | 104800 | 0.0185 | 0.25 |
Ticinus | 1702 | 2.463 | 127000 | 0.0108 | 0.27 |
Orgus | 132 | 3.286 | 153900 | 0.0260 | 0.45 |
Tanarus | 662 | 4.928 | 201600 | 0.0387 | 1.44 |
Addua | 1830 | 14.67 | 417200 | 0.0023 | 0.17 |
Natural Satellites of Danuvius | |||||
Regen | 86 | 0.7413 | 213100 | 0.0007 | 0.05 |
Arabo | 1403 | 1.117 | 280100 | 0.0028 | 0.35 |
Oenus | 2169 | 1.677 | 367200 | 0.0020 | 0.32 |
Ilz | 83 | 1.677 | 367200 | 0.0020 | 0.23 |
Anisus | 1707 | 2.789 | 515400 | 0.0045 | 0.48 |
Isarus | 222 | 6.502 | 906200 | 0.1039 | 1.30 |
Tisia | 6566 | 9.753 | 1188000 | 0.0018 | 0.25 |
Ilargus | 158 | 14.63 | 1556000 | 0.1186 | 1.56 |
Moravia | 1292 | 24.43 | 2190000 | 0.0701 | 0.80 |
Licca | 572 | 52.61 | 3652000 | 0.0886 | 4.51 |
Garumna is a heavily cratered planet slightly smaller than Mercury. The world lacks an appreciable atmosphere and is geologically inert.
Sequana is a small planet roughly the size of Mercury. Like Garumna, it is heavily cratered and lacks an appreciable atmosphere.
Samara is an ice-covered Earth-sized world with an eccentric orbit and a low axial tilt. The high eccentricity and low axial tilt combine to make the world the only potentially habitable world within ten parsecs of Sol where the primary driving force behind the seasons is the eccentricity of the orbit instead of the tilt of the axis.
The axial tilt of Samara is low enough that the larger moon of Selle transits the local sun on every orbit. Consequently, the day length on Samara varies little over the course of a year, even at high latitudes.
The eccentricity of the orbit causes the time of sunrise on Samara to vary by about of a day. The latest sunrises and sunsets occur when Samara is halfway between periastron and apastron, the equivalent of the end of the global summer.
Tiberus is a world slightly larger than Mars with a similar climate.
Padus is a blue gas giant with a mass about twice that of Neptune.
Danuvius is the largest planet in the 61 Ursae Majoris system with a mass slightly less than three-quarters of that of Jupiter. It is a bluish world, with its cloud features mainly shaped by internal heat.
Its orbit is unusual for such a large planet, being markedly eccentric with an eccentricity of about 0.5. The high eccentricity causes the planet to vary considerably in brightness as seen from Samara over the course of its orbit. When at periastron, it is a moderately bright planet at opposition as seen from Samara with a magnitude of about 2.5, but near apastron it fades to the invisibility of magnitude 7.