《史诗战争模拟》游侠LMAO汉化补丁下载发布！
 Enhanced-color view of Phobos obtained by Mars Reconnaissance Orbiter on March 23 2008. | |
| Discovery | |
|---|---|
| Discovered by | Asaph Hall |
| Discovery date | August 18, 1877 |
| Orbital characteristics | |
| Epoch J2000 | |
| Periapsis | 9235.6 km |
| Apoapsis | 9518.8 km |
| 9377.2 km[1] | |
| Eccentricity | 0.0151 |
| 0.31891023 d (7 h 39.2 min) | |
Average orbital speed | 2.138 km/s |
| Inclination | 1.093° (to Mars's equator) 0.046° (to local Laplace plane) 26.04° (to the ecliptic) |
| Satellite of | Mars |
| Physical characteristics | |
| Dimensions | 26.8 × 22.4 × 18.4 km[2] |
Mean radius | 11.1 km[3] (0.0021 Earths) |
| ~6100 km2 (11.9 μEarths) | |
| Volume | 5680 km3[4] (5.0 nEarths) |
| Mass | 1.072×1016 kg[5] (1.8 nEarths) |
Mean density | 1.887 g/cm3[4] |
| 0.0084–0.0019 m/s2 (8.4-1.9 mm/s2) (860-190 μg) | |
| 11.3 m/s (40 km/h)[5] | |
| synchronous | |
Equatorial rotation velocity | 11.0 km/h (at longest axis' tips) |
| 0° | |
| Albedo | 0.071[3] |
| Temperature | ~233 K |
| 11.3[6] | |
Phobos (or Mars I) is one of Mars' moons. The other is Deimos.
Phobos is the larger of the two moons, and is only 27 kilometers in diameter. This is about as far as a car can travel on the highway in 15 minutes. It is covered with craters, as Earth's moon is.[7]
It is named after the god Phobos in Greek mythology. Its name means "fear".
Phobos is trapped in tidal drag, with its orbit lowering roughly 1.8 meters per century. In about 50 million years, Phobos will reach the Roche limit, where it is likely to be torn apart. Some fragments will fall on Mars and some will form a planetary ring or rings around Mars.
The other moon, Deimos, is the smaller of the two.
Spacecraft
[change | change source]The Soviet Union sent at least two space craft to this moon, Phobos 1 and Phobos 2. Both failed or lost contact with Earth, but Phobos 2 managed to take some pictures of the moon in 1989 before dying.
Features
[change | change source]There is one large crater on Phobos called Stickney. It is the size of the moon itself.
References
[change | change source]- ↑ "NASA Celestia". Archived from the original on 2025-08-06. Retrieved 2025-08-06.
- ↑ "Mars: Moons: Phobos". NASA Solar System Exploration. 2025-08-06. Archived from the original on 2025-08-06. Retrieved 2025-08-06.
- ↑ 3.0 3.1 "Planetary Satellite Physical Parameters". JPL (Solar System Dynamics). 2025-08-06. Retrieved 2025-08-06.
- ↑ 4.0 4.1 "Mars Express closes in on the origin of Mars' larger moon". DLR. 2025-08-06. Archived from the original on 2025-08-06. Retrieved 2025-08-06.
- ↑ 5.0 5.1 use a spherical radius of 11.1 km; volume of a sphere * density of 1.877 g/cm3 yields a mass (m=d*v) of 1.07×1016 kg and an escape velocity (sqrt((2*g*m)/r)) of 11.3 m/s (40 km/h)
- ↑ "Classic Satellites of the Solar System". Observatorio ARVAL. Archived from the original on 2025-08-06. Retrieved 2025-08-06.
- ↑ Gater, Will (2009). Space 3D. Bristol Magazines. p. 67.
