فوبوس (قمر)

فوبوس
Phobos
	Enhanced-color view of Phobos obtained by Mars Reconnaissance Orbiter on March 23, 2008.
الاكتشاف
اكتشفه	أساف هول
تاريخ الاكتشاف	18 أغسطس، 1877
التسميات
الأسماء البديلة	المريخ 1
الصفات	Phobian
السمات المدارية
	حقبة J2000
Periapsis	9,235.6 kم (30,301,000 قدم)
Apoapsis	9,518.8 kم (31,230,000 قدم)
Semi-major axis	9,377.2 kم (30,765,000 قدم)
Eccentricity	0.0151
Orbital period	0.31891023 d; (7 h 39.2 min)
Average orbital speed	2.138 كم/ث (1.328 ميل/ث)
Inclination	1.093° (to Mars's equator); 0.046° (to local Laplace plane); 26.04° (to the ecliptic)
Satellite of	Mars
السمات الطبيعية
الأبعاد	26.8 × 22.4 × 18.4 kم (60,000 قدم)
نصف القطر المتوسط	11.1 kم (36,000 قدم); (0.0021 Earths)
Mean radius	11.1 kم (36,000 قدم); (0.0021 Earths)
Surface area	~6,100 kم2 (6.6×1010 قدم2); (11.9 µEarths)
Volume	5,680 kم3 (2.01×1014 قدم3); (5.0 nEarths)
Mass	1.072×1016 kg; (1.8 nEarths)
Mean density	1.876 g/cm³
Surface gravity	0.0084–0.0019 m/s²; (8.4-1.9 mm/s²); (860-190 µg)
Escape velocity	11.3 m/s (40 km/h)
Rotation period	synchronous
Equatorial rotation velocity	11.0 كم/س (6.8 ميل/س) (at longest axis' tips)
Axial tilt	0°
Albedo	0.071
Temperature	~233 K
Apparent magnitude	11.3

فوبوس Phobos (تـُنطـَق /ˈfoʊbəs/ ، باليونانية Φόβος) (systematic designation: Mars I)أكبر وأقرب أقمار المريخ, والقمر الثاني هوديموس. وقد تم اكتشافهما عام 1877. ويبلغ متوسط نصف قطر فوبوس 11.1 kم (6.9 ميل)، وتصل كتلته إلى 7.24 ضعف كتلة ديموس. وسمي على اسم الإله اليوناني فوبوس (ويعني "الخوف"), ابن أريس (المريخ).

الاكتشاف

الخصائص الفيزيائية

A mosaic of three separate images taken by Viking 1 on October 19, 1978. The large crater (mostly in darkness) on the upper left is Stickney.

"Hollow Phobos" suggestions

خصائص جيولوجية مسماة

الحفر البركانية	التسمية	الاحداثيات
Clustril	Character in Gulliver's Travels
D'Arrest	Heinrich Louis d'Arrest, astronomer
Drunlo	Character in Gulliver's Travels
Flimnap	Character in Gulliver's Travels
Grildrig	Character in Gulliver's Travels
Gulliver	Main character of Gulliver's Travels
Hall	Asaph Hall, discoverer of Phobos
Limtoc	Character in Gulliver's Travels
Reldresal	Character in Gulliver's Travels
Roche	Édouard Roche, astronomer
Sharpless	Bevan Sharpless, astronomer
Skyresh	Character in Gulliver's Travels
Stickney	Angeline Stickney, wife of Asaph Hall
Todd	David Peck Todd, astronomer
Wendell	Oliver Wendell, astronomer

الخصائص المدارية

Orbits of Phobos and Deimos (to scale), seen from above Mars' north pole. Phobos is orbiting Mars 3.96 times faster than Deimos.

Phobos transits Sun, as seen by Mars Rover Opportunity

=العبور الشمسي

الفناء المستقبلي

المنشأ

Viking 1 image of Phobos, with Stickney Crater to the right

الاستكشاف

The Phobos monolith (right of center) as taken by the Mars Global Surveyor (MOC Image 55103) in 1998.

مهمات مستقبلية

انظر أيضا

فوبوس وديموس في الخيال
مهمة فوبوس-گرونت
عبور فوبوس من المريخ

المصادر

^ NASA Celestia
^ "Mars: Moons: Phobos". NASA Solar System Exploration. September 30, 2003. Retrieved August 18, 2008.
^ "Planetary Satellite Physical Parameters". JPL (Solar System Dynamics). July 13, 2006. Retrieved January 29, 2008.
^ "Mars Express closes in on the origin of Mars' larger moon". DLR. October 16, 2008. Retrieved October 16, 2008.
^ use a spherical radius of 11.1 kم (36,000 قدم); 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)
^ "Precise mass determination and the nature of Phobos". Geophysical Research Letters, Vol. 37. Retrieved May 31, 2010.
^ "Classic Satellites of the Solar System". Observatorio ARVAL. Retrieved September 28, 2007.

وصلات خارجية

Phobos Profile at NASA's Solar System Exploration site
HiRISE images of Phobos
USGS Phobos nomenclature
Asaph Hall and the Moons of Mars
Flight around Phobos (movie)
Animation of Phobos

[1] NASA Celestia

[NASA-2] "Mars: Moons: Phobos". NASA Solar System Exploration. September 30, 2003. Retrieved August 18, 2008.

[jplssd-3] "Planetary Satellite Physical Parameters". JPL (Solar System Dynamics). July 13, 2006. Retrieved January 29, 2008.

[dlr2008-4] "Mars Express closes in on the origin of Mars' larger moon". DLR. October 16, 2008. Retrieved October 16, 2008.

[estimate-5] use a spherical radius of 11.1 kم (36,000 قدم); 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)

[grl2010-6] "Precise mass determination and the nature of Phobos". Geophysical Research Letters, Vol. 37. Retrieved May 31, 2010.

[magnitude-7] "Classic Satellites of the Solar System". Observatorio ARVAL. Retrieved September 28, 2007.