Facts about Phobos's Orbit Decay
- 09
Each Martian day, Phobos spirals 1.8 centimeters closer to Mars due to tidal dissipation, meaning the moon's distance shrinks by roughly 65.7 meters over a single human century.
- 08
By 100 million years from now, Phobos will have spiraled so close to Mars that it enters the planet's atmosphere, experiencing ablation and breakup at approximately 70 kilometers altitude.
- 07
Current measurements indicate Phobos orbits Mars every 7 hours and 39 minutes, a period that accelerates by approximately 0.1319 seconds per century due to orbital decay.
- 06
Astronomers estimate Phobos completes one additional orbit around Mars every 11,000 years due to orbital decay, meaning the moon's year-length grows progressively shorter.
- 05
Roche's limit calculations suggest Phobos will fragment into debris when it reaches approximately 11,500 kilometers from Mars's center, roughly 2.3 times closer than its current orbital distance.
- 04
Phobos's orbital period shortens by approximately 0.1319 seconds per century as gravitational drag inexorably pulls the Martian moon toward the planet's surface.
- 03
Tidal heating from Mars's gravity generates enough internal friction within Phobos to gradually circularize its orbit while simultaneously lowering its altitude across millions of years.
- 02
Within 30 to 50 million years, Phobos will either disintegrate into a ring system around Mars or impact the planet's surface due to accumulated orbital decay from gravitational tidal forces.
- 01
Mars's moon Phobos loses approximately 1.8 centimeters of orbital altitude annually due to tidal friction, ultimately destined to collide with Mars in roughly 30 to 50 million years.