Irregularly Shaped Satellites-Phobos & Deimos- moons of Mars, and their evolutionary history

TL;DR

This paper analyzes the orbital decay of Mars's moons Phobos and Deimos, proposing a new age estimate for Phobos based on planetary-satellite dynamics, predicting its eventual collision with Mars in about 10 million years.

Contribution

The study introduces a revised method for estimating Phobos's age using detailed satellite dynamics, challenging previous altitude loss estimates and providing a new timeline for its destruction.

Findings

Phobos's age is estimated at approximately 2.3 billion years.

Deimos's age is estimated at approximately 2.26 billion years.

Phobos will collide with Mars in about 10 million years.

Abstract

Phobos, a moon of Mars, is below the Clarke synchronous orbit and due to tidal interaction is losing altitude. With this altitude loss it is doomed to the fate of total destruction by direct collision with Mars. On the other hand Deimos, the second moon of Mars is in extra-synchronous orbit and almost stay put in the present orbit. The reported altitude loss of Phobos is two meter per century by wikipedia and sixty ft per century according to ozgate url . The reported time in which the destruction will take place is fiftyMy and fortyMy respectively. The authors had proposed a planetary-satellite dynamics based on detailed study of Earth-Moon. Based on this planetary satellite dynamics, two meter/century approach velocity leads to the age of Phobos to be twenty three Gyrs which is physically untenable since our Solar System age is four and a half Gyrs. Hence the present altitude loss is assumed to be twenty meter per century. This leads to the age of Phobos to be two decimal three Gyrs and age of Deimos to be two decimal two six Gyrs which is an acceptable result and from this analysis it is predicted that the travel time from the present orbital radius of nine thousand three hundred and eighty km to the Martian surface at three thousand, three hundred and ninety seven km is ten decimal and four Myrs. Hence doomsday of Phobos is at ten decimal and fourMyrs from now. Mars Express studies have confirmed that Phobos is indeed trapped in a death spiral.