NASA’s Perseverance Rover recently provided a stunning glimpse of Phobos eclipsing the Sun from Mars’ surface, giving scientists and space enthusiasts an awe-inspiring view of the phenomenon. This occurrence, while captivating for humans, may have appeared ominous to any potential Martian microbes if they exist, as the Moon is predicted to collide with the red planet in the distant future.
Phobos, the closest of Mars’ two moons, is steadily approaching the planet and will eventually either crash into it in approximately 50 million years or disintegrate into a ring, according to NASA. The recent eclipse observed by the Perseverance Rover allowed scientists to deepen their understanding of Phobos’ gradual descent towards Mars.
Meanwhile, Mars’ other moon, Deimos, is moving further away from the planet and will eventually depart from its orbit altogether. This juxtaposition of the two moons’ trajectories presents an intriguing contrast in their ultimate destinies.
While the future collision between Phobos and Mars is inevitable, Earth is also experiencing changes that will ultimately affect celestial events like solar eclipses. Our own Moon is slowly drifting away from Earth at a rate of 3.78 centimeters (1.5 inches) per year. Consequently, in the distant future, total solar eclipses may no longer be visible, as the Moon will appear too small to completely cover the Sun.
Richard Vondrak, a lunar scientist at NASA’s Goddard Space Flight Center, explained in 2017 that the number and frequency of total solar eclipses will decrease over time. He predicted that Earth will witness its final total solar eclipse approximately 600 million years from now.
The Moon’s present ability to perfectly eclipse the Sun is, in fact, a fortunate accident. Due to the Sun’s vast distance from Earth, it appears similar in size to the Moon, as the former is approximately 400 times larger in diameter. However, around four million years ago, when the Moon was positioned differently in its orbit, it would have appeared three times larger in the sky.
In an ironic twist, our planet’s demise will likely precede the separation from the Moon’s gravitational influence. Scientists predict that the Sun will eventually expand into a Red Giant and engulf Earth before such a separation occurs, highlighting the ephemeral nature of our existence.
Although the future holds diminishing opportunities to witness grand astronomical events like total solar eclipses, the recent Perseverance Rover’s capture of Mars’ moon Phobos eclipsing the Sun offers us a glimpse into the captivating mysteries of our cosmic neighborhood.