The height of Mount Everest

As the highest mountain on Earth, the great name of Mount Everest can be said to be known to all people on Earth, but in the solar system, the Earth is not the only planet with mountains, so other planets in the solar system, is there a higher mountain than Mount Everest?

The answer is yes, for example, Mount Maxwell on Venus. Mount Maxwell is located in the northern hemisphere of Venus (closer to the north pole of Venus), and the detection data show that the highest peak of this mountain is 10,943 meters above Venus' datum, which is higher than Mount Everest, yet Mount Maxwell is not considered the highest in the solar system.

(↑Maxwell Mountain)

Where is the tallest mountain in the solar system?

From the known exploration data, the highest mountain in the solar system is located on Mars, and it is named Mount Olympus, which is located in the northern hemisphere of Mars (the specific location is 18.65°, 226.2°E). The exploration data shows that the highest peak of Mount Olympus is 21,171 meters above the Martian datum, which is far higher than Mount Everest on Earth.

We know that the Himalayas, to which Mount Everest belongs, were formed by the collision of plates, while the formation mechanism of Mount Olympus is not the same, in simple terms, it is formed by the gradual accumulation of underground magma after cooling, because the shape of this mountain is very similar to a shield, so it is called "shield volcano".

There are also "shield volcanoes" on Earth, the highest of which is located in the middle of the Hawaiian Islands Bold Naroya volcano, but the altitude of this mountain is only 4,170 meters, even from the foot of its location below sea level to calculate the height of its foot to the summit is only 10,203 meters, simply can not be compared with Olympus.

It is also a "shield volcano", but why are the mountains on Mars so much higher? The main reason is that the mass of Mars is much smaller than that of the Earth, the same mass of objects on Mars by the gravity will of course be much lower than on Earth, and the low gravity environment allows the mountains on Mars to "grow" higher, not to be easily "crushed" by gravity ".

What is the height of Mount Everest in the solar system?

If we limit the range to the big planets in the solar system, Everest's height can be ranked 7th, in order from lowest to highest, preceded by Maxwell (as we have already mentioned), Elysium (on Mars, 14,127 meters), Parmonis (on Mars, about 15,000 meters), Althea (on Mars, 17,781 meters), and Aeschylus (on Mars, 17,781 meters). 17,781 m), Mount Eskrells (18,225 m on Mars), and Mount Olympus.

(↑ Equatorial ridge on Titan VIII)

If we extend the range to smaller planets in the solar system, the ranking of Mount Everest will move back a bit, for example, the equatorial ridge on Titan VIII reaches a maximum of about 20,000 meters, while Mount Boazoli on Io has a height of at least 16,000 meters.

In particular, the "peak" in the central region of the Rhea Silveria basin on Vesta can reach heights of 20 to 25 km (there is not enough data to give a range), so it is thought that this "peak" is the tallest in the solar system, but since The height of this "peak" is actually calculated from its base to its summit, so it is still commonly believed that Olympus is the tallest mountain in the solar system, because the Rhea Silvia basin is a meteorite impact crater.

(↑Vesta)

Some people may say here that the height of Mount Everest refers to its height above the sea level of the Earth, while there is no ocean on other planets, so of course, there is no sea level, so this ranking is unfair to Mount Everest.

Well, to be fair, let's see again how high Mount Everest would be if all the oceans on the Earth were removed.

When we describe the height of an object, we need to use a datum to define the "height to zero", on Earth, the mean sea level is a natural datum, while for planets without liquid oceans, we need to use other methods to define a datum.

How to define it? A common method is to use a gravity field model of the planet to calculate gravity equipartition that is closest to the average height of the planet's surface and use it as a datum to describe the height of objects on the planet's surface.

On Earth, we call the gravitational equilibrium plane that coincides with the surface of the stationary ocean the "geoid", which is equivalent to what we often call sea level.

It is known that the volume of the earth's oceans is about 1.37 billion cubic kilometers, and the earth's surface area is about 510 million square kilometers, a simple calculation shows that if the earth's oceans are evenly spread on the earth's surface, then its depth is about 2686 meters, that is if all the earth's oceans are removed, then the height of Mount Everest will be increased by 2686 meters based on the existing, that is, about 11534 meters.

As you can see, even if all the oceans on Earth were removed, Everest would only rank higher than Mount Maxwell on Venus in the solar system, and its height would still be far lower than the tallest mountain in the solar system.