The largest satellite in the solar system is Ganymede, with a diameter of 5,622 km.
Huygens discovered the Titan moon
In 1655, the young Christiaan Huygens finished building with his hands a telescope 5 cm in diameter and three and a half meters in length, which allowed him to obtain about 50 magnifications.
With this telescope, he had the immense joy of seeing the four satellites of Jupiter discovered by Galileo.
The following year, after tracking it every night for several months, and measuring its period and orbit, he broke the news. On March 25 of that year he also saw a satellite not of Jupiter, but of Saturn. It was the fifth satellite besides the Moon.
The name “Titan” was given to him by John Hershel (son of William Hershel) in 1847, when he suggested the name of the Titans, brothers and sisters of Cronus (the Greek name for the Roman god of time Saturn) to designate the satellites of Saturn that at that time were known by the numerals from 1 to 7.
Huygens could never even imagine that 350 years later, man would be able to send an artifact to land on the ground of this moon that he always contemplated as a point of light moving around the great Saturn.
Less could he imagine that this marvel of technology was going to be named after him: Huygens probe.
Titan moon size
Titan is Saturn’s largest moon and the second largest satellite in the entire solar system. The largest satellite in the solar system is Ganymede, with a diameter of 5,622 km.
Titan’s diameter is 5,150 km
The diameter of the Earth is 12,742 km
The diameter of the Moon is 3,476 km
Titan’s physical characteristics
Titan is one moon that arouses the greatest interest due to its physical characteristics, very similar to those of our Earth.
More details have been observed during the Cassini probe’s approach to Titan, thanks mainly to the use of the spacecraft’s radar.
Through the use of specialized instruments, mountains that are 150 kilometers long, 30 kilometers wide, and 1.5 kilometers high have been seen.
Titan’s surface was virtually unknown before the arrival of the Cassini–Huygens probe.
The Huygens probe descended on Titan on January 14, 2005, and the information it has sent has substantially increased our knowledge of the satellite.
Note that some features with a physical size given by “diameter” may not be circular and actually refers to its length.
These mountains appear to be made of ice covered by a kind of “snow” of organic material.
Titan also appears to have terrains similar to certain terrestrial terrains, albeit with liquid hydrocarbons instead of water and ice.
Rains, rivers and lakes are nothing but methane and ethane.
Some organic materials similar to limestone suggest that there may be underground caverns.
In the winding-down period of its more than 12-year mission exploring the Saturn system, NASA’s Cassini spacecraft has spotted the tallest mountain of Saturn’s largest moon, Titan, a peak in the Mithrim Montes range near the equator that rises over two miles above the moon’s surface.
The Cassini spacecraft measured the peaks of Mithrim Montes using its radar instrument to penetrate the layers of thick, smoggy haze in Titan’s atmosphere.
The highest of the peaks is 10,948 feet high, and most of Titan’s highest peaks, which are found near the equator, are close to 10,000 feet tall.
Comparably high mountains on Earth include Cathedral Peak in Yosemite, Mount Lassen, and Telescope Peak in Death Valley National Park.
Observations made by the Cassini probe show that a region of Saturn’s moon Titan is very similar to the Etosha Salt Flat in Namibia.
Both are lakes are large shallow depressions that are not always filled.
Lake Ontario is the largest lake in Titan’s southern hemisphere. It is slightly smaller than its namesake, North America’s Lake Ontario, but completely different in many other ways. Click here to see all the news.
Methane Rain Possible on Titan
This artistic image of Titan was published in “Astronomy picture of the day 2006 August 2” website https://apod.nasa.gov/apod/ap060802.html.
Recent analyses of measurements taken by the Huygen’s probe that landed on Titan in 2005 January indicate that the atmosphere is actually saturated with methane at a height of about 8 kilometers.
Combined with observations of a damp surface and lakes near the poles, some astrobiologists conclude that at least a methane drizzle is common on parts of Titan.
The findings increase speculation that a wet Titanian surface might be hospitable to unusual forms of life.
Based on data from the Huygens probe, scientist Tetsuya Tokano from the University of Cologne has studied the methane shower that falls as dew on the surface of Titan in the region of descent of the Huygens probe.
These data indicate the presence of a methane-nitrogen cloud that releases raindrops that continually fall on the surface of Titan. Within the solar system, rains only exist on Earth and on Titan.
A comparison of images taken in 2004 and 2005 shows changes in lakes located at the south pole of the moon, which could be attributed to a methane storm that has filled those lakes.
There is a region called Xanadu, which has geological characteristics similar to Earth, with hills, valleys and dunes of dark sand, cut by channels similar to rivers on Earth.
The study of radar observations from the Cassini spacecraft has discovered that Titan has dark brown dunes that rise about 150 meters above the surface and run parallel, side by side, in the ecuator.
According to measurements, Titan’s dunes are probably composed of a central core of water ice surrounded by organic matter, and the “sand” formed by these grains is estimated to be a bit more grainy, but less dense than Earth’s or Earth’s. marciana and that the beans are the size of coffee beans.
The Cassini probe captured two “dark spots” on July 21, 2006, similar to Earth’s lakes, which constitute “powerful evidence” that there are hydrocarbon deposits on the satellite.
The “spots” measure 420 kilometers by 150, and 475 by 150 and are on Titan’s north pole, that is, where temperatures are even lower.
The low temperatures explain that life has not evolved on Titan, despite having the necessary ingredients.
The cold has kept this world as Earth probably was 4 billion years ago. The satellite will continue like this, frozen, unless a meteorite falls on it to activate it.
Titan is the only moon in the Solar System with a dense atmosphere.
The Spanish astronomer Comas y Solà had anticipated it in 1908, based on an obscuration that he detected towards the edge of the satellite.
Titan’s atmosphere is thick and hazy, and mostly nitrogen, like Earth’s.
The images transmitted by the Voyager 1 and Cassini probes show a dense and orange atmosphere, 10 times greater than the Earth’s, composed mainly of nitrogen (94%) and rich in methane, ethane and hydrocarbons.
Its low temperatures should have preserved this composition for 4,000 million years, which is very similar to what the primitive atmosphere of the Earth must have had.
Will it be possible to travel to Titan?
Traveling to Titan and gazing at a moon that is probably what the Earth was like today 4,000 million years ago is an irresistible desire for human beings.
But the ride would be 7 years.
Once the transport problems have been solved, it would be necessary to think about protecting oneself during that time from cosmic radiation and providing sufficient oxygen.
Once on the ground of Titan, to enjoy the passages, the storms, the rain, the rivers and lakes. But, forbidden to drink from them, because they do not contain water, but methane.
You will have to take good binoculars to see in the distance a tiny point of light: the Earth.
Returning to her (to “my house”) is another problem to which, for now, not only has no solution been found, but has not even been sought.
An instructive science fiction novel
To those who are interested in science fiction, I recommend reading the magnificent book “TITAN” published by Ben Bova, a writer with a good pen and remarkable scientific knowledge.
The first edition is from 2006. The story deals with the explorations and adventures of some 10,000 scientists who, in the year 2095, inhabit a space module 20 km long and 4 km in diameter and orbiting Saturn.
The book is read with relish and you learn a lot about what we know about this mysterious moon of Saturn, so similar to our Earth, and about the difficulties involved in exploring it by human beings. There is intrigue, science and suspense.