What mysteries does Titan hide?
Titan is Saturn's most significant natural satellite,
having a diameter of 3,200 miles (5,149.5 km), being even bigger than Mercury.
It is the only satellite with a significant atmosphere and the only object other than
Earth on which clear evidence of stable liquid bodies has been found on the surface.
What other mystery hides this excellent satellite? Could it have conditions to host
extraterrestrial life? let's start!
Titan was discovered on March 25, 1655, by the famous Dutch astronomer Christiaan Huygens and,
from then on, would be cataloged as the largest of Saturn's satellites.
Titan has a diameter 50% larger than the Moon and is 80% more massive; it is bigger
in volume than the planet Mercury, although it only has 40% of the mass of the latter;
this means that despite being more big than Mercury, Titan is lighter, because Mercury has
a giant metallic core, while Titan is composed of lightweight materials such as rocks and ice.
Due to the low density of Titan, its gravitational pull force is only 1.35 m / s2;
this means that an object of 1 kg on Earth would weigh only 140 grams on Titan; thanks to this,
an ordinary human on the surface of Titan could lift weighty objects without almost any effort.
According to the available data on Titan, its atmosphere could be composed mainly of nitrogen,
but up to 6% can be methane and complex hydrocarbon compounds. The climate,
including wind and rain, creates Land-like landforms such as dunes, rivers, lakes, and seas
(of liquid methane and ethane) and is dominated by seasonal weather patterns as on Earth.
With its liquids (both surface and underground) and robust nitrogen atmosphere, Titan's methane
cycle is seen as an analogy to Earth's water cycle, albeit at a much lower temperature.
Water on Titan On June 28, 2012,
NASA's Cassini spacecraft data revealed that Saturn's moon Titan could likely harbor a
layer of liquid water beneath its ice shell. Scientists discovered this by measuring Titan's
tides. Saturn's powerful gravity stretches and warps Titan as the
satellite moves around the gas giant planet. If Titan were composed entirely of hard rocks,
Saturn's gravitational pull would have to cause bulges, or "solid tides," on the moon just 3
feet (1 meter) high. Instead, the data shows that Saturn creates solid tides about 30 feet
(10 meters) high. This suggests that Titan is not composed entirely of rocky solid material.
First, scientists weren't sure Cassini could detect the bulges caused by Saturn's pull on
Titan. However, Cassini succeeded and measured Titan's gravitational field during six close
flybys, which took place from February 27, 2006, to February 18, 2011. These gravity measurements,
made with the help of NASA's Deep Space Network (DSN), revealed the magnitude of Titan's tides.
An ocean layer must not be huge or deep to create the observed tides.
A liquid layer between the deformable outer crust and a solid mantle would
allow Titan to form the bulges and compress as it orbits Saturn.
As Titan's surface is composed mainly of water ice, which abounds on the moons of the outer solar
system, scientists believe that Titan's ocean is likely to be composed mainly of liquid water.
On Earth, tides result from the Moon's and Sun's gravitational pull onto our oceans
at the surface. They can reach 2 feet (60 centimeters) in the open oceans. The Sun's
and Moon's gravitational pull also causes the Earth's crust to form bulges, thus creating
solid tides of about 20 inches (50 centimeters). But let's not get excited; according to experts,
an underground layer of liquid water on Titan is not an indicator of life. Since scientists
believe that life is more likely to arise when liquid water is in contact with rock,
these measurements cannot tell whether the ocean floor is composed of rock or ice.
A satellite with a planet atmosphere Titan is the only known natural satellite
with a dense atmosphere. The first person to suggest that Titan could have an atmosphere
was the Spanish astronomer Josep Comas I. Solà in 1907 because of the darkening effect at the edge.
Gerard P. Kuiper confirmed the presence of a significant atmosphere in 1944 from spectra
taken from telescopes on high-altitude aircraft. The Voyager 1 probe showed in 1981 that Titan's
atmosphere is 1.19 times denser than Earth's. In addition, we must remember that Titan's
gravitational pull force is feeble due to its low mass; this causes its atmosphere
to extend much more than that of the Earth; for comparison, the limit of the Earth's mesosphere
is approximately 120 km high, while the limit of Titan's mesosphere is more than 600 km high.
Its atmosphere is so large that when the Cassini space probe passed almost 1000 km high,
it had to make trajectory corrections due to the resistance and friction with Titan's atmosphere.
Titan's atmosphere is rich in heavy gases, is composed of 94% nitrogen,
and is the only nitrogen-rich atmosphere in the Solar System apart from our planet,
with significant traces of various hydrocarbons that make up the rest, including methane,
ethane or acetylene, just to name a few. These hydrocarbons are thought to form in
Titan's upper atmosphere in reactions that result from methane's reaction to ultraviolet light from
the Sun, producing a thick orange haze, which is why Titan's atmosphere is so thick. It is
not possible to see through it quickly. This is reminiscent of Venus, as Venus'
atmosphere is also weighty and thick, preventing us from seeing through them.
Another resemblance that Titan has with Venus is that both have a rotating atmosphere;
this means that the atmosphere rotates much faster than the planet's rotation. Astronomers
noticed this when they observed its poles, as each pole has a vortex that rotates every 9
hours while the satellite's rotation is 16 days. Because of this, the winds on Titan are powerful,
reaching 1200 km / h; this makes Titan have one of the most violent atmospheres in the solar system;
with such fast wind gusts, it would be difficult to establish a base on its surface.
Titan is a world extraordinarily abundant in organic compounds, primarily methane.
Probably the liquid hydrocarbon content of this moon (in the form of seas and lakes) is hundreds
of times higher than that of all the Earth's oil and natural gas reserves. In addition,
its dunes possibly contain hundreds of times more organic matter than all of Earth's coal reserves.
Oceans, rivers and lakes off land. Methane on Titan fulfills the role
of water on Earth and forms clouds in its atmosphere. When it condenses,
it forms clouds that produce methane rain with particles that fill the Satellite's channels
and rivers with a black material that flows until it reaches the lakes and seas of Methane.
In this sense, Titan is the place in the solar system most similar to Earth since
it is the only place besides our planet where there is a cycle identical to that of water.
Before Cassini's arrival, radar observations from Earth and those from the Hubble Space
Telescope had traversed the opaque haze and shown the heterogeneous nature of Titan's surface. Also,
since the Voyager missions, it was believed that low atmospheric temperatures could turn
Methane into raindrops, but it was unknown if the lakes were part of that irregular orography.
In mid-2005, a dark region of about fifteen thousand square kilometers in the shape of
a foot footprint was detected at Titan's south pole. The smooth regions looked obscured on radar,
so it was believed it could constitute the first lake candidate on Titan.
Later in 2008, the spectroscopic analysis was published that confirmed that it was a liquid
surface composed of ethane and, possibly, methane, nitrogen, and other hydrocarbons, a true milestone
in the history of astronomy since it was the first reservoir of stable liquid outside our planet.
A lake that, as it became known later, shows a highly smooth surface,
with maximum variations in the height of three millimeters, practically like a mirror.
The Cassini probe, using its radar system, captured on July 21, 2006, two "dark spots,"
similar to terrestrial lakes; the "spots" measure 420 kilometers by 150 and 475 by 150 and are at
the north pole of Titan, that is, where the lowest temperatures of the Satellite are.
Titan has an angle of tilt of its axis of 27 degrees, making it have colder
seasons and other warmer areas just like what happens on earth. On July 8, 2009,
the Cassini probe photographed a specular reflection over the Satellite's north pole,
confirming the presence of liquid on the surface. Titan's two largest lakes are
Lake Ligeia Mare and Lake Kraken. Ligeia Mare is located at the north pole and
has an area of 126,000 square kilometers, making it larger than Lake Superior in North America.
The Kraken Lake is the largest; it has a depth of probably more than 300 meters, its maximum length
is 1,170 km, and it covers 500,000 km², giving it an area bigger than that of the Caspian Sea.
These lakes are so large that scientists call them seas rather than lakes.
Life on Titan Titan is unique in our solar system. It is
dotted by lakes and dunes and shrouded in a thick atmosphere of nitrogen and methane; this moon is a
frozen time capsule that houses the conditions that existed on Earth in its early days.
Although the liquid on Titan's surface is methane rather than water, this satellite
is the only body in the solar system, apart from Earth, that has liquid on its surface and,
therefore, conditions to mix the amino acids necessary to create proteins,
therefore, give rise to living beings. However, so far, the evidence is insufficient.
On January 14, 2005, the Huygens probe successfully descended on Titan's surface
in a region known as Adiri, obtaining images during its descent and on the
surface. The panorama during the descent shows gentle hills with drainage channels.
The channels seem to lead to a nearby, wide, flat, and dark region. It seems even to see an area of
coastline and even islands and what appears to be a sea of methane, all in a misty environment.
ESA scientists estimate that the probe could have descended on Titan's dark region, so the
image taken after landing shows a flat surface covered by stones in the form of rounded pebbles;
these could be made mostly of water ice. Do not forget that, on Titan, there is no liquid water
on its surface, although there is frozen water. Despite the probes and the efforts that have been
made to study this satellite, we lack much data that help us reveal the secrets of its atmosphere,
so there is currently a project called DragonFly, which consists of a NASA space
exploration probe that will send a shuttle with a robotic drone to Titan, to study
prebiotic chemistry and planetary habitability, performing flights with vertical takeoffs and
landings in various places of the satellite. Would you like us to make a video explaining
this fascinating mission? Let us know your opinion in the comments.