Updated on:


Planets are much smaller than stars in the universe. Despite the fact that they have some fascinating and one-of-a-kind characteristics such as texture, atmosphere, elements present, rings, and so on. Every now and then, we are fortunate to discover new phenomena on or about planets. A similar list of ten lesser-known planet facts follows.


1. Scientists believe that there is a ninth planet in our solar system that is 10 times the size of the Earth. The location of the planet has not been confirmed yet but it is sure that it exists because of its gravitational effects on other objects.

Hypothetical Planet 9 

It is also known as “Planet 9” because it has ten times the mass of the Earth and travels in an elongated orbit 400 times the Earth’s distance from the Sun. Planet 9’s orbit is also likely to be 15 to 25 degrees off the main orbital plane of the solar system, where the rest of the planets travel.

The existence of a new planet was first proposed in 2014, and it quickly gained traction among astronomers. The theories are based on object patterns in a ring of debris in the outer belt known as the “Kuiper Belt.”

It was discovered that the objects in this area were clumped together in a way that suggests the presence of gravitational force from a large body. Planet 9’s evidence has only grown stronger since this discovery.

So far, the only known alternative that contradicts this theory is our lack of understanding of the Kuiper Belt. Researchers believe that the clustering we discovered is the result of “self-gravity,” rather than another planet.

2. There is an exoplanet named J1407b that has more than 30 rings, and each of them is tens of millions of kilometers in diameter. The rings are 200 times larger than Saturn’s.


The star or exoplanet is too far away to directly observe its rings, but we can create a detailed model of its ring system.

Researchers speculated that if we could replace Saturn’s rings with those of J1407b, we would be able to see them at night. This is due to the fact that they would be many times larger than our moon. Not only are its rings massive, but the planet itself dwarfs Saturn and even Jupiter. It is roughly equivalent to 10 to 40 Jupiter masses.

In 2012, the young planet with the massive rings was discovered. Recent research has not only explained the formation of rings, but it has also estimated their mass.

The conclusion was that the ring system is 120 million kilometers in diameter and has a mass equal to the Earth in the form of light-obscuring dust particles.

It orbits a Sun-like star, but J1407b’s ring system blocks 95 percent of its light. Astronomers predict that the rings will become thinner over the next million years.

3. An index was developed in 2015 that suggests Earth is not the most habitable planet found yet. There is a rocky exoplanet named Kepler-442b, 1,100 light-years away from us that is roughly the same size as Earth. This planet has a habitable rating of 0.836 whereas Earth has 0.829.

Size comparison Kepler-442b and Earth. Image credits: Ph03nix1986/Wikimedia

The new scale for determining planet habitability is based on previous methods that primarily relied on the “Goldilocks Zone.” It is at the proper distance from its sun for liquid water to exist.

The new index considers the planets’ rockiness as well as their distance from the sun or star. It implies that the more rock-like a planet, the more habitable it is.

Furthermore, the new index takes into account the eccentricity of planets’ orbits as well as their albedo. The more eccentric the orbit, the more heat and light the planet receives from its star, which can be uneven and sometimes extreme. And albedo is the amount of solar energy reflected off the planet’s surface by its atmosphere.

It is expected that a calculator will be developed for use by exoplanetary researchers on the internet. This will allow them to calculate the habitability of any given planet simply by entering some data.

4. The planet Mars has the longest valley known. It is the Valles Marineris which is 4,000 kilometers long. It is 10 times longer than the Grand Canyon or as long as the US. Researchers aren’t sure how this longest valley was formed.

3d rendered illustration of the mars – Valles Marineris

On Mars, Valles Marineris accounts for roughly one-fifth of the planet’s circumference. It can reach a width of 200 kilometers and a depth of 10 kilometers at some points.

When compared to its Earth counterpart, the Grand Canyon is only 446 kilometers long, 30 kilometers wide at its widest point, and 1.6 kilometers deep.

The valley on Mars extends from east to west and is located just below the equator. It begins in the west at Noctis Labyrinthus and ends near the Chryse Planitia basin.

The canyon system’s formation includes a variety of terrain, such as collapsing pits and massive deserts. All along the way, there are cracks in the crust, cliffs, walls, and landslides.

Scientists have proposed a variety of explanations for the formation of Valles Marineris. The volcanoes in the Tharsis region, however, are widely accepted as the most likely cause.

When viewed through a telescope from Earth, the canyon appears to be a dark scarring on Mar’s surface.

5. The most mass that a planet can have is equal to 13 times the mass of Jupiter. After this certain point, the planet’s own gravity will start to cause a nuclear fusion reaction, and the body would be categorized as a “brown dwarf” or “failed star.”

Jupiter, the largest planet in our solar system, is so massive that even if all other planets were combined into a single mass, Jupiter would still be 2.5 times larger. It’s also worth noting that large planets like Jupiter are simply too small to be considered stars.

A star is typically defined as a body large enough to fuse hydrogen into helium in its core. Large planets and stars are primarily composed of these two elements.

Large planets, on the other hand, have no fusion because they are in a state of hydrostatic equilibrium. This phenomenon prevents the planets from fusing.

A planet must be at least 80 times the mass of Jupiter in order to become a star. However, there are objects that fall somewhere between planets and stars, such as “brown dwarfs.”

Brown dwarfs are star-like objects that lack hydrostatic equilibrium. In order to become a planet, its mass must be 13 times that of Jupiter.

6. The Mercury that we know today is thought to be the almost-exposed core of a planet. It was 4.5 times bigger before it had a collision with another proto-planet that blew away most of Mercury’s crust and mantle.


Mercury was involved in a hit-and-run collision with a planet about the size of Earth 4.5 billion years ago. It did indeed strip the planet’s rocky mantle, which explains why the planet is so small in comparison to others and has such a massive iron core.

In 2011, a spacecraft sent to Mercury discovered the presence of rich volatile elements such as potassium, sulfur, sodium, chlorine, and a massive iron core.

The researchers were perplexed and could only find a possible solution in planet collisions. A model of the collision was created using computer simulations, which supports the idea of the presence of volatile material on the planet.

However, the theory holds true only if Mercury is assumed to be the impactor in the collision that struck the proto-planet with 0.85 times the mass of Earth.

It also suggested that Mars might have had a similar hit-and-run history during its formation.

7. According to researchers, it may be possible for planets Neptune and Uranus to have oceans with liquid diamonds. Experiments conducted under high pressure that mimic conditions on these gas-giant planets show that pieces of diamonds can float on a sea of liquid carbon.

Planets Neptune and Uranus

The research that supports the presence of liquid diamonds on the two planets also provides the first detailed measurement of the melting point of diamond, the hardest natural material known.

Current theories on the two planets suggest that they have solid cores surrounded by an icy mantle of water, ammonia, and methane ices.

Scientists first used lasers to blast diamonds under high pressure. They had to subject diamonds to pressures 40 million times higher than those found at sea level on Earth.

They later compared the conditions to those on Neptune and Uranus. This revealed that they were quite hopeful of discovering a liquid carbon core surrounded by floating diamonds or even “diamond-bergs.”

It’s unclear whether we’ll find diamonds, chunks, or bergs. However, if we do find diamonds, they will be the first solids discovered on these planets.

There are two ways to find out if diamonds float in the oceans of Neptune and Uranus. We must either send spacecraft to the planets or induce similar conditions. Both methods are extremely expensive and would take years to implement.

8. Even if the planet Mercury is extremely hot and is closest to the Sun, it has ice on its surface. The ice could be found in permanently shadowed craters that are never exposed to sunlight.

Planets Neptune and Uranus
Water Ice on Mercury. Image credits: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

The discovery of a red-bright material in Mercury’s north polar region sparked initial speculation about the presence of ice on the planet. Later, the planet’s orbiting spacecraft. Messenger confirmed the presence of water ice weighing between 100 billion and one trillion tons at both poles.

The water ice passed three difficult tests, confirming its presence, according to the spacecraft team. Using hydrogen measurements in radar-bright regions, researchers were able to measure water ice concentrations.

They discovered a hydrogen-rich layer tens of centimeters thick beneath a surficial layer 10 to 12 centimeters thick that is not rich in hydrogen in the polar deposits.

The hydrogen-consistent layer contains nearly pure water ice. Furthermore, the atmospheric conditions on Mercury are such that water cannot exist in a liquid state. The landform may support liquid water in some areas, but the atmosphere quickly converts it to ice or vapors.

9. In cosmical terms, the rings of Saturn are a very brief event. Currently, we have already reached halfway through the 200-million-year lifespan and are very lucky to be able to witness them. However, the planet is losing the rings at the worst-case-scenario rate.

3D Saturn planet and rings close-up.
3D Saturn planet and rings close-up.

The conclusion that the Saturn rings would vanish is based on a phenomenon known as “ring rain.” The process explains how water is drawn from Saturn’s rings and into the planet’s midlatitudes.

The ring rain phenomenon, which is aided by a special type of hydrogen, was successfully explained in 2011. Saturn’s gravity pulls the rings as a dusty rain of ice particles, which is further disrupted by Saturn’s magnetic field.

When the rain was studied, it ate up large chunks of rings weighing between 925 and 6,000 lbs per second. Scientists predicted the life of the rings based on these numbers.

If Saturn’s rings are indeed temporary, then we have surely missed out on seeing the giant rings of other planets such as Jupiter, Neptune, and Uranus. Ringlets can still be seen today, but they are very thin.

10. The farthermost planet from the Sun, Neptune, is warmer than Uranus. This is because it radiates twice as much heat that it receives from the Sun. The extra heat is generated by a phenomenon called “gravitational contraction.”

Planet Neptune
Planet Neptune

We can only measure temperatures in the planet’s outermost layers while researching. So, when we compare the temperatures of Uranus and Neptune in this manner, we find that they are the same.

Scientists argue that this should not be the case because Neptune is farther away from the Sun than Uranus. However, if we consider the temperature of the planets in terms of heat emitted by them rather than heat absorbed by the Sun, Neptune comes out on top.

It is important to note that Uranus, not Neptune, is the oddball here. This is due to Jupiter and Saturn emitting twice as much heat as they absorb from the Sun. Uranus, on the other hand, does not.

Uranus has no internal heat source, whereas Neptune does. And there is no obvious explanation for this. Gravitational contraction occurs when the planets contract gravitationally but slowly, producing extra heat on the other three planets.

Material that falls inward converts its potential energy into thermal energy, which is then released upwards from the planets.

Leave a Comment