8 Facts About Mars That Will Surprise You

Most of us are familiar with popular facts about Mars, such as it being the fourth planet closest to the Sun, the smallest planet in our Solar System after Mercury, the origin of its name (named after the Roman God of War), etc. However, there are plenty of facts about the red planet that we are not that acquainted with. Let’s take a look at eight unusual facts about Mars that will surprise you.

Largest Impact Crater (3,300 km)


Mars contains the largest impact crater/basin in the Solar System measuring over 3,300 km. Named Utopia Planitia, the impact basin stretches across nearly half of the panet’s diameter. It has a hard surface crust which was formed by mineral solutions moving upwards through the soil and evaporating on its surface. It is believed that a Pluto-sized body struck the surface of Mars some 4 billion years ago creating the impact basin and causing the dichotomy in the Martian hemisphere.

Highest Mountain/Volcano in The Solar System


Mars is home to our solar system’s largest shield volcano mountain. Named Olympus Mons, the volcano is located on the western hemisphere and is the youngest of Mars’ large volcanoes. Olympus Mons has a distinct asymmetrical shape and a gently sloping profile of only 5º.

Huge Ocean


NASA has found data pointing to the fact that an ancient, massive ocean once covered nearly half of the red planet’s northern hemisphere. In some places, the ocean was a mile deep and held over 20 million cubic kilometers of water...more than that contained in the Arctic Ocean. After its formation (around 4.5 billion years ago), Mars was a warm planet containing long-standing lakes, winding river deltas, and numerous streams; however, the atmosphere thinned over time, leading to evaporation. A reduction in the planet’s atmospheric pressure also precipitated this evaporation. During this period, Mars lost most of its insulation and with it, the ability to keep its water liquid. This caused the ocean to recede and eventually freeze.

Unusual Moons


The red planet has two relatively small moons called Deimos and Phobos. They are locked tidally and are only visible on one side of Mars. Their movements/orbit over the planet are also different from that of Earth’s moon. Deimos is just on the outside of the planet’s synchronous orbit and as such, rises in the east, though it does so very slowly. It takes about 2.7 days to set in the west (despite its thirty-hour orbit) since its speed is a bit slower than that of Mars’ rotation. Phobos, on the other hand, rises in the west and sets in the west, then rises again after eleven hours.

The Red Planet?


Mars is often called the red planet because of how it looks when viewed from the Earth. This “redness” is due to the presence of a rust atmospheric layer on the planet; however, a closer look will show that its surface is actually multi-hued, with colors such as green, tan, brown, gold, and others present. These colors on Mars’ terrain are present as a result of minerals like phosphorus, chlorine, and sulfur.

Blue Sunsets


The fine dust permeating the atmosphere on Mars allows blue light to pass through more efficiently than other longer wavelengths present in UV light. This means that when sunlight shines through the atmosphere on Mars, blue light is more pronounced near the direction of the sun. This effect becomes more obvious at sunset than at other times since the light from the sun takes longer to travel through the planet’s atmosphere than when it is on the horizon.

Gravity on Mars Causes Loss of Bone Density


Although many people know that gravity on the planet Mars is a third of Earth’s, it is not widely known that whenever individuals visit the red planet, their muscles slowly begin to deteriorate. When gravity is reduced or stops working on the body, the bones loses minerals, resulting in a 1% drop in density every month. On Earth, the rate of bone density loss in the elderly varies from 1 – 1.5% yearly. After spending time on Mars and returning to Earth, it may not be possible to correct the bone loss by rehabilitation, placing you at greater risk of developing osteoporosis-related fractures later in life. While on Mars, astronauts who don’t eat properly or exercise regularly will experience cardiovascular deconditioning, and lose muscle strength and endurance since it takes only a small amount of effort to float through space.

More In-depth Information


Currently on a 7-month interplanetary journey to Mars, the Mars InSight lander (an acronym for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) was designed by NASA to probe deep in search of more facts about the planet. Although this isn’t the first probe to be sent to Mars, it is the first that will dig very deeply for scientific answers. Unlike other landers which roamed around the planet, the InSight lander will be stationary to enable it carefully measure the properties of the Martian interior such as temperature, size and shape of the planet’score, and seismic activity.