How Does Mars Compare To Earth In Size

Introduction

Mars is no identify for the faint-hearted. It's dry, rocky, and bitter cold. The 4th planet from the Sun, Mars is i of Globe's 2 closest planetary neighbors (Venus is the other). Mars is 1 of the easiest planets to spot in the dark sky – it looks like a bright cherry point of lite.

Despite existence inhospitable to humans, robotic explorers – similar NASA'due south new Perseverance rover – are serving equally pathfinders to eventually get humans to the surface of the Reddish Planet.

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Namesake

Mars was named past the ancient Romans for their god of war because its reddish color was reminiscent of blood. Other civilizations also named the planet for this aspect – for instance, the Egyptians called it "Her Desher," meaning "the ruby-red one." Even today, information technology is frequently chosen the "Red Planet" considering iron minerals in the Martian clay oxidize, or rust, causing the surface to wait red.

Potential for Life

Scientists don't expect to find living things currently thriving on Mars. Instead, they're looking for signs of life that existed long ago, when Mars was warmer and covered with water.

Size and Altitude

Size and Distance

With a radius of 2,106 miles (3,390 kilometers), Mars is about one-half the size of Earth. If Earth were the size of a nickel, Mars would be nearly equally big as a raspberry.

From an average distance of 142 million miles (228 meg kilometers), Mars is i.5 astronomical units away from the Lord's day. One astronomical unit of measurement (abbreviated as AU), is the altitude from the Sun to Earth. From this altitude, it takes sunlight 13 minutes to travel from the Sun to Mars.

Orbit and Rotation

Equally Mars orbits the Sunday, information technology completes 1 rotation every 24.6 hours, which is very similar to one day on Earth (23.9 hours). Martian days are chosen sols – short for "day." A yr on Mars lasts 669.6 sols, which is the same as 687 Earth days.

Mars' axis of rotation is tilted 25 degrees with respect to the aeroplane of its orbit around the Dominicus. This is some other similarity with Earth, which has an axial tilt of 23.4 degrees. Like Earth, Mars has singled-out seasons, but they last longer than seasons here on World since Mars takes longer to orbit the Lord's day (because it's farther away). And while here on World the seasons are evenly spread over the year, lasting 3 months (or one quarter of a year), on Mars the seasons vary in length considering of Mars' elliptical, egg-shaped orbit around the Sun.

Jump in the northern hemisphere (autumn in the southern) is the longest season at 194 sols. Autumn in the northern hemisphere (spring in the southern) is the shortest at 142 days. Northern winter/southern summer is 154 sols, and northern summer/southern winter is 178 sols.

A 3D model of Mars, a terrestrial planet. Credit: NASA Visualization Technology Applications and Development (VTAD) › Download Options

Moons

Mars has two small moons, Phobos and Deimos, that may be captured asteroids. They're spud-shaped because they accept besides footling mass for gravity to make them spherical.

Close up on potato-shaped Phobos — Mars' largest moon Phobos every bit seen by Mars Reconnaissance Orbiter in 2008. Credit: NASA/JPL-Caltech/University of Arizona | › Full paradigm and caption

The moons become their names from the horses that pulled the chariot of the Greek god of war, Ares.

Phobos, the innermost and larger moon, is heavily cratered, with deep grooves on its surface. It is slowly moving towards Mars and will crash into the planet or break apart in about 50 million years.

Deimos is about half equally big as Phobos and orbits two and a half times farther away from Mars. Oddly-shaped Deimos is covered in loose dirt that often fills the craters on its surface, making it appear smoother than pockmarked Phobos.

Get farther. Explore the Moons of Mars ›

Rings

Mars has no rings. However, in 50 million years when Phobos crashes into Mars or breaks apart, information technology could create a dusty ring around the Red Planet.

Formation

Germination

When the solar organization settled into its electric current layout about 4.v billion years ago, Mars formed when gravity pulled swirling gas and dust in to become the quaternary planet from the Dominicus. Mars is about half the size of Earth, and like its young man terrestrial planets, it has a central core, a rocky drape, and a solid chaff.

Structure

Mars has a dense core at its centre between 930 and 1,300 miles (i,500 to two,100 kilometers) in radius. It's made of iron, nickel, and sulfur. Surrounding the cadre is a rocky mantle between 770 and 1,170 miles (1,240 to one,880 kilometers) thick, and to a higher place that, a crust made of iron, magnesium, aluminum, calcium, and potassium. This chaff is betwixt 6 and 30 miles (10 to 50 kilometers) deep.

Surface

The Red Planet is actually many colors. At the surface, we see colors such as brown, gilded, and tan. The reason Mars looks reddish is due to oxidization – or rusting – of atomic number 26 in the rocks, regolith (Martian "soil"), and dust of Mars. This dust gets kicked up into the temper and from a distance makes the planet appear mostly red.

Interestingly, while Mars is near half the bore of World, its surface has nearly the same area equally Earth's dry land. Its volcanoes, impact craters, crustal movement, and atmospheric conditions such as grit storms have altered the landscape of Mars over many years, creating some of the solar system's most interesting topographical features.

A big coulee arrangement chosen Valles Marineris is long enough to stretch from California to New York – more than 3,000 miles (4,800 kilometers). This Martian canyon is 200 miles (320 kilometers) at its widest and four.3 miles (7 kilometers) at its deepest. That'south nearly x times the size of Earth'due south Grand Canyon.

Composite image of Mars showing massive canyon stretching across most of its surface. Overlay of United States borders on a composite image of Mars's Valles Marineris. The canyon is longer than the U.S. is wide.

A Thousand Calibration

This infographic uses composite orbiter images and an outline of the United states to evidence the scale of the Valles Marineris. Credit: NASA/Scott Hulme | › Full image and caption

Mars is home to the largest volcano in the solar system, Olympus Mons. It's three times taller than Earth's Mt. Everest with a base the size of the state of New Mexico.

Mars appears to take had a watery by, with ancient river valley networks, deltas, and lakebeds, likewise every bit rocks and minerals on the surface that could merely take formed in liquid water. Some features suggest that Mars experienced huge floods well-nigh 3.v billion years ago.

There is water on Mars today, but the Martian atmosphere is too thin for liquid water to be for long on the surface. Today, water on Mars is institute in the course of water-ice just under the surface in the polar regions every bit well every bit in briny (salty) water, which seasonally flows downwardly some hillsides and crater walls.

Atmosphere

Temper

Mars has a thin atmosphere made up mostly of carbon dioxide, nitrogen, and argon gases. To our eyes, the heaven would exist hazy and red because of suspended dust instead of the familiar blue tint we see on World. Mars' sparse temper doesn't offering much protection from impacts past such objects as meteorites, asteroids, and comets.

The temperature on Mars tin can be as high as seventy degrees Fahrenheit (20 degrees Celsius) or as low as most -225 degrees Fahrenheit (-153 degrees Celsius). And because the atmosphere is so thin, estrus from the Sunday easily escapes this planet. If you were to stand on the surface of Mars on the equator at noon, it would feel like spring at your feet (75 degrees Fahrenheit or 24 degrees Celsius) and wintertime at your head (32 degrees Fahrenheit or 0 degrees Celsius).

Occasionally, winds on Mars are potent enough to create dust storms that encompass much of the planet. Afterwards such storms, it can be months before all of the dust settles.

Magnetosphere

Mars has no global magnetic field today, but areas of the Martian crust in the southern hemisphere are highly magnetized, indicating traces of a magnetic field from four billion years ago.