Uploaded November 2020 | Updated September 2026, 2 hours ago
The next two terrestrial planets in the solar system after Mercury and Venus are our home planet Earth and Mars. In this video, we will be going over some basic features of these two worlds.
Earth, our home, is the third planet from the Sun and is the only known planet to support life. 70% of Earth’s rocky surface is covered by Earth’s global ocean with a depth of about 4 km (or 2.5 miles). It is the fifth-largest planet in the solar system with a thin layer of atmosphere consisting mainly of nitrogen and oxygen. It also contains trace amounts of other gases such as carbon dioxide, helium, and hydrogen, as well as water vapor. The presence and distribution of water vapor in the atmosphere is responsible for much of Earth’s weather. The atmosphere also affects Earth’s long-term climate and short-term local weather and shields us from much of the harmful radiation coming from the Sun. It also protects us from meteors since most of them burn up before they can strike the surface as meteorites. The Earth is approximately 150 million km from the Sun with a mass of about 5.9x10^24 kg and surface gravity of about 9.8m/s^2. The orbital period of Earth is about 365 days with its rotation period almost equal to its successive sunrises both being roughly 24 hours. The axis of rotation of Earth is tilted at 23.45 degrees with respect to Earth’s orbit around the Sun which causes the 4 seasons to occur here on Earth. Our planet’s rapid rotation and molten nickel-iron core give rise to a magnetic field that protects us from charged particles fired from the Sun known as “solar wind” by trapping them in the magnetic field. Furthermore, Earth’s lithosphere, which includes the crust (both continental and oceanic) and the upper mantle, is divided into huge plates that are constantly moving. Earthquake results when these plates grind past one another, ride up over one another, collide to make mountains, or split and separate. Earth is also known to have only one natural satellite called the moon which has no atmosphere and is covered by craters made by asteroids, comets, and meteoroids. Earth’s moon plays a vital role in Earth’s stable climate and the maintenance of tides. The Earth is made up of complex, interactive systems that create a constantly changing world that we are still striving to understand.
Mars is the fourth planet from the Sun with a rocky body about half the size of Earth. It is often referred to as the “Red Planet” due to the effects of iron oxide found on its surface giving it a distinct reddish appearance. At an average distance of 228 million km from the Sun, Mars is about 6.4x10^23 kg with a surface gravity of 3.7m/s^2 or about 38% of Earth’s. Similar to Earth, Mars has an orbital period of approximately 1.8 Earth years with its rotation period and successive sunrises being just a little over 24 hours. Moreover, just like Earth, Mars experiences seasons because of the tilt of its rotational axis, however, they last longer than the seasons of Earth. It has a thin atmosphere composed of mainly carbon dioxide, nitrogen, and argon with cold temperatures ranging from –87 to –5 deg C (–125 to 23 deg F). Due to this, liquid water cannot exist at the surface of Mars for long, but NASA’s Mars Odyssey orbiter has detected hydrogen-rich polar deposits, indicating large quantities of water ice close to the surface. In 2004, the Mars Exploration Rover named Opportunity found structures and minerals indicating that liquid water was once present at its landing site. The polar ice caps on Mars grow and recede with the seasons; layered areas near the poles suggest that the planet’s climate has changed more than once. Mars is believed to have been very active with volcanic activity some 3.5 billion years ago altering its surface. Olympus Mons is the largest volcanic mountain in the solar system found on Mars along with Valles Marineris, a vast canyon system that makes the Grand Canyon look like a small crack in the ground. Furthermore, scientists also believe that Mars experienced huge floods about 3.5 billion years ago carving Mars’ great channels and flood plains. Mars has two small moons, Phobos and Deimos, that might be captured asteroids. Because of their little mass, they are shaped more like a Potato rather than a sphere like the Earth’s moon. Phobos, the innermost moon, is heavily cratered, with deep grooves on its surface. With some of its similar conditions to Earth, Mars might even be the next home for humanity.
The next two terrestrial planets in the solar system after Mercury and Venus are our home planet Earth and Mars. In this video, we will be going over some basic features of these two worlds.
Earth, our home, is the third planet from the Sun and is the only known planet to support life. 70% of Earth’s rocky surface is covered by Earth’s global ocean with a depth of about 4 km (or 2.5 miles). It is the fifth-largest planet in the solar system with a thin layer of atmosphere consisting mainly of nitrogen and oxygen. It also contains trace amounts of other gases such as carbon dioxide, helium, and hydrogen, as well as water vapor. The presence and distribution of water vapor in the atmosphere is responsible for much of Earth’s weather. The atmosphere also affects Earth’s long-term climate and short-term local weather and shields us from much of the harmful radiation coming from the Sun. It also protects us from meteors since most of them burn up before they can strike the surface as meteorites. The Earth is approximately 150 million km from the Sun with a mass of about 5.9x10^24 kg and surface gravity of about 9.8m/s^2. The orbital period of Earth is about 365 days with its rotation period almost equal to its successive sunrises both being roughly 24 hours. The axis of rotation of Earth is tilted at 23.45 degrees with respect to Earth’s orbit around the Sun which causes the 4 seasons to occur here on Earth. Our planet’s rapid rotation and molten nickel-iron core give rise to a magnetic field that protects us from charged particles fired from the Sun known as “solar wind” by trapping them in the magnetic field. Furthermore, Earth’s lithosphere, which includes the crust (both continental and oceanic) and the upper mantle, is divided into huge plates that are constantly moving. Earthquake results when these plates grind past one another, ride up over one another, collide to make mountains, or split and separate. Earth is also known to have only one natural satellite called the moon which has no atmosphere and is covered by craters made by asteroids, comets, and meteoroids. Earth’s moon plays a vital role in Earth’s stable climate and the maintenance of tides. The Earth is made up of complex, interactive systems that create a constantly changing world that we are still striving to understand.
Mars is the fourth planet from the Sun with a rocky body about half the size of Earth. It is often referred to as the “Red Planet” due to the effects of iron oxide found on its surface giving it a distinct reddish appearance. At an average distance of 228 million km from the Sun, Mars is about 6.4x10^23 kg with a surface gravity of 3.7m/s^2 or about 38% of Earth’s. Similar to Earth, Mars has an orbital period of approximately 1.8 Earth years with its rotation period and successive sunrises being just a little over 24 hours. Moreover, just like Earth, Mars experiences seasons because of the tilt of its rotational axis, however, they last longer than the seasons of Earth. It has a thin atmosphere composed of mainly carbon dioxide, nitrogen, and argon with cold temperatures ranging from –87 to –5 deg C (–125 to 23 deg F). Due to this, liquid water cannot exist at the surface of Mars for long, but NASA’s Mars Odyssey orbiter has detected hydrogen-rich polar deposits, indicating large quantities of water ice close to the surface. In 2004, the Mars Exploration Rover named Opportunity found structures and minerals indicating that liquid water was once present at its landing site. The polar ice caps on Mars grow and recede with the seasons; layered areas near the poles suggest that the planet’s climate has changed more than once. Mars is believed to have been very active with volcanic activity some 3.5 billion years ago altering its surface. Olympus Mons is the largest volcanic mountain in the solar system found on Mars along with Valles Marineris, a vast canyon system that makes the Grand Canyon look like a small crack in the ground. Furthermore, scientists also believe that Mars experienced huge floods about 3.5 billion years ago carving Mars’ great channels and flood plains. Mars has two small moons, Phobos and Deimos, that might be captured asteroids. Because of their little mass, they are shaped more like a Potato rather than a sphere like the Earth’s moon. Phobos, the innermost moon, is heavily cratered, with deep grooves on its surface. With some of its similar conditions to Earth, Mars might even be the next home for humanity.
