Solar System Exploration: Solar System 101: Homework Helper

HOMEWORK HELPER

The Hottest Planet
Venus is a dim world of intense heat and volcanic activity. Similar in structure and size to Earth, Venus' thick, toxic atmosphere traps heat in a runaway 'greenhouse effect.' The scorched world has temperatures hot enough to melt lead. Glimpses below the clouds reveal volcanoes and deformed mountains. Venus spins slowly in the opposite direction of most planets.

Extreme Facts

The Longest Day A day on Venus is longer than its year. The planet makes a complete trip around our sun -- a year -- in 225 Earth days. But its sluggish rotation (once every 243 days as measured with respect to the stars) leads to a day/night cycle much different from Earth's. On Venus, a day/night cycle -- 24 hours here on our planet -- lasts 117 Earth days as measured from noon to noon at a location. The combination of Venus' orbital motion and its slow, "backward" rotation makes things very different there.

Too Hot to Handle Venus -- not Mercury -- is the hottest planet in our solar system. Even though Mercury is closer to the sun, Venus' toxic clouds trap the sun's heat. That runaway "greenhouse effect" makes Venus' surface sizzle at about 854 degrees Fahrenheit (457 degrees Celsius). That's hot enough to melt lead.

Backspin If an action hero wanted to ride off into the sunset on Venus, they'd have to head east instead of west. Venus rotates in the opposite direction of the other planets -- a retrograde rotation -- so the sun rises in the west and sets in the east.

Night Light Venus is the brightest planet in Earth's darkening skies. Only the moon -- which is not a planet -- is brighter. Venus outshines the other planets because it is closer and its thick clouds are excellent for reflecting the sun's light.

Girl Power Venus's beauty in the night sky inspired ancient astronomers to name it for the goddess of love and beauty. Almost all the surface features of Venus are named for amazing Earth women. Only one spot -- Maxwell Montes -- is named for the man whose work in physics made surface observations of Venus possible.

Secret Surface Scientists weren't about to let dense clouds, extreme heat and intense pressure stop them from studying the surface of Venus. In 1990, they used the Magellan spacecraft's powerful radar to peer through the clouds and map most of the surface of the planet.

Going Through a Phase Like the Moon, Venus has a full range of phases. It can be "Full" when Venus is on the far side of the sun, "New" when Venus is between the sun and Earth, and a crescent at other points in between.

You Take the High Road and I'll Take the Low Scotland isn't the only place with highlands. A highland is a mountainous region, and the planet Venus has two such regions on its surface: Istar Terra in the upper northern/polar area of Venus and Aphrodite Terra at the equator. However, these two highland areas are gigantic: Ishtar Terra is about the size of Australia and Aphrodite Terra is about the size of South America.

Hot Mountain The highest mountain on Venus is called Maxwell Montes and is comparable to the highest mountain on Earth: Mount Everest. However, a difference between these two giant mountains is that Mount Everest is perpetually covered in snow and Maxwell Montes is never covered in snow: it is too hot on Venus. Surface temperatures on Venus can be over 880 degrees Fahrenheit (471 degrees Celsius).

Dark Shadow Venus is one of the brightest lights in the night -- and morning -- sky; that is why Venus is often referred to as the "morning star." Venus is not a star, but a very bright planet. Venus is so bright that it can cast shadows. Next time you are out on a moonless night, see if you can see your shadow by the light of Venus.

The Longest Day A day on Venus is longer than its year. The planet makes a complete trip around our sun -- a year -- in 225 Earth days. But its sluggish rotation (once every 243 days as measured with respect to the stars) leads to a day/night cycle much different from Earth's. On Venus, a day/night cycle -- 24 hours here on our planet -- lasts 117 Earth days as measured from noon to noon at a location. The combination of Venus' orbital motion and its slow, "backward" rotation makes things very different there.

Too Hot to Handle Venus -- not Mercury -- is the hottest planet in our solar system. Even though Mercury is closer to the sun, Venus' toxic clouds trap the sun's heat. That runaway "greenhouse effect" makes Venus' surface sizzle at about 854 degrees Fahrenheit (457 degrees Celsius). That's hot enough to melt lead.

Backspin If an action hero wanted to ride off into the sunset on Venus, they'd have to head east instead of west. Venus rotates in the opposite direction of the other planets -- a retrograde rotation -- so the sun rises in the west and sets in the east.

Night Light Venus is the brightest planet in Earth's darkening skies. Only the moon -- which is not a planet -- is brighter. Venus outshines the other planets because it is closer and its thick clouds are excellent for reflecting the sun's light.

Girl Power Venus's beauty in the night sky inspired ancient astronomers to name it for the goddess of love and beauty. Almost all the surface features of Venus are named for amazing Earth women. Only one spot -- Maxwell Montes -- is named for the man whose work in physics made surface observations of Venus possible.

Secret Surface Scientists weren't about to let dense clouds, extreme heat and intense pressure stop them from studying the surface of Venus. In 1990, they used the Magellan spacecraft's powerful radar to peer through the clouds and map most of the surface of the planet.

Going Through a Phase Like the Moon, Venus has a full range of phases. It can be "Full" when Venus is on the far side of the sun, "New" when Venus is between the sun and Earth, and a crescent at other points in between.

You Take the High Road and I'll Take the Low Scotland isn't the only place with highlands. A highland is a mountainous region, and the planet Venus has two such regions on its surface: Istar Terra in the upper northern/polar area of Venus and Aphrodite Terra at the equator. However, these two highland areas are gigantic: Ishtar Terra is about the size of Australia and Aphrodite Terra is about the size of South America.

Hot Mountain The highest mountain on Venus is called Maxwell Montes and is comparable to the highest mountain on Earth: Mount Everest. However, a difference between these two giant mountains is that Mount Everest is perpetually covered in snow and Maxwell Montes is never covered in snow: it is too hot on Venus. Surface temperatures on Venus can be over 880 degrees Fahrenheit (471 degrees Celsius).

Dark Shadow Venus is one of the brightest lights in the night -- and morning -- sky; that is why Venus is often referred to as the "morning star." Venus is not a star, but a very bright planet. Venus is so bright that it can cast shadows. Next time you are out on a moonless night, see if you can see your shadow by the light of Venus.