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But newer estimates made with help from computer models paint a different portrait. While the same forces would be at work, resurfacing would be piecemeal over an extended time. The average age of surface features could be as young as million years, with some older surfaces mixed in.
Venus is a landscape of valleys and high mountains dotted with thousands of volcanoes. Its surface features — most named for both real and mythical women — include Ishtar Terra, a rocky, highland area around the size of Australia near the north pole, and an even larger, South-America-sized region called Aphrodite Terra that stretches across the equator.
One mountain reaches 36, feet 11 kilometers , higher than Mt. Notably, except for Earth, Venus has by far the fewest impact craters of any rocky planet, revealing a young surface. Or stroll through a deep canyon, Diana, named for the Roman goddess of the hunt.
Tesserae, terrain with intricate patterns of ridges and grooves that suggest the scorching temperatures make rock behave in some ways more like peanut butter beneath a thin and strong chocolate layer on Venus. The Soviet Union landed 10 probes on the surface of Venus, but even among the few that functioned after landing, the successes were short-lived — the longest survivor lasted two hours; the shortest, 23 minutes.
Photos snapped before the landers fried show a barren, dim, and rocky landscape, and a sky that is likely some shade of sulfur yellow. With the hottest surface in the solar system, apart from the Sun itself, Venus is hotter even than the innermost planet, charbroiled Mercury. To outlive the short-lived Venera probes, your rambling sojourn on Venus would presumably include unimaginably strong insulation as temperatures push toward degrees Fahrenheit Celsius.
You would need an extremely thick, pressurized outer shell to avoid being crushed by the weight of the atmosphere — which would press down on you as if you were 0.
The atmosphere is mostly carbon dioxide — the same gas driving the greenhouse effect on Venus and Earth — with clouds composed of sulfuric acid. And at the surface, the hot, high-pressure carbon dioxide behaves in a corrosive fashion. But a stranger transformation begins as you rise higher. Temperature and pressure begin to ease. Even though Venus is similar in size to Earth and has a similar-sized iron core, the planet does not have its own internally generated magnetic field.
Instead, Venus has what is known as an induced magnetic field. This weak magnetic field is created by the interaction of the Sun's magnetic field and the planet's outer atmosphere. Ultraviolet light from the Sun excites gases in Venus' outermost atmosphere; these electrically excited gases are called ions, and thus this region is called the ionosphere Earth has an ionosphere as well.
The solar wind — a million-mile-per-hour gale of electrically charged particles streaming continuously from the Sun — carries with it the Sun's magnetic field.
When the Sun's magnetic field interacts with the electrically excited ionosphere of Venus, it creates or induces, a magnetic field there. This induced magnetic field envelops the planet and is shaped like an extended teardrop, or the tail of a comet, as the solar wind blows past Venus and outward into the solar system.
A 3D model of Venus. Venus and Earth are often called twins because they are similar in size, mass, density, composition and gravity. The interior of Venus is made of a metallic iron core that's roughly 2, miles 6, km wide. Venus' molten rocky mantle is roughly 1, miles 3, km thick. Venus' crust is mostly basalt, and is estimated to be 6 to 12 miles 10 to 20 km thick, on average. Venus is the hottest planet in the solar system. Although Venus is not the planet closest to the sun, its dense atmosphere traps heat in a runaway version of the greenhouse effect that warms Earth.
As a result, temperatures on Venus reach degrees Fahrenheit degrees Celsius , which is more than hot enough to melt lead. Spacecraft have survived only a few hours after landing on the planet before being destroyed.
With scorching temperatures, Venus also has a hellish atmosphere , that consists mainly of carbon dioxide with clouds of sulfuric acid and only trace amounts of water. Its atmosphere is heavier than that of any other planet, leading to a surface pressure that's over 90 times that of Earth — similar to the pressure that exists 3, feet 1, meters deep in the ocean. Incredibly, however, is that early in Venus' history, the planet may have actually been habitable , according to models from researchers at NASA's Goddard Institute for Space Studies and other studies.
Venus' surface is extremely dry. During its evolution, ultraviolet rays from the sun evaporated water quickly, keeping the planet in a prolonged molten state. There is no liquid water on its surface today because the scorching heat created by its ozone-filled atmosphere would cause water to immediately boil away. Related: Inside the Planet Venus Infographic. Roughly two-thirds of the Venusian surface is covered by flat, smooth plains that are marred by thousands of volcanoes, some of which are still active today , ranging from about 0.
Six mountainous regions make up about one-third of the Venusian surface. One mountain range, called Maxwell, is about miles km long and reaches up to some 7 miles Venus also possesses a number of surface features that are unlike anything on Earth. For example, Venus has coronae , or crowns — ring-like structures that range from roughly 95 to 1, miles to km wide.
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