Normally, that would mean that days on Venus would be longer than years. However, because of Venus' curious retrograde rotation, the time from one sunrise to the next is only about Earth days long. The last time we saw Venus transit in front of the sun was in , and the next time will be in The very top layer of Venus' clouds zips around the planet every four Earth days, propelled by hurricane-force winds traveling roughly mph kph.
This superrotation of the planet's atmosphere, some 60 times faster than Venus itself rotates, may be one of Venus' biggest mysteries. The clouds also carry signs of meteorological events known as gravity waves , caused when winds blow over geological features, causing rises and falls in the layers of air.
The winds at the planet's surface are much slower, estimated to be just a few miles per hour. Unusual stripes in the upper clouds of Venus are dubbed "blue absorbers" or "ultraviolet absorbers" because they strongly absorb light in the blue and ultraviolet wavelengths.
These are soaking up a huge amount of energy — nearly half of the total solar energy the planet absorbs. As such, they seem to play a major role in keeping Venus as hellish as it is. Their exact composition remains uncertain; Some scientists suggest it could even be life , although many things would need to be ruled out before that conclusion is accepted.
The Venus Express spacecraft, a European Space Agency mission that operated between and , found evidence of lightning on the planet, which formed within clouds of sulfuric acid, unlike Earth's lightning, which forms in clouds of water.
Venus' lightning is unique in the solar system. The lightning is of particular interest to scientists because it's possible that electrical discharges from lightning could help form the molecules needed to jumpstart life, which is what some scientists believe happened on Earth.
A long-lived cyclone on Venus, first observed in , appears to be in constant flux , with elements constantly breaking apart and reforming. NASA's Mariner 2 came within 21, miles 34, km of Venus in , making it the first planet to be observed by a passing spacecraft.
The Soviet Union's Venera 7 was the first spacecraft to land on another planet, having landed on Venus in December Venera 9 returned the first photographs of the Venusian surface. The European Space Agency's Venus Express spent eight years in orbit around Venus with a large variety of instruments and confirmed the presence of lightning there.
In August , as the satellite began wrapping up its mission, controllers engaged in a month-long maneuver that plunged the spacecraft into the outer layers of the planet's atmosphere. Venus Express survived the daring journey , then moved into a higher orbit, where it spent several months. By December , the spacecraft ran out of propellent and eventually burned up in Venus' atmosphere.
Japan's Akatsuki mission launched to Venus in , but the spacecraft's main engine died during a pivotal orbit-insertion burn, sending the craft hurling into space. Using smaller thrusters, the Japanese team successfully performed a burn to correct the spacecraft's course. A subsequent burn in November put Akatsuki into orbit around the planet. In , Akatsuki spotted another huge "gravity wave" in Venus' atmosphere.
The spacecraft still orbits Venus to this day, studying the planet's weather patterns and searching for active volcanoes. 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. A 3D model of the surface of Venus. This page showcases our resources for those interested in learning more about Venus. Venus Resources. Ten Mysteries of Venus. JPL's lucky peanuts are an unofficial tradition at big mission events.
Full Moon Guide: October - November A new paper details how the hydrological cycle of the now-dry lake at Jezero Crater is more complicated than originally thought. This year, the minimum extent of Arctic sea ice dropped to 1.
The lander cleared enough dust from one solar panel to keep its seismometer on through the summer, allowing scientists to study three big quakes. Researchers will use Webb to observe 17 actively forming planetary systems. Scientists found evidence that an area on Mars called Arabia Terra had thousands of "super eruptions" over a million-year period.
Scientists think that the massive resurfacing, which took place approximately to million years ago, may have "turned off" any plate tectonics on the planet, completely solidifying the crust into a single surface. The thick atmosphere of Venus also serves to shield it from bombardment even today. Only the largest of meteors make it through the clouds without burning up completely. Venus is a rocky planet, much like the Earth.
Given its similar size, mass, and density to our planet, scientists think that its interior is much like Earth's own. In addition to a crust significantly older than Earth's constantly changing surface, Venus likely also sports a mantle and a core. The mantle is probably rocky, and the core is probably somewhat liquid.
But despite the planets' similarities, the magnetic field of Venus is far weaker than on Earth's. The reasons for that may have to do with the core. Part of it could simply have to do with motion. The planet spins very slowly — once every Earth days — and the core may not spin fast enough to create a magnetic field the way the core of Earth and other planets do.
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