You can't blame astronomers for feel a bit covetous of our erratic neighbor, because when it comes to strange fact about Venus, it genuinely outdoes the rest of the solar system. While we spend a lot of clip worrying about climate alteration on Earth, Venus is already last through a "runaway glasshouse effect" on a terrify scale. It's much name Earth's twin because of their alike sizing and pot, yet if you were to stand on the surface of Venus, you wouldn't bump a paradise; you'd bump a hellscape where the solemnity is really somewhat potent than ours, the air pressing is crushing, and it's hot plenty to dissolve lead. But the unfamiliarity doesn't stop thither. This satellite has a dim rotation that's really backwards liken to most others, a thick cloud layer that's still and however, and a surface that hasn't been see by human optic since the 1980s. It's a reality that resist the prescript of physic and biology as we know them, offering up a roll of planetary oddities that make it one of the most fascinating target in our night sky.
A Day Is Longer Than a Year
Most planets spin on their axes and complete a day's rotation in less time than it takes to revolve the sun. Take Mercury: it zips around the sun in just 88 days but take nearly 176 Earth days to whirl erstwhile on its axis. Venus, however, does the accurate opposite. A individual day on Venus - defined as the time it takes for the satellite to rotate erstwhile proportional to the sun - is really long than its orbital year. It occupy 243 Earth day for Venus to dispatch one revolution, but a mere 225 years to circle the sun. That means if you had the stamina to go the roughshod warmth on the surface, you could observe two sunrises every morning without even revolve, fundamentally living in "fast-forward" congeneric to the remainder of the solar scheme.
A True Counter-Rotator
What do Venus yet weirder is the way it spins. While most planet in our solar scheme rotate counter-clockwise as viewed from above the North Pole (like an egg spinning on its end), Venus is singular in its retrograde gyration, or clockwise. Moreover, its rotation is so slow that the sun would really uprise in the west and set in the east. This is due to an ancient hit with a massive object that disrupted its spin zillion of days ago, or maybe a dim drag from its midst, heavy atm. This backward twirl make a phenomenon known as a "day-night round" that takes months, meaning it can be "daytime" on one side of the planet for month while the other side is stick in total darkness for an evenly long period.
The Atmosphere is Alive and Static
One of the most elusive aspects of Venus is its cloud layer. Unlike Earth, where winds can change from composure to hurricane force, the upper atmosphere of Venus is inactive. The winds on the equator movement at a careen 360 kilometers per hour (220 mph), but the clouds themselves fundamentally abide bushel in place. This creates a eccentric fantasy: while the satellite spin backwards, the cloud tops look to revolve forward at the same speed, entail they essentially rest beneath the sun while the planet spins around them. This is such a potent clash that it actually slows down the satellite's gyration still further, acting like a cosmic bracken.
| Planet | Rotation Speed at Equator | Day Length (Earth Days) |
|---|---|---|
| Venus | ~6.5 km/h (6.4 mph) | 243 |
| Earth | 1670 km/h (1037 mph) | 1 |
| Jupiter | 45,300 km/h (28,000 mph) | 9.9 |
Surface Pressure: The Crushing Weight of Air
If you decided to endure the origin into the Venusian atmosphere, the inaugural thing you'd observance isn't the temperature, but the weight of the air pressing against your body. The atmospheric pressure on the surface is rough 92 time that of Earth's atmosphere. To put that in position, standard atmospherical pressure at sea tier on Earth is 14.7 psi. On Venus, you would be under pressing equivalent to diving a submarine about 900 meter deeply into the ocean. This crushing weight would crush any unpressurized human habitat instantly. It's so thick that if you were stand on Venus, the air itself would be heavy plenty to bump the wind out of you and would experience like you are submerge in water.
Diagram: Envisage a dive bell. The air pressure outside is alike to pushing that bell downward to 900 metre of water depth.
It's Hotter Than Mercury Despite Being Further Away
A classic scientific misconception is that because Venus is far from the sun than Mercury, it should be cooler. The world is that Venus is the hot planet in our solar scheme, hotter even than Mercury. The temperature on Venus averages a scorching 465°C (869°F), hot plenty to dissolve pb and zinc, and glassful would soften if you brought it down there. This utmost warmth is not caused by proximity to the sun, but by that runaway greenhouse result. The thick carbon dioxide atmosphere snare warmth fantastically efficiently. While Mercury whips around the sun and experiences dramatic temperature displacement between nighttime and day because it lacks an atmosphere, Venus gets blasted by constant radiation that ne'er escapes, keep the surface always toasty.
It Does Not Spin Like a Rock
Physicists use to think that Venus was a solid, rigid body like Earth and the Moon. Nonetheless, late datum from NASA commission, like Magellan in the 1990s, suggested that Venus spins more like a fluid - a pasty liquidity or even a planetary hoop. Because its rotation is so slow and it lacks a liquid outer core, it doesn't have a potent magnetised battleground. Globe has a magnetic battleground because our rotating limpid iron core enactment like a giant dynamo. Without this magnetised shield, Venus is at the mercy of solar wind, which strip away atmosphere and bombard the surface with radiation, contributing to its hostile environment.
Noctilucent Clouds with a Glow
Because the clouds on Venus are do of sulfuric acid droplets and reflect sunlight so bright, astronomer can distinguish the satellite from Earth using the naked eye. However, there is a strange phenomenon called "phosphene", a glow atmospherical emission that can sometimes be detected. Despite the utmost brightness of the day side, the night side of Venus is really visible with optical aid because the planet is border by a thick haze of eminent, cold clouds that reverberate sunlight even when the surface is in shadow. This makes Venus the vivid natural target in the dark sky after the Moon, oftentimes outshine Jupiter despite being much farther off.
Death of the Soviet Probes
Venus hasn't been variety to humankind's robotic emissary. While the United States has had some success with orbiters and landers like Magellan and the Pioneer Venus broadcast, the Soviet Union consecrate a massive sum of imagination to exploring the satellite, direct over a 12 probes into the atmosphere. Almost all of them met a grim luck, either burning up in the upper atmosphere or crash on the surface. One of the most iconic was the Venera plan, which establish the first successful landers. Most landed and transmitted information for only a few min before succumbing to the heat, but they provided the alone close-up images of the alien landscape, revealing a barren, desolate existence of jagged stone and backbone.
Its Day is Longer Than Its Year
It's worth circulate backward to this because it remains one of the most bizarre spacial anomaly in our cosmic neighborhood. While a year on Venus is 225 Earth days, a individual day - meaning the time it takes for the planet to revolve fully on its axis so the sun returns to the same perspective in the sky - is 243 Earth day. This mean a Venusian twelvemonth is really shorter than a Venusian day. This is true for almost no other satellite in the solar system. Essentially, if you lived on Venus, you would have to expect about 1.4 Earth years just to experience one total sunrise-to-sunrise rotation.
The Sulfuric Acid Rain
The weather patterns on Venus are textbook fantasy literature. The cloud on Venus are create of a intermixture of sulfuric vitriolic droplets and are implausibly reflective, get the planet play. At the cloud crown, the press and temperature are roughly alike to Earth's, making them theoretically inhabitable, but as you descend, the atmosphere turn thick and hotter. The sulphuric acid clouds do rain, but they don't reach the surface. The cloud evaporate before they can hit the ground due to the vivid heat. This create a "heat rhythm" rather than a precipitation cycle, where the sunshine hit the clouds create vigor that drive massive wind that ne'er touch the soil.
A Planet with 8 Billion Lives, But Not Yours
If you could strip away the warmth, the pressing, and the sulphuric acid cloud of Venus, you might be surprise to happen that the geologic composition of the satellite is somewhat like to Earth's. Scientists believe that Venus could erstwhile have had swimming h2o on its surface. Still, because of the runaway greenhouse effect, that h2o boil out into the atmosphere and photodissociated into hydrogen and oxygen. The hydrogen blow away into infinite, and the oxygen bonded with surface rocks, leaving behind a dry, hot husk. This geologic account makes Venus a macabre monition for clime scientists canvas Earth's current flight.
Frequently Asked Questions
From the shell atmospherical press to the slow, feebleminded spin of the planet itself, Venus remain a mysterious and hostile world that function as a reminder of how delicate our own atm is. It's a spot where the law of aperient seem to take a holiday, offering up a landscape that is both eerily familiar in composing and entirely foreign in appearance.