Venus can be depicted as 'hell', with impenetrable sulfuric acid cloud lying a surface hot enough to melt lead (element) as it's hotter than the Earth as it's nearer to the Sun. All spaces probes to have reached that surface have either instanlty or after a short time been crushed like flies by the tremendous weight of the Venusian atmosphere, 100 times thicker than the Earth'. Yet, paradoxically, Venus is the Earth's twin for having similar composition, a similarily thatspurred sci-fi writters to imagine Venus as a steamy tropical world.
It's comosed of:
Carbon dioxide 96.4%
Nitrogen 3.4%
Sulfur dioxide 0.015%
Argon 0.007%
Water vapor 0.002%
Like Earth, Venus has both night and day. But, the length of the day is much longer than its day on Earth, and it rotates in the opposite direction.
Ultraviolet light reveals cloud patters in the atmosphere of Venus, which is almost featureless at visible wavelengths.
This combination of day and night observations show a spiral cloud pattern encirclling the Venus' south of pole. Ultraviolet imagery shows stripes in the atmospheres of Venus, possibly due to suspended dust and aerosols.
Danivola is a huge impact crater with a bright halo of ejecta and prominent central peak.
A crescent Venus, close to quarter phase, vieweed by the Pioneer Venus 1978 Orbiter.
It's sometime questioned as to why so much is spent on planetary exploration. Venus provides one answer. The "hell" planet is a sober warning to us all. If more carbon dioxide is pumped from the burning of fossils fuels into Earth's atmosphere, Venus is our future.
Venus is deemed to have started out like Earth. But being nearer the Sun made it hotter, water was driven into its atmosphere. Water vapor is a greenhouse gas trapping heat. It boosted Venus' tempearture, which evaporated more water vapor, boosting the temperature yet more, and so on. Eventually, this runaway greenhouse effect led to the oceans boiling away entirely.
This wasn't the end of the climatic crisis. At atmosphere's crust, ultraviolet light fromthe Un splut apart water molecules into their constituent hydrogen and oxygen atoms, gas floated away intp into spaces. Without water, carbon dioxide, pumped out by Venus' volcanoes could not be rained out. A greenhouse gas ike water vapor, it built up , creating an atmosphere a hundred times denser than ours.
On Earth, if more carbon dioxide is injected into the atmosphere, the temperature will go up and the ocean will vanish, like on Venus. Earth has exactly the same amoutn of carbon dioxides as aVenus, but locked up in chalk cliffs. If rising tempeartures bubble all of that out into the air, the Earth will become entirely like Venus. With the green house effect, Venus' lack of water ash other serous iimplication for itself.
Although, Venus, 2 km deep down, may have water.
Venus is permanently shrouded in impenetrable sulfur acid clouds, meaning we can't see the surface of the nearest planet to Earth, except by radar.
Unlike visible light, radio waves go through clouds unhindered. If the echoes are picked up, its possible to use them, with some computer wizardry to bult up a radar image of the hidden surface, which was triumphantly achieved by the "synthetic aprture radar" of NASA' Magellan spacecraft, which orbited the planet from 1990-1994. There are also volcanoes, 50k of them.
Earth's crust is thick and volcanoes break the surface only at certain locations, like tectonic plate boundaries or on the seafloor, which is thin. Venus seems to have no moving plates, only a globally thin crust that lava can puncture almost anywhere. It doesn't have plate tectonics as the planet lacks water.
Roughly, a tiny black disk of Venus can be seen every 120 years in front of the Sun, which occurs twice, 8 years apart.
2004 image showing Venus in front of the Sun in the same year.
Venus it the easiest planet to spot in nighttime. A superbright white light, outshoe only by the Sun and Moon, it's visible just before the Su rises or after it sets. HEnce it is commonly known as the morning or evening star. Other planets are also easy to spot as they were generally brighter than stars. Mars is red, Jupiter white and Saturn a bit yellow.
All planets' orbit are almost in a single planet called the "ecliptic." People have joined the dots of thestars along this zodiac to create 12 signs, like Cancer and Aries.
The word "planet" means "wanderer", a recognition by ancient sky watchers that there is something peculiar about them: they wander against the background of fixed stars.
Each night, planets move across the backdrop of stars, like for Jupiter, moving from the Taurus Constellation to Gemini.
Planets farther from the Sun than Earth, like Mars, can appear to revolve as Earth "catches up" to it.
revolving: rotate on its own