It’s a cloud-swaddled planet named for a love goddess, often called Earth’s twin. But pull up a bit closer, and Venus turns hellish. Our nearest planetary neighbor, the second planet from the Sun, has a surface hot enough to melt lead. The atmosphere is so thick that, from the surface, the Sun is just a smear of light.
In some ways it is more an opposite of Earth than a twin. Venus spins backward, has a day longer than its year, and lacks any semblance of seasons. It might once have been a habitable ocean world, like Earth, but that was at least a billion years ago. A runaway greenhouse effect turned all surface water into vapor, which then leaked slowly into space. The present-day surface of volcanic rock is blasted by high temperatures and pressures. Asked if the surface of Venus is likely to be life-bearing today, we can give a quick answer: a hard “no.”
Further, Venus may hold lessons about what it takes for life to get its start . On Earth, in our solar system, or across the galaxy. The ingredients are all there, or at least, they used to be. By studying why our neighbor world went in such a different direction with regard to habitability. We could find out what could make other worlds right. And while it might sound absurd, we can’t rule out life on Venus entirely. Temperature, air pressure, and chemistry are much more congenial up high, in those thick, yellow clouds.
Are you interested to know more about Venus – atmosphere and potential for life? Check out relevant information provide by Pritish Kumar Halder below:
Venus’ atmosphere is one of extremes. 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 900 degrees Fahrenheit. 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 0.6 miles deep in the ocean.
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.
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. 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.
Potential for Life
Thirty miles up (about 50 kilometers), temperatures range from 86 to 158 Fahrenheit (30 to 70 Celsius), a range that, even at its higher-end, could accommodate Earthly life, such as “extremophile” microbes. And atmospheric pressure at that height is similar to what we find on Earth’s surface.
At the tops of Venus’ clouds, whipped around the planet by winds measured as high as 224 miles per hour. Persistent, dark streaks appear. Scientists are so far unable to explain why these streaks remain stubbornly intact, even amid hurricane-force winds. They also have the odd habit of absorbing ultraviolet radiation.
The most likely explanations focus on fine particles, ice crystals, or even a chemical compound called iron chloride. Another possibility considered by scientists who study astrobiology is that these streaks could be made up of microbial life, Venus-style. Astrobiologists note that ring-shaped linkages of sulfur atoms, known to exist in Venus’ atmosphere. This could provide microbes with a kind of coating that would protect them from sulfuric acid. These handy chemical cloaks would also absorb potentially damaging ultraviolet light and re-radiate it as visible light.
Some of the Russian Venera probes did, indeed, detect particles in Venus’ lower atmosphere about a micron in length. Roughly the same size as a bacterium on Earth.
None of these findings provide compelling evidence for the existence of life in Venus’ clouds. But the questions they raise, along with Venus’ vanished ocean. Its violently volcanic surface, and its hellish history, make a compelling case for a return to our temperamental sister planet. There is much, it would seem, that she can teach us.
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.
Venus was the first planet to be explored by a spacecraft. NASA’s Mariner 2 successfully flew by and scanned the cloud-covered world on Dec. 14, 1962. Since then, numerous spacecraft from the U.S. and other space agencies have explored Venus. Including NASA’s Magellan, which mapped the planet’s surface with radar. Soviet spacecraft made the most successful landings on the surface of Venus to date. But they didn’t survive long due to the extreme heat and crushing pressure. An American probe, one of NASA’s Pioneer Venus Multiprobes, survived for about an hour after impacting the surface in 1978.
Click here for other structural and formation related information about Venus.