Venus
Venus
Venus is the second closest planet to the sun, and was named after the Roman goddess called Venus. It is in a category called terrestrial planets, this means that it is very similar in size and was created close to the same way as our planet Earth. In fact, sometimes it is called Earth's "sister planet" as they are somewhat alike in both size and roughly a similar distance
- Venera 7, the first space probe to land on Venus, was put out of action by the hostile conditions on Venus after only 23 minutes.
- With a few exceptions, the surface features on Venus are all named after women.
- A day on Venus is longer than a year there.
Venus Facts:
How big is Venus
Venus is very close in size to earth and with a diameter of about 12,100 km or almost 95% of the size of the Earth. This is one of the reasons why Venus is often considered to be the "twin" to the Earth. It is also made up of very similar minerals to those found on the Earth.
What is its surface of venus like?
Venus has a very interesting surface. It is very, very dry and also hot enough to melt lead on its surface. We could not survive on the planet because of this. Anyone attempting to walk on the surface of Venus would boil to death, be squashed flat by the air pressure, and then have their remains eaten away by the corrosive atmosphere. Dispite all of this, there are some features on the surface of Venus that are surprisingly similar to features on the Earth.
River-like channels have been formed on Venus. It is believed that these channels are formed from erupting lava that takes a long time to cool down, and flows down into the lower elevation areas of Venus. Similar rivers of lava have been seen in Hawaii and other volcanoes on the Earth, but the longest of these lava channels on Venus is over 7,000 km long and sometimes as wide as one to two km. That is by far longer than any river on the Earth, including the Nile, Amazon, or Mississippi rivers!
One of the more unusual features to Venus that seems to be unique only to Venus so far is what are called arachnoid volcanoes, or simply arachnoids. When scientists first saw images of these features, it reminded them of pictures of spiders or ticks, although these features were hundreds of kilometers across. These are volcanoes that due to the environmental conditions on Venus have formed very differently from other known volcanoes throughout the rest of the Solar System. The exact process that formed these is still not completely known and an area of future exploration on Venus.
Other more normal volcanoes have been found on Venus as well, and the interior of Venus appears to be almost as active as the interior of the Earth. Almost 90% of Venus's surface is made up of recently-solidified basalt lava, meaning that Venus has experienced a lot of volcanic activity from time to time. The oldest parts on Venus are thought to be only around 800 million years old.
Parts of the surface of Venus appear to be structurally similar to continents on the Earth, with the largest of these called Istar Terra, named after the Babalonian equivalent of Venus. Deep basins like the ocean basins on the Earth have also been discovered, except that they are totally empty of water. Features like mountain ranges and Meteor craters have also been found on Venus. One of its highest mountains, named the Maxwell Montes, is roughly 2 km taller than Mount Everest. Because Venus has a very thick atmosphere, meteors slow down as they fall toward it's surface, so no craters that are smaller than about 3.2 km round can form, according to current theories, and none have been discovered.
Is there life on Venus?
When astronomers first tried to make observations of Venus, they thought that Venus would have a very Earth-like environment, although slightly warmer than the Earth. Venus is almost the same size as the Earth, and covered with clouds, and it was assumed that these might be water clouds like are found here on the Earth.
Many stories written during this time described Venus as having a swamp-like environment, but still something that people could go and visit someday, and even live on. Sometimes exotic aliens were thought to live on Venus, just like people thought the same thing about Mars.
The debate on whether there were living things on Venus continued until robotic spacecraft traveled to the surface of Venus and directly measured the thickness of the atmosphere, what chemicals it contained, and the temperature. The environment on Venus is deadly to almost any living thing on Earth, and it is unlikely that manned exploration of its surface will ever happen. Spaceships that land on Venus must be very strong in order to work with the very high atmospheric pressures on its surface, and to withstand the acids in the atmosphere. One of the gases found on the surface is Sulfuric Acid, which is the same chemical that is used in car batteries, and very toxic if you eat or breathe it. There are many other chemicals that are just as deadly if you were to breathe them in.
Phases of Venus
After telescopes were invented, one of the very first places that they tried to study was Venus. Even with a modest telescope this is a fairly easy feature to identify. Just like the Earth's Moon has phases during different times of the month, Venus also appears to go through similar kinds of phases where it appears in a crecent shape during some parts of its orbit around the Sun. This visual appearance is caused because Venus is closer to the Sun than the Earth, and we are looking at the night sky of Venus, or the part of Venus that is facing away from the Sun.
This is slightly different than the phases of the Earth's Moon, because the distance between the Earth and Venus varies quite a bit. When Venus is at its closest point to the Earth, it appears as a thin crecent or even can't be seen at all. Only when Venus is almost at a location furthest from the Earth can a full disk be seen through a telescope.
Sometimes on rare occasions, Venus actually crosses directly between the Sun and the Earth. This is called a transit, which is very similar to a solar eclipse by the Earth's Moon. Many early details about Venus were discovered this way, including approximately how large Venus was, and the fact that it had an atmosphere due to how "fuzzy" the outline of Venus was against the Sun. During a transit of the Sun, Venus appears as a small circle going across the Sun's photosphere
What is Venus moon like?
Early in history Venus was once thought to have a moon, named Neith after the mysterious goddess of Sais. The moon was first seen by Giovanni Domenico Cassini in 1672. Astronomers saw this moon from time to time until 1892, until they found out their sightings were mostly faint stars that were in the right place at the right time. Venus is now known to be moonless.
Venus's rotation is so slow that if Venus had a moon, it would crash into the planet or get broken up. This would happen because the moon's gravity would cause tidal effects on Venus, which would create two bulges called tidal bulges on Venus. One would bulge toward the moon, with the other bulge being on the opposite side of Venus. The moon's motion in its orbit would be faster than Venus's very slow rotation. That would cause the moon to be ahead of the tidal bulge all the time. The gravity from the bulge would pull back on the moon. This would pull the moon closer to Venus and make Venus's rotation speed up. This would continue to happen over millions of years until the moon got broken up by Venus's gravity or crashed onto Venus. Venus has existed for billions of years, so if it had any moon, it is long gone.
How long is a day on Venus?
Venus rotates even more slowly than Mercury. One siderial day on Venus is about 243 Earth days long. This is the time it takes for a distant star to go from being directly overhead to being above you again. One solar day on Venus is about 117 Earth days long, or the time it takes for the sun to be over one spot on Venus to returning to that same position. The reason for this difference is that Venus is also going around the Sun at the same time it is turning. There is a difference between sideral and solar days on the Earth as well, but because the Earth is spinning so quickly compared to Venus it is only a difference of a few minutes each day instead of over a hundred days like it is on Venus.
It also rotates the opposite direction from most of the planets in the Solar System. This is called retrograde motion, where the Sun rises in the west and sets in the east, from the viewpoint of somebody standing on the surface of Venus.
This rotation period is also rather unusual because of an interesting coincidence with this orbital period and the Earth. Venus always seems to have the same side of its planet facing the Earth as it passes close to the Earth, almost as if Venus had a tidal lock on the Earth like the Earth's Moon. From the perspective of somebody standing on Venus, Earth would always be in the same spot in the sky year after year. What causes this behavior from Venus is totally unknown, and may be a pure luck, but many scientists often discover new ideas by studying a coincidence like this.
How long is a year on Venus?
One Venus year is 224.7 Earth days long. So, one Venus day is longer than one Venus year. There is an interesting coincidence with this period of time as well, because from one conjunction between the Earth and Venus to the next one (when the Earth and Venus are closest together and on the same side of the sun) is 584 days. What is unusual about this number is that it happens five times every eight years on the Earth, in a pattern that is very close to the same orbital time period of the Earth around the Sun.
5 x 584 (Earth days between conjunction of Earth and Venus) = 2920 days
8 x 365 (Earth days in an Earth year) = 2920 days
This was known to ancient astronomers and played an important part in the design of many ancient calendars, including some eight year cycles where the pattern that Venus followed in the sky was watched very closely. There is no current scientific theory to explain this coincidence other than it just happened to be like this.
What is Venus made of?
Like Earth, Venus appears to have class=""have a crust and mantle made of silicates and an iron core. There are a number of features on the surface of Venus that resemble features found on the Earth, so it is likely that many of the internal characteristics of both the Earth and Venus are the same.
How much would Venus's gravity pull on me?
If you were on Venus, it would pull you down with a force about nine tenths as strong as the force of Earth's gravity. In terms of the effect of gravity when on the surface of Venus, it is almost identical to what happens to objects and people when they are on the Earth.
What is the future for exploring Venus?
Because Venus is so close to the Earth, and reveals many clues regarding how the Earth works, it is going to be studied even closer in the future. There are several proposals to have spacecraft travel to Venus and then deploy a balloon that would allow scientific intruments to travel in the atmosphere. In fact, two of these have already been sent to Venus, called Vega 1 and Vega 2. These Russian spacecraft measured the composition of the atmosphere of Venus and relayed other important scientific information. There are plans now for even more advanced spacecraft, with perhaps even a motor on the balloon that would turn the spacecraft into an airship. In some very far reaching proposals there is a suggestion that perhaps a high-altitude balloon could even have people on board. Scientists studying Venus could live high in the clouds where the atmosphere isn't nearly so hazardous to people, with research being performed in a manner similar to how scientific research is currently conducted in Antarctica right now.
Can Venus be Terraformed?
An interesting debate is occuring right now about the possibility of Venus being changed into conditions similar to what the Earth is like right now. That is called Terraformation, or the formation of Earth-like worlds. While in theory it could be done, it would require incredible financial resources in order to accomplish, and there are some people who even question if it should even be done at all. While the concept is largely something science fiction authors talk about, it is a topic that is now beginning to enter into discussions with scientists who study this planet, at least in terms of speculating just how such a task might be accomplished. It is also argued by some scientists that we on the Earth are doing the opposite and Venusforming the Earth with pollution and the release of greenhouse gasses, turning the environment of the Earth to be more like Venus. Certainly the ideas that would be gained from trying to figure out how to increase the absorbtion of greenhouse gasses that make Venus so hot and inhospitable to life can have long term positive benefits for people here on the Earth.
Who is Venus named after?
Venus is named after the Roman goddess of love. It looked bright in the sky sometimes, so it was named after the beautiful goddess. The planet Venus is also associated with the Greek goddess Aphrodite, as well as Frigg and Freya in Norse mythology. Indeed, almost every ancient culture associated the planet with a major deity, although not all of them were female. An example of the planet being named after a male diety is Tlahuizcalpantecuhtli, one of the Aztec gods, together with his brother Xolotl. In Aztec society the morning and evening stars were considered seperate dieties rather than the same object as Greek and Roman societies thought of them.