Venusearthpassage - SpaceTransit

Emil Ivanov - When Venus Rises with the Sun, 2012. (View across the Black Sea on June 6 finds Venus rising with the Sun)   

Moon - Venus - Mars

by Neil A.D. Taylor

Shared from Sky News: Venus has more volcanoes than we thought - and this map shows where they are

Sky News

Venus has more volcanoes than we thought - and this map shows where they are

The findings come ahead of new NASA and European Space Agency missions to uncover more mysteries of a planet described as "Earth's twin". Th

Wind hitting Venus’s mountains makes the planet rotate faster

Turbulent atmosphere speeds Venus’s days by a full 2 minutes

Venusian mountains impact its rotation

I do love me a good artist drawing of the Solar System. This time with moons and more facts! Art by Vadim Sadovski.

The Surprisingly Strong Case For Colonizing Venus:

Why worry about building a colony on Mars when instead you could float one high above the surface of Venus? Science fiction writer Charles Stross recently revived the idea of building a Venutian colony when he suggested, cheekily, that billionaires ought to be compelled to donate to massive humanity-improving projects. He suggested two: a Manhattan Project-like focus on developing commercial nuclear fusion, or the construction of a floating city on Venus. 

The second planet from the Sun might seem like a nasty place to build a home, with a surface temperature hot enough to melt lead and an atmosphere so dense it would feel like being submerged beneath 3000 feet of water. But the air on Venus thins out as you rise above the surface and cools considerably; about 30 miles up you hit the sweet spot for human habitation: Mediterranean temperatures and sea-level barometric pressure. If ever there were a place to build a floating city, this would be it.

Believe it or not, a floating city might be a feasible project. Scientist and science fiction author Geoffrey Landis presented a paper called “Colonizing Venus” [PDF] at the Conference on Human Space Exploration, Space Technology & Applications International Forum in Albuquerque, New Mexico back in 2003. Breathable air floats in Venus’s soupy carbon dioxide atmosphere, which means on Venus, a blimp could use air as its lifting gas, the way terrestrial blimps use helium to float in our much thinner atmosphere.

This figure shows the volcanic peak Idunn Mons in the Imdr Regio area of Venus. The topography derives from data obtained by NASA’s Magellan spacecraft, with a vertical exageration of 30 times. Radar data (in brown) from Magellan has been draped on top of the topographic data. Bright areas are rough or have steep slopes. Dark areas are smooth. (NASA/JPL/ESA)

A group of science fiction authors and scientists have been discussing the idea on the blog Selenian Boondocks, which founder Jonathan Goff describes as “a blog I founded to discuss space politics, policy, technology, business, and space settlement.” One of the biggest problems with a lunar or Martian colony is that an astronaut’s bones and muscles deteriorate in low gravity. No one knows yet how much gravity a human needs to prevent deterioration, but Venus’s gravity is the closest to Earth’s, at about 9/10ths. Mars only has a third of the gravity that the Earth does, while the moon has a mere sixth.

Atmospheric pressure is also crucial. Think of the difference between jabbing a car tire and letting air out of a half-inflated balloon. Gases seek equilibrium. Since there’s barely any atmosphere on the moon or Mars, a rip in the hull of an enclosed human habitat would suck oxygen out at tremendous force. Thirty miles above Venus, it would merely seep out. This also means a Venutian cloud colony wouldn’t need as much reinforcement. Venus has other boons, too. Its rich atmosphere blocks radioactivity and could be mined for useful materials. And with a gentle temperature, far less energy would have to be spent on heating or cooling the colony.

Of course, it’s hard enough landing on the surface of another planet, let alone at 30 miles above the surface, but Landis hypothesized a way to do it.

A hypothetical floating outpost 30 miles above the surface of Venus. (Wikimedia Commons/Anynobody)

A sphere with titanium skin 0.04” thick would be able to survive reentry and float a couple of miles above the surface, he argued. Goff, who who describes himself as a space entrepreneur and space settlement advocate, suggests that rocket stages (the parts that drop off of a spaceship during liftoff) could also be engineered to float after use and be re-used, providing a way to and from the colony so that building materials could be mined from the surface. The well-informed space enthusiasts who frequent the Selenian Boondocks also helped Goff map out the chemical processes required to extract breathable air (a mixture of nitrogen and oxygen), water and various fuel and construction materials. 

After the chemical processes involved with producing life-supporting materials are demonstrated and perfected, the Selenian Boondocks team suggest small robotic labs could be sent to Venus, where they would bob in the atmosphere, extracting life-sustaining materials, gradually inflating great bladder-like structures (perhaps a Bigelow Aerospace module made of Kevlar). Years into the project, it might look like a gargantuan bunch of grapes. Permanent settlers could tether these floating blobs together, extending walkways and building platforms, creating something that might eventually look like a massive floating oil rig, complete with tubes dangling dozens of miles below to gather materials from the surface.

Goff plans to continue fleshing out the details on his site over the coming months (plans were temporarily put on hold after the birth of his youngest child). “I still need to talk about chemicals that seem easy to get to from the raw materials,” he says, “and how those impact colony design.”

As to what life perched high above Venus might really feel like, frequent Selenian Boondocks commentator George Turner imagines how a tough colonist might dangle meat into Venus’s ferocious, acidic atmosphere as a cooking source:

Well let me tell you, acid is good for meat, and breaks down connective tissue, fats, and tenderizes it. Run the pH the other way and it turns into soap and you might as well bite into a urinal cake.

Venus is not for the timid, or people too afraid to shove a fat bird out the airlock and let the harsh laws of thermodynamics do the work. Venus is for men. Men who like to eat meat – cooked in fire and acid and seasoned with the Devil’s own mix of volatiles boiled up from the pits of hell.

If the thought of Thanksgiving Dinner on Venus gives you the heebie jeebies, you don’t even need to think about plunging into the roiling atmosphere with nothing but a cheap plastic heat shield and a thin balloon to save you from the crematorium that yawns down below. So man up, dangle the bird into the depths of the Stygian hell, feast as someone who walks between worlds and lives on an airship that rides the hell born winds 30 miles above a surface so hot it glows visibly red.

Ultimately there will have to be a compelling reason to spend trillions of dollars to move off-world: a vital resource located on Venus, mass over-crowding, nuclear apocalypse. But if we do colonize the skies of Venus, it will be the soft factors like the plausibility of a Venutian acid-baked cuisine that will make us stay. 

When it landed on Venus on December 15th, 1970, Venera 7 became the first spacecraft to achieve a soft-landing on another planet. Only able to transmit surface data back to Earth for 23 minutes due to signal degradation, it was determined by Venera 7’s transmission that the atmosphere of Venus is composed 97% of carbon dioxide, with a temperature reading of 887°F (475°C).

Daily Science Dump: Kepler’s First Law Edition

Bonjour my science nerds. I got a question regarding Kepler’s Three Laws because they can be somewhat confusing. And tbh, they really are. Because they can be a bit of a pain, I’ve decided to break this up into 3 sections, one for each law. They generally follow the same idea: planetary orbits are not circular. The difference between each law resides in the minute details. And because they are really detailed, I wanted to make sure I covered everything of each law so they don’t get confused. Let’s get started!

Kepler’s First Law of Planetary Motion

History

Before we get into the actual laws, we need to understand why these laws are so important. During the 1500s and early 1600s, astronomy was starting to become a big deal. We were trying to figure out where we are in the universe. During this time period, the famous geocentric and heliocentric models were stirring up massive controversy in the Catholic Church (for obvious reasons). Ptolemy brought around the geocentric model, which put Earth at the center. This was a natural thought at the time because it was a religious concept that man was God’s greatest creation, so God would want to put man at the center of everything (little presumptuous on our part tbh). Next, Copernicus said that our Sun was in the center, and all the planets orbit around the sun. This clearly didn’t go down well with the Church because it was the first instance of defying the Catholic Church, therefore defying God. In an attempt to settle down the controversy, Brahe brought around a new theory model, putting the Earth at the center, having the Sun and Moon orbiting the Earth, and then the rest of the planets orbiting the Sun. It was a very far reached model but people bought it. All of these models had one thing in common; all the orbits of the planets were circular. But none of none of the actual data fit with perfect circular orbits. This is where our boi Kepler comes in. 

It was long believed that the planets should orbit along circular paths, because a circle is considered an ideal shape. But as I mentioned before, none of the data was fitting the circular shape, particularly Mars. Kepler brought around another shape, the ellipse, to explain the missing pieces of the data. An ellipse is like a flattened circle with some important properties that Kepler used for his laws. His first law focuses more on explaining the patterns of elliptical orbits. The second and third law goes into more detail on the properties of elliptical orbits. 

If you’ve taken a simple geometry class, you know the basic principles of ellipses. We know there’s a major-axis and minor-axis (the diameter horizontally and the diameter vertically), the focal points, and eccentricity. All of these are important for planetary orbits. If we take a trip back to geometry, we know that the positions of the focal points affect the eccentricity, which is basically how much it’s being squished (if e = 0 then it’s a perfect circle and if e = 1 it’s a parabola). 

All of this geometry going on transfers over into planetary motion. In this case, the Sun acts as one of the focal points. The other focal point is merely imaginary. Mathematically it exists but there’s nothing at that point in space that says “Hey! I’m a focal point for Saturn!”. But we know for sure that the Sun is on of the two focal points. This revelation caused a lot of uproar and many refused to believe it. Partly because the orbit of a lot planets are so close to a perfect circle it’s extremely hard to tell it’s elliptical at all. 

Eccentricity has to stay between 0 and 1, like I explained earlier. An eccentricity of 0 is a perfect circle. If it’s 1 or greater, it’s a parabola. For the planetary motion, most of the planets’ eccentricity doesn’t even crack 0.1 (Pluto has a bit over 0.2 but apparently Pluto isn’t a planet #JusticeForPluto). Earth’s eccentricity is currently 0.0167, which means its very very close to a perfect circle. But not quite. To be quite honest, the fact that Kepler was able to figure out that the orbits were not circular is astonishing.

So that’s it for Kepler’s First Law of Planetary Motion! These laws were critical in understanding how our universe works and how our solar system plays out. It opened our eyes to many new ideas and thought processes. This law is just the first step of understanding the orbital tendencies of planets. On Friday, we will dive right into Kepler’s Second Law of Planetary Motion which goes into detail about the speed of the planet due to the elliptical orbit.

Don’t forget, I’m updating the Blog Website everyday with something new because I have no life…. I added cool space music! If you have any cool song recommendations for the playlist definitely shoot me a message!

If you have any questions about today’s Daily Science Dump or any past ones, don’t be afraid to ask!

As always,

Stay Nerdy!

R.L.

Ten Interesting facts about Venus

As one of the brightest objects in the sky, Venus has been a major fixture in human culture for as long as records have existed. It has been made sacred to gods of many cultures, and has been a prime inspiration for writers and poets as the “morning star” and “evening star”. Venus was the first planet to have its motions plotted across the sky, as early as the second millennium BC.

Venus is the second planet from the Sun, orbiting it every 224.7 Earth days. It has the longest rotation period (243 days) of any planet in the Solar System and rotates in the opposite direction to most other planets.

It does not have any natural satellites. It is named after the Roman goddess of love and beauty.

It is the second-brightest natural object in the night sky after the Moon, reaching an apparent magnitude of −4.6 – bright enough to cast shadows at night and, rarely, visible to the naked eye in broad daylight.

Venus is a terrestrial planet and is sometimes called Earth’s “sister planet” because of their similar size, mass, proximity to the Sun, and bulk composition.

It is radically different from Earth in other respects. It has the densest atmosphere of the four terrestrial planets, consisting of more than 96% carbon dioxide. The atmospheric pressure at the planet’s surface is 92 times that of Earth, or roughly the pressure found 900 m (3,000 ft) underwater on Earth. Venus is by far the hottest planet in the Solar System, with a mean surface temperature of 735 K (462 °C; 863 °F), even though Mercury is closer to the Sun.

As the closest planet to Earth, Venus has been a prime target for early interplanetary exploration. It was the first planet beyond Earth visited by a spacecraft (Mariner 2 in 1962), and the first to be successfully landed on (by Venera 7 in 1970). Venus’s thick clouds render observation of its surface impossible in visible light, and the first detailed maps did not emerge until the arrival of the Magellan orbiter in 1991. Plans have been proposed for rovers or more complex missions, but they are hindered by Venus’s hostile surface conditions.

Much of the Venusian surface appears to have been shaped by volcanic activity. Venus has several times as many volcanoes as Earth, and it has 167 large volcanoes that are over 100 km (62 mi) across. The only volcanic complex of this size on Earth is the Big Island of Hawaii. This is not because Venus is more volcanically active than Earth, but because its crust is older. Earth’s oceanic crust is continually recycled by subduction at the boundaries of tectonic plates, and has an average age of about 100 million years, whereas the Venusian surface is estimated to be 300–600 million years old.

As it orbits the Sun, Venus displays phases like those of the Moon in a telescopic view. The planet appears as a small and “full” disc when it is on the opposite side of the Sun (at superior conjunction). Venus shows a larger disc and “quarter phase” at its maximum elongations from the Sun, and appears its brightest in the night sky. The planet presents a much larger thin “crescent” in telescopic views as it passes along the near side between Earth and the Sun. Venus displays its largest size and “new phase” when it is between Earth and the Sun (at inferior conjunction). Its atmosphere is visible through telescopes by the halo of sunlight refracted around it.

The Venusian orbit is slightly inclined relative to Earth’s orbit; thus, when the planet passes between Earth and the Sun, it usually does not cross the face of the Sun. Transits of Venus occur when the planet’s inferior conjunction coincides with its presence in the plane of Earth’s orbit. Transits of Venus occur in cycles of 243 years with the current pattern of transits being pairs of transits separated by eight years, at intervals of about 105.5 years or 121.5 years—a pattern first discovered in 1639 by the English astronomer Jeremiah Horrocks.

In 1967, Venera 4 found Venus’s magnetic field to be much weaker than that of Earth. This magnetic field is induced by an interaction between the ionosphere and the solar wind, rather than by an internal dynamo as in the Earth’s core. Venus’s small induced magnetosphere provides negligible protection to the atmosphere against cosmic radiation.

source

images: Mattias Malmer/NASA/JPL, Peter Barvoets,  Soviet Planetary Exploration Program, NSSDC, Marc Lecleire, ESA, C. Carreau,