These comments were originally posted to the article “No Doomsday in 2012“. Unfortunately, there were so many comments that it was crashing my webserver every time it posted them.
If you want to comment on the article, you can do it here.
These comments were originally posted to the article “No Doomsday in 2012“. Unfortunately, there were so many comments that it was crashing my webserver every time it posted them.
If you want to comment on the article, you can do it here.
The orbit of Venus is the most circular in the entire Solar System. In mathematical terms, the eccentricity of Venus is less than 0.01. A year on Venus lasts 223 days.
As Venus travels around the Sun, it ranges in distance from 107 million km to 109 million km. The average distance is 108 million km. This is 72% the distance of Earth to the Sun.
Venus can get as close as 40 million km from the Earth. This is called an inferior conjunction every 584 days, on average.
One of the most unusual things about Venus is that it rotates backwards from the rest of the planets in the Solar System. Seen from above, all of the planets rotate counter-clockwise, but Venus turns clockwise. Of course, Venus orbits so slowly that its day is actually longer than its year. A day on Venus lasts 243 Earth days, while its year is 224.7 Earth days.
Our planet is an active world geologically. We have volcanoes constantly erupting across the planet, especially in the regions where plate tectonics are most active. Wherever one plate is sliding against another plate, or one is passing underneath another, you can expect to see volcanoes erupting.
Since Venus is such a hellish world, with incredibly hot temperatures and hot pressures, does Venus have volcanoes?
Venus certainly did have volcanoes in the past. Planetary scientists have identified more than 1,600 major volcanoes or volcanic features on Venus. And there almost too many smaller ones to count. So Venus did have volcanoes.
But does Venus have any volcanoes right now? Unfortunately, we just don’t have enough data to go on. Venus is shrouded in thick clouds of carbon dioxide in its atmosphere, so you can’t have an orbiter easily take photographs of the planet’s surface.
There is no water on the surface of Venus, and scientists know that the planet has no plate tectonics, like we have here on Earth. There are no continents. And so Venus doesn’t have the same regions of volcanism as we have on Earth.
So right now, scientists have no idea if there are volcanoes on Venus. There could be a few spotty regions across the planet, where there is some activity, but none have been seen erupting in the present.
Unfortunately, Venus doesn’t have rings. It also doesn’t have any moons; although, Venus might have had a moon in the past, but it probably crashed back into the planet billions of years ago.
For a planet to have rings, it must have formed further out in the Solar System, where water ice would be able to freeze into chunks of ice. It’s too warm around Venus, so that any water would be a gas or liquid. It would either collect into oceans, like Earth, or be pushed out into deeper space by the Sun’s solar wind.
Another way that planets can have rings is when micrometeoroids smash into a small moon. If the moon is really small, like Pluto’s moon Nix, material ejected from the meteoroid impact will just float off into space and form a ring around the planet. There are several moons around Saturn which create rings in this way, and scientists think that Pluto’s moons might form rings in the same way.
Sorry, no rings for Venus.
Saturn has rings and Jupiter has rings. Does Pluto have rings? Astronomers have no idea. Pluto is so far away that it’s impossible to get a clear view of Pluto from here on Earth.
You can also look through these books from Amazon.com if you want more information about Pluto.
But scientists think that it’s possible that Pluto does have rings. This idea comes from the fact that Pluto has two tiny moons, Nix and Hydra. They’re just a few km across, and have very little gravity. So any micrometeoroid impacts on these moons will kick up material into orbit around Pluto.
Instead of falling back down onto the moons, this impact material would drift into rings around Pluto. Astronomers think it could actually survive for up to 100,000 years. This is a similar process that creates some of the rings around Saturn and Jupiter.
If this is true, it would constitute the first set of rings around a solid object (in this case a dwarf planet), rather than a gas giant planet.
When NASA’s New Horizons mission arrives at Pluto in 2015, it might be able to detect these faint rings, and confirm the theory.
The planet Earth has a slightly eccentric orbit. This means that its distance from the Sun can vary slightly as the Earth travels an elliptical path around the Sun. Pluto has an extremely elliptical orbit, varying its distance dramatically from the Sun dramatically.
You can also look through these books from Amazon.com if you want more information about Pluto.
So the closest distance between the Earth and Pluto occurs when Earth is at its most distant from the Sun, and Pluto is at its closest. And the Sun, Earth and Pluto are lined up in a perfect line. When this happens, Pluto and Earth would be separated by 4.2 billion km.
At their most distant, Earth would be at its furthest at the opposite side of the Sun from Pluto. At this point, Earth and Pluto would be separated by 7.5 billion km.
And so, the distance from Earth to Pluto ranges between these two distances.
The surface of Venus is a hellish place, with vast regions shaped by volcanic activity. In fact, Venus has many more volcanoes than Earth. It has more than 150 regions across the planet shaped by volcanoes.
And from this, you would think that Venus is more volcanic than Earth, but actually, it’s just that the regions of volcanic activity weren’t covered up as they have been here on Earth. The surface of Earth is constantly reshaped by tectonic activity, where plates on the crust of the planet float atop a layer of magma. These plates can slide underneath one another, and any features on the surface are destroyed.
For some reason, plate tectonics on Venus stopped billions of years ago. Planetary scientists think that the high temperatures on Venus shut down the cycle of plate tectonics. Volcanic features created on the planet billions of years ago are still visible, while they would have been obscured long ago on Earth.
Scientists think there is still active volcanism on Venus.
There are more than 1,000 impact craters on Venus, distributed across the planet. While craters are eroded here on Earth, they’re still in pristine condition on Venus. The craters range in size from 3 km to 280 km in diameter.
Of all the planets in the Solar System, Venus has a unique rotation. Seen from above, all of the planets rotate in a counter-clockwise direction. And this is what you would expect if all the planets formed from the same planetary nebular billions of years ago.
And yet, the rotation of Venus is clockwise, what astronomers call “retrograde”. Venus rotates backwards. Of course, since the length of a day on Venus is longer than a year, this rotation happens very slowly.
Why does Venus rotate backwards? One possibility is that Venus rotated normally when it first formed from the solar nebula, and then the tidal effects from its dense atmosphere might have slowed its rotation down.
Another theory is that a series of gigantic impacts early on in Venus’ history might have stopped or even reversed its rotation altogether. A similar impact happened to Earth billions of years ago, which formed the Moon.
We have another new host for the Carnival of Space. This week we look to David S. F. Portree and his blog Altair VI.
Click here to read the Carnival of Space #54
And if you’re interested in looking back, here’s an archive to all the past carnivals of space. If you’ve got a space-related blog, you should really join the carnival. Just email an entry to [email protected], and the next host will link to it. It will help get awareness out there about your writing, help you meet others in the space community – and community is what blogging is all about. And if you really want to help out, let me know if you can be a host, and I’ll schedule you into the calendar.
Finally, if you run a space-related blog, please post a link to the Carnival of Space. Help us get the word out.
Venus is one of the 5 planets visible with the unaided eye. This means that ancient people knew of Venus, and tracked its movements in the sky. Venus is the second planet away from the Sun and is the brightest object in the sky aside from the Moon and the Sun and it appears 10x brighter than the brightest star in the sky, Sirius. The clouds of Venus reflect the light of the sun like a giant mirror.
Venus was named after the Roman Goddess of Love (in Greek, Aphrodite). In ancient times, Venus was known to the Babylonians as Ishtar, the goddess of womanhood and love, so the planet has a long standing tradition of being associated with amore. Furthermore, the symbol for the planet Venus is the symbol for womanhood; a circle with a cross on the bottom.
The ancient Egyptians and Greeks thought Venus was two separate bodies and named them The Morning Star and the Evening Star until in Hellenistic times, people figured out that it was only one object.