[TheZookie007]

Makes Earth's hurricanes and tornados speed seem slow. 

NASA Visualization Explorer, September 2013: "Supersonic Wind"

"Neptune, the eighth and farthest planet from the sun, has the strongest winds in the solar system. At high altitudes speeds can exceed 1,100 mph. That is 1.5 times faster than the speed of sound. In 1989, NASA's Voyager 2 spacecraft made the first and only close-up observations of Neptune. Detailed images taken by the spacecraft revealed bright, white clouds and two colossal storms whipping around the planet's atmosphere. Neptune is a gas giant composed primarily of hydrogen and helium. Methane gas makes up only one or two percent of the atmosphere but absorbs longer wavelengths of sunlight in the red part of the spectrum, giving the planet its brilliant blue color. Watch the video to see a composite time-lapse assembled from Voyager 2 images of Neptune."

[Shadowmuse Blown]

Makes Earth's hurricanes and tornados speed seem slow. 

NASA Visualization Explorer, September 2013: "Supersonic Wind"

"Neptune, the eighth and farthest planet from the sun, has the strongest winds in the solar system. At high altitudes speeds can exceed 1,100 mph. That is 1.5 times faster than the speed of sound. In 1989, NASA's Voyager 2 spacecraft made the first and only close-up observations of Neptune. Detailed images taken by the spacecraft revealed bright, white clouds and two colossal storms whipping around the planet's atmosphere. Neptune is a gas giant composed primarily of hydrogen and helium. Methane gas makes up only one or two percent of the atmosphere but absorbs longer wavelengths of sunlight in the red part of the spectrum, giving the planet its brilliant blue color. Watch the video to see a composite time-lapse assembled from Voyager 2 images of Neptune."

Cool stuff.  Love the counter rotating winds and the band that looks still between them.  Don’t remember that video, thanks for sharing, Zook!

[TheZookie007]

You're welcome! Neptune and trans-Neptunian planets are hella cool

[solvegas]

 

[TheZookie007]

Because Science: "How to STEAL Elon Musk’s Space Car"
What would it take to steal the only road car currently crossing the cosmos? Kyle outlines a villainous plan that he totally doesn’t approve of.

[Shadowmuse Blown]

The reason for the explosion, the other day, when Booster 7 was testing…
Apparently, there are sometimes minor leaks of whatever gases are used for combustion.  In SpaceX’s Booster and Starship, it’s Methane.  The gases can build up in the surrounding atmosphere and if there’s a spark, everything go boom.  Well, one answer is to have a series of sparks constantly bombard the engine area to ignite the gas before it gets a chance to build up and explode.  Here’s a version used by NASA on the Space Shuttle.

[solvegas]

 

[TheZookie007]

It's a meme, so it is lacking in important detail:

Universe Today, February 2017: "How Long is a Day on Venus?"

Venus is often referred to as “Earth’s Sister” planet, because of the various things they have in common. For example, both planets reside within our Sun’s habitable zone (aka. “Goldilocks Zone“). In addition, Earth and Venus are also terrestrial planets, meaning they are primarily composed of metals and silicate rock that are differentiated between a metallic core and a silicate mantle and crust.

Beyond that, Earth and Venus could not be more different. And two ways in which they are in stark contrast is the time it takes for the Sun to rise, set, and return to the same place in the sky (i.e. one day). In Earth’s case, this process takes a full 24 hours. But in Venus’ case, its slow rotation and orbit mean that a single day lasts as long as 116.75 Earth days.

Sidereal Vs. Solar:

Naturally, some clarification is necessary when addressing the question of how long a day lasts. For starters, one must distinguish between a sidereal day and a solar day. A sidereal day is the time it takes for a planet to complete a single rotation on its axis. On the other hand, a solar day is the time it takes for the Sun to return to the same place in the sky.

On Earth, a sidereal days last 23 hours 56 minutes and 4.1 seconds, whereas a solar day lasts exactly 24 hours. In Venus’ case, it takes a whopping 243.025 days for the planet to rotate once on its axis – which is the longest rotational period of any planet in the Solar System. In addition, it rotates in the opposite the direction in which it orbits around the Sun (which it takes about 224.7 Earth days to complete).

In other words, Venus has a retrograde rotation, which means that if you could view the planet from above its northern polar region, it would be seen to rotate in a clockwise direction on its axis, and in a counter-clockwise direction around the Sun. It also means that if you could stand on the surface of Venus, the Sun would rise in the west and set in the east.

From all this, one might assume that a single day lasts longer than a year on Venus. But again, the distinction between a sidereal and solar days means that this is not true. Combined with its orbital period, the time it takes for the Sun to return to the same point in the sky works out to 116.75 Earth days, which is little more than a half a Venusian (or Cytherian) year.

...Yes, Venus is a planet of extremes. Extreme heat, extreme weather, and extremely long days! In short, there’s a reason why nobody lives there. But who knows? Given the right kind of technology, and perhaps even some dedicated terraforming efforts, people could one day being watching the Sun rising in the west and setting in the east.

[Shadowmuse Blown]

Mars sample return plans:

ESA Earth Return Orbiter launches in 2027

NASA Sample Retriever Lander launches in 2028

Perseverance will deliver its samples to the Mars Ascent vehicle.  Samples return to Earth in 2033

[solvegas]

Perhaps we should change Venus' name to .... HELL! 

[TheZookie007]

Perhaps we should change Venus' name to .... HELL! 

Probably!

Seeker, June 10, 2013: "The Metallic Snow-Capped Mountains of Venus"
Mountains on Venus are capped with snow, just like on Earth. Unlike Earth, Venusian snow is made up of heavy metal-containing minerals.

Some of Earth's most majestic features are its towering snowcapped mountains, reaching high enough that they can sculpt our world's weather systems. But the mountains on Earth are by no means unique, and neither is the snow. Mountains on Venus are also capped with snow. Except that Venusian snow is mostly made from heavy metals.

As you might expect from a planet with such an alien atmosphere, the snow which caps the Venusian mountains is seemingly no less exotic. With the high temperatures on the planet's surface, water ice is impossible (not that there is much water on Venus). It's made from lead sulfide and bismuth sulfide, more commonly known as the minerals galena and bismuthinite.

...After Magellan arrived in the orbit of Earth's twisted sister in the 1990s, it took some more detailed measurements. Everything pointed towards some form of chemical deposition occurring on the higher ground.

As we now understand it, the snow on Venus' surface is probably more similar to frost. On the lower Venusian plains, temperatures reach a searing 480°C (894°F). This is hot enough that reflective pyrite minerals on the planet's surface are vaporized, entering the atmosphere as a kind of metallic mist, leaving only the dark volcanic rocks like basalt in the Venusian lowlands.

At higher altitudes, this mist condenses, forming shiny, metallic frost on the tops of the mountains. And Earth's simmering sibling has plenty of high altitude terrain. Maxwell Montes, the tallest peak on Venus, stands at an altitude of 11 kilometers (6.8 miles) - 3 kilometers (1.8 miles) higher than Mount Everest.

Whether snow genuinely falls on Venus is still unknown, but it's certainly possible. Sulfuric acid rains have been observed plentifully on Venus as virga - rain which evaporates before it hits the ground, just like over the rainforests on Earth.

The heavy metal snows can be observed anywhere on the surface of Venus over about 2.6 kilometers (1.6 miles). It may not be any coincidence that below this altitude Venus's atmosphere is technically no longer a gas.

Over 96 percent of the Venusian atmosphere is carbon dioxide, and our sister planet has nearly 100 times as much atmospheric gas as Earth does. This is what causes the huge crushing pressure at Venus's surface, but that pressure also has a rather strange effect on the gas.

At the pressures and temperatures found near the surface of Venus, carbon dioxide becomes a "supercritical fluid" - an unusual state of matter, partway between a liquid and a gas. Often used on Earth as an industrial solvent, this supercritical carbon dioxide is expected to be found on Venus, coincidentally, at altitudes below around 2 – 3 kilometers (1.2 – 1.8 miles).

While we're a long way from taming Earth's evil twin, meaning that it's unlikely human eyes will see the surface of Venus directly anytime soon, one thing's very likely. Both the lead sulfide and bismuth sulfide which make up Venusian snow are a light greyish color with a shiny, metallic lustre.

Which means the the mountaintops on Venus are probably beautiful, glinting in the sunlight that filters through the dense clouds. Who knows? Maybe in a few hundred years, the Venusian mountaintops might even be a tourist attraction.

[solvegas]

Frankly, I thought it would seem much bigger. 

[TheZookie007]

Frankly, I thought it would seem much bigger. 

yeti dynamics, January 2013: "If the Moon were replaced with some of our planets"

[solvegas]

Frankly, I thought it would seem much bigger. 

yeti dynamics, January 2013: "If the Moon were replaced with some of our planets"

Interesting. I do know that due to the huge mass differences, Earth would become another Moon of Jupiter, Saturn, Neptune and Uranus. Mars could be another Moon for Earth and so could Venus. The tidal waves on Earth would be much larger than they are now. Our planet would be much different than it is now. Frankly, we are lucky about our position in the solar system and the size and mass of Earth.

[TheZookie007]

Yes indeed. Terra is in the "Goldilocks zone": just the right distance away from the Sun, just the right distance away from the Moon, just the right distance away from the major asteroid belts, etc.