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35 votes
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Can the Moon eclipse Venus?

As @Donald.McLean said in comments, the answer is yes, the Moon can and does occult the other planets in the Solar System. When something apparently big (like the Moon) passes in front of something ...
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32 votes
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How was the mass of Venus determined?

How was the mass of Venus measured for the first time? In the mid 19th century, Urbain Le Verrier's predicted of the existence of a then unknown planet beyond the orbit of Uranus. He even predicted ...
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26 votes

Is Venus in some way tidally locked to... Earth?

@BMF's comment links to (Gold & Soter 1969) Icarus 11, (3), November 1969, pp 356-366 Atmospheric tides and the resonant rotation of Venus. Since it is paywalled I'll add a short summary: From ...
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22 votes
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Why did Venus not lose its atmosphere without a magnetic field?

There is an interesting article on the magnetosphere of Venus on the ESA Science and Technology site. You can find the article here and it will probably answer your question. The article states, like ...
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18 votes

How was the mass of Venus determined?

The mass of Venus was determined by weighing the Earth, or more precisely, by determining the ratio of the density of the Earth to the density of Schiehallion, and assuming Schiehallion to be typical ...
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13 votes

Can the Moon eclipse Venus?

Yes, such events are called occultations. The Moon can occult anything within about 5 degrees of the ecliptic. The visibility of any lunar occultation is limited to a path as wide as the Moon is. ...
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13 votes

Is Venus in some way tidally locked to... Earth?

This is a fun little problem that's remarkably close and the math is pretty easy when you use the right periods. Venus' synodic period, relative to Earth, is 583.92 days on average. He uses 584, but ...
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11 votes
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Why do the upper-atmosphere clouds of Venus appear to have that V shape?

This is supplementary to antispinward's excellent answer and provides additional sources and a visualization from the JAXA spacecraft Atasuki. It has been shamelessly borrowed from Would it be ...
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10 votes

Why did Venus not lose its atmosphere without a magnetic field?

There are other ways to lose atmosphere. For example Jean's Escape. If average velocity of a gas molecule exceeds escape velocity, the planet will lose atmosphere. Venus' atmopshere is mostly $CO_2$ ...
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10 votes

Are there ever any simultaneous transits of both Mercury and Venus as seen from the Earth?

As others have calculated, there are no predicted double transits. Since Venus transits for about 12 hours each hundred years (roughly), Venus is in transit for about 1/100000 of the time. Thus ...
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10 votes

Is the Earth going to evolve towards Mars' fate or Venus' fate?

Either or neither. It's impossible to tell from the present. If runaway climate change occurs, then yes, the conditions on Venus could be a potential analogue for the kind of environment on Earth due ...
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10 votes
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Is the Earth going to evolve towards Mars' fate or Venus' fate?

If you are asking about short-term effects related to human's effect on the climate, the answer is (obviously) unclear. But in the very long term, Earth is likely to evolve to a more Venus-like state. ...
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10 votes

How can we see Venus at night?

Before we begin: how far a planet is seen from the Sun is called elongation, and it's measured in degrees. 0° elongation means it's right on top of the Sun (or behind); 180° elongation means it's ...
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10 votes
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Why has the orbit of Venus such a low eccentricity?

It has a low eccentricity, but there may not be a particular reason. Image by Kheider on wikipeda using Gravity Simulator by Trevor Dunn In a simulation of the solar system, both Earth and Venus had ...
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10 votes
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Is extra-planetary phosphine actually a new discovery?

You're correct; extraterrestrial phosphine is not actually a new discovery. As you said, we've known for decades (see e.g. Ridgway et al. 1976) that phosphine can and does exist in some gas giant ...
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9 votes
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Can we find rocks from Venus or Mercury on Earth?

You can think of it in terms of Hohmann transfer orbits, which define the minimum $\Delta v$ that needs to be applied to bring something from one orbital radius to another orbital radius when orbiting ...
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9 votes
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Can lunar occultation of Venus occur during solar eclipse?

Yes, but such an event would be very rare. Venusian transits last only about 7 hours, and there are only two in 113 years, So Venus is in transit for about 0.0015% of the time. So as a back-of-the-...
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  • 90.4k
9 votes
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Has Hubble photographed Venus in near IR? If so how does it compare to the new and exciting Parker Solar Probe image?

This web page -- "Here is why the Hubble Space Telescope only looked a few times at Venus (and why it looked at the Moon instead)" -- seems like a pretty good answer to your main question (...
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9 votes
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What would happen if Venus was hit by a Chicxulub-like meteor?

Question: Would the dense atmosphere and high surface pressure and temperature lead to a different result compared to what happened here on Earth? Short Answer: No. There will not be any significant ...
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8 votes

Could Venus or Mercury have a moon that we haven't detected?

It's unlikely that either Mercury or Venus could have moons to begin with. Both of these planets are pretty close to the Sun — and in general, this prevents moons from finding stable orbits. If a ...
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8 votes
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How (the heck) was this photo of Venus at inferior conjunction (between us and the Sun) taken?

I think you'll have to live with an incomplete answer. It appears this was taken by an amateur astronomer using a simple 4.5 inch telescope. You can find, on the ESO website, a collection of many ...
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8 votes
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Why Venus evolved so differently from Earth?

Venus orbits the Sun at 0.723332 AU. As solar radiation follows an inverse square law, the intensity of the Sun at the top of Venus's atmosphere is almost twice that for the Earth ($\frac1{0.723332}^...
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8 votes
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How can it be known that Venus does not have plate tectonics?

There's much less data available from Venus. Some data exists. As mentioned in HDE 226868's answer, maps of Venus's surface exist. Like Earth's atmosphere, Venus's atmosphere is transparent to some ...
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8 votes

Phosphine on Venus?

Essentially what they did was assume that normally when observing with their telescope the spectral absorptions they see are due to the Earth's atmosphere. Which is a pretty good assumption. They then ...
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  • 498
7 votes

Could an impact have resurfaced Venus 300 million years ago?

Would an impact event leave visible traces like impact basins, or could the entire surface melt and reform as it is today, as I suppose Earth did when the Moon formed? Could Venus have been a very ...
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7 votes
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Is it possible that Mercury was originally the moon of Venus after a giant impact?

This was originally going to be a comment, but it ran too long, so I'm making it an answer. Some models argue that the scenario of a satellite of Venus escaping like this is unlikely. Alemi & ...
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