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Comments · 8
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So what they did ...
... was actually find a way to get more hours (or minutes) into a day? Don't tell my boss or he'll have us working Venus days.
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Smallest visible object on the moon from Earth...Umm... the eye doesn't work by seeing a percent of area - the eye has a working resolution, like a digital camera. The question is, what's the resolution of the human eye, and what's the smallest thing that can be resolved by that resolution at the distance of the moon?
This Article indicates that an average resolution is either 4 arc-minutes or 6 arc-seconds. The 6 arc-seconds makes more sense than 4 arc-minutes (4 arc-minutes is a whopping 1.2 mm at a distance of 1 m (I don't know about you but I can see better than that!), where 6 arc-seconds is 0.03 mm (about
"Using math since 1986 to sound like I know what I'm saying"
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Re:Climate change?Venus is virtually the same size as Earth and, on average, is our nearest neighbour. Today, its atmospheric temperatures are hot enough to melt lead and concentrated sulfuric acid continuously drizzles down from thick sulphurous clouds that completely block out the Sun.
Another poster: And you don't think the fact that Venus is MUCH closer to the Sun has anything to do with its hotter temperatures? If the distance from the Sun to the Earth were to change by only a few percent either way we'd become a desert planet or we'd be an ice ball, and the activities of Man would have nothing to do with the outcome.
Not as much effect as you think. As you can see here, Venus is 30% closer to the Sun than the Earth is. A simple application of the blackbody equation to calculate the surface temperature of a planet shows that one would expect Venus to have a surface temperature of about 22 deg C. In fact it has a temperature of 464 deg C. The difference is entirely due to the greenhouse effect. So yes, the greenhouse effect is very real and can have tremendous impact on the surface temperature of a planet. I should also point out that without the greenhouse effect, the Earth itself would be rather cold: about -22 deg C. Given that the presence of a tiny amount of CO2 and water vapor is enough to change the mean surface temperature of the Earth by 40 deg C, it is not unreasonable to think that an increase in the CO2 concentration by 50-100% might raise surface temperatures.
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Re:Joint mission?
Seesh, did you read the proper answer?
A) Mercury does rotate. However, your "proper answer" got it wrong; while Mercury rotates on its axis every 58.6 days, it's moved a long way around the sun in that same time. As a result, it's day (period between one sunrise and the next) takes longer than its rotation period. In fact, it takes about 3 rotations to get one 'day'. Also, because of the elliptical orbit and long rotation period, you can get a funky double-sunset effect, when the sun sets, then rises again in reverse before setting again.
B) Mercury does so have an atmosphere. The atmosphere is, on average, about 440K; quite hot enough. The night side is cold, not because there is no atmosphere, but because the atmosphere is so thin it radiates the heat away into space very fast. Mercury actually has a very turbulent convenction system, especially around the terminator line. -
Re:Joint mission?
Firstly, of course the moon rotates as well. It just rotates at the same angular velocity at which it orbits Earth, so we always see the same face. This is caused by a process called tidal lock.
Mercury is in tidal lock with the sun. But because its trajectory is elliptical, it's not a 1:1 lock, but a 3:2 lock: there are 3 Mercury days in 2 Mercury years.
A Mercury day is 58.6 Earth days, a Mercury year is 88 Earth days, according to this fact sheet. 58.6 days should be enough for most missions.
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Re:kinda knocks the pants off 1km
It is much farther than that from the Earth to the moon. The average distance from the Earth to the moon is 384,467 kilometers
Earth to Moon -
Just to put things in perspectiveIf you can manage to get the close-up of the sunspots, concider the big one roughly in the middle. If the tickmarks are correct, it is roughly 12,000 x 16,000 km.
The diameter of the earth is pretty darn close to that.
Moral to the story: sunspots are really big.
No, I mean it.
Big.
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and in other newsMiddle and high school science websites Middle/high school science websites List of the educational middle/high school science websites I have developed.
Home
Just over 50 middle and high school science WebQuests are spread throughout these educational websites.Contains the historical timeline of measuring the speed of light. There are 3 quizzes with 30 questions about the speed of light.
There are 50 quiz questions about light, lenses, the wave theory of light, reflection and refraction for grade 4 to 7 students.
1001 Periodic Table Quiz Questions
Contains over 1300 science and chemistry questions. These questions are arranged per age group and science topic.
Explains: Why is the sky blue?, Why is the ocean blue?, Why are sunsets red?, Why are clouds white? and Why is Mars red?
There are 5 quizzes with 50 questions in total to test your understanding of these explanations.
Contains over 200 pictures of the planets in our solar system (except Mars, Jupiter, Saturn and Pluto). After each web page there are a few review questions about the pictures on that page.
There are also 15 picture quizzes with 75 questions - each question comes with a small picture.
Contains over 30 pictures of the planet Mars. After each web page there are a few review questions about the pictures on that page.
There are also 3 quizzes with 25 questions about the planet Mars - only 10 questions come with a small picture.
Contains over 60 pictures of the planet Jupiter. After each web page there are a few review questions about the pictures on that page.
There are also 5 quizzes with 40 questions about the planet Jupiter - only 15 questions come with a small picture.
Contains 25 pictures of the planet Saturn. After each web page there are a few review questions about the pictures on that page.
There are also 4 quizzes with 30 questions about the planet Saturn - only 10 questions come with a small picture.
Contains 3 pictures of the planet Pluto. After each web page there are a few review questions about the pictures on that page.
There is a quiz with 10 questions about the planet Pluto - it does not have any pictures.
A website dedicated to Galileo Galilei, his inventions and discoveries.
There is a set of 10 quizzes about Galileo Galilei, his inventions, discoveries and The Starry Messenger (Sidereus Nuncius).
There are 10 other quizzes about several other famous astronomers.
Contains reference lists of capital cities per continent. There are 54 quizzes with over 1080 capital city questions in total.
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