Wikipedia:Reference desk/Archives/Science/2009 July 16
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July 16
The Cancer Genome Atlas
Did they name it that just so the abbreviation would be composed of letters that represent the bases of DNA? or is it just a coinkydink? —Preceding unsigned comment added by 129.64.55.234 (talk) 13:35, 16 July 2009 (UTC)
- I like your explanation. You could be right, it's certainly been noted before. AlmostReadytoFly (talk) 13:43, 16 July 2009 (UTC)
- While I don't see a specific "what's the name mean?" on their site, "TCGA" strikes me as too topical to be a coincidence. I would guess that there's a degree of backronyming at work. — Lomn 13:45, 16 July 2009 (UTC)
- I mean, "Atlas" is an interesting word to use. They could have easily named it The Cancer Genome Project. Maybe they got bored of the word "Project" 129.64.55.234 (talk) 14:02, 16 July 2009 (UTC)
- A "gene atlas" (hmm...no article?) is a common term for this kind of thing. DMacks (talk) 14:58, 16 July 2009 (UTC)
- I mean, "Atlas" is an interesting word to use. They could have easily named it The Cancer Genome Project. Maybe they got bored of the word "Project" 129.64.55.234 (talk) 14:02, 16 July 2009 (UTC)
- Charles Stross once used the phrase the Genetic Algorithm That Ate Calcutta. I asked whether the acronym was intentional (this was when Gattaca was fresher in memory); he had not noticed it. —Tamfang (talk) 00:20, 21 July 2009 (UTC)
Plants listed by oxygen production/toxin removal
I recently watched a Ted Lecture [1] by Kamal Meattle in which he outlines how to create an oxygen neutral building by using 3 varieties of plants that:
-Remove Toxins from the air (Money Plants)
-Provide oxygen during the day (Areca Palms)
-Provide oxygen during the night (Mother-in-law's Tongues)
The specific plants he names might not work for me because of sunlight/space/decor/availablity reasons in my home. Where can I find a list of common household plants in order of oxygen production? Or by Toxin removing ability (I know that can be ambiguous)? How much do these attributes vary from plant to plant (Does it even matter what plants I get?)
I had been under the assumption that oxygen production was based off sun facing surface area of the plant and how much of that sunlight it processes, since the oxygen is a byproduct of photosynthesis, but then it seem strange that plants would produce any oxygen at night, like the Mother-in-law's Tongue, so I am now comptelely lost as to what determines the above attributes.
Any other advice to what plants I can use to improve air quality in my home will be greatly appreciated. Anythingapplied (talk) 20:09, 16 July 2009 (UTC)
- I suspect that guy is a crank and should be ignored. His biography (linked to from that page) doesn't suggest any scientific training and his technique makes no sense. As you say, oxygen is produced by photosynthesis, it can't be produced at night (unless you leave your office lights on over night, I guess). As for removing toxins, as far as I am aware the only "toxin" plants remove from the air is carbon dioxide, also by photosynthesis, and you don't need to worry about that as long as you have reasonable ventilation. --Tango (talk) 21:04, 16 July 2009 (UTC)
- People who give talks at TED (conference) are not usually cranks - and should almost certainly not be ignored. As it happens, it looks like all of his claims have at least some truth to them. Our article on Sansevieria trifasciata (Mother-in-law's tongue) says (with a pretty decent reference) that they remove "certain" toxins from the air and can flourish in low light levels. That may well mean that they can continue to do photosynthesis under artificial lighting - which may be why Meattle thinks they emit oxygen at night...but in complete darkness, that seems impossible. There are three completely different plants called Money plants - but I suspect he means Epipremnum aureum which (according to our article) is good at sucking up all sorts of pollutants. Areca is a family of about 50 different kinds of palm tree - we only have articles on a few of them - and most of those are slim on details - but Areca catechu is claimed to be a popular indoor plant so that's probably what this guy is talking about...however, pretty much all green plants will produce oxygen during the day...so that's an easy choice. SteveBaker (talk) 23:34, 16 July 2009 (UTC)
- Your "decent reference" is a broken link... Given that any half decent ventilation will get plenty of oxygen into a building, I'm still voting crank. Even TED can get fooled. --Tango (talk) 00:19, 17 July 2009 (UTC)
- You are entirely wrong. The reference is to a scientific paper - the link to a copy of the paper on the NASA site is broken - but simply typing the title into Google and accepting the first hit gives you the paper. Did you watch the TED lecture? Ventilating a building is not "oxygen neutral" and it wastes heating/airconditioning energy. The goal of making a building oxygen-neutral has value. SteveBaker (talk) 02:49, 17 July 2009 (UTC)
- Your "decent reference" is a broken link... Given that any half decent ventilation will get plenty of oxygen into a building, I'm still voting crank. Even TED can get fooled. --Tango (talk) 00:19, 17 July 2009 (UTC)
- People who give talks at TED (conference) are not usually cranks - and should almost certainly not be ignored. As it happens, it looks like all of his claims have at least some truth to them. Our article on Sansevieria trifasciata (Mother-in-law's tongue) says (with a pretty decent reference) that they remove "certain" toxins from the air and can flourish in low light levels. That may well mean that they can continue to do photosynthesis under artificial lighting - which may be why Meattle thinks they emit oxygen at night...but in complete darkness, that seems impossible. There are three completely different plants called Money plants - but I suspect he means Epipremnum aureum which (according to our article) is good at sucking up all sorts of pollutants. Areca is a family of about 50 different kinds of palm tree - we only have articles on a few of them - and most of those are slim on details - but Areca catechu is claimed to be a popular indoor plant so that's probably what this guy is talking about...however, pretty much all green plants will produce oxygen during the day...so that's an easy choice. SteveBaker (talk) 23:34, 16 July 2009 (UTC)
- Nasa has a couple of pages, this one works [2] and discusses TCE, Benzene and Formaldehyde reduced in a chamber of plants. They don't single out Sansevieria. A place called Stennis Space Center seems to have studied plants for cleaning air and waste water. BTW: Pollutant would probably be a better term than Toxin here. Maybe that's what is causing the confusion. 71.236.26.74 (talk) 00:36, 17 July 2009 (UTC)
- Actually, that's a good ref. The reason why words like "toxin" and "polutant" and things like that are often dismissed is because of their non-specific nature which makes claims which use those terms largely unfalsifiable. If you want to believe a claim, find one that lists specific compounds which are filtered by the plants. Which it looks like you have done. But in general, that's why words like "toxin" are clear bullshit markers. Nothing filters "toxins". Things may filter or remove specific compounds or classes of compounds, but if so then those compounds can be identified, and any serious scientificly-based report on such methods WILL list those compounds. If it doesn't, it's bullshit. --Jayron32.talk.say no to drama 01:48, 17 July 2009 (UTC)
- Nasa has a couple of pages, this one works [2] and discusses TCE, Benzene and Formaldehyde reduced in a chamber of plants. They don't single out Sansevieria. A place called Stennis Space Center seems to have studied plants for cleaning air and waste water. BTW: Pollutant would probably be a better term than Toxin here. Maybe that's what is causing the confusion. 71.236.26.74 (talk) 00:36, 17 July 2009 (UTC)
- If anyone could find an explanation of the mechanism somewhere could you post a link? I've found a couple of studies for quantative analyses, but nothing explaining the mechanism so far. 71.236.26.74 (talk) 02:43, 17 July 2009 (UTC)
- Is someone here planning to build a spaceship / nuclear submarine? Cause these are the only two applications I know of where being "oxygen-neutral" would matter at all.76.21.37.87 (talk) 04:42, 17 July 2009 (UTC)
Thanks guys for all your help. I'm not sure I know much about which ones produce more oxygen than others, but the NASA link was very helpful for toxin. Apparently the NASA stuff was already on Wikipedia and I wasn't looking hard enough: List_of_air-filtering_soil_and_plants. While you do have a point 76.21, by putting enough plants in my house to cancel out my oxygen use in addition to it already be ventilated I am actually creating an oxygen rich environment, so perhaps I shouldn't be expressing my desire as specifically archiving an "oxygen-neutral" environment. Plus, I think ANY submarine would probably want to be oxygen neutral, not just nuclear ones. The scientific names were actually in the video now that I look back at it:
Chrysalidocarpus lutescens, Epipremnum aureum, and Sansevieria trifasciata
Which are actually all from the NASA list, credited for removing xylene and toluene for the first one in the above list and formaldehyde for the second two.
Out of curiosity, any idea how many plants I would need to provide for 1 person's oxygen needs? Anythingapplied (talk) 05:16, 17 July 2009 (UTC)
It may be worth reading the comments [3] here. In terms of plants that release oxygen during the night, it appears he's referring to plants that have Crassulacean Acid Metabolism. While my first thoughts on this were similar to Tango's it may also be worth remembering he's from India where air pollution is a lot worse then many Western countries and on his page it says "including an air-cleaning system that involves massive banks of plants instead of massive banks of HVAC equipment" and "making a green office accessible to more businesses in New Delhi and serving as an example of low-cost, low-energy office life" in other words, he acknowledges that you can do the same thing with HVAC equipment, he primarily wants to reduce energy expenditure. [4] may also be worth a read. Nil Einne (talk) 18:34, 19 July 2009 (UTC)
"I think ANY submarine would probably want to be oxygen neutral, not just nuclear ones." -- True, but in the case of a diesel sub, that would be impossible (the diesel engine uses A LOT of air in a short time), and not really critical in any case cause they'd still have to surface every 24-48 hours to recharge the batteries. FWiW 76.21.37.87 (talk) 00:20, 20 July 2009 (UTC)
Parasympatholytica
Where can I find a list of parasympatholytic drugs? (Need not be drugs prescribed by medics, just chemicals that act as parasympatholytica no matter of strength or side effects.)
Second question: if the parasympathic nervous system was malfunctioning (to any degree) what would be the effects on the body?
No, I'm not trying to poison someone, there would be easier ways and besides, wikipedians are not to give legal advice anyway. 95.112.156.108 (talk) 20:41, 16 July 2009 (UTC)
- Did you see our article on Parasympatholytic drugs? There are some links and references on there that may be able to help you out. Livewireo (talk) 20:55, 16 July 2009 (UTC)
- The little there is to see, yes. That's why I'm posting here. 95.112.156.108 (talk) 21:06, 16 July 2009 (UTC)
- Acetylcholine#Antimuscarinic Agents lists a few, but I'm sure there are a lot more. Looie496 (talk) 03:59, 17 July 2009 (UTC)
- The little there is to see, yes. That's why I'm posting here. 95.112.156.108 (talk) 21:06, 16 July 2009 (UTC)
- These sound like homework questions. Anyway, a quick look at anticholinergics leads to antimuscarinics and antinicotinics - which both list many drugs. For the second question, well the effects of anticholinergics basically is what would happen if the PNS wasn't working.. --Mark PEA (talk) 10:29, 17 July 2009 (UTC)
Atmosphere and Gravity
How much gravity on another planet would be necessary to have an atmosphere where people could thrive (assume other factors such as average temp, composition, are similar to earth although I'm interested in what other factors would have an influence). Also, how much gravity could people comfortably live with? TheFutureAwaits (talk) 20:57, 16 July 2009 (UTC)
- We really don't know what gravity humans can live in. Pretty much no research has been done on gravity greater than Earth's, and pretty much the only research on lower gravity is zero gravity and humans can't survive in that for long without taking some precautions (lots of exercise, mainly, I think). I'm not sure about gravity and atmospheres. I know temperature is a big factor - it is easier to "hold on to" cold air than hot air. That's why Titan has a thick atmosphere (about 50% greater pressure than Earth) despite being much smaller than Earth. The composition also matters - humans can survive (at least temporarily) with about a fifth of Earth's atmospheric pressure if it is pure oxygen or with pressure of about 10 times Earth's if you replace most of the air with something inert like Helium (see Heliox). I think composition also affects pressure and density - Venus has about the same gravity as Earth and is really hot, so you would expect it to have a thinner atmosphere, but it is actually about 100 times thicker. I'm guessing that's because it is mainly CO2 which is a little under twice as heavy as air (per mole). --Tango (talk) 21:28, 16 July 2009 (UTC)
- (after ec without rereading the new contribution) Sorry that I don't have sources to cite but from what I have heard, the size of our earth is on the verge of being too light and loosing hydrogen (THE key element for live as we know it) and being too heavy and attracting excessive hydrogen and finally becoming a gas giant. I'm hoping for answers that are less based on private memory and hearsay. 95.112.156.108 (talk) 21:30, 16 July 2009 (UTC)
- We have lost all our (free) hydrogen. The only hydrogen that remains is that in compounds with heavier elements (particularly oxygen in water). Any hydrogen that gets released into the atmosphere escapes sooner or later. Free hydrogen isn't important for life. --Tango (talk) 21:36, 16 July 2009 (UTC)
- As far as I understand, on a geological time scale any hydrogen, temporarily bound or not, will escape a lighter planet with a temperature comparable to earth. Look at venus, look at mars. 95.112.156.108 (talk) 21:50, 16 July 2009 (UTC)
- The hydrogen on Earth is pretty permanently bound. It undergoes various chemical reactions but that just changes what it is bound to. There aren't many naturally occurring reactions that produce free hydrogen. I've certainly never heard of any risk of running out of water before the sun heats up and boils it all off. --Tango (talk) 23:03, 16 July 2009 (UTC)
- Besides, Venus and Mars don't have a "temperature comparable to Earth"... 76.21.37.87 (talk) 04:47, 17 July 2009 (UTC)
- The temperature on Mars CAN get up to Earthlike values - they've recorded 70 degF on a few occasions. However, mostly it's way colder - and Venus is crazily hotter. SteveBaker (talk) 14:12, 17 July 2009 (UTC)
- Besides, Venus and Mars don't have a "temperature comparable to Earth"... 76.21.37.87 (talk) 04:47, 17 July 2009 (UTC)
- The hydrogen on Earth is pretty permanently bound. It undergoes various chemical reactions but that just changes what it is bound to. There aren't many naturally occurring reactions that produce free hydrogen. I've certainly never heard of any risk of running out of water before the sun heats up and boils it all off. --Tango (talk) 23:03, 16 July 2009 (UTC)
- As far as I understand, on a geological time scale any hydrogen, temporarily bound or not, will escape a lighter planet with a temperature comparable to earth. Look at venus, look at mars. 95.112.156.108 (talk) 21:50, 16 July 2009 (UTC)
- We have lost all our (free) hydrogen. The only hydrogen that remains is that in compounds with heavier elements (particularly oxygen in water). Any hydrogen that gets released into the atmosphere escapes sooner or later. Free hydrogen isn't important for life. --Tango (talk) 21:36, 16 July 2009 (UTC)
- The question is how much gravity is necessary for a planet to have an atmosphere where humans could thrive. The answer is just enough gravity to hold water vapor for a large amount of time. A Mars sized planet is likely close to the right answer. Dauto (talk) 05:51, 17 July 2009 (UTC)
- Then how come there ain't no water on Mars anymore? 76.21.37.87 (talk) 06:29, 17 July 2009 (UTC)
- No one knows at the moment (No one even knows how much water is gone and how much is just "hidden", e.g. subsurface). There are some hypothesis were the water went and why and when, but the history of mars is not really known to any degree of certainty. And btw, also for venus we do not understand at the moment what "planetary development" has led to its present state. So science cannot answer these questions at present, because we do not have any additional samples beside earth for a habitable planet. --TheMaster17 (talk) 09:57, 17 July 2009 (UTC)
- We know from studies of craters and erosion that water has been on the Martian surface 'recently in geological terms'. The gravitational force of Mars hasn't changed measurably for a billion years - so how come the water would have stayed around for all that time if a lack of gravity was the cause of it 'going away'. That means that it wasn't a lack of gravity that caused the water to "go away" - or all of the evidence of flowing water would long ago have been eradicated by meteor impact and wind erosion. SteveBaker (talk) 14:12, 17 July 2009 (UTC)
- No one knows at the moment (No one even knows how much water is gone and how much is just "hidden", e.g. subsurface). There are some hypothesis were the water went and why and when, but the history of mars is not really known to any degree of certainty. And btw, also for venus we do not understand at the moment what "planetary development" has led to its present state. So science cannot answer these questions at present, because we do not have any additional samples beside earth for a habitable planet. --TheMaster17 (talk) 09:57, 17 July 2009 (UTC)
- Then how come there ain't no water on Mars anymore? 76.21.37.87 (talk) 06:29, 17 July 2009 (UTC)
- There is water on Mars. May be your question should have been 'how come there ain't no ocean on Mars anymore' The answer is related to surface temperature and pressure. The question was about surface gravity. Some of Mars water has likely been lost due to low gravity over a period of hundreds of millions of years. That's more than enough time for humans to thrive which was the citerion stablished by the question. Dauto (talk) 16:20, 17 July 2009 (UTC)
- Wouldn't the low pressure be bad for people too? 76.21.37.87 (talk) 01:44, 18 July 2009 (UTC)
- Yes, if the atmospheric pressure is too low it can be bad for people. But that's a separate question because surface pressure is not determined by surface gravity alone. You also must take into consideration the atmospheric total mass. Dauto (talk) 04:03, 18 July 2009 (UTC)
- So would it be possible to have a decent-sized atmosphere on a Mars-sized planet? 76.21.37.87 (talk) 04:41, 18 July 2009 (UTC)
- Yes. Dauto (talk) 02:05, 19 July 2009 (UTC)
- OK then, I rest my case. 76.21.37.87 (talk) 04:10, 19 July 2009 (UTC)
- Yes. Dauto (talk) 02:05, 19 July 2009 (UTC)
- So would it be possible to have a decent-sized atmosphere on a Mars-sized planet? 76.21.37.87 (talk) 04:41, 18 July 2009 (UTC)
- Yes, if the atmospheric pressure is too low it can be bad for people. But that's a separate question because surface pressure is not determined by surface gravity alone. You also must take into consideration the atmospheric total mass. Dauto (talk) 04:03, 18 July 2009 (UTC)
- Wouldn't the low pressure be bad for people too? 76.21.37.87 (talk) 01:44, 18 July 2009 (UTC)
- There is water on Mars. May be your question should have been 'how come there ain't no ocean on Mars anymore' The answer is related to surface temperature and pressure. The question was about surface gravity. Some of Mars water has likely been lost due to low gravity over a period of hundreds of millions of years. That's more than enough time for humans to thrive which was the citerion stablished by the question. Dauto (talk) 16:20, 17 July 2009 (UTC)
Pluto's diameter and why gas giant's moon number keep growing
Is Pluto 1400 miles or 1500 miles (0.18 or 0.19 x Earth). [5] say Pluto is x0.18 Earth, NASA say is 0.19 x Earth. Which one is accurate. I thought Microsoft Windows, any kids website is not a valid source. Is Saturn up to 61 moons right now? Anyways, how we know gas giant's moon keep growing. First when last Voyager 2 went to Uranus and Neptune, they had 15 and 8 moons, then in 2000 Uranus had 22 moons then finally Uranus have 27 moons, and finally Neptune have 13 moons. When last Voyagers visit Jupiter, it had 16 moons, then few in 2000 Jupiter's moon jump to 20s, then 30s in 2003 Jupiter's moon skyrocket to 61 moons then finally it's 63. Saturn's moon start with 18 moons, then 30s, then 56 in 2006, then finally 61. Did they use HST or what tools to find new and new moons. Is this possible numbers of Uranus and neptune will continue skyrocketing? Could somday Uranus have up to 40 moons and Neptune have over 19 moons? adn jupter and Saturn over 100 moons?--69.228.145.50 (talk) 21:00, 16 July 2009 (UTC)
- I don't think we know the diameter of Pluto very accurately. It depends on its albedo - how bright its surface is. If it is quite dark then it must be quite big in order to reflect the amount of sunlight it does, if it is brighter then it must be quite small. As for the moons, we just keep discovering more (they've all been there the whole time, we just hadn't noticed them). A lot of them are very small and there is no reason to believe we've found them all or will do any time soon. You also have to remember that there isn't really any difference between the tiny dust particles in the rings and the smallest moons (other than size, obviously), so you could argue that we already know of millions of moons around each gas planet - it depends where you draw the line. --Tango (talk) 21:34, 16 July 2009 (UTC)
- O, this explains why scientific plotting always fails. Even surface temperatures can't be pin right. By the way nothing is space is exactly pin right, always universally error bars. People can literally say Venus is >1000 F, this is why we have book say Venus is 600 C. I would say Jupiter and Saturn have 100s of moons if 100% is found, for Uranus and Neptune, this is impossible to be over 50 moons if 100% of them if found.--69.228.145.50 (talk) 22:18, 16 July 2009 (UTC)
- There are always error bars, you are right, but for some things they are pretty small. We've sent probes for Venus, so we have a pretty good idea of its temperature. The error bars on our measurements will be much smaller than the variation in the temperature. --Tango (talk) 23:05, 16 July 2009 (UTC)
Glycerin free personal lubricants
I notice many new "personal" (sexual) lubricants proclaim they are glycerin and paraben free. What about those ingredients are bad during sex? --70.167.58.6 (talk) 21:51, 16 July 2009 (UTC)
- Substances that dissolve your condom counteract the reasons why you were using it. It has nothing to do with sex itself. 95.112.156.108 (talk) 22:05, 16 July 2009 (UTC)
- True, but not applicable to the substances the OP listed. Only water-based lubricants (i.e. not Vaseline) should be used with condoms, for the reason you state. Glycerine is a common allergen, and parabens are both allergens and potential carcinogens; these are the reasons for wanting lubricants without those ingredients. jeffjon (talk) 12:50, 17 July 2009 (UTC)
I wonder the valid source of this site. Most showing I see is African plate moving north, the slide show African plate moving east only, eventually it suppose to collide with European plate closing Arabian and Black Sea. Isn't North and South Amercan plates moving west only no north. I don't expect over 15 lattitude north shifting in about another 100 million years. I expect at least the Northern Africa would be up to Artic Circle in 100 million years. Australia is just quickly moving north, and will collide and form a huge nountain in East Asia.--69.228.145.50 (talk) 22:23, 16 July 2009 (UTC)
healthy diet and muscle spasms
What vitamins or minerals are supposed to be linked to muscle spasms when in deficiency? 76.123.145.220 (talk) 23:39, 16 July 2009 (UTC)
- Potassium. --Tango (talk) 23:44, 16 July 2009 (UTC)
- And Calcium. Please see Hypokalemia and Hypocalcaemia, respectively. --Dr Dima (talk) 01:10, 17 July 2009 (UTC)
- And magnesium. It should be noted that fasciculation can be caused by many things other than vitamin/mineral deficiency. --Mark PEA (talk) 10:20, 17 July 2009 (UTC)
Man on Moon
Have anybody else besides those 3 people in July 1969 Buzz what's his name, Neil Armstrong and anyther guy all 79 right now have been on Moon. Have anybody been on dayside of Moon, or only night side. Do we have 1000s of people been on Moon or it's only those 3 peoples in 1969. Space travel is not a vacation spot. It is not just few days to get to Moon, I expect two weeks from Earth to Moon. Plus to survive in space, people have to bring gravity to hold things together, and lots of foods and fuels and liquids, and place to sleep and shower on.--69.228.145.50 (talk) 23:49, 16 July 2009 (UTC)
- Twelve people have walked on the moon. Only two did so in July 1969 (the other guy stayed in orbit). We do not yet have a way of taking portable gravity into space. Algebraist 23:52, 16 July 2009 (UTC)
- "The other guy" is Michael Collins. The poor guy, nobody ever remembers his name... --Tango (talk) 00:12, 17 July 2009 (UTC)
- Nobody except for you and me, that is. 76.21.37.87 (talk) 04:49, 17 July 2009 (UTC)
- And Cuddlyable3, apparently... 76.21.37.87 (talk) 04:38, 19 July 2009 (UTC)
- As a matter of interest, have Aldrin and Collins ever expressed any resentment towards Neil Armstrong? I know that there's been plenty of comedy sketches about 'nth men on the moon' being bitter about their lack of historical recognition over the years... --Kurt Shaped Box (talk) 02:16, 19 July 2009 (UTC)
- "The other guy" is Michael Collins. The poor guy, nobody ever remembers his name... --Tango (talk) 00:12, 17 July 2009 (UTC)
- If it’s seeming like that tiny Lunar Module is too small to hold everything needed for a trip to the moon, you are right. Although the most exciting photos and videos of the moon landing only show the lunar module, the lunar module was only one piece of the Apollo spacecraft, which did hold enough stuff. Not much fuel is needed to get back from the moon, since it’s relatively easy to escape from the moon’s gravity, due to there being a lot less gravity on the moon than on the earth. Escaping the earth’s gravity, however, does require a lot more fuel, which is why the Apollo spacecraft started out on the tip of a huge launch vehicle.
- A bed to sleep in and the ability to take showers are luxuries of modern living, that aren’t really requirements when you’re on a monumental adventure.
- Gravity isn’t required to hold things together. The main thing that holds thing together are chemical bonds.
- I could go into the details of how the energy content of the fuel used on the Apollo missions was enough to get the Apollo spacecraft traveling fast enough so that it could get to the moon in only a few days. However, no offense if I’m wrong, but I’m guessing that you’re fairly young, and haven’t yet taken the elementary physics classes that would be required for you to understand the explanation. However, the idea of it being impossible to reach a speed fast enough to get to the moon in three days isn’t even something that we have listed as being one of the objections of the moon landing hoax conspiracy theorists. Red Act (talk) 01:24, 17 July 2009 (UTC)
As to the question about which side of the Moon, all of the Apollo missions landed on the near side of the Moon (the side facing the Earth), so they could communicate with the Earth by radio; and they all landed when it was daytime at the landing site, and left when it was still daytime, so they didn't have to deal with the day/night temperature change and so they had full sunlight to work by. (Remember, daytime on the moon lasts for almost two weeks. Apollo 17 stayed longest on the lunar surface, about 75 hours.) --Anonymous, 04:46 UTC, July 17, 2009.
- LOL. Two gravity to go, hold the ketchup- KoolerStill (talk) 13:20, 17 July 2009 (UTC)
- ec. the sides of moon they been on is nighttime with most photos we have with no suns, yes the image always fails when trying to make things look true when try to pin a green dot to show you what it will look like when you actually on moon. Different gravity and lighting conditions on moon, beleive it or not; the images we take is 99.99% hopelessly wrong, then our orange, blue, green light go haywire. Dummies think it is so easy to say Moon is gray, that's just balonies! We had this discussion many times in past, that's over!--69.228.145.50 (talk) 21:21, 17 July 2009 (UTC)
- They landed during lunar morning for idea temperature, and on the side facing earth for best radio contact. We will soon be celebrating the 40th anniversary on earth, but I would like to point out that the moon's phase will not be correct (because Earth's revolution around the sun is not closely linked to Moon's revolution and orientation around Earth). Flimsy human calendars fail to capture useful astronomical information! LCROSS arrived around lunar morning a few weeks ago; it's probably a better "anniversary" than July 16 or July 20, from the point of view of the Moon. Nimur (talk) 14:30, 17 July 2009 (UTC)
At the risk of stating the obvious : The Moon has its own gravity. It does not have as much gravity as Earth, but it still has a useful amount. The astronauts don't need to bring any with them. This is a good thing because there is no known way to make gravity "portable". (When NASA needs to "hold stuff down", they usually glue Velcro to everything Velcro.) APL (talk) 14:52, 17 July 2009 (UTC)
- Gravity is portable, you just need a really huge engine. If you built a spaceship of the same dimensions and weight as earth, and you could move it around, then you would in effect have portable gravity. You would have to ask if the endeavor would be worth the resources though. Googlemeister (talk) 18:30, 17 July 2009 (UTC)
The OP should remember the name Buzz Aldrin. He is not to be confused with Buzz what's his name the inventor of the rubber suction cups used to hold things together in space. Cuddlyable3 (talk) 01:45, 19 July 2009 (UTC)
Good point, Cuddlyable. Unfortunately, few people bother to learn the names of true American heroes like Lewis and Clark, Davy Crockett, Charles Lindbergh, Amelia Earhart, John Glenn, and Buzz Aldrin anymore; instead, they learn all the names of the latest trashy, slutty celebrities like Britney Spears, Christina Aguilera, George Michael, Snoop Dogg, Alec Baldwin, George Clooney -- you name it. In fact, this generation's (MY generation's!) knowledge (or lack thereof) of American history is perfectly shocking. Maybe that's the reason why God told me to write historical ballads. I wouldn't be surprised if most people my age thought that the Alamo was only a car-rental company... :-) 76.21.37.87 (talk) 02:12, 19 July 2009 (UTC)
Just for fun, and as an example of what I mean, here's an actual student's answer to an actual teacher's in-class question (I got this from the website www.stupidest.com): Teacher: "Who was the first man to walk on the Moon"? Student: "Louis Armstrong". :-) 76.21.37.87 (talk) 02:17, 19 July 2009 (UTC)
- Something is terribly wrong when a great american hero such as the first moon walker is unsung. Cuddlyable3 (talk) 21:35, 20 July 2009 (UTC)
- :-) 76.21.37.87 (talk) 03:40, 21 July 2009 (UTC)
- As an aside, the Moonwalk article says that the first moonwalker was Bill Bailey, not Michael Jackson... 76.21.37.87 (talk) 03:44, 21 July 2009 (UTC)