RichF

http://www.smh.com.au/news/national/friday-13th-asteroid-a-close-call/2006/07/01/1151174439124.html

So on July 3 a 400 meter wide asteroid is to pass within 430,000 km of earth and another is predicted pass within 35,000 km in 2029.

There's been a lot of speculation as to what would happen if such an object hit the earth. My question is...what would happen if such an object hit the moon? Given that the moon has a smaller mass and does not have an atmosphere to protect it, would the mass of such an asteroid be sufficient to change the moon's orbit, cause a large loss of mass or severly fracture the surface? Maybe we'd just get a really cool show...

Thanks,

Rich

I'd think that as a child, when you're already growing, you would grow a lot taller (and weaker) in a weightless environment because you're not fighting gravity, but I'm not sure how much or if that's even actually true. I don't think merely being weightless would cause you to grow if you weren't already, except what Tycho said.

A child may not grow at all; low gravity seems to cause a loss in bone density. According to NASA astronauts/cosmonauts on Mir lost 1-2% of their bone mass per month.

"The 1 to 2 percent per month loss is an estimate of bone loss -- an average value," Shapiro says. "Certain individuals on six month flights have lost as much as 20 percent of bone mass in their lower extremities, while a few have lost none during the same period in space."

Would a child be able to develop under such circumstances?

My diesel would put a Accord Hybrid to shame! Not to mention that I'm running off of 20% biodiesel and could run 100% if state regulations would allow it. Imagine that, running your car off of home grown crops, getting 40+ mpg, negligible emissions and helping out your fellow farmer! I've thought about setting up a reactor to convert used veggie oil into biodiesel but I haven't had the time or patience.

Now if you start talking hybrid diesel, my ears will perk up but the EPA has made that impossible for a few years....70-90mpg is what I've read. Here's to 2008!

Gas hybrid..big woop, lots of cash not that great of a return but I guess it's better than the alternative. Michelin holds an event every year if anyone is interested...."The Bibendum Challenge"....vehicle entries below.

http://gestdoc.webmichelin.com/repository/DocumentRepositoryServlet?codeDocument=2116&codeRepository=CHALLENGE&codeRubrique=docs_2006

I bet that I know a friend of yours. Ever been to PA? : P

Here's a thought to ponder. How long did it take for humans who migrated to Europe/North Western Asia to develope lighter skin, eyes and hair? It makes since that they would eventually due to the colder environment. I think that it's amazing that the human body can adapt/evolve to fit such a vast environment.

Adapt/Evolve can be considered an argument in itself. Do random mutations cause the adaption or does the environment encourage it? As stated before; I am not an expert here...just throwing stuff out.

RichF

The same genetic phenomenon is supposed to be the reason why people of African origin do so well at the Olympic games. It is not that Africans are 'superior'; just more diverse. With a broader normal distribution curve of athletic ability' date=' there will be more at the top to choose from.[/Quote']

 

Exactly!

 

A similar mechanism has been proposed for why humans today are taller and healthier than in Roman times etc. In times when wealth and technology were limited, so was travel. Thus, people tended to stay where they were born, and marry their neighbours. This led to a degree of inbreeding.

 

Today, people are likely to marry people from far away. Thus, less inbreeding and better genetic spread.

 

I've always heard that the short stature was due to malnutrition but you bring up a good point! I'm not sure what impact inbreeding has but I imagine that it occurred frequently especially in colder climates where travel was difficult for part of the year. Makes since to me!

Interestingly enough its well known that humans have generally grown taller over the past 2000 years or so. A male was considered tall in ancient roman times if he was 5'5". I learned this at a trip to one of the Smithsonian Museums a few years back. Prior to that, whenever I visited a museum with garments from antiquity (such as roman gladitor uniforms) I would get disappointed with the small sizes!! The armor looked as though it was made for hobbits.

I've always heard that was attributed to poor diets and a lack medical care...true?

I read a couple of studies several years ago that stated that the farther populations migrated out of Africa, the more isolated they became; this resulted in the populations being less diverse in physical structure. Basically the point was that even though the average height may be the same, the closer you get to the origin of humanity the more varied the physical build due to a more diverse gene pool......ie, a greater percentage of tall, short, fat, thin....ect

Edited because I mutilated the English language while trying to multitask.

.......Or they'd realize that half of them were plaster reproductions.

They may come to the conclusion that dinosaurs were very medically advanced as they were able to repair fractured skeletons with plaster replacements. OMG, they were able to replace 75% of a fractured skull!!! :eek:

Yes, yes...that helps out a great deal! Thank you for the explanation.

Quick note for clarity. I understand how DNA maps organ and body structure but behavioral mapping is a little beyond me....

Have any studies been done on the topic?

Thank you but I am aware of how proteins work within the DNA structure and how it maps out which cells are to do what. My question revolves around how DNA is related to mapping synapses to create instinctual behavior.

Have any studies been done on this? Take my example in the previous post.....

Did a random mutation of an ancient feline relatives DNA create the need to cover the kitty poop?

Thanks in advance.

How are instinctual actions imposed by DNA? I've never really given it much thought but how does a kitten all of a sudden realize "Hey, that stuff looks good to poop in and maybe I should cover it up". Logically it makes since as it would help to hide the scent but the kitten doesn't know that. It's just doing what it's been programed to do.

So, how does this work? Do actions become instinct or do random brain mutations that work become instinct? Can an instinct be imprinted on DNA or is it the DNA that does the imprinting on the instinct?

When I get hungry I seek out food. Yes I know that is a primal instinct but where did it originally come from? A random act of mutation that happened to work out?

I'm not much of a biology guy so bear with me. Just my thoughts on a Monday,

Rich

I believe the climate is changing because of many factors' date=' however the main factors that I think are responsible are the following.

 

I am not a greenie however, The amazon rain forrest is being decimated every day by big corporations cutting down the old growth trees to use as tooth picks or somthing. This forrest is the largest oxygen factory on the planet and in particular the old growth trees. As a consequence of the reduction of these trees the Co2 levels are rising. Even though people are planting more and more trees everyday, it will take at least one hundred years before these new trees are able to filter out large amounts of Co2 from the atmosphere. [/quote']

 

You blame this on big corporations but the truth is that Amazon deforestation occurs becuse the Brazillian govt allows it. Maybe the UN should step in?

Are green house gasses bad...yes. Was the entire midwest and east coast of the US flooded at one time..yes. Was Canada, the entire north east and europe engulfed by glaciers several thousand years ago...yes. Personally, I don't think we are aware enough of the Earth's cycles to give a definate answer. This world has been here for 4 billion years and we presume to know everything about it from a 100 year record.

JMHO...pick me apart.

No, in fact as I recall one could build a primitive (but working) example of one with the old Radio Shack 150 and 1 breadboard sets and I could probably cobble something like that up too, but I am looking for a 'pro' model (as it were.)

I was speaking with an older neighbor of my grandmothers, in his eighties, about a month ago and I asked him if that was a telegraph up on his shelf. He said no and started to explain to me that it was a Crystal Radio. It had primitive headphones and a copper switch that you moved back and forth to change channels. Maybe this is something similar? Here's info on how to build one...

http://sci-toys.com/scitoys/scitoys/radio/ten_minute_radio.html

Well, he is a professor of Geology but I had a few nutty professors back in school. I'll take it with a grain of salt.

Anyways....what do you guys think of this one?

 

You may be interested to know that global warming' date=' earthquakes, hurricanes, and other natural disasters are a direct effect of the shrinking numbers of Pirates since the 1800s. For your interest, I have included a graph of the approximate number of pirates versus the average global temperature over the last 200 years. As you can see, there is a statistically significant inverse relationship between pirates and global temperature.

[/quote']

 

I would like to see some true data.

 

Bob Carter' date=' who wrote the article in the OP, has apparently[/quote']

 

I don't know much about the dude. Can you back that up or are you just pooping on the dude because it doesn't match your opinion?

the global mean surface temperature is a lousy metric for measuring radiative imbalance and that's all there really is to it

What would be the prefered method?

Oh boy, I love it!!! Very interesting read; love to hear your thoughts but please read the entire article before jumping to conclusion.

http://www.telegraph.co.uk/opinion/main.jhtml?xml=/opinion/2006/04/09/do0907.xml&sSheet=/news/2006/04/09/ixworld.html

Ha, so in order to cancel the effects of gravity, all you have to do is keep an equally massive object equidistant in the opposite direction to the local center of gravity. Put a stationary earth-mass black hole 4000 miles above you, and voila!

That's a very good idea; I'm going to start on that tomorrow!

Edit: I should have read this thread first.... http://www.scienceforums.net/forums/showthread.php?t=18462

Like I said...I was reaching.

'']But you dont artificially reproduce an electromagnetic field. You just create an electromagetic field, period.

Fair enough, I should have used a better choice of words. "Man made fields" would have done better.

My God! All you need to eliminate gravity is a magical anti-gravity machine that creates out of nothing a new fundamental force in large quantities?! Why didn't I think of that?

There is nothing new about gravitational force; matter creates a gravitational field which in turn applies a force on other matter. What causes matter to create the field is the question.

Edit: spell monster.

Has any force been "artificially reproduced" ?

Electro-magnetic.

'']Hows about creating a gravitational force that makes delicious pies? Not to sound like like an asshole, but just making up a force that does whatever you want doesn't really make sense in physics. You'd have to explain what causes such a force, how and why it works. So such an idea isn't so much far fetched as... not physics. Suitible for soft sci-fi perhaps.

Not asshole-ish at all. Gravity is a known force/field that causes mass to accelerate. If what ever causes gravitational fields can be discovered and artificially reproduced...there you have it. In 1900 if you asked a scientist if we could explain the energy behind the sun or yet reproduce it 40 some years later they would have said that you are crazy.

Far fetched I know but that's just me.

This may sound far fetched but how about creating a gravitational force in the opposite direction of the existing gravitational force? Acceleration would be the differance in the two.