Question on Ocean Depths (random Wheels question)

So I was reading that the Marianna Trench is the deepest part of the ocean. But I also was reading that only a small fraction of the oceans have been mapped, in particular mapped from depth measurements. They don't know what geography lies under much of the ocean (they know the surface of the Moon and the surface of Mars better than the surface of the Earth). So my question is, with so little known of the oceans, how do they know the Marianna Trench is the deepest? Or do they just mean it is the deepest point discovered thus far?

I honestly don't know but I want this to become a weekly feature.

 

Is it the fact that they dont know the depths? Or more the fact that they dont know the details of the depths. They can use sonar and stuff to figure out how deep it goes when boats pass over, but they cant actually see what is down there due to the pressure and darkness is my guess. Id love to be able to explorer the deepest parts of the ocean, and survive. God only knows what creatures are living down there....

I hear Loch Ness lives there and drives a sub F458

They use sonar to map the ocean floor and yes, most of it has been mapped. The resolution of the map is of course limited to some degree. Don't expect Street View of it any time soon. I'm sure they are always trying to get better pictures with better equipment and such scientific research, but I think the detail of the map is good enough for human purposes.

 

It is both the deepest part of the ocean and, technically, the deepest part discovered. Trenches are the deepest spots and occur between two tectonic plates (I think.) Since they know where the plates are, they know where the deepest spots are.

I hear Loch Ness lives there and drives a sub F458

How can an expanse of water drive a sub?

They use sonar to map the ocean floor and yes, most of it has been mapped. The resolution of the map is of course limited to some degree. Don't expect Street View of it any time soon. I'm sure they are always trying to get better pictures with better equipment and such scientific research, but I think the detail of the map is good enough for human purposes.

 

It is both the deepest part of the ocean and, technically, the deepest part discovered. Trenches are the deepest spots and occur between two tectonic plates (I think.) Since they know where the plates are, they know where the deepest spots are.

 

 

 

Actually, they have been adding it to Google earth. More info here: http://earth.google.com/ocean/

 

They use sonar to map the ocean floor and yes, most of it has been mapped. The resolution of the map is of course limited to some degree. Don't expect Street View of it any time soon. I'm sure they are always trying to get better pictures with better equipment and such scientific research, but I think the detail of the map is good enough for human purposes.

 

I had read that in using sonar to map the depths of the ocean, that it would take 125 years with current technology to do this, because boats are slow-going...? How have they been able to map most of it thus far?

 

It is both the deepest part of the ocean and, technically, the deepest part discovered. Trenches are the deepest spots and occur between two tectonic plates (I think.) Since they know where the plates are, they know where the deepest spots are.

 

I see, that is very interesting.

Is it the fact that they dont know the depths? Or more the fact that they dont know the details of the depths. They can use sonar and stuff to figure out how deep it goes when boats pass over, but they cant actually see what is down there due to the pressure and darkness is my guess. Id love to be able to explorer the deepest parts of the ocean, and survive. God only knows what creatures are living down there....

 

http://www.deepflight.com/ - someday I'd love to buy one of these.

God only knows what creatures are living down there....

 

 

As much as I'd want to see crazy huge dinosaur looking creatures, my diving experience and little physics make me think the answer is most likely:

 

 

flat and tiny.

 

 

 

 

 

 

 

However, doesn't mean they aren't cool. Here is a water flea:

 

 

 

 

 

 

 

 

 

I'm pretty sure the Navy knows in detail the depth of most of the ocean, especially for submarine navigation.

As much as I'd want to see crazy huge dinosaur looking creatures, my diving experience and little physics make me think the answer is most likely:

 

 

flat and tiny.

 

 

 

 

 

 

 

However, doesn't mean they aren't cool. Here is a water flea:

 

 

 

 

Well there are always the giant squids and shit that are super deep we dont see until they come up to die sometimes. who knows how big some of the live ones are swimming around down there.

 

Reading more about that deep sea flight thing is awesome. I couldnt imagine what it must be like at 36,000ft down in a sub!

The Lambo of the underwater world:

 

I saw something on this on Discovery a few weeks ago. Apparently the first autonomous sonar submersibles are just now being used. But even the one that generated more mapping of the ocean than we ever had before failed at depth (insta-crush) after a few months.

I know there are a few troughs in the world where Submarines converge.

 

See this http://news.bbc.co.uk/1/hi/uk/7892294.stm

 

Branson has just anounced his personal dive ship that can take one person down to over 35000 feet !!

Just can't really see how creatures can live in there pressures. 10000 meters is 1000bar pressure!!