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quotation
2012-Mar-24, 06:15 PM
Scientists at the Los Alamos National Laboratory campus of the National High Magnetic Field Laboratory have successfully produced the world's first 100 Tesla non-destructive magnetic field. The achievement was decades in the making, involving a diverse team of scientists and engineers. The 100 Tesla mark was reached at approximately 3:30 p.m. on March 22, 2012.

https://www.youtube.com/watch?v=N0R8dyyXtTo&list=UUbWmiA_pHk9DE62BaSUFFRw&index=1&feature=plcp

publiusr
2012-Mar-24, 07:08 PM
I wonder what all might come from this..

noncryptic
2012-Mar-24, 09:22 PM
I wonder what all might come from this..

It's a record but not a scientific breakthrough. It does not open the door to exiting new possibilities.
Stronger fields (of shorter duration) have been produced in the past.

Gsquare
2012-Mar-25, 09:35 PM
Stronger fields (of shorter duration) have been produced in the past.

True, but it also blows up the magnet. At least this one can be used again; that's why they call it a "non-destructive" field. :)

G^2

ddubs
2012-Mar-26, 12:01 PM
I wonder what all might come from this..

Massive railguns!

publiusr
2012-Mar-31, 07:02 PM
Space arks too. Maybe now maglev
http://www.geeky-gadgets.com/startram-is-cheap-alternative-to-rocket-based-space-travel-10-03-2012/

Then too...ah...from the bad old SLI days...
http://www.g2mil.com/others.htm

DoggerDan
2012-Apr-04, 03:18 PM
Space arks too. Maybe now maglev
http://www.geeky-gadgets.com/startram-is-cheap-alternative-to-rocket-based-space-travel-10-03-2012/

Then too...ah...from the bad old SLI days...
http://www.g2mil.com/others.htm

The second link says there are no engineering hurdles for RLV, and cites the Navy's successful testing of 130,000 lb payloads accelerated to Mach 4 at their China Lake testing grounds. The first link says StarTram is viable, and has passed Sandia Lab's initial review. However, the structure in the pic looks like an artist's rendition, not a properly engineered structure.

In the fifties, a lot of people proposed launching vehicles by maglev up the side of a mountain. We have 53 14ers here in Colorado, but there is, at most, only about two miles worth of acceleration space up the side of a mountain.

Instead, has anyone thought about digging a 10 to 20 mile tunnel with a gradual upward-curving slope that eventually has a final exit near the top of one of those 14ers? Look at the Chunnel: 30+ miles long and 25' wide. Mach 4 would play havoc with a vehicle inside, unless both ends were capped with a thin shield capable of holding back air pressure, but also capable of being pierced by a specially-designed cutter on the nose of the rocket. In fact, the air pressure itself might help propel the vehicle somewhat, so long as it wasn't going very fast (200 fps?) when it first entered the tunnel and a skirt was used as a seal between the air pressure behind it and the vacuum in front of it. The skirt would fall off as the rocket passed Mach 1.

At 14 psi differential, a 25' radius plug would initially experience 989,601 lbs of thrust. That's not much compared to Apollo or the STS, but they were also carrying fuel for the acceleration. As velocity increased, that would drop off, but it might be a welcome assist to the maglev thrust.

Assuming it pops out of the side of the mountain at 12,000 feet. What velocity can it sustain at that low of an altitude? I would think Mach 5 would be pushing it. That's just 3,500 mph, and it still has to accelerate to over 17,000 for orbit, so energy-wise, it's not all that far ahead of a launch from the cape, is it?

ravens_cry
2012-Apr-04, 05:05 PM
Instead of a cutter and a physical barrier, why not use plasma windows (http://en.wikipedia.org/wiki/Plasma_window#cite_note-0)?

HenrikOlsen
2012-Apr-04, 05:50 PM
Instead of a cutter and a physical barrier, why not use plasma windows (http://en.wikipedia.org/wiki/Plasma_window#cite_note-0)?
Because plasma windows are no use against pressure, they're for stopping cosmic rays, completely different problem.

ravens_cry
2012-Apr-04, 11:41 PM
Because plasma windows are no use against pressure, they're for stopping cosmic rays, completely different problem.
Actually, according to the link, that's EXACTLY what they (http://www.techbriefs.com/content/view/1834/32/) are good for. What you're thinking of is a plasma SHIELD.

HenrikOlsen
2012-Apr-05, 08:58 AM
Actually, according to the link, that's EXACTLY what they (http://www.techbriefs.com/content/view/1834/32/) are good for. What you're thinking of is a plasma SHIELD.
The link in the referenced post is to a New Scientist article about using a layer of plasma to protect against cosmic rays, that's what I commented on, as that was the link provided.

Anyway, I read the plasma window patent, they're talking about a window with a diameter of 2.6 mm, I suspect the principle is not going to work if you need one in the meter range.
For one thing, the force of the atmosphere will be on the order of a million times stronger.

ravens_cry
2012-Apr-05, 10:02 AM
Yeah, I accidentally linked to that citation rather than the main Wikipedia article. My bad.
I'll admit they are hungry beasts, but hitting pretty much anything at Mach 4 can't be good either.

publiusr
2012-Apr-07, 04:38 PM
Rockets can be said to have a pop-up trajectory. They are "slowest" where the atmosphere is thickest. Go pretty much straight up, and don't spend any more time in atmo' than you have to. Airbreathing complicates matters.