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David Attenborough on how to save the planet

newtboy says...

I have always contended that the issue/problem is not a technical one, we've had the technology to stop polluting the atmosphere since before I was born, it's the will of humanity to address the problem before it's too late that's the insurmountable issue.

Spacedog79 said:

Nuclear energy is the only way we can do it, we can run the planet forever and do things cleanly and more densely to leave more of our planet for wildlife.

The trouble is almost everything we hold as common wisdom about it is completely wrong, using breeder reactors have enough uranium to run the planet forever leaving almost no waste and removing the possibility of big accidents which actually aren't as harmful as commonly believed anyway.

We have thorium too, and many designs of each that can do the job. In fact we have a wealth of of options, but also a decades old and highly effective PR campaign from the fossil fuel industry to convince us otherwise.

SpaceX Demonstration Mission-1 Highlights

BSR says...

If you ever get a chance to experience a rocket launch, go for it. Just the sound alone gives you an idea of the thickness of our atmosphere.

ISS Assembly Time-Lapse Animation

BSR says...

I'm guessing that as each piece is added, it is already orbiting with the station exactly whether it's attached or not.

The station does need periodic boosts as there is some drag caused by atmospheric changes by the sun.

Disclaimer: Not a rocket scientist

CrushBug said:

I wonder what all the orbital dynamics were like? I would guess that every addition would mean a change to the orbit/speed/etc. to keep the thing in the right place.

Insight Lands On Mars

To Catch a Predator - "Have a seat" Compilation

00Scud00 says...

While the video itself is interesting and I am all for busting sexual predators, there is something ghoulish about turning it into entertainment. Kinda like the "fair like" atmosphere described at some public executions back in the days when we had public executions.

Hypersonic Missile Nonproliferation

newtboy says...

All you mention are a far cry from sustained hypersonic powered atmospheric flight, which is what we're talking about here.

You mentioned a ramjet, but scramjet engines are hardly an incremental improvement, they're an entirely different class of jet engine. Ramjet engines only do around mach 2.5- 5, scramjets 4-8+ theoretically. What's needed for a viable weapon imo is the next iteration of dual mode ramjets that can do both with one engine, that's a long way off. Public scramjet engine tests have only been successful in a few short 5 second+- burns so far, launched with conventional solid rockets.

scheherazade said:

We have conventional missiles that hit hypersonic speeds for short periods. Aim54 fired at altitude checks that mark, and that's a 60's/70's tech missile.

The X15 did it manned, and that first flew in the late 1950's.

Why would Russia not be able to come up with something similar in the last half-century?


Re-entry from orbit is 4x hypersonic. Russia has plenty of experience with the effects.

The Russian p-270 was made in the 80's, and used a ramjet.
This new missile is an incremental improvement over tech they already posses. A higher speed ramjet missile. Hardly a stretch.

It's not like they are spamming the internet with updates just so you can see how they are doing.

-scheherazade

Net Captures Space Debris

BSR says...

If I understand what you're asking, full speed is relative. Anything in orbit is traveling at a fixed, known speed to keep it from falling back to earth or flying out into space.

Once drag is imposed on the object it will start to fall and it's course will change toward earth. It will start to fall faster and then burn up in the atmosphere upon reentry.

Interesting fact:

Let's say a gun is fixed to shoot a bullet parallel to the earth. At exactly the same time you shoot that gun, you drop a bullet from the same height as the gun, both bullets will hit the ground at the same time.

If that gun could shoot that bullet 7,500 MPH (+ -), it would never hit the ground if it wasn't slowed down by air resistance.

Hope this helps.

Mordhaus said:

I wonder if it can handle full speed?

Ladies.. here is why 99% of Guys don't approach you..

00Scud00 says...

So if they were just jerks she'd still be dating them then?

I can't help but think that in today's atmosphere this problem will only get worse as now men are afraid they'll be called sexual harassers if they so much as ask a co-worker out on a date.

Payback said:

Female friend once complained to me that all the guys she dates turn out to be insecure jerks. I asked her what is it about insecure jerks she finds attractive? She immediately got sensitive and said she likes men who know what they want and take control of a situation. I said, the most insecure people are the ones who try to control everything around them. Secure people, by and large, don't care and seem aloof. They lead, they don't dominate.

I was walled into the friend zone by that point so, meh. Whatevs.

Rocket In The Sky Plus Accident

Lendl says...

It was not a test launch. It was an instantaneous launch just after sunset to launch 10 satellites. The clock on the dash cam must not be set to local time.

https://youtu.be/wtdjCwo6d3Q

"SpaceX is targeting launch of Iridium-4 from Space Launch Complex 4E (SLC-4E) at Vandenberg Air Force Base in California. The instantaneous launch window is at 5:27 p.m. PST on Friday, December 22"


https://spaceflightnow.com/2017/12/23/spacex-launch-dazzles-delivering-10-more-satellites-for-iridium/

"The two-stage, kerosene-fueled rocket climbed into the rarefied upper atmosphere a few minutes following liftoff shortly after sunset at 5:27:34 p.m. PST (8:27:34 p.m. EST; 0127:34 GMT) from Space Launch Complex 4-East Vandenberg Air Force Base northwest of Los Angeles.

The Falcon 9 left a brilliant white plume of exhaust in its wake, catching rays of sunshine as it soared above the stratosphere. The ever-expanding plume left a teardrop-shaped mark in the sky, prompting countless social media posts from rush hour drivers and others who happened to catch an unexpected glimpse of the rocket’s trip to space."

spawnflagger said:

at first I thought, "why don't they do these test launches late at night when fewer people are out on the roads?" then I saw the timestamp at the bottom was ~1:30am.

Accident was here: Google Maps
Highway 10, between LA and Phoenix.

Jupiter Juno fly by

Nasa Tracking 2017 Weather by Imaging Aerosols

Nasa Tracking 2017 Weather by Imaging Aerosols

Pastor Jim Bakker Helps You Stay Alive During the Apocalypse

Climate Change Just Changed by 50%

vil says...

No. A new improved future predicting model does not change how much CO2 is being pumped into the atmosphere, how much is already there and how fast it can be absorbed. Since we are already heading for disaster this is just a change in the estimate of the size and speed of the impending disaster. Sort of how someone tied to tracks can not seek hope in the changing estimate of how long the train is and how fast it is going.

Tabs v(ersu)s Spaces from Silicon Valley S3E6

MilkmanDan says...

I thought it was pretty clear in the show that he knew she was using spaces instead of tabs because of the sound of her repeatedly hitting the spacebar at the beginning of each line (which depending in your editor/IDE might be done automatically).

They are in a small environment, (loosely?) collaborating on code. He's anal about tabs vs spaces, and can tell that she's using the "wrong" one because of the repetitive (and annoying from his perspective) sound.

Put programmers together in a confined space, and they'll grate on each other over style issues / noise levels / music / whatever. I find the show extremely accurate in portraying the general atmosphere or feel of software development, if occasionally accenting or misportraying some details in the interest of making it good TV.

Buttle said:

The film, however, makes no sense, because the only way you can find out about a fundamental disagreement on spaces v tabs is by opening someone else's file in your editor, and finding the indentation all messed up. It's not something you can tell by looking over a shoulder.



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