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[BioWareM0d13]

Hot Neptune' sports a tail millions of kilometers long

 

 

Ken Croswell 24 June 2015 1:00 pm 

 

The Hubble Space Telescope has discerned signs of distress in a world 33 light-years away. The planet is as large as Neptune but hotter than Mercury, whirling around a red dwarf in the constellation Leo named Gliese 436 every 2.64 days. When the planet passes in front of its sun, astronomers report online today in Nature, hydrogen atoms spewing from the planet's atmosphere obscure 56% of the star's disk and absorb its ultraviolet light. As shown in this artist’s conception, the hydrogen atoms form a tail resembling a comet's that stretches millions of kilometers behind the planet, which the astronomers estimate has lost up to a tenth of its original atmosphere. In more extreme cases—when a Neptune-sized planet is closer to its sun and thus even hotter—it may shed so much material that it becomes a rocky world like Earth, albeit far hotter than the planet we call home.

 

Sciencemag.org

[bEVEsthda]

This article from yesterday - thought it would be better to put it here than try and revive my previous EM Drive thread:

https://hacked.com/s...ive-propulsion/

So, contrary to the article's title, the team from Germany was able to build a prototype that did generate thrust as is predicted by EM Drive theories, although it still appears to be violating conservation of momentum as well as a few other known laws of physics. Basically, the result is "we are seeing thrust that we can neither explain nor understand."

The beautiful thing about the EM Drive is that it generates thrust from microwaves, meaning electricity alone can generate thrust, even in the vacuum of space. This means that:

1) No liquid fuel is needed (power could. E provided from a solar panel array, a nuclear reactor or some other form of reusable, long term energy source), so that means we've got much less weight sacrificed just to get into orbit, meaning the age old problem of returning from landing missions is potentially alleviated. Let's go manned missions to Mars!

2) Space travel is potentially exponentially faster - conventional thrusters use lots of fuel in the vacuum of space to produce negligible thrust. The EM Drive is generating thrust in a vacuum, meaning it will push just as hard in space as it would in Earth's atmosphere. This means that, despite the completely unknown reason why, we are able to travel much faster than a rocket would ever have before (although this is not a Warp drive - we are not breaking FTL speeds here).

3) It is cheap. Basically a magnetron (which you can find in your microwave) that is properly calibrated and attached to a VERY carefully constructed fulstrom can generate 400 Newtons/100kW. The current scale wouldn't be great for a satellite, but you get fifteen to thirty of those babies strapped to a craft and you can go zipping around the solar system, sun to Pluto, in a matter of months.


Pretty exciting stuff. Still, since the mechanics are still widely misunderstood and it seems to still violate established laws of physics, there is a lot of skepticism and no one rushing to build anything aside from uber-science DIY'ers. Still, very interesting news all around.

 

Assuming that this turns into a viable result/technology, *fuel*  ("No liquid fuel is needed")  is still (I've made this point before) an incorrect term. No reaction-mass alt. propellant is needed. Since solar panels will be unpractical for this purpose almost already at Mars, I think we are looking towards nuclear reactors, and they do need fuel. Even solar panels need fuel, it's just that it's already being burned in a remote location anyway, i.e. the Sun.

 

Having for the first time seen a drawing of how this is supposed to work, I'm very, very concerned that this might only be caused by interference with the Earth's magnetic field. And so are the scientists, I gather, as I note their desire to repeat the experiment with better magnetic shielding.

 

In any case, it doesn't violate conservation of momentum. That can be taken as pretty certain. A more reasonable theory is that it interacts with a mass that is relatively too big to observe in the experiment. Just the same as when a car is driving along, or you're walking.

 

Finally, even given a generous estimate of 400N per 100KW, this would be utterly useless for anything other than space travel. But if it does work, in vacuum and outside significant magnetic fields, then even 40N per 100KW is still brilliant news for deep space exploration.

[bEVEsthda]

P.S. Edit: I apologize for this post here. I thought I was in one of the general science threads. Oops!

 

 

Meantime, I've been arguing that the limits for Moore's law are much farther away than people always think they are, since 1991-'92 something (so I have a perspective of people's mobile pessimism on this issue). Sofar, I've always turned out to be right.

(We are slowing down though, no doubt about that. The doubling every 18'th month has become more like doubling every 30'th month.)

 

What is kinda slowing down things now (as we see them in commercial applications) IMO, are probably not technological/physical limits, but less intense competition.

 

There are, loosely estimated, something like a dozen of technologies to increase performance by magnitudes, which have hardly been touched sofar, because there have been no need. Technology first advance along the most accessible or well known paths.

 

None of these technologies are new. Nor do they signal any dramatic breakthroughs. These things have been steadily moving ahead for a good while. The links are just to update you on a few things which are rather 'real', unlike the wild cackle in popular science publications (i.e. optical computers, quantum computers, biological computers...).

 

https://hacked.com/h...chips-stanford/

 

(Early stacked architecture chips are already made by AMD and Sony, and I believe Intel is actually ahead of everybody, even if we don't see a commercial product yet.)

 

https://hacked.com/i...hip-technology/

 

(TI demonstrated 10 nm technology many years ago, and Intel is introducing 14 nm into commercial mass production as we speak, and are certainly looking ahead at commercial 10 nm.)

 

https://hacked.com/r...t-memcomputers/

 

(This is more of a complementary technology, just like neural processing.)

[bEVEsthda]

The conditions on Venus are rather depressing for us who want to see mankind exploit new worlds.

...Or are they?

 

https://hacked.com/n...-flying-cities/

 

 

Funny enough, the corresponding planet in KSP is called Eve, and is equally depressing. Landing a probe on it is easy enough, but the atmosphere and temperature makes it pretty hopeless to consider solutions for getting away from the planet surface again, or having Kerbals survive. Funny, because the idea of staying higher up, and the idea of using baloons, did occur to me. Only, KSP doesn't have any components to support building such machines. Yet. And sofar I don't use any Mods at all.

[Fast Jimmy]

Assuming that this turns into a viable result/technology, *fuel* ("No liquid fuel is needed") is still (I've made this point before) an incorrect term. No reaction-mass alt. propellant is needed. Since solar panels will be unpractical for this purpose almost already at Mars, I think we are looking towards nuclear reactors, and they do need fuel. Even solar panels need fuel, it's just that it's already being burned in a remote location anyway, i.e. the Sun.

We're on a video game forum, dude - layman's terms are best. Long story short - a nuclear reactor or solar panels are infinitely easier to travel with over conventional rocket fuel.

Having for the first time seen a drawing of how this is supposed to work, I'm very, very concerned that this might only be caused by interference with the Earth's magnetic field. And so are the scientists, I gather, as I note their desire to repeat the experiment with better magnetic shielding.

In any case, it doesn't violate conservation of momentum. That can be taken as pretty certain. A more reasonable theory is that it interacts with a mass that is relatively too big to observe in the experiment. Just the same as when a car is driving along, or you're walking.

The shielding is a concern (and unfortunate, honestly), but this is now the fourth published paper from a credible science institution that is observing this phenomenon. Other experiments had better shielding, others used different fulstorm casing designs, others different magnetron values... but all have reported thrust. These are peer reviewed articles that have long ago dismissed Earth's magnetic field as the culprit.

Finally, even given a generous estimate of 400N per 100KW, this would be utterly useless for anything other than space travel. But if it does work, in vacuum and outside significant magnetic fields, then even 40N per 100KW is still brilliant news for deep space exploration.

The 400N per 100kW is not generous, but a reported value, seen from the Chinese team (Yang et. al) performing similar work. And given the size of the EM Drives created so far, any application (space or terrestrial) would need to have an array of such drives, not just a single unit.

[bEVEsthda]

We're on a video game forum, dude - layman's terms are best. Long story short - a nuclear reactor or solar panels are infinitely easier to travel with over conventional rocket fuel.

And given the size of the EM Drives created so far, any application (space or terrestrial) would need to have an array of such drives, not just a single unit.

 

Please, just use 'propellant' instead. 'Fuel' is not a layman's term. It's an incorrect term. It's hard enough as it is to have people understanding energy concepts.

 

Assuming a 10 tonne probe (that should be a pretty complex and capable probe and maybe also able to generate 100 KW), 400 N would give it an acceleration of 0,04 m/s^2. In just 30 days this would reach a speed of 373,248 Km/h. The launch speed of New Horizon was "only" 57,600 km/h, making it the fastest Earth launch ever.

And assuming we have some isotope reactor on that spacecraft, there's no reason to turn the drive off after 30 days. The reactor will last a definite time whatever. So we could accelerate for half the trip, decelerate for half, be at Pluto in a Jiffy, instead of after more than nine years, stay at Pluto, go into orbit, go into low orbit, maneuver as we please, go into orbit around Charon, send down a small lander, take surface sample, whatever, liftoff and dock with probe again, start a return journey and be back at Earth in another jiffy. We could even reuse the spacecraft for other missions. Many more other missions.

 

That's why I said even 40 N would be brilliant news.

[Fast Jimmy]

Please, just use 'propellant' instead. 'Fuel' is not a layman's term. It's an incorrect term. It's hard enough as it is to have people understanding energy concepts.

Assuming a 10 tonne probe (that should be a pretty complex and capable probe and maybe also able to generate 100 KW), 400 N would give it an acceleration of 0,04 m/s^2. In just 30 days this would reach a speed of 373,248 Km/h. The launch speed of New Horizon was "only" 57,600 km/h, making it the fastest Earth launch ever.
And assuming we have some isotope reactor on that spacecraft, there's no reason to turn the drive off after 30 days. The reactor will last a definite time whatever. So we could accelerate for half the trip, decelerate for half, be at Pluto in a Jiffy, instead of after more than nine years, stay at Pluto, go into orbit, go into low orbit, maneuver as we please, go into orbit around Charon, send down a small lander, take surface sample, whatever, liftoff and dock with probe again, start a return journey and be back at Earth in another jiffy. We could even reuse the spacecraft for other missions. Many more other missions.

That's why I said even 40 N would be brilliant news.

If you are truly curious and want to apply a critically scientific eye, here is a thread that best documents all the known findings and designs of the concept:

http://forum.nasaspa...p?topic=37642.0

I don't Science nearly well enough to pretend I understand 2/3's of it, but that would better answer any questions more than I or the Tajmar paper could.

[bEVEsthda]

If you are truly curious and want to apply a critically scientific eye, here is a thread that best documents all the known findings and designs of the concept:

http://forum.nasaspa...p?topic=37642.0
 

 

I've only sort of skimmed some of it.

But I'm now more pessimistic (even if I didn't really dare to believe it before). We'll see eventually, because now experimenting and interest seem to be growing. But there are a few things that are disappointing:

 

The measured thrusts are very, very small. This means that there might not really be a positive result. It might be illusive. It may be all kinds of different phenomena giving those readings.  So far a number of possible causes have not been completely ruled out. The measurements do not seem to correlate to theory. That's a bad sign. Hopefully, there is a mystery in there, and that mystery will hopefully turn out to be that the EM drive actually do work. But I wouldn't bet money on it. Sorry.

 

Also, the previously discussed 400 N from 100 KW is very generous. The best perceived thrust so far only corresponds to 100 N from 100 KW, but since that reading is so very small, there's a great deal of uncertainty.

 

Well, I hope, but not much.

[LPPrince]

Great livestream right now, in space- http://www.nasa.gov/...satv/index.html

[LPPrince]

And history has been made on that livestream as astronauts on the ISS harvested and consumed the first ever space-grown produce(red romaine lettuce).

[Fast Jimmy]

And history has been made on that livestream as astronauts on the ISS harvested and consumed the first ever space-grown produce(red romaine lettuce).

Did they give any comment on how it tasted?

[LPPrince]

Did they give any comment on how it tasted?

 

Like arugula, one said. Other than that, good.

 

They tried it alone at first, then added extra virgin olive oil and vinegar, or some sort of Italian vinaigrette.

[Fast Jimmy]

Like arugula, one said. Other than that, good.

They tried it alone at first, then added extra virgin olive oil and vinegar, or some sort of Italian vinaigrette.

Lol Well, that's good.

Unless the undetectable space microbes are now living in their body, waiting until they return to Earth to awaken and devour the planet. In which case, that's bad.

[LPPrince]

Lol Well, that's good.

Unless the undetectable space microbes are now living in their body, waiting until they return to Earth to awaken and devour the planet. In which case, that's bad.

 

Still though, SPACE GROWN PRODUCE.

 

This is a necessity for long trips in space. They constantly mentioned the manned mission to Mars needing this.

[Fast Jimmy]

Still though, SPACE GROWN PRODUCE.

This is a necessity for long trips in space. They constantly mentioned the manned mission to Mars needing this.

Although it would be quite different for Mars. There they would have gravity, just not as much as Earth. And they would need to develop a way to grow the food outside of hydroponics, since they require a lot of water and resources that would need to be directed towards basic survival on Mars.

Still - very good. I love the strides we've been taking in the last few years towards sustainability on other worlds. This is great news.

[Katiefrost]

Life at the space station gets a little bit easier with improved coffee technology:


http://edition.cnn.c...s/out-in-space/






The behavior of fluids in zero gravity is really intriguing.

[bEVEsthda]

Everything important solved then. - Let's go to space!

[Fast Jimmy]

Everything important solved then. - Let's go to space!

Salad and coffee - we'll take care of the rest on the way!

[LPPrince]

Salad and coffee - we'll take care of the rest on the way!

 

Why not.

[Katiefrost]

Salad and coffee - we'll take care of the rest on the way!

We'll need chocolate too. Chocolate may become earth's interplanetary currency if we meet anyone alone the way.

[Fast Jimmy]

Why not.

In order to get max Victory Points, the spaceship to Alpha Centauri has to be as pimped out as possible. Preferably before 2020.

[Katiefrost]

I didn't really consider the necessity of cleaning the outside of the space station's windows, but they probably accumulate plenty of dust.

[The Devlish Redhead]

Lol Well, that's good.

Unless the undetectable space microbes are now living in their body, waiting until they return to Earth to awaken and devour the planet. In which case, that's bad.

 

 

Or if they had an asteroid nearby green slime....... OMG what a fun movie

 

 

 

I wish astronauts looked like her