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Space Discussion Thread






I call bullshit. ANYTHING at 1800F would be glowing bright orange.

I know that carbon and tungsten won't glow that easily, and plenty compounds should be similar
Not sure how likely they would be to cover a planet, but the graphic may have very well been a misinterpretation of data.
 
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I know that carbon and tungsten won't glow that easily, and plenty compounds should be similar
Not sure how likely they would be to cover a planet, but the graphic may have very well been a misinterpretation of data.
I've heated a rod of graphite with a propane torch before(don't ask why) and I can assure that it glows. Haven't tried tungsten, but that seems unlikely to cover the surface of a planet anyway.
 
If something is black (as in a black body radiator) and about 1000 degrees c hot, it should better be glowing! Considering that emissivity and absorptivitty are equal at equal wavelengths, it cannot be different.

This does not mean that the planet cannot be very black though. It could be backer that coal. Then again, if you ever used a barbeque you might have noticed that coal will glow orange when hot - even at the point where it would still be pitch black if suddenly combustion was halted (i.e. removal of oxygen).

Then again, a lot of stuff is quite black. One example is the surface of our moon that absorbs around 90% of visible light. If you made a beach out of lunar surface material, people would certainly call that a (very) black beach, like ones made from vulcanic dust. It's about as dark as a newly laid good quality asphalt road.

Many people thing that the lunar surface is the color of sand/dust or something gray about as reflective, but that's just an illusion. If the moon were that reflective it would probably be about 5 times brighter to our eyes.
 
Has anyone here heard of the planetary game "Space Engine"? I just downloaded it about 15mins ago and it's simply amazing the distances in space and how interesting each planet is. I also get very intimidating when standing on one of Jupiter's moons and seeing this HUGE planet rise into the air! If anyone is interested in getting it, it's free! :yh:

-Alex

SpaceEngine is probably my all-time favorite "game", if you could call it that. IIRC it's rendered in a 10 gigaparsec cube. If your machine can handle it, I would HIGHLY recommend that you check it out, even if only to see the sheer size of it.

Here's a small compilation of my favorite screenshots and video clips that I've taken:

I never really intended on showing it to anybody, so sorry for some quality issues.

Elite: Dangerous is a similar game, though it has much more of a game-play aspect to it.


As for traveling to other star systems, I recommend you guys check out this. (It uses lasers!)
 
Lol, just posting what was told about the planet. There are tons of planets that orbit so close to their parent stars their "year" is only a few hours or days. It was actually found that this is quite common in the universe!

Edit: About the darkest planet. It is estimated to only reflect <1% of all the light it receives!

Crazy when you think of traveling at 65MPH here on Earth and wiz past stuff but in space that's like standing still! :eek:

-Alex
 
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I know that carbon and tungsten won't glow that easily

Bullshit. The coals of a campfire or charcoal grill? All carbon. The incandescent light bulb in your table lamp? Tungsten. It's a law of blackbody radiation.

If something is black...

It doesn't need to be black. Steel isn't black. Tungsten isn't black. The sun's hydrogen isn't black. EVERYTHING will glow orange when heated to 1000C.
 
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EVERYTHING will glow orange when heated to 1000C.

Everything that we currently know about. Quite a few elements and many compounds defy conventional reactions already. Heck, maybe we'll discover something that when cooled produces a full spectrum of visible color, and goes dark when heated. Seems absurd, but then there's water covering most of our own planet.

PZOl9yG.jpg
 
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Ain't it kinda sad when you think about WHY humans went to the Moon? Not for interest in space exploration but due to the Cold War :(

-Alex
 
Ain't it kinda sad when you think about WHY humans went to the Moon? Not for interest in space exploration but due to the Cold War :(

-Alex

But if you really think about it, it's not sad at all.

When tensions were high between Russia and the US, nuclear war could've broken out at any second, and a few times it almost did. But we held strong, and instead of killing each other, we had a technological race to see who could get to the moon first. For the first time, instead of trying to best each other at warfare, two nations tried to best each other in achievement. I see that as a huge step forward for mankind, not necessarily because we landed on the moon, but because we were able to refrain from destroying each other. The cold war opened up an era for space exploration, which promised to advance humanity even further. What's sad is what we've done with that opening.
 
But if you really think about it, it's not sad at all.

When tensions were high between Russia and the US, nuclear war could've broken out at any second, and a few times it almost did. But we held strong, and instead of killing each other, we had a technological race to see who could get to the moon first. For the first time, instead of trying to best each other at warfare, two nations tried to best each other in achievement. I see that as a huge step forward for mankind, not necessarily because we landed on the moon, but because we were able to refrain from destroying each other. The cold war opened up an era for space exploration, which promised to advance humanity even further. What's sad is what we've done with that opening.

Or haven't done,
Plus rep
Danny
 
Bullshit. The coals of a campfire or charcoal grill? All carbon. The incandescent light bulb in your table lamp? Tungsten. It's a law of blackbody radiation.



It doesn't need to be black. Steel isn't black. Tungsten isn't black. The sun's hydrogen isn't black. EVERYTHING will glow orange when heated to 1000C.

You've misunderstood me. Tungsten and carbon typically glow less visibly bright at higher temperatures than similarly dark materials. Carbon's a bit misleading due to reactivity in air, but tungsten lights up at a much lower temperature in air just the same way. Blackbody radiation admittedly does say that materials should but off roughly the same radiation characteristics for surface properties and atomic emission properties, so the difference never should be very big. Not the point though.

Blackbody radiation doesn't necessarily have to do with the brightness of a planet though. Of course it could be taken that way with submillimeter radio astronomy or far IR astronomy, but these planets are currently, typically found using near IR and visible analysis of the light from distant stars. Basically, they're looking at the reflection of the star's light and wouldn't necessarily be analyzing the "glow" of the planet which would be highly insignificant at a relatively low temperature of 1000C for most planetary materials.
 
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If you account for redshift, a 1000 celcius hot planet would still emit visibile light no matter what, unless it were made up of some material with very low emissivity in the visual spectrum, yet high emissivity in the infrared to gain this heat from its star - basically painted in 1000-degree-resistant radiator paint.

If such a planet transists its star there would still be a regular dip in light intensity of the star. Surfaces of typical stars (like our sun) are typically much higher than 1000 celcius.

Glowingly hot planets are not that unusual either - earth was one at some point before the crust solidified. In fact, if you peeled off the outer 1% of the earth as it now, it would basically be a glowing ball of lava once again.
 
I wonder if the 9th planet that they can't find is very dark, that would explain why they are having trouble finding it. They say it's mass should be about 10 times that of earth so it's not likely small.

As for some type of FTL drive, I wonder if there's a way to travel between two points but not through normal space or at least not in the normal way. If you could travel near lightspeed you can get somewhere really fast according to Einsteins time dilation theory (a well proven theory), not a way to travel though because you end up many years in the future. Maybe there's a way to slow how fast we travel through time while traveling near lightspeed. We also don't know yet if hyperspace exists (space of more than 4 dimensions), that could solve the problem if it exists. In some of our SciFi this requires jump gate technology with a jump gate at both the departure point and the destination, that would kind of screw things up. Maybe wormholes are possible, I suppose there could be a problem with that and they couldn't send people through it. I have no doubt there will eventually be some way that will work.

Alan
 
I wonder if the 9th planet that they can't find is very dark, that would explain why they are having trouble finding it. They say it's mass should be about 10 times that of earth so it's not likely small.

The new supposed planet is difficult to find more because it's so far out, and its orbit makes the search area huge. It's still going to be pretty dark in terms of the reflected light because of the distance though.

As for some type of FTL drive, I wonder if there's a way to travel between two points but not through normal space or at least not in the normal way. If you could travel near lightspeed you can get somewhere really fast according to Einsteins time dilation theory (a well proven theory), not a way to travel though because you end up many years in the future. Maybe there's a way to slow how fast we travel through time while traveling near lightspeed. We also don't know yet if hyperspace exists (space of more than 4 dimensions), that could solve the problem if it exists. In some of our SciFi this requires jump gate technology with a jump gate at both the departure point and the destination, that would kind of screw things up. Maybe wormholes are possible, I suppose there could be a problem with that and they couldn't send people through it. I have no doubt there will eventually be some way that will work.

Alan

I feel like wormholes would be our best bet if we could find a bit of actual data to support them, but we seem to be a long way off. If we did have to build "gates", it still might not be too bad if they didn't have to be made of a huge amount of material. We could send small robotic crafts on 50-100 year journeys that would be impractical for people to analyze a solar system and send information. Back on Earth, we could decide if we want the gate there or send the probe onwards.

The closest thing we've seen to something that acts like a wormhole is quantum tunneling, but that's about it. Tunneling is some real funky stuff worth a read.
 
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I feel like wormholes would be our best bet if we could find a bit of actual data to support them, but we seem to be a long way off. If we did have to build "gates", it still might not be too bad if they didn't have to be made of a huge amount of material. We could send small robotic crafts on 50-100 year journeys that would be impractical for people to analyze a solar system and send information. Back on Earth, we could decide if we want the gate there or send the probe onwards.

The closest thing we've seen to something that acts like a wormhole is quantum tunneling, but that's about it. Tunneling is some real funky stuff worth a read.

Yes and it would be great if we could artificially create temporary wormholes between 2 points. I suppose there would be a problem with that like too much power required. Maybe they will be able to create micro wormholes that could be used for communication or to send probes through.

Alan
 





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