149 replies to this topic

[Siguy]

My, what happened to this thread?

I was just rummaging around the science and tech part of msn and found this little piece about the Fallacy of a "full" moon. Article.

Also, I've been keeping up with the Mars rover too. All it's findong of something white. What do you all think it is? Salt or Ice?
I think it's salt.

Another thing I've been reading is the discovery of 3 super Earths. I honestly think it specatacular that they can find these things. But man, it's takes 'em so long to conclude this stuff. Kinda makes me wish we had the abitity of light speed or even superluminal speeds. 46 lights years away. If I'm mistaken that would take 46 years to get to at the speed of light. Not too out of sight, if we could move that fast.
That being said, do you think it's possible to achieve luminal speed? Or even superluminal speeds?
I've seen the thesi on this and I do believe it very possible if not for one factor that either doesn't exist or just hasn't been discovered yet.

Discuss.

It is perfectly possible, but we have no way to rapidly accelerate for long periods of time. Our fastest spacecraft use ion thrusters powered by radioisotope thermoelectric generators (electricity generated from the heat given off by radioactive isotopes) or solar panels. Those thrusters can run continuously, but they only produce a few grams of thrust, so it takes years and several gravitational slingshots for the spacecraft to reach full speeds. And of course, those are all robotic spacecraft.

For interstellar travel, I think conventional propulsion is out of the question. The fastest spacecraft that we can build with current technology are solar sails, which could reach extremely high speeds, but they take even longer to accelerate than (most) ion thrusters. Plus, they are only suitable for interplanetary, not interstellar travel. The only solar sail powered spacecraft ever made was Cosmos 1, which was launched in 2005, but the launch failed due to an outdated rocket and it never made it to orbit. Since then nobody's scraped up enough to build another one.

We still do not have the technology to reach light speed, let alone superluminal velocity. But if we could attain speed with out actually accelerating, then it would totally be possible.

I think we should probably work on improving the space program as it is right now, because its goals are a bit messed up. I want to go to Mars at some point in my life!

[Eurysilas]

I'm quite sure it's not possible to go faster than the speed of light. Nothing observed yet has been able to, and last time I read a physics book, didn't Einstein's equations break down into complete nonsense at those speeds? I do, however, think it is possible to "cheat", and fold space. But what might be the effects of doing such a thing? I don't mean to paint an alarmist's picture, but folding space does us diddle bit of good if it, say, permanently damages space-time along the trajectory which we travel, or something equally catastrophic.

I'm interested in what the Large Hadron Collider will find in regards to the Higgs field, actually. It might answer whether we're just not seeing what goes faster than the speed of light.

[Siguy]

It isn't impossible for something to go faster than light, it is only impossible for something to accelerate to the speed of light and beyond. So if something is created going faster than light, then it it is going faster than light and you can't really argue. Also, the speed of light isn't constant.

[Eurysilas]

Also, the speed of light isn't constant.

True, it varies depending on the medium it goes through. When they say they haven't observed anything going faster than light, they must mean light in a vacuum.

So, it's not impossible to start out at the speed of light? Interesting, but it still does us little good, since we can't create matter.

[Rocksfan13]

Hey guys. More news today.

Article.

Apparently they've found water in samples from the moon from the 60's. Wow. It took us this long to find this stuff?
Anyway, they seem to think this find is going to reshape they way they think of missions to the moon and possibly colonizing it.
Call me crazy, but I really don't think they're gonna find enough water, at least they way they have found it, to make a huge difference.
I dunno. What do you guys think?

[Red Phazon]

Big post ahead. I'll get to the new article later, but I missed out on the last one.

I was just rummaging around the science and tech part of msn and found this little piece about the Fallacy of a "full" moon. Article.

Well in that case, the moon is only full for an instant specific to your exact location.

Also, I've been keeping up with the Mars rover too. All it's findong of something white. What do you all think it is? Salt or Ice?
I think it's salt.

Are you talking about this?

Another thing I've been reading is the discovery of 3 super Earths. I honestly think it specatacular that they can find these things. But man, it's takes 'em so long to conclude this stuff. Kinda makes me wish we had the abitity of light speed or even superluminal speeds. 46 lights years away. If I'm mistaken that would take 46 years to get to at the speed of light. Not too out of sight, if we could move that fast.

I heard about these, but somehow I was not able to find anything on them at all, but then again, I didn't search using the term super Earths. I'll try again later.

That being said, do you think it's possible to achieve luminal speed? Or even superluminal speeds?
I've seen the thesi on this and I do believe it very possible if not for one factor that either doesn't exist or just hasn't been discovered yet.

Light can only travel at the speed it does because it has to in order to regenerate itself. Otherwise it would die out instantly. That being said, we'd need to meet the same conditions to reach that speed, but I'm only speculating. As for going faster, no it isn't possible (Relativity, I think? I'm not certain). The speed of light is ultimate.

It isn't impossible for something to go faster than light, it is only impossible for something to accelerate to the speed of light and beyond. So if something is created going faster than light, then it it is going faster than light and you can't really argue.

Okay, maybe I should have read this first. I don't know enough, but in the back of my mind I recall from somewhere, that faster speeds than light defies known physics. Then again, relativity and quantum mechanics aren't complete, and may never be.

Also, the speed of light isn't constant.

The speed of light itself is constant. Light appears to move at different speeds in different material because it takes longer for the atoms to absorb and re-emit the light. It mostly depends on density, I think.

[vravelo]

Wow..! A black hole here at ZC where I can land to ask questions "scientific question"
Ok only this question,
I personal don't believe in UFOs, or first class encounter , or Alien, etc etc
But can any one post a question related to this matter in here...? and will be answered ?
thanks

[Siguy]

A brief figure for conversation that I just calculated.

If you had a spacecraft capable of continuous acceleration of 1 g, it could reach Mars (at opposition) in 8 hours. If the cabin was layed out perpendicular to the flight path, it would also have simulated gravity. Imagine that.

Unfortunately, there really isn't any kind of propulsion we have that can accelerate a spacecraft at 9.807 m/ss for 8 hours. A typical MPD thruster can produce fifty pounds of thrust, better than the typical one fiftieth of most ion engines, and could be upscaled, but such a thing would probably require power in the gigawatt (yes, that's right, jiggawatt, Back to the Future fans) range. Only in science-fiction are there sources of that much power that could feasibly fit on a spaceship. Solar panels wouldn't generate anywhere near enough energy, neither would radioisotope thermoelectric generators. A nuclear fission reactor would be ridiculously heavy. Sorry, but even the house sized donuts of experimental fusion reactors can't yet produce a watt of usable energy, so until further research has been done, fusion power generators are sci-fi. But really, so is the rest of the idea.

Any thoughts?

[Eurysilas]

Well, I think that perfecting some sort of fission process will be our best bet. It produces ENORMOUS amounts of energy, so all we'd need to do is refine the process to make it less dangerous and more miniaturized. I guess you could say I'm a fan of the "work with what you have" philosophy, as I think it imperative that we become a space faring civilization as soon as possible. We're just too vulnerable as it is (to a planet-killing asteroid or to over population).

[Rocksfan13]

I believe our best bet is with matter / antimater infusion. It's clean, wates nothing and coverts to pure energy. However, we are able to produce enough antimatter here on Earth to build such a device. But I believe that one day we will find a way.

But I agree. We need to extend to the stars.

[Chii]

So this is the science thread? Well, here's something for everyone to be excited about:
http://www.comcast.n...1/Phoenix.Mars/

THEY FOUND WATER ON MARS!!!!!

[Rocksfan13]

I'm honestly not surprised. Mars does have polar caps of ice. It's the fact that there may have been viable life on that planet that intrigues me.
I'm sure they'll find water elsewhere as well, just in a different form.

[Siguy]

Of course there's water (ice) in other parts of the solar system. It's been known for quite some time. For example, Encelaedus has a thick crust of ice and possibly a subsurface ocean, as well as Europa or Ganymede (can't remember which.)

[Silver]

It's Europa. Check this out:

At just over 3,000 kilometres (1,900 mi) in diameter, Europa is slightly smaller than Earth's Moon and is the sixth-largest moon in the Solar System. Though by a wide margin the least massive of the Galilean satellites, its mass nonetheless significantly exceeds the combined mass of all moons in the Solar System smaller than itself. It is primarily made of silicate rock and likely has an iron core. It has a tenuous atmosphere composed primarily of oxygen. Its surface is composed of ice and is one of the smoothest in the Solar System. This young surface is striated by cracks and streaks, while craters are relatively infrequent. The apparent youth and smoothness of the surface have led to the hypothesis that a water ocean exists beneath it, which could conceivably serve as an abode for extraterrestrial life. Heat energy from tidal flexing ensures that the ocean remains liquid and drives geological activity.
From Wikipedia

I think that the bold points make it habitable for human life-I mean, Europa has oxygen and water-just what humans and other organisms need to live on Earth!
But then again, it has a temperature of 102 K, which is approximately -171 degrees Celsius, or -275 degrees Fahrenheit(correct me if I'm wrong).
There's also the distanse factor to consider as well.
Someday...

[Alestance]

We have creatures in our deepest oceans. Also, if geothermal vents on the moon exist within those hypothetical oceans, life can possibly exist there. However, I don't believe we'll be able to find out in our lifetime. The odds are in our favor, though. That I believe.