Starship Asterisk*

by **Chris Peterson** » Mon Feb 16, 2015 5:48 am

Steve Dutch wrote:This is a VERY late post. Like a number of people, I doubted that a lighter than air craft could work on Mars, except for one thing. Mars' atmosphere is carbon dioxide, molecular weight 44. That makes it much denser than nitrogen, molecular weight 29. So you could fill the blimp with nitrogen, with enough extra pressure to maintain its shape, and it would still float. I suspect it would be really flabby, but it would still float. In fact, you don't even need to ship air from Earth. Strip off oxygen from the CO2 to make CO, molecular weight 28. You get a buoyant gas (at least on Mars) and oxygen, too. A CO2 atmosphere makes lighter than "air" travel a lot simpler. This sort of thing has also been proposed on Venus, where it would be incredibly effective.

The problem isn't really helped much by the higher density of the atmosphere. The problem is the extreme thinness of it. That means that even a large volume has a very low total mass. It doesn't really matter than one particular gas is buoyant in it- what matters is that the mass displaced by the airship must be greater than the total airship mass. And that's a problem in a near vacuum.

by **Steve Dutch** » Mon Feb 16, 2015 4:35 am

This is a VERY late post. Like a number of people, I doubted that a lighter than air craft could work on Mars, except for one thing. Mars' atmosphere is carbon dioxide, molecular weight 44. That makes it much denser than nitrogen, molecular weight 29. So you could fill the blimp with nitrogen, with enough extra pressure to maintain its shape, and it would still float. I suspect it would be really flabby, but it would still float. In fact, you don't even need to ship air from Earth. Strip off oxygen from the CO2 to make CO, molecular weight 28. You get a buoyant gas (at least on Mars) and oxygen, too. A CO2 atmosphere makes lighter than "air" travel a lot simpler. This sort of thing has also been proposed on Venus, where it would be incredibly effective.

The settlements perched on a long ridge are likely on Iapetus. The yin-yang symbol at bottom center at 1:53 is a clue, and of course Saturn in the far distance.

by **Chris Peterson** » Sat Dec 27, 2014 7:27 pm

BMAONE23 wrote:My best estimation is that it is a Docking Rail for a Habitat that was Tunneled through of the center of the asteroid to create an area where Liquid Water could exist. Part of the internal environment mapping reminded me of Egypt, The Red Sea, and Saudi Arabia

Or maybe a structure supporting what appears to be an artificial sun on the central axis. (Certainly, part of Earth's surface was mapped onto the inside of the cylinder.)

by **BMAONE23** » Sat Dec 27, 2014 7:20 pm

martinharoldjensen wrote:Lovely and enchanting video, but one question: If all scenes represent actual places in the solar system, what is the tunnel of light into which the space craft descends on a rail? I understand that the video shows some imagined dwellings on other planets and moons -- is this supposed to be part of one of those?

I believe you are referring to the scene beginning at 2:06. There is a convoy of 4 ships traveling to an asteroid/minor planet towards a lighted settlement. Next scene is the view from the lead craft heading toward the asteroid. I believe this is followed by the tunnel you are speaking of.
My best estimation is that it is a Docking Rail for a Habitat that was Tunneled through of the center of the asteroid to create an area where Liquid Water could exist. Part of the internal environment mapping reminded me of Egypt, The Red Sea, and Saudi Arabia

It would actually be a fairly ingenious method of creating a "1G" artificial gravity environment in an asteroid of almost any size.
Bore a hole through the center of mass
Cap both ends with Air Locks large enough for ships to enter
Spin the asteroid relative to the central axis of the bore hole
fill with atmosphere and add water.

Might be tough to land on the outside though if the centrifugal force wants to through you away from the surface. (which also might require some strengthening)

by **Chris Peterson** » Sat Dec 27, 2014 6:14 pm

martinharoldjensen wrote:Lovely and enchanting video, but one question: If all scenes represent actual places in the solar system, what is the tunnel of light into which the space craft descends on a rail? I understand that the video shows some imagined dwellings on other planets and moons -- is this supposed to be part of one of those?

All I see is a settlement at the base of the elevator, lit up because it's in night.

by **martinharoldjensen** » Sat Dec 27, 2014 6:06 pm

Lovely and enchanting video, but one question: If all scenes represent actual places in the solar system, what is the tunnel of light into which the space craft descends on a rail? I understand that the video shows some imagined dwellings on other planets and moons -- is this supposed to be part of one of those?

by **geckzilla** » Fri Dec 12, 2014 10:30 pm

Well said, Rob and Chris. I feel sorry for anyone who has never seen beyond the tip of an iceberg, where profound wonder waits in the deep for anyone willing to explore it.

by **Chris Peterson** » Fri Dec 12, 2014 3:27 pm

rstevenson wrote:
les7 wrote:wonderful video.... for those debating the physics of it, just try enjoying the wonder of the cosmos and mankind within it.
For many of us, thinking about the physics and making the effort to understand it, is very much a part of the wonder.

Personally, the wonder of nature is greatly diminished for me when I do not understand some aspect of it. The source of wonder isn't the cosmos itself, but having some sense of how the cosmos works.

by **rstevenson** » Fri Dec 12, 2014 12:40 pm

les7 wrote:wonderful video.... for those debating the physics of it, just try enjoying the wonder of the cosmos and mankind within it.

For many of us, thinking about the physics and making the effort to understand it, is very much a part of the wonder.

Rob

by **les7** » Fri Dec 12, 2014 1:51 am

wonderful video.... for those debating the physics of it, just try enjoying the wonder of the cosmos and mankind within it.

by **Nitpicker** » Fri Dec 12, 2014 12:28 am

Do'h, I see what you mean now, re the ambiguity. My mind didn't think of "recreations" as a relaxing pastime at all in this context, but of creating something based on something else. (A place is not a pastime.)

by **Ron-Astro Pharmacist** » Fri Dec 12, 2014 12:19 am

Nitpicker wrote:
Ron-Astro Pharmacist wrote: I wonder if the lack of a hyphenated "recreations" was intentional?
Hyphenating words like "re-creation" is going out of fashion is some English speaking circles. As such "recreation" is sometimes preferred. I don't think it makes a difference apart from style. What did you mean?

The astronauts depicted in the film appeared by be enjoying their "recreation" in the various settings. In re-watching the video I noticed the disclaimer stating the obvious "..re-creation of the actual places.." and it seemed (close to) a humorous double entendre. The film presented tremendous insight into a possible future and was highly enjoyable. The comment was only meant to point out a possible, intended or unintended, bit of foreshadowing by its talented creator.

by **Nitpicker** » Thu Dec 11, 2014 10:59 pm

Ron-Astro Pharmacist wrote: I wonder if the lack of a hyphenated "recreations" was intentional?

Hyphenating words like "re-creation" is going out of fashion is some English speaking circles. As such "recreation" is sometimes preferred. I don't think it makes a difference apart from style. What did you mean?

by **Ron-Astro Pharmacist** » Thu Dec 11, 2014 6:51 pm

In the film's disclaimer "All locations depicted in this short film are recreations of actual places in our solar system"

recreation (ˌrɛkrɪˈeɪʃən)
n
1. refreshment of health or spirits by relaxation and enjoyment
2. an activity or pastime that promotes this
3. (Education)
a. an interval of free time between school lessons
b. (as modifier): recreation period.

I wonder if the lack of a hyphenated "recreations" was intentional?

by **Chris Peterson** » Wed Dec 10, 2014 11:09 pm

geckzilla wrote:It's likely that trends in makeup will change radically by the time ordinary people are in space.

Kim Stanley Robinson's book 2312 envisions a future when we're spread all over the Solar System, not unlike much of what this video portrays. We're far beyond simply makeup in this future, making radical elective changes to our bodies and gender (there are maybe a dozen gender choices), multiple times over lifetimes that extend to a couple hundred years.

by **BMAONE23** » Wed Dec 10, 2014 10:15 pm

Could be replaced by facial tattooing also

by **geckzilla** » Wed Dec 10, 2014 8:25 pm

Chris Peterson wrote:
geckzilla wrote:I was amused that the spacesuit/fur parka girl at the end took the time to put on some makeup. Priorities!
Hey, people are people. If ordinary people (as opposed to just researchers and adrenaline junkies) are in space, they'll bring all their culture, which includes makeup.

It's likely that trends in makeup will change radically by the time ordinary people are in space. If your face is hard to see through a mask or because of environmental lighting, then it might be appropriate for the makeup to become more extreme in order to emphasize what details do make it through. It might even have some kind of utility to facilitate nonverbal communication but that is probably pushing it. Also, men and women might both commonly wear makeup at that point. Or it might fade out completely. Who knows!

by **Chris Peterson** » Wed Dec 10, 2014 2:58 pm

GJvL wrote:Movie does not show in Chrome...

Yes it does, with Win 7, Win 8, OS X Mavericks, Android 4, Android 5. No plugins required in any of these cases.

Whatever problem you're having, it's not Chrome itself. Something about your system.

by **Chris Peterson** » Wed Dec 10, 2014 2:55 pm

geckzilla wrote:I was amused that the spacesuit/fur parka girl at the end took the time to put on some makeup. Priorities!

Hey, people are people. If ordinary people (as opposed to just researchers and adrenaline junkies) are in space, they'll bring all their culture, which includes makeup.

I'm curious where she is. It's unlikely she's wearing a spacesuit- who would put a parka on the outside? There's an atmosphere. It looks like she's using some kind of rebreather or filter device. Probably not pressurized. It's cold, but not extremely so. Someplace with a fairly thick atmosphere, but not enough oxygen, maybe?

by **GJvL** » Wed Dec 10, 2014 9:50 am

Movie does not show in Chrome...

by **geckzilla** » Wed Dec 10, 2014 9:12 am

I was amused that the spacesuit/fur parka girl at the end took the time to put on some makeup. Priorities!

by **Steve Dutch** » Wed Dec 10, 2014 4:46 am

Wonderful video. I presume the five bright stars in the beginning are the visible planets. It's not terribly uncommon to have all five visible at once - once a decade or so. When Jupiter and Saturn get close, they stay close for several years. It's inevitable that the others will get close too at some point.

I'm not totally sure lighter than air craft will work where atmospheric pressure is 1% of Earth's, like in the Mars scene.

The human powered flight on Titan is breathtaking. With a denser atmosphere than Earth, and lower gravity, it might be possible. Maybe the flight units are powered, too.

I hope the jumpers on Miranda have braking jets. Even with that low gravity, and a 15-km fall that would take minutes, it would probably kill you.

The girl at the end is wearing a fur parka and a respirator because all the gas giants have a temperature and pressure zone that's survivable by humans. So she's probably on a floating station like the one in the distance. She doesn't need a spacesuit. She might not even need the parka, but that would probably have challenged viewer suspension of disbelief a bit much.

I love it.

by **rstevenson** » Wed Dec 10, 2014 2:38 am

BMAONE23 wrote:Crazy of another sort...

I actually saw something like this -- very definitely not deliberate -- at a sky-diving demonstration back in the 70s here in Halifax. Four skydivers, intending a display of aerial prowess, had dropped over the Commons. The main chute of one of them popped out but failed to fully open. The hundreds of watchers below, including my wife and I, could only stare up in horror as he came down. He maintained a slow spiral motion, flat, with arms and legs wide spread, and managed to hold that posture until he hit, just about 100' feet west of the commons boundary. He was lucky: he hit the 45° slope of a house roof, and bounced off it, coming to rest with his elbows and knees buried in the relatively soft cinder driveway of the house. He broke all sorts of bones, but survived to tell the tale. His compatriots said he did what he could by maintaining that posture, and was lucky that his chute dragging behind helped in keeping his terminal velocity to about 95 mph. Any faster, they said, and he wouldn't have had even a slim chance of survival. He flew and jumped again about a year later!

Rob

by **JohnD** » Tue Dec 09, 2014 11:18 pm

Mike biochemiker,
The equations I gave in my earlier post:

Time to fall (t) = SQRT(2 x distance/g)
Velocity (v) at end of fall= g x t
Distance (d) fallen = (g x t^2)/2

I'm sure you can work out your example - mine gave me an entertaining five minutes., which I'm glad to repeat.

1/ Time to fall 5km = SQRT(2 x 5000/g) = 354s
Velocity at end of fall = 0.08 x 354 = 28m/s (63mph)

2/ and so on

John

by **BMAONE23** » Tue Dec 09, 2014 10:36 pm

Crazy of another sort

Click to play embedded YouTube video.

Starship Asterisk*

APOD: Wanderers (2014 Dec 08)

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