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#1 2004-03-01 09:08:00

Ian
Member
Registered: 2002-01-08
Posts: 236

Re: solar sail - solar sail

Does anyone think that the launching of the solar sail that Cosmos Studios is building will actually be sucessful because last time there was a problem and it fell back to earth. They said that sometime this year it'll be launched again. Here's the website for it http://www.solarsail.org

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#2 2004-03-01 09:17:15

Rxke
Member
From: Belgium
Registered: 2003-11-03
Posts: 3,658

Re: solar sail - solar sail

the failure, IIRC, had nothing to do with the sail itself, it was the launcher separation that was the cause...

BTW: this sail will probably fall back, too... After a while. (If they didn't change their plans for a bigger one...)

It is just meant as a testbed, to see how much 'power' this thing has. But it probably won't be able to leave Earth-orbit...

Probably... You never know, though!


ExoMars' launcher's 2nd stage is probably en route to Mars. Unsterilised... yikes

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#3 2004-03-01 11:55:14

Ian
Member
Registered: 2002-01-08
Posts: 236

Re: solar sail - solar sail

It probabaly won't fall back to the earth this time. They spent months trying to figure out what went wrong and they'll probably try to correct their mistakes. I hope that thing eventually enters into orbit around the earth.

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#4 2004-03-01 13:06:11

Rxke
Member
From: Belgium
Registered: 2003-11-03
Posts: 3,658

Re: solar sail - solar sail

I'm fairly confident, too. They know what went wrong, as you said, won't happen again. Of course, deployment of the sail is still experimental...

Let's hope there are no mayor solar flares occurring during the operation, when that happens, Earth's atmosphere expands, so drag would increase...

And again, a private company bites the bullet, fed-up with the sluggishness of big Government operations in space. Awesome. :up:

I hope that thing eventually enters into orbit around the earth

I hope it *leaves* Earth orbit!


ExoMars' launcher's 2nd stage is probably en route to Mars. Unsterilised... yikes

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#5 2004-03-01 13:41:51

Ian
Member
Registered: 2002-01-08
Posts: 236

Re: solar sail - solar sail

I also hope that it'll eventually take us beyond low earth orbit and to the planets and then to the stars.

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#6 2004-03-01 20:41:58

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: solar sail - solar sail

A neat idea, and will probably work for long-range probes, but the problem is that is simply doesn't produce much thrust and they are hard to navigate... two things manned flight requires.


"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw

The glass is at 50% of capacity

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#7 2004-03-02 02:43:51

Josh Cryer
Administrator
Registered: 2001-09-29
Posts: 3,830

Re: solar sail - solar sail

Lots of manuverablity for a large ship is inefficient anyway. smile

Solar sails scale up pretty well depending on the materials used. A several molecule thick sheet of nanocarbon sail would be ridiciulously light. Let's not forget the dusty plasma sails.

I wouldn't rule out solar sails just yet, since they require far less fuel than other types of vehicles, and the fuel (for dusty plasma sails) they do require is quite easy to obtain.


Some useful links while MER are active. Offical site NASA TV JPL MER2004 Text feed
--------
The amount of solar radiation reaching the surface of the earth totals some 3.9 million exajoules a year.

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#8 2004-11-09 06:55:21

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 17,814

Re: solar sail - solar sail

Devising a Way to 'Sail' to Mars
While this may seem a little far fetched it however would be a possibility for cargo. Article mentions cosmos 1.

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#9 2004-11-10 06:42:20

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 17,814

Re: solar sail - solar sail

Cosmos 1 is closing in on that magical date to show that a sail can be pushed by photons, costing under 4 million. So how cheap is that russian sub rocket?

Planetary Society’s Cosmos 1 Solar Sail Ready for Flight

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#10 2004-11-24 14:37:28

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 17,814

Re: solar sail - solar sail

Update on launch date, set for Cosmos 1 solar sail mission for launch starting on March 1, 2005. The launch window will be open from that date through April 7 at the determination of the Russian Navy, for it is they who will send this unique satellite into Earth orbit atop a Volna rocket from a submarine in the Barents Sea near the Arctic Circle.

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#11 2005-02-14 05:37:19

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 17,814

Re: solar sail - solar sail

Ambitious solar sail could launch this spring

Officials reported last week that the launch will have to be delayed from earlier targets in March, but project director Louis Friedman said there is currently nothing standing in the way of a launch some time in April.

"We now project that Cosmos 1 will launch in April. The testing on the flight spacecraft, but some corrections and fixes have been required," Friedman reported in an update on the Planetary Society website.

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#12 2005-02-14 10:06:13

John Creighton
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From: Nova Scotia, Canada
Registered: 2001-09-04
Posts: 2,401
Website

Re: solar sail - solar sail

What happens if a sail gets a hole? I am sure if you have a sail the size of a football field there is a good chance of it getting struck by a meteorite.

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#13 2005-02-14 15:31:53

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: solar sail - solar sail

Well, that would change your thrust vector slightly and reduce overall thrust. However, unless large sections of the sail were lost, this isn't likly to be much of a problem.


"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw

The glass is at 50% of capacity

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#14 2005-02-14 17:32:35

flashgordon
Member
Registered: 2003-01-21
Posts: 314

Re: solar sail - solar sail

i thougth the japanese have already successfually launched a solar sail for 'unfolding' demonstration purposes?!

In other words, why are they not sending probes all over the solar system right now?

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#15 2005-02-14 18:20:46

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: solar sail - solar sail

The first big issue is cost, that getting money to build any probe or satelite that costs more then $100M is not that easy. NASA needs most every penny its got at the moment.

Second, the solar sail doesn't work very well without gobs of sunlight, but the Sun is pretty dim even at Mars orbit, and is all but pitch black out at Saturn or further.

Third, the sail has such low thrust, that it takes a very long time to get anywhere. There is a risk that the probe will be getting pretty old by the time it arrives, plus the cost of operating it for all those years and the expense of making it surviveable that long add up. In such a case, plain old chemical engines or chemical+ion can be more attractive.

And lastly, nobody has demonstrated the manufacture or deployment of a sail of the required size.


"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw

The glass is at 50% of capacity

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#16 2005-02-18 23:03:38

Mad Grad Student
Member
From: Phoenix, Arizona, North Americ
Registered: 2003-11-09
Posts: 498
Website

Re: solar sail - solar sail

The great thing about solar sailing is that it is the only advanced propulsion system that can be developed with absolutely no (or very little) new technology and is politically-acceptible (unlike, say, Orion). With super-thin carbon sails you could probably get at least somewhat better acceleration than you could through ion engines, without the need for a big nuclear reactor, and essentially limitless propulsion in the inner solar system. Other future propulsion systems like fusion or GCNRs would be preferable, but those would entail much more time and cost to develop. IMHO fusion will eventually become the standard for all interplanetary travel (assuming of course that that becomes commonplace), but right now fusion technology is too immature to produce break-even power, let alone a spacecraft propulsion system. Given enough funding and a decade or two in development, though, and fusion will open amazing possibilites for space travel in general.

However, for now solar sailing looks to have a great deal of promise. If we can solve the issues of developing, packing, and deploying very thin slices of aluminum and carbon, an increadibly promising drive system awaits. Compared to the difficulties of developing other new propulsion systems, these issues are relatively minor. Hopefully NASA will be able to some money left over to pay for future sail research. Heck, it should fit right in the VSE; perhaps Prometheus should be expanded to include development of new interplanetary drive systems rather than only nuclear-ion power.


A mind is like a parachute- it works best when open.

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#17 2005-02-18 23:50:30

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: solar sail - solar sail

No, no I don't think so. Earnestly looking into solar sails is the wrong thing to do right now.

First of all, solar sails are NOT an "advanced propulsion system" with respect to getting you anywhere quickly, that is due to the extremely low thrust and navigational limitations using a sail will dictate long travel times no matter what. Solar sails are good for when you want to save on propellant, but lousy if you need to get anywhere in a timely fasion. A long solar sail trip might even take so much time that the payload & bus may get too old.

Second, you have waved a magic wand to conjur up this hypothetical ultrathin carbon composit substrate for the solar sail mirror, which does not exsist.

Then there is the cost and expense of the fabrication of a mirror large enough to be very useful is also a question mark, and could prove to be very difficult and expensive... spraying vaporized aluminum metal onto an organic composit substrate would definatly be an expensive process. These are not minor or trivial issues as you so casually brush aside, and may prove to be a genuine show-stopper.

"...it should fit right in the VSE; perhaps Prometheus should be expanded to include development of new interplanetary drive systems rather than only nuclear-ion power."

Absolutely positively not, Prometheus is under-funded enough as it is, and we must have a reactor for extended Lunar stays or any Mars mission, the ion engines are really mostly an excuse to build the reactor.

Nor does a solar sail "fit right in" with VSE, due to its painfully, agonizingly slow travel times. Perhaps even too long for unmanned space probes depending on details.

Prometheus is a very targeted, vital cog in the machine of VSE, it must not be tamperd with or diluted any more then nessesarry, and definatly not because of any enviro-political "yay solar energy for NASA too! now they won't need nukes!" business.


"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw

The glass is at 50% of capacity

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#18 2005-02-21 12:29:04

deagleninja
Member
From: USA
Registered: 2004-04-28
Posts: 376

Re: solar sail - solar sail

Hey GCNR, saw a great article on a few sites about solar sails. Apparently, there is a way to boost their efficency with a spray on adhesive that acts like propellent when targeted with microwaves. Here's the link, its pretty cool...

http://www.space.com/busines....11.html

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#19 2005-02-21 12:31:50

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: solar sail - solar sail

Saw it already, very skeptical. Anybody who says "Mars in a month!" without some idea of payloads isn't credible in my opinion.


"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw

The glass is at 50% of capacity

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#20 2005-02-21 12:43:52

deagleninja
Member
From: USA
Registered: 2004-04-28
Posts: 376

Re: solar sail - solar sail

Yeah, I'm skeptical about that line too. I don't think he is assuming any payload or at best a very small science package. Certainly not tons of equipment needed to start a Martian outpost.

I am rather excited about the possibilities however. Instead of solar sails hundreds or thousands of miles to a side, we may be looking at much more efficent sails in the 'football feild' range. Perhaps it wouldn't be too hard to have robotic travel the area of a solar and re-apply a compound to maintain a nice velocity?

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#21 2005-02-21 13:02:05

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: solar sail - solar sail

If you vastly increase the mass of the sail, the pressure on the sail, and so on though, you also have to make the sail itself far heavier.

The microwave beam generator is a big hurdle too I think, that you would need several many megawatt beams dotted around the globe to maintain a nice push continuously. $$$

A robot that would resist being blasted by a huge amount of microwave energy? Mmmm don't know about that.

Its a neat idea, but like most other "clever" propulsion schemes, makes more sense as a ploy to keep dreamer engineers employed then a practical propulsion system.


"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw

The glass is at 50% of capacity

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#22 2005-05-02 05:47:30

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 17,814

Re: solar sail - solar sail

Ohio Lab Tests Space Propulsion System

Scientists working with a synthetic material 100-times thinner than a piece of paper are testing their theory that the sun can power interplanetary spacecraft. They believe that streams of solar energy particles called photons can push a giant, reflecting sail through space the way wind pushes sailboats across water.

Small investment so far by Nasa:

The National Aeronautics and Space Administration has invested about $30 million in space-sail technology, something that existed solely in science-fiction novels a decade ago.

And the testing is being done here:

The Space Systems division developed the solar sail, which is being tested in the world's largest vacuum chamber at the Cleveland-based     NASA Glenn Research Center's Plum Brook Station in Sandusky. It has a space environment simulation chamber 100 feet in diameter and 122 feet high.

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#23 2005-06-20 00:19:46

Yang Liwei Rocket
Member
Registered: 2004-03-03
Posts: 993

Re: solar sail - solar sail


'first steps are not for cheap, think about it...
did China build a great Wall in a day ?' ( Y L R newmars forum member )

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#24 2005-06-20 14:28:42

C M Edwards
Member
From: Lake Charles LA USA
Registered: 2002-04-29
Posts: 1,011

Re: solar sail - solar sail

They launch tomorrow!  How exciting.   cool


"We go big, or we don't go."  - GCNRevenger

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#25 2005-06-21 01:03:41

Euler
Member
From: Corvallis, OR
Registered: 2003-02-06
Posts: 922

Re: solar sail - solar sail

Solar sails are good for some things, but they don't really scale up very well, so they are not a good choice for human missions.  They also cannot perform their best on missions to the Moon or Mars, so Solar Sails are not a very VSE friendly method of propulsion.

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