[FPSPACE] FW: Centauri Dreams - NanoSail-D: Solar Sail Deployment Planned

[LARRY KLAES]

>From: Centauri Dreams <gilster at mindspring.com>
>Reply-To: Centauri Dreams <gilster at mindspring.com>
>Subject: Centauri Dreams
>Date: Tue, 1 Jul 2008 14:02:47 -0500 (CDT)
>
>Centauri Dreams
>
>///////////////////////////////////////////

>NanoSail-D: Solar Sail Deployment Planned
>
>Posted: 01 Jul 2008 08:10 AM CDT

>http://www.centauri-dreams.org/?p=1952
>
>
>Solar sail development has surely been a frustrating thing for Sandy 
>Montgomery, who knows that what stands in the way of pushing this 
>technology into space isnt the need for scientific breakthroughs but 
>adequate funding. Montgomerys team at Marshall Space Flight Center has been 
>examining the potential of solar sails for a long time, and is well aware 
>that leaving the propellant behind is a way to get more payload to your 
>destination with considerably less overhead all around.
>
>
>
>And solar sails, which can ride the momentum imparted by photons from the 
>Sun, are the ideal way to study propellantless propulsion with near-term 
>technologies. What a pleasure to see the launch window approaching for a 
>solar sail deployment experiment in space, led by Montgomerys team and 
>counterparts at NASA Ames. NanoSail-D is to be launched aboard a Space 
>Exploration Technologies (SpaceX) Falcon rocket some time at the end of 
>July or the beginning of August. Montgomery calls it the first fully 
>deployed solar sail in space, and the first spacecraft to use solar 
>pressure as a primary means of attitude control or orbital maneuvering.
>
>Image: NanoSail-D is made of extremely lightweight gossamer fabric designed 
>to glide into space. Image Credit: NASA/MSFC/D. Higginbotham.
>
>Its also an opportunistic way to reach low-Earth orbit, since NASA Ames was 
>already committed to participation in the Falcon 1 launch, and the Poly 
>Picosatellite Orbital Deployer (P-POD) developed at California Polytechnic 
>State University is ready to deploy the sail. Nano may be an overstatement, 
>but it does capture the small size of this missions payload, which weighs 
>in at a scant nine pounds and measures only slightly larger than a loaf of 
>bread in length.
>
>Compared to some of the huge designs contemplated for future missions, the 
>sail itself is relatively small. Weighing less than ten pounds (Montgomery 
>notes that the team carries it around in a special suitcase), the sail will 
>deploy to about 100 square feet of surface. This video  offers a helpful 
>explanation of the deployment of the sails panels.
>
>A realistic technology for future missions? Believe it. Although the push 
>from the Sun is tiny, the effects are cumulative and quickly begin to 
>mount. Says Montgomery:
>
>Its not so much about how far a sail will go compared to a rocket; the key 
>is how fast. The Voyagers have escaped the solar system, and they were sent 
>by rockets, but its taken more than three decades to do it. A sail launched 
>today would probably catch up with them in a single decade. Sails are 
>slower to get started though. So, for example, between the Earth and the 
>moon, rockets might be preferred for missions with a short timeline. Its a 
>trip of days for rockets, but months for a solar sail. The rule of thumb, 
>therefore, would be to use rockets for short hops and solar sails for the 
>long hauls.
>
>Think, too, about how the idea of solar sails is changing. The vast sails 
>described by Cordwainer Smith (The Lady Who Sailed the Soul) or Arthur C. 
>Clarke (The Wind from the Sun) were envisioned without a functioning 
>nanotechnology to support them. Montgomery notes that todays 
>microelectronics make it possible to shrink the size of the sail and still 
>perform serious missions. In a few decades, nanotech may have reached the 
>point where smaller sails are sufficient to get assembler-laden research 
>stations to their destinations. As we deploy NanoSail-D, lets keep an eye 
>on developing sail technologies, including beamed microwave propulsion, as 
>we look to future prospects for even longer missions via laser or particle 
>beam methods.
>
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>
>This posting includes a media file: 
>http://science.nasa.gov/headlines/y2008/images/nanosaild/nanosail.wmv
>
>--