NASA to test new solar sail technology

October 14, 2011 By Ray Sanders, Universe Today

NASA to test new solar sail technology

Enlarge

The Solar Sail demonstration mission. Credit: NASA

Solar sails, much like anti-matter and ion engines appear at first glance to only exist in science fiction. Many technologies from science fiction however, become science fact.

In the example of solar sails, perfecting the technology would allow to travel through our solar system using very little fuel.

NASA has been making strides with solar sail technology. Using the NanoSail-D mission, NASA continues to gather valuable data on how well solar sails perform in space. The Planetary Society will also be testing solar sail technology with their LightSail-1 project sometime next year.

How will NASA (and others) test solar sail technology, and develop it into a common, reliable technology?

The second of three recently announced technology demonstrations, The Solar Sail Demonstration, will test the deployment of a solar sail in space along with testing . The solar sail will also execute a navigation sequence with mission-capable accuracy.

In order to make science fiction into reality, NASA engineers are testing solar sails that could one day provide the propulsion for deep . Spacecraft using solar sails would travel in our solar system in a similar manner to a sailboat through water, except spacecraft using solar sails would rely on sunlight instead of wind. A spacecraft propelled by a solar sail would use the sail to capture photons emitted from the Sun. Over time, the buildup of the solar photons provides enough thrust for a small spacecraft to travel in space.

NASA’s solar sail demonstration mission will deploy and operate a sail area 7 times larger than ever flown in space. The technology used in the demonstration will be applicable to many future space missions, including use in space weather warning systems to provide timely and accurate warnings of solar flare activity. The solar sail demonstration is a collaborative effort between The National Oceanic and Atmospheric Administration (NOAA), NASA and contractor L’Garde Inc.

NASA to test new solar sail technology
Enlarge

A solar sail system, measuring 66 feet on each side was tested in 2005 in the world's largest vacuum chamber. Image Credit: NASA

lists several capabilities solar sails have to offer, such as:

-- Orbital Debris: Orbital debris can be captured and removed from orbit over a period of years using the small solar-sail thrust.

-- De-orbit of spent satellites: Solar sails can be integrated into satellite payloads so that the satellite can be de-orbited at the end of its mission.

-- Station keeping: Using the low propellantless thrust of a solar sail to provide station keeping for unstable in-space locations.

-- propulsion: Payloads free of the Earth’s pull can be continuously and efficiently accelerated to the other planets, or out of the solar system, such as proposed in Project Encounter.

As an example, the GeoStorm project considers locating solar storm warning satellites at pseudo Lagrange points three times further from the Earth by using the to cancel some solar gravitational pull, thus increasing warning time from ~15 minutes to ~45 minutes.

Providing a satellite with a persistent view of northern or southern latitudes, i.e., a “pole-sitter” project. This allows the observational advantages of today’s geosynchronous satellites for orbits with view angles of the northern and southern high-latitudes.

More information: If you’d like to learn more about solar sails, Caltech has a nice “Solar Sailing 101″ page at: http://www.ugcs.ca … o/intro.html

Source: Universe Today

4.9 /5 (8 votes)  

Filter


Move the slider to adjust rank threshold, so that you can hide some of the comments.


Display comments: newest first

dschlink
Oct 14, 2011

Rank: 5 / 5 (4)
When will the USA or even NASA join the rest of the world in using metric? Isn't losing one multi-million dollar mission enough?
El_Nose
Oct 14, 2011

Rank: 3.7 / 5 (3)

NASA does use metric they are scientists ;-) but if you are going to write an article or relate it to people in this country youuse converted units
Nanobanano
Oct 15, 2011

Rank: 1 / 5 (4)
This type of solar sail is very, very weak compared to the electronic solar sail.

The website the article links to derives a mere 9 Newtons of thrust per square kilometer of sail.

I find that our deep space probes have mass anywhere from 1500kg to 12,000kg.

It's incredibly efficient, but also incredibly, incredibly slow.

So doing a slightly simplified linear average of solar constant between 1 and 4 A.U., I find the average thrust along that track is around 1.44 Newtons, because solar constant changes with distance, again, a rough approximation. It's actually requires a bit more calculation I'm not awake to do yet. If you're sending a 10,000kg probe (counting mass of the sail) using a 1 square km sail, on a trip to the outer solar system.

The "average" acceleration along the track amounts to 1.44n/10,000kg, which comes to 0.5184 m/s/HOUR.

The initial acceleration is ~9n/10,000KG, which comes to 3.24m/s/HOUR.

It turns out, this doesnt even overcome the Sun's gravity
Nanobanano
Oct 15, 2011

Rank: 1 / 5 (4)
So your solar sail obviously needs to already be moving at Solar Escape Velocity (with respect to it's starting distance from the Sun,) and then the thrust serves to further accelerate the sail. No biggy.

Using a probe of 2000kg, (1500 for the probe itself, and then maybe the sail being 1km squared is probably at least 500kg...): I.e. similar to Yovager, wherease 10,000 would be similar to Cassini.

You'd get 1.44n/2,000kg, which is 2.592m/s/Hour average between 1 and 4 a.u.

You'd get 9n/2,000kg, or 16.2m/s/hour (Even this is only about 80% enough to overcome the Sun's gravity at 1a.u., so you still need to already be moving at solar escape velocity).

but the cool thing about this is the energy efficiency and EPIC maximum velocities it can achieve.

I just estimated the 2,000kg sized probe with 1km^2 sail should be able to reach 4a.u. (1 plus 3,) in under 420 days flight time, having at that time, velocity near 26km/s, which makes rockets and ion engines look pathetic.
Nanobanano
Oct 15, 2011

Rank: 1 / 5 (4)
to compute the time and velocity more precisely it takes a bit of work,

I think it involves definite integral 9/(x^2), from 1au to 4au, which antiderivative is -9/x.

If you computer that for 1a.u and 4a.u. in meters, and subtract 1 from 4, in meters, then divide by mass, you should get the reciprocal of time squared.

But when I did that, I got 78 days travel time from 1.au. to 4a.u., which is a ridiculously small time compared to my prior attempt at a linear approximation. Admittedly, linear approximations actually suck for this sort of thing, but 78 days to 4a.u. sounds a bit.

Def. integral (9/x^2) from A to B.

A is 153,000,000,000m
B is 4A.

this gives a number in units of kg/s^2.

Divide that result by 2000kg, giving units 1/s^2.
Take the reciprocal, giving s^2
Take the square root, giving time.

Convert to days.

78 days.

Seems insane if that's true...God the linear is useless.
Nanobanano
Oct 15, 2011

Rank: 1 / 5 (3)
Ah yeah, 78 days is definitely wrong. It's the 9 newtons is a self-referencial term, and should also be in "newtons per kilometer square," which is obfuscated.

I gotta figure out a way to set up the formula to take this into account.

As it's set up the outputs are not realistic, as you reach 2 a.u. before 4a.u. which is ridiculous. I thought something was wrong with this, but I had to catch myself. I post fix shortly.
Nanobanano
Oct 15, 2011

Rank: 1 / 5 (3)
hmmm should stick to first intuition...

TheGhostofOtto1923
Oct 15, 2011

Rank: 5 / 5 (2)
Yo sickboy
How long before somebody comes along and shows you how obviously wrong you are here also?

I have an idea. In order to begin addressing this compulsive mania of yours, I suggest you admit your errors when they are pointed out by others, admit that your personal knowledge and experience was thus inadequate to attempt what you were attempting, and apologize for your effrontery.

The first step to recovery is admitting you have a problem. I suggest you go back to the last thread where you attempted to explain galaxies and black holes, OWN UP to your deficits in light of informed criticism, and APOLOGIZE for what you did.

Can you do this?
El_Nose
Oct 24, 2011

Rank: not rated yet
@NANBANANO ==== where do you get your info???

LightSail-1 is a three-unit Cubesat, which weighs 4.5 kg and measures only 10x10x30 cm.

This satellite is not meant to leave Earth orbit -- let alone the solar system!!

Lightsail -2 is not meant to leave Earth orbit

Lightsail-3 -- might leave Earth orbit -- might!!!
Rank 4.9 /5 (8 votes)
Relevant PhysicsForums posts
  • Distance of planets from stars and revolution
    created1 hour ago
  • revamping general concept and cosmological principle
    createdMay 25, 2012
  • Transiting Exoplanet Light Curve
    createdMay 25, 2012
  • Math behind Theoretical Physics
    createdMay 24, 2012
  • Do we know whats at the center of galaxies yet?
    createdMay 23, 2012
  • Structure of the Milky Way?
    createdMay 20, 2012
  • More from Physics Forums - General Astronomy

More news stories

Yale study concludes public apathy over climate change unrelated to science literacy

Are members of the public divided about climate change because they don't understand the science behind it? If Americans knew more basic science and were more proficient in technical reasoning, would public consensus match ...

Space & Earth / Environment

created 1 hour ago | popularity not rated yet | comments 8 | with audio podcast

10 million years needed to recover from mass extinction

It took some 10 million years for Earth to recover from the greatest mass extinction of all time, latest research has revealed.

Space & Earth / Earth Sciences

created 1 hour ago | popularity not rated yet | comments 1 | with audio podcast

Sophisticated simulations predict future warming

The chances of our planet being hit by a global warming of 3 degrees Celsius by 2050 is as likely as it being hit by an increase of 1.4 degrees, new research shows. Presented in the journal Nature Geoscience, the British study ...

Space & Earth / Earth Sciences

created May 22, 2012 | popularity 4.4 / 5 (9) | comments 51

Aliens don't want to eat us, says former SETI director

Alien life probably isn’t interested in having us for dinner, enslaving us or laying eggs in our bellies, according to a recent statement by former SETI director Jill Tarter.

Space & Earth / Space Exploration

created May 25, 2012 | popularity 4.4 / 5 (14) | comments 39

Kyoto Protocol architect 'frustrated' by climate dialogue

UN climate talks are going nowhere, as politicians dither or bicker while the pace of warming dangerously speeds up, one of the architects of the Kyoto Protocol told AFP.

Space & Earth / Environment

created May 23, 2012 | popularity 3.7 / 5 (7) | comments 39


'Unzipped' carbon nanotubes could help energize fuel cells, batteries

Multi-walled carbon nanotubes riddled with defects and impurities on the outside could replace some of the expensive platinum catalysts used in fuel cells and metal-air batteries, according to scientists at ...

T cells 'hunt' parasites like animal predators seek prey, study shows

By pairing an intimate knowledge of immune-system function with a deep understanding of statistical physics, a cross-disciplinary team at the University of Pennsylvania has arrived at a surprising finding: T cells use a movement ...

Computer model used to pinpoint prime materials for efficient carbon capture

When power plants begin capturing their carbon emissions to reduce greenhouse gases – and to most in the electric power industry, it's a question of when, not if – it will be an expensive undertaking.

Change in developmental timing was crucial in the evolutionary shift from dinosaurs to birds: study

At first glance, it's hard to see how a common house sparrow and a Tyrannosaurus Rex might have anything in common. After all, one is a bird that weighs less than an ounce, and the other is a dinosaur that ...

Same gene that stunts infants' growth also makes them grow too big: research

UCLA geneticists have identified the mutation responsible for IMAGe* syndrome, a rare disorder that stunts infants' growth. The twist? The mutation occurs on the same gene that causes Beckwith-Wiedemann syndrome, which makes ...

Scientists develop ultra-sensitive test that detects diseases in their earliest stages

Scientists have developed an ultra-sensitive test that should enable them to detect signs of a disease in its earliest stages, in research published today in the journal Nature Materials.