On May 20, the Planetary Society will launch a tiny "citizen-funded" satellite that will test the unfolding of a 32 m2 (344 ft2) solar sail. A solar sail uses radiation pressure from the Sun over a large surface area to propel a spacecraft. IKAROS was the first spacecraft to successfully demonstrate the technology in space. While this month's mission is simply a test of the sail deployment, the main mission, LightSail-1, will launch high enough to actually test the sail as a means of propulsion:
LightSail-1's goal is to test if solar sails are a viable form of space transport. The theory will be tested by measuring if there is any increase in LightSail-1's orbital speed once the spacecraft is released at an altitude of 500 miles (800 km). The Planetary Society originally hoped to launch LightSail-1 in 2012, but in 2014 announced that it is scheduled for launch in April 2016.
An initial test launch of the LightSail spacecraft is scheduled for May 2015. This launch will deliver the satellite to an orbit low enough that atmospheric drag exceeds the thrust available from the light sail, but will allow a full checkout of the satellite's systems in advance of the main 2016 mission.
If LightSail-1 is successful, then the Planetary Society will execute two more solar sail projects with more complex goals. LightSail-2's goal will be to collect scientific data and improve solar sailing control. LightSail-3's goal would be to travel to the L1 Lagrangian point. There, it would be used to detect geomagnetic storms on the Sun, which can damage power and communication systems on Earth and orbiting spacecraft. Such detection will provide earlier warnings of potential power failures.
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The NASA Innovative Advanced Concepts (NIAC) program awards researchers $100,000 grants to help them prepare feasibility studies of their space exploration and aerospace ideas. The Phase I selections for 2015 are listed here.
Mason Peck of Cornell University has proposed a "robotic squid" (or eel) that could be used to explore the oceans of Europa. Other proposals include "In-Space Manufacture of Storable Propellants", asteroid mining, and directed energy propulsion. From NASA's press release:
NIAC Phase I awards are valued at approximately $100,000, providing awardees the funding needed to conduct a nine-month initial definition and analysis study of their concepts. If the basic feasibility studies are successful, awardees can apply for Phase II awards, valued up to $500,000 for two additional years of concept development.
One of the selected proposals calls for the use of a soft-robotic rover for missions that can't be accomplished with conventional power systems. This rover would resemble an eel with a short antenna on its back that harvests power from locally changing magnetic fields. The goal is to enable amphibious exploration of gas-giant moons like Europa.
Another proposal will look at using two glider-like unmanned aerial vehicles connected by an ultra-strong cable at different altitudes that sail without propulsion. The vehicle would use wind shear in the lower stratosphere (approximately 60,000 ft.), similar to a kite surfer, where the upper aircraft provides lift and aerodynamic thrust, and the lower aircraft provides an upwind force to keep it from drifting downwind. If successful, this atmospheric satellite could remain in the stratosphere for years, enabling NASA's Earth science missions, monitoring capabilities or aircraft navigation at a fraction of the cost of orbital satellite networks.
Also at Wired and The Register.
Covered at Sen is the news that a software glitch is causing problems for the Light Sail project launched by the Planetary Society
The privately funded Planetary Society, a California-based space exploration advocacy group, has not been in communication with its LightSail since Friday, two days after it hitched a ride to orbit aboard an Atlas 5 rocket carrying the U.S. Air Force’s X-37B robotic mini shuttle.
This is also covered at the Planetary Society blog:
It is now believed that a vulnerability in the software controlling the main avionics board halted spacecraft operations, leaving a reboot as the only remedy to continue the mission. When that occurs, the team will likely initiate a manual sail deployment as soon as possible.
...
The manufacturer of the avionics board corrected this glitch in later software revisions. But alas, LightSail’s software version doesn’t include the update.
The team are hoping for a reboot to bring the device back to life, either from a ground transmission or charged particle glitch, although attempts to reboot from the ground look to have failed to date.
Cal Poly is automating the reboot command transmission to be sent every few ground station passes, on the hope that one command sneaks through (we don't send the command on every pass because a successful reboot triggers a waiting period before beacon transmissions begin). But as of right now, we can’t do much except wait, hoping a charged particle smacks the spacecraft in just the right way to cause a reboot. LightSail is capable of remaining in orbit about six months in its CubeSat form.
Additional background on the project is available in a previous SN article, and ongoing updates at the mission control page for the LightSail project.
[Editor's Comment: Original Submission]
LightSail 2 Sends Back 1st Signals from Its Solar-Surfing Test Flight
The space advocacy organization The Planetary Society recently confirmed that its LightSail 2 spacecraft has sent its first signals home from space.
The roughly 11-lb. (5 kilograms) cubesat is designed to prove that solar sailing is a feasible way of keeping satellites moving. Fuel is a costly and heavy commodity, and if LightSail 2 can prove that the solar-powered technique works well, perhaps future missions into the deep reaches of the solar system and beyond can be propelled by the charged particles released by the sun.
The project launched into space last week (June 25) from the Kennedy Space Center in Florida aboard a SpaceX Falcon Heavy megarocket. On Tuesday (July 2), the bread-loaf-size LightSail 2 experiment left Prox-1, its carrier vehicle. LightSail 2 will ultimately open up its ultrathin four-panel sail to achieve a surface area about the size of a boxing ring.
[...] Once the cubesat deploys its solar sail early next week, the rays from the sun will give LightSail 2 a gentle push. The goal is to observe LightSail 2 over the course of a month to see if it shifts in its orbit by a measurable amount, according to The Planetary Society officials. That will help demonstrate that solar sailing is an effective satellite-propulsion technique.
In other news, 'Oumuamua is not an alien light sail, probably.
See also: What's the Difference between LightSail 1 and LightSail 2?
First Contact! LightSail 2 Phones Home to Mission Control
See the Latest Data from LightSail 2 on Our New Mission Control Dashboard (here)
Previously: Planetary Society's "LightSail" Solar Sail Test Launch on May 20
Lightsail Update: Back in Communication
Planetary Society's LightSail Has Finally Deployed After Multiple Setbacks
One Legacy of Carl Sagan May Take Flight Next Week—a Working Solar Sail
Falcon Heavy to Launch STP-2; 4-Hour Window Opens @ 2019-06-25 2:30am EDT (2019-06-25 0630 UTC)
Drama in Low-Earth Orbit as LightSail 2 Deploys its Sails:
LightSail 2 has successfully deployed its solar sails. Shortly after 12:00 pm PST The Planetary Society tweeted that the sails were deployed, and that the spacecraft was sailing with sunlight. We can all enjoy their success and start to wonder how solar sails will fit into humanity's plans for space exploration.
[...] This is a dramatic moment for LightSail 2 and for The Planetary Society, the world's largest non-profit space organization. LightSail 2 is the third spacecraft in their LightSail program. It was launched on June 25th, and has been in orbit since then, preparing for sail deployment and sending us some sweet pictures of Earth.
[...] LightSail 2's sail is actually a system of four smaller triangular sails that make one large square when deployed. Once deployed, the sail measures 32 sq. meters, or 340 sq. ft. Once it's deployed, it can be used to raise the spacecraft's orbit, demonstrating the power and usefulness of solar sails.
[...] In some ways, the solar sail is exactly like a sail on a boat. The sail can be aimed at angles, to direct the travel of the spacecraft. If the sails are aimed directly at the Sun, the spacecraft will travel directly away from the Sun. But by tacking, or changing the angle of the sails, a spacecraft using solar sails can steer and propel itself through the Solar System and beyond.
Planetary Society Twitter feed.
Also at: The Register, NYT, and The Verge.
Previously:
Planetary Society Receiving Data From LightSail 2
One Legacy of Carl Sagan May Take Flight Next Week—a Working Solar Sail
Planetary Society's "LightSail" Solar Sail Test Launch on May 20
(Score: -1, Flamebait) by Anonymous Coward on Sunday May 10 2015, @06:32AM
Hippie solar cannot be allowed to succeed. SHOOT IT DOWN.
(Score: 0, Disagree) by Anonymous Coward on Sunday May 10 2015, @07:03AM
32 square meters and 32 meters squared are not the same thing.
-- gewg_
(Score: 3, Interesting) by takyon on Sunday May 10 2015, @07:47AM
Step it up gewg_
http://www.wolframalpha.com/input/?i=32+sq.+meters [wolframalpha.com]
http://en.wikipedia.org/wiki/Square_metre [wikipedia.org]
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by Fnord666 on Sunday May 10 2015, @02:04PM
Re:32 meters squared is 105 feet squared
Huh? Your own link to wolfram alpha says that it converts to 344.4 square feet.
(Score: 2) by takyon on Sunday May 10 2015, @04:05PM
I didn't write 105. I wrote 344 in the summary.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by Fnord666 on Monday May 11 2015, @02:44AM
(Score: 0) by Anonymous Coward on Sunday May 10 2015, @08:53PM
So, the linked Wipipedia page insists that m2 is "square meters" (as does the "disambiguation" page). [wikipedia.org]
Neither page, however, specifies how to abbreviate "meters squared".
Perhaps you could supply that information.
-- gewg_
(Score: 2) by takyon on Monday May 11 2015, @01:42AM
http://mathforum.org/library/drmath/view/57209.html [mathforum.org]
They both mean the same thing.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 0) by Anonymous Coward on Monday May 11 2015, @04:32AM
No. They don't.
If you're talking about ONE SPECIFIC CASE, -then- it is true:
something 1 meter squared.
Something that is 32 meters squared has sides that are 32 meters in length.
No wonder you keep insisting you are right and I am wrong:
You don't understand English.
-- gewg_
(Score: 2) by takyon on Monday May 11 2015, @05:15AM
I give you a C+ in English.
And there is nothing wrong with "32 m2 (344 ft2)".
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 0) by Anonymous Coward on Monday May 11 2015, @03:10PM
It's really simple to express the concept you're trying for:
(32 m)2 or (32 m)^2
Which is read aloud as "thirty-two meters, quantity squared", "the square of thirty-two meters", or some such nonambiguous formulation.
You see, when written as a formula, there is no ambiguity -- standard order of operation we all know from algebra applies; in the absence of parentheses, exponentiation (i.e. m2 or m^2) takes place before multiplication (i.e. 32 m).
When spoken verbally, however, "thirty-two meters squared" is ambiguous -- so the English-speaking technical community (scientists, engineers, and what-not) have collectively settled on (1) generally prefering not to use that formulation and (2) if that formulation is encountered, interpreting it as equivalent to "32 square meters".
(Regarding who understands English how well... Suppose you're right, and this consensus of the English-speaking technical community in fact results from them not understanding English as well as --gewg_. Is it then more useful to defend correct English, or to be able to communicate without misunderstandings?)
(Score: 3, Interesting) by frojack on Sunday May 10 2015, @07:06AM
We had an discussion recently about cleaning up space junk because if imposes risks to future space flights.
Now we are going to park relatively modestly useful space craft in prime (and limited) parking space at the L1 Lagrangian point. There have already been a few space craft planning to use this area [wikipedia.org] for orbital transitions or parking places. Seems we have something of a gold rush for parking space.
No, you are mistaken. I've always had this sig.
(Score: 1, Funny) by Anonymous Coward on Sunday May 10 2015, @07:42AM
Let's put up a parking meter and make a lucrative business out of towing (and potentially returning) all transgressing vehicles, according to L1 parking regulation number 5.3.9.12.4 (Footnote 13)
I'd like to run the storage compound , please. Could I auction off the stored probes after a year?
(Score: 0) by Anonymous Coward on Sunday May 10 2015, @08:38AM
destroy planet after planet and see what happens!