LightSail-2 extends mission

Capitalism in space: The Planetary Society’s satellite designed to test the use of a light sail in orbit, LightSail-2, has now begun an extended mission one year after launch.

It appears that they have successfully used the light sail to delay the decay of the satellite’s orbit, as well as change that orbit slightly. The extension will thus allow them to get a better and more exact understanding of the sail’s capabilities, information NASA will use in its own solar sail demonstration mission, NEA Scout, a cubesat that will use a solar sail to fly to an asteroid.

LightSail-2 successfully raises its orbit using sunlight

Capitalism in space: By raising its orbit by the use of sunlight only, LightSail-2 has confirmed what an earlier Japanese solar sail Ikaros had demonstrated, that it is possible to use solar sails to travel in space.

Since unfurling the spacecraft’s silver solar sail last week, mission managers have been optimizing the way the spacecraft orients itself during solar sailing. After a few tweaks, LightSail 2 began raising its orbit around the Earth. In the past 4 days, the spacecraft has raised its orbital high point, or apogee, by about 2 kilometers. The perigee, or low point of its orbit, has dropped by a similar amount, which is consistent with pre-flight expectations for the effects of atmospheric drag on the spacecraft. The mission team has confirmed the apogee increase can only be attributed to solar sailing, meaning LightSail 2 has successfully completed its primary goal of demonstrating flight by light for CubeSats. [emphasis mine]

The highlighted text notes a secondary but possibly more important engineering achievement here. LightSail-2 was launched as a cubesat. It has now proven that such a cubesat can include a solar sail and use it for purposes of transportation.

Moreover, that this engineering test was funded entirely by private funds proves again that the government is not necessary for great things to be achieved.

They will continue to raise the spacecraft’s apogee for the next month, until the lowering of the perigee causes the spacecraft to get pulled out of orbit by the drag from the atmosphere. That second process will still take about a year.

LightSail-2 successfully deploys light sail

Capitalism in space: The LightSail-2 engineering team today successfully deployed its boxing ring-sized light sail from its cubesat.

All indications are that LightSail 2’s solar sail has deployed successfully. Flight controllers sent the deployment command at approximately 11:45 PDT (18:45 UTC). Telemetry showed the motor count increasing as expected, and the motor appeared to halt at the correct time. LightSail 2’s cameras also appeared to capture imagery as planned.

The mission team will now confirm successful deployment by downloading imagery during subsuquent ground station passes today.

Once checked out, they will begin tests to see how they can use sunlight to change the light sail’s orbit, literally sailing in space.

The wonders of freedom: This mission was privately paid for and built by the Planetary Society.

LightSail 2 released from cubesat; establishes contact

The Planetary Society’s LightSail-2 technology demonstration satellite was released from its carrier vehicle today and successfully established communications with the ground.

The CubeSat, about the size of a loaf of bread, was scheduled to leave Prox-1 precisely 7 days after both spacecraft successfully flew to orbit aboard a SpaceX Falcon Heavy rocket. Following deployment from its spring-loaded enclosure known as a P-POD, LightSail 2 deployed its radio antenna and began transmitting health and status data, as well as a morse code beacon indicating its call sign. The mission team received LightSail 2’s first signals on 2 July at 01:34 PDT (08:34 UTC), as the spacecraft passed over Cal Poly.

…The team will spend about a week checking out LightSail 2’s systems, exercising the spacecraft’s momentum wheel, and taking camera test images before and after deployment of the CubeSat’s dual-sided solar panels. Following the successful completion of these tests, the team will deploy the 32-square-meter solar sail, about the size of a boxing ring. A time for the solar sail deployment attempt will be announced later.

If they successfully deploy the solar sail and use it to maneuver in space, it will the second time the Planetary Society has done it, having deployed LightSail-1 in 2015. That mission has some communications problems, but eventually succeeded in its main engineering mission by testing the sail deployment system.

LightSail-2 will also be the third time a light sail has been flown in space, with the first, Ikaros, deployed by the Japanese in 2010 and flown in solar orbit through 2012. That mission was successful in using sunlight to accelerate the sail.

LightSail deploys its solar sails

Though full confirmation will not come until later tonight, telemetry from LightSail suggests that its solar sails have successfully begun deployment.

Telemetry received on the ground showed motor counts climbing to the halfway point before LightSail traveled out of range. Power levels were consistent with ground-based deployment tests, and the spacecraft’s cameras were on. “All indications are that the solar sail deployment was proceeding nominally,” wrote mission manager David Spencer in an email update.

They will have to wait until the cubesat comes back in range at 2:46 am (Eastern) to see if the deployment completed successfully, as well as download images.

LightSail back in business?

The Planetary Society’s solar sail engineering test called LightSail has re-established communications with the ground, allowing for the possibility that it can finally achieve its solar sail deployment, the main purpose of the mission.

I had previously reported that the sails had deployed, but a commenter correctly noted that only the panels have deployed, not the sails themselves, which need full battery power. The communications problem has been related to a battery charging problem. They are hoping that the batteries will get charged by mid-day today when they will try to deploy the sails.

LightSail deployment scheduled for Tuesday

Assuming all goes well with the orbital preparations today, LightSail will perform its test deployment on Tuesday at 11:44 am.

If successful, this deployment will achieve several significant engineering firsts, the most important of which will be to have demonstrated that a cubesat can be used for such a task. Proving that fact will increase their commercial usefulness for future space endeavors.

Solar sail experiment stymied by software crash

The Planetary Society’s LightSail solar sail test mission, launched as a secondary payload on last week’s Atlas 5 X-37B launch, has fallen silent because of a software problem.

The communications problem occurred before the mission could achieve its main engineering goal of testing the deployment of the solar sail. They still hope to regain communications, but time is limited as the cubesat is in a low orbit that will decade relatively quickly.