#lightsail

Scientists at the California Institute of Technology have taken a major step toward developing lightsails that could one day carry tiny spacecraft to distant star systems.

The new findings detail a method to measure the force of laser light on what are known as "ultrathin membranes." This is research that could help advance the Breakthrough Starshot Initiative's vision of laser-driven space travel.

We Just Got Incredible New Photos of Our Lonely Little World From LightSail 2.

“LightSail 2 is a technology demonstration mission for the most part. And it's been successful so far. In January 2020, the Planetary Society released a paper outlining the mission results. In brief, LightSail 2's solar sails are working, though the spacecraft is still expected to fall to Earth within a year of launch.

The spacecraft carries cameras, of course. Those cameras are there primarily to check on the solar sails. But while doing that, they're capturing some delicious photos of Earth in the background.”

LightSail-2 deploys solar sail, beginning orbital operations (July 23, 2019).

Four weeks after launching on a SpaceX Falcon Heavy rocket from Florida, The Planetary Society’s LightSail-2 spacecraft successfully deployed its solar sail July 23.

Four cobalt-alloy booms unraveled from the main spacecraft bus with the triangular segments of mylar sail material. Once fully unraveled, LightSail 2′s solar sail covers roughly 32 square meters. Deployment occurred at 12:45am EDT over Mexico in range of the mission’s San Luis Obispo, California control center. Two cameras with a 185 degree field of view provided footage of sail deployment and other orbital imagery during the spacecraft’s mission. The spacecraft is orbiting 447 miles above the Earth.

LightSail-2 undergoing preflight sail deployment testing in California in 2016. P/c: The Planetary Society. LightSail-2 is the Planetary Society’s second, larger solar sail testbed spacecraft, having launched the smaller LightSail-1 in 2015. That mission, which launched piggyback with the X-37B spaceplane on an Atlas V rocket, spent 25 days orbiting the Earth and validating the spacecraft’s sail design. Major differences between the two spacecraft include the addition of a reaction wheel to orient the spacecraft and a cluster of mirror’s on the vehicle’s underside that will aid in precise ground-based measurements.

With LightSail-2, the Society hopes to prove that sails could be used for orbit raising and other maneuvers in space, ultimately reducing the cost for cubesats to travel beyond low Earth orbit. Solar Sailing as a technology was first proposed by Planetary Society cofounder Carl Sagan in the late 1970s as a method of deep-space propulsion that utilized photos from the sun as fuel. Much the same way as wind on Earth pushes a ship’s sail, solar sails in space would be propelled by photons from the sun pushing against a large surface area. The Society expects LightSail-2 to remain in orbit for at least a year. As the spacecraft’s apogee, or highest point slowly raises, its perigee, or closest point slowly lowers, eventually causing the sail to plummet into the atmosphere and burn up.

Click here for our coverage of the LightSail program.

The Planetary Society's #LightSail2 is scheduled to deploy its #solar sail today (7/23/19) @ 11:40 PDT

A distinguished Harvard University professor is not backing down from his claims that a piece of extraterrestrial spacecraft technology may be flying past the orbit of Jupiter at this moment.

Avi Loeb, one of the top astronomy professors in the world, boasting of decades of Ivy League professorships and hundreds of publicized works in respected astronomy publications, is remaining defiant that the space object – dubbed as “Oumuamua” – first noticed by Hawaiian astronomers in 2017 could be from another civilization.

“Considering an artificial origin, one possibility is that ‘Oumuamua is a lightsail, floating in interstellar space as a debris from an advanced technological equipment,” Loeb and his colleague Shmuel Bialy wrote in Astrophysical Journal Letters in November, according to the Washington Post.

Since making the shock claim last year, many scientists have criticized Loeb for offering, in their view, the most sensationalist theory of what the object is.

“Oumuamua is not an alien spaceship, and the authors of the paper insult honest scientific inquiry to even suggest it,” Ohio State University astrophysicist Paul M. Sutter wrote in a tweet. Other scientists are more diplomatic and haven’t publicly countered Loeb’s claims, only saying that the object is likely just some sort of rock, whether it’s a piece of an asteroid or a comet.

But Loeb remains stubborn on this theory, and dismisses the claims that it’s a rock, noting that it's moving too fast for an inert rock. He told the Post that the object is long yet no more than one millimeter thick, and that it’s so light that sunlight is moving the object out of the solar system.

“Many people expected once there would be this publicity, I would back down,” Loeb says. “If someone shows me evidence to the contrary, I will immediately back down.”

“It changes your perception on reality, just knowing that we’re not alone,” he continued. “We are fighting on borders, on resources. … It would make us feel part of planet Earth as a civilization rather than individual countries voting on Brexit.”

Even as his theories attracted attention around the world, despite his colleagues’ criticism, Loeb says he’s not afraid of any possible repercussions for spreading his theories and wears it as a badge of honor, showing his unorthodox approach to science.

“The mainstream approach [is] you can sort of drink your coffee in the morning and expect what you will find later on. It’s a stable lifestyle, but for me it resembles more the lifestyle of a business person rather than scientists,” he told the newspaper.