December 27, 2019

Lasers Learn to Accurately Spot Space Junk (Source: AIP)
Chinese researchers have improved the accuracy in detecting space junk in earth's orbit, providing a more effective way to plot safe routes for spacecraft maneuvers. Scientists have developed space junk identification systems, but it has proven tricky to pinpoint the swift, small specks of space litter. A unique set of algorithms for laser ranging telescopes, described in the Journal of Laser Applications, by AIP Publishing, has significantly improving the success rate of space debris detection.

"After improving the pointing accuracy of the telescope through a neural network, space debris with a cross sectional area of 1 meter squared and a distance of 1,500 kilometers can be detected," said Tianming Ma, from the Chinese Academy of Surveying and Mapping, Beijing and Liaoning Technical University, Fuxin. Laser ranging technology uses laser reflection from objects to measure their distance. But the echo signal reflected from the surface of space debris is very weak, reducing the accuracy. Previous methods improved laser ranging pinpointing of debris but only to a 1-kilometer level. (12/24)

Finding Stars That Vanished—by Scouring Old Photos (Source: Ars Technica)
Before the advent of digital imaging, astronomy was done using photographic plates. The results look a bit like biology experiments gone bad (of which I've perpetrated more than a few), with a sea of dark speckles of different intensities scattered randomly about. To separate the real stars from any noise, astronomers would take multiple images, often at different colors, and analyze the results by eye before labeling anything an actual star. Sounds tough, but by 50 years ago, astronomers had already managed to catalog hundreds of millions of stars in all areas of the sky.

These days, automated telescopes, digital imaging, and software pipelines mean that we can do equivalent surveys with greater sensitivity in a fraction of the time. But that doesn't mean the old surveys have lost their value. The original photographs provide data on how the sky looked before the relative motion of objects (and their occasional explosions) rearranged the sky. To get a better sense of just how much the sky has changed, a group of researchers has been comparing the old photographs and the modern survey data to figure out what stars went missing.

After whittling down a large list of candidates, the team came up with 100 things that looked like stars a century ago but no longer seem to be with us. To go back far enough in time, the VASCO team relied on the US Naval Observatory's catalog of objects, which combines the results of several surveys done on photographic plates. All told, this catalog contains over a billion objects. For modern data, the team used the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) database, which contains even more objects. (12/24)

China Launches Environmental Satellite Built in Cooperation with Brazil (Source: SpaceFlight Now)
The sixth in a series of environmental monitoring satellites jointly developed by China and Brazil successfully launched Dec. 20 on top of a Long March 4B rocket. The CBERS 4A Earth observation satellite rode the Long March 4B rocket into a 385-mile-high (620-kilometer) polar sun-synchronous orbit from the Taiyuan space base in northern China’s Shanxi province. (12/21)

A 'Wild Environment': Uncertain Safety Rules Await Space Tourists (Source: Politico)
When buckling up for a road trip, passengers can be confident the vehicle has met a range of federal and state safety regulations — from the durability of the car's frame to reliability of the brakes and performance of the seat belts. But when the first space tourists strap in for their maiden voyage to space in 2020, they’ll have no such guarantees. No federal regulator will have certified whether the spacecraft is safe — and only a patchwork of authorities exists to investigate a private space disaster.

The commercial spaceflight industry is instead governed by a confusing jumble of oversight authorities, and no agency has been empowered to ensure the safety of space travel — largely leaving the manufacturers themselves responsible for the flightworthiness of their own spacecraft. Oversight agencies will have to quickly catch up before a possible disaster creates a backlash that could hobble the industry before it takes off, warn top government and industry officials.

For instance, the Federal Aviation Administration can force companies to demonstrate the public will be safe near space launch facilities but it cannot govern the safety of the people on board. In fact, the FAA is actually barred from implementing any safety rules for commercial spacecraft until 2023 to spare the fledgling industry burdensome regulations. That's even though Virgin Galactic expects to fly nearly 1,000 people to space by 2022, according to paperwork filed with the SEC. (12/25)

Ariane Anniversary: It's 40 Years Since Europe Launched its First Rocket (Source: EuroNews)
Forty years ago, on December 24, 1979, the first Ariane rocket took off from Kourou in Guyana, marking Europe’s new independent membership in the international race for space. Now, forty years later, the European space program has executed 250 launches and put almost 400 satellites into orbit. (12/24)