Lasers To Help Clean Up Our Skies

We humans have polluted almost every nook and corner of our planet. Our activities are now casting their shadow beyond the boundaries of Earth. Space debris is a clear and present danger. It's akin to a graveyard of human ambitions, a leftover from our quest to explore the final frontier.

Space debris, or space junk, refers to defunct human-made objects in Earth's orbit, such as old satellites and spent rocket stages. There are over 900,000 objects larger than a softball and millions more the size of marbles zipping around Earth's atmosphere. They are found at altitudes ranging from 100 to 1000 km.

Debris as small as a few millimeters can cause serious damage. This cosmic junkyard could cripple our satellites, jeopardize space flights, and even endanger human space missions.

Now there is new hope on the horizon. A Japanese firm has come up with a mechanism to clear the debris using ground-based lasers.

The company, EX-Fusion, is developing a ground-based laser system to help knock out space junk. The Osaka-based startup has unveiled plans for harnessing lasers to gently nudge the space debris into Earth's atmosphere so that it burns up during re-entry, leaving only ashes. A high-powered laser is being set up at an observatory outside Canberra. EX-Fusion is joining hands with Australia's EOS Space Systems to embark on this mission to clean our planet's outer boundaries. According to reports, during the first phase, these lasers would identify space debris measuring less than 10 centimeters. Experts say this is much tougher than the proverbial task of finding a needle in a haystack. After that, a high-powered laser would be installed, which would target these fragments intermittently to slow them down. After losing momentum, smaller space junk would descend into Earth's atmosphere and burn up during re-entry.

With thousands more satellites planned for launch, the cosmic traffic jam is getting uglier by the day. Since the 1950s, over 15,000 satellites have been placed in Earth's orbit.

These are only estimates, as many satellites are used for military purposes and are rarely disclosed. It is estimated that there are over 8,000 active satellites. With private firms offering cheaper options and a renewed global space race, the number of satellites is set to surge. Every space launch means more debris. There have been various options to sweep outer space, but most of it is in its nascent stage. NASA has an Orbital Debris Program Office, which looks for ways to create less orbital debris and designs equipment to track and remove the debris already in space. The European Space Agency is considering several kinds of "capture mechanisms" to pick up the debris, such as giant nets and robotic arms. While the Japanese space agency is working on a mechanism to develop an electrodynamic tether. There are other proposals, like a "solar sail" to drag space debris to lower orbits, while other experts are designing lasers to blast off this space debris further into outer space.

While space debris has been a concern for decades, efforts to address this junk have only recently gotten the much-needed attention and investment to clear low-earth orbit, which is teeming with space junk.