Skip to main content

NASA’s climate-monitoring space laser is the last to ride to space on a Delta II rocket

This weekend, NASA is launching a new, high-tech satellite to monitor the planet’s glacier and sea ice levels — with space lasers, naturally. ICESat-2 will be a huge boon for climatologists, and it’s also a bittersweet occasion: it will be the final launch aboard the trusty Delta II rocket, which has been putting birds in the air for nearly 30 years.

Takeoff is set for 5:46 AM Pacific Time Saturday morning, so you’ll have to get up early if you want to catch it. You can watch the launch live here, with NASA coverage starting about half an hour before.

Keeping track of the Earth’s ice levels is more important than ever; with climate change causing widespread havoc, precise monitoring of major features like the Antarctic ice sheet could help predict and understand global weather patterns.

Like Aeolus, which launched in July, ICESat-2 is a spacecraft with a single major instrument, not a “christmas tree” of sensors and antennas. And like Aeolus, ICESat-2 carries a giant laser. But while the first was launched to watch the movement of the air in between it and the ground, the second must monitor the ground through that moving air.

It does so by using an industrial-size, hyper-precise altimeter: a single, powerful green laser split into six beams — three pairs of two, really, arranged to pass over the landscape in a predictable way.

But the real magic is how those lasers are detected. Next to the laser is a special telescope that watches for the beams’ reflections. Incredibly, it only collects “about a dozen” photons from each laser pulse, and times their arrival down to a billionth of a second. And it does this 10,000 times per second, which at its speed means a pulse is bouncing off the Earth every 2.3 feet or so.

As if that wasn’t impressive enough, its altitude readings are accurate down to the inch. And with multiple readings over time, it should be able to tell whether an ice sheet has risen or fallen on the order of millimeters.

So if you’re traveling in the Antarctic and you drop a pencil, be sure to pick it up or it might throw things off.

Of course, it’s not just for ice; the same space laser will also return the exact heights of buildings, tree canopies, and other features. It’s a pity there aren’t more of these satellites — they sound rather useful.

Although ICESat-2 itself is notable and interesting, this launch is significant for a second reason: this will be the final launch atop a Delta II rocket. Rocketry standby United Launch Alliance is in charge of this one, as it has been for so many others.

Introduced in 1989, the Delta II has launched everything from communication satellites to Mars orbiters and landers; Spirit and Opportunity both left the Earth on Delta IIs. All told more than 150 launches have been made on these rockets, and if Saturday’s launch goes as planned it will be the 100th successful Delta II launch in a row. That’s a hell of a record. (To be clear, that doesn’t mean 50 failed; but a handful of failures over the decades have marred the launch vehicle’s streak.)

A Delta II launching for the Aquarius mission in 2011.

One charming yet perhaps daunting idiosyncrasy of the system is that someone somewhere has to literally click a button to initiate takeoff — no automation for this thing; it’s someone’s job to hit the gas, so they better look sharp.

The ULA’s Bill Cullen told Jason Davis of the Planetary Society, for his epitaph on the rocket:

Yes, the Delta II engine start command is initiated by a console operator. The launch control system is 25 years old, and at the time this used a ‘person in the loop’ control which was preferred compared to the complexities of a fault-tolerant computer system.

So why are we leaving this tried and true rocket behind? It’s expensive and not particularly big. With a payload capacity of 4 tons and a cost (for this mission anyway) approaching a hundred million dollars, it’s just not a good value any more. Not only that, but Launch Complex 2 at Vandenberg Air Base is the only place left on Earth with the infrastructure to launch it, which significantly limits the orbits and opportunities for prospective missions. After ICESat-2’s launch, even that will be torn down — though hopefully they’ll keep the pieces somewhere, for posterity.

Although this is the last Delta II to launch, there is one more rocket left without a mission, the last, as it were, on the lot. Plans are solid yet, but it’s a good bet this classic rocket will end up in a museum somewhere — perhaps standing upright with others at Kennedy Space Center.

from TechCrunch


Popular posts from this blog

Android blatantly copies the iPhone X navigation gestures

Google unveiled some of the new features in the next version of Android at its developer conference. One feature looked particularly familiar. Android P will get new navigation gestures to switch between apps. And it works just like the iPhone X.“As part of Android P, we’re introducing a new system navigation that we’ve been working on for more than a year now,” VP of Android Engineering Dave Burke said. “And the new design makes Android multitasking more approachable and easier to understand.”While Google has probably been working on a new multitasking screen for a year, it’s hard to believe that the company didn’t copy Apple. The iPhone X was unveiled in September 2017.On Android P, the traditional home, back and multitasking buttons are gone. There’s a single pill-shaped button at the center of the screen. If you swipe up from this button, you get a new multitasking view with your most recent apps. You can swipe left and right and select the app you’re looking for.If you swipe up o…

Square launches restaurant point-of-sale platform

Square, which has already made its way into retail stores and service-based businesses (think hair salons, massage therapists, etc), is officially getting into the restaurant business with the launch of Square for Restaurants. Square for Restaurants is a point-of-sale system that handles everything from menu updates, floor layouts, employee scheduling, performance tracking to tip splitting.Usually, restaurants have “some old legacy thing or something else,” Square Seller Lead Alyssa Henry told me.“Historically, we’ve not served this customer segment very well,” Henry said. “With Square for Restaurants, we’re excited to finally be able to serve this customer segment and deliver on a couple of key things that are core to Square but also highly valued by sellers of all types.”This new product is designed to be fast, self-serve, elegant and cohesive, Henry said. It also integrates seamlessly into Square’s existing ecosystem that includes Payroll, Capital and more. Given Square’s ownership…

State Farm sponsors popular Fortnite streamer DrLupo

DrLupo, one of the biggest names and most recognizable voices in Fortnite streaming, has closed a sponsorship deal with State Farm.Bejanmin “DrLupo” Lupo has nearly 3 million Twitch followers and often plays with the world’s most popular streamer, Tyler “Ninja” Blevins. Beloved for his talent and his personality alike, Lupo has also worked as a caster for various Fortnite tournaments and events. Last year, DrLupo held a charity stream for St. Jude’s Research Hospital and raised $1.3 million.State Farm Marketing Director Ed Gold had this to say:DrLupo is one of the world’s most followed Fortnite streamers. His philanthropic efforts and massive fanbase make him an ideal partner as we continue to amplify our esports programming and efforts with the gaming community.This marks State Farm’s first sponsorship of an esports athlete. The sponsorship will include support of the stream through branded replays, live in-stream stunts and product integration (here’s me trying to imagine integratin…