SpaceX’s Falcon Heavy Launches on 3rd Mission

The world’s most powerful operating rocket took flight again early on Tuesday morning.

SpaceX’s Falcon Heavy blasted off from Kennedy Space Center in Florida at 2:30 a.m. Eastern time, its powerful boosters lighting up the Space Coast with fiery trails, and later creating loud sonic booms as two of its flaming launch vehicles touched down successfully on landing pads at Cape Canaveral Air Force Station.

It was the third trip for Falcon Heavy. The first test launch occurred in 2018 and the second in April when it carried a Saudi telecommunications satellite to orbit. This time it’s carrying 24 satellites for the Defense Department and other customers, and Mr. Musk called it SpaceX’s “most difficult launch ever.” A successful mission could lead to additional business from the United States government for Falcon Heavy.

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One of SpaceX’s major selling points for those who need to go to space — including the United States military, NASA and private companies — is the cost-effectiveness of the company’s reusable rockets. SpaceX has landed and used many of its rockets again, including the two side boosters of this Falcon Heavy, which came back from space in April. This was the first time the Defense Department has allowed its hardware to be launched aboard a previously used rocket.

Those twin boosters landed upright and intact on landing pads at Cape Canaveral. But minutes later, the rocket’s center booster fared more poorly.

The booster attempted to land on a drone ship, called Of Course I Still Love, off the Florida coast in the Atlantic Ocean. But live video from the ship showed the vehicle missing its target and making an explosive landing in water.

It was the second time that a Falcon Heavy’s center booster failed to make its landing — the touchdown was successful in April. SpaceX had warned that this particular return would be even more challenging because of the speed at which the booster approached the floating platform.

While the company did not land all three boosters, it said that many of the satellites it carried to space were deployed to their orbits. Those deployments were expected to continue for a few hours into Tuesday morning as the spacecraft adjusted its course.

The mission is called Space Test Program-2, and is a partnership between the Defense Department, NASA, the National Oceanic and Atmospheric Administration and a number of private companies. The 24 separate satellites — including an Air Force satellite for basic research as well as cremated remains of 152 people — were packed together in an integrated payload that will be gradually deployed to a variety of orbits. Below is some of the rocket’s most interesting cargo.

The Planetary Society’s LightSail-2 cubesat has waited a decade to launch into space. First proposed and championed by Carl Sagan in the 1970s, this satellite is the size of a loaf of bread and is carrying what is known as a solar sail.

Solar sailing is much like sailing in the ocean. Instead of canvas, LightSail-2 will use mylar sails — nearly 20 miles of them — that open wide to collect as much sunlight as possible. Photons from the sun don’t have any mass, but they do have momentum, and that is just enough to slightly nudge the solar sails, like wind on the open ocean. The cubesat includes a momentum wheel so that engineers on the ground can steer the sail.

A week after launch, the massive sails will spread out and begin using sunlight to lift the cubesat into a higher orbit. The goal is to reach 450 miles above Earth, which would make LightSail-2 the first solar sail to use only the power of sunlight to enter a high orbit. It would then orbit Earth for about a year.

“We’ve made all sorts of vital and very significant improvements to the spacecraft. So I’m very excited about this.” said Bill Nye, the “science guy” and chief executive of the Planetary Society.

Proving the technology works would have significant implications for the future of deep space exploration. When robotic space explorers launch, they carry limited fuel. But solar sailing could provide an alternative propulsion method with nearly limitless fuel, improving the prospects of exploring the farthest reaches of our solar system, or even possibly a journey to other stars.

A NASA payload, this small satellite is a test of rocket fuel that is more environmentally friendly.

Most spacecraft use a propellant called hydrazine, which is highly toxic. To even be near hydrazine, a person must wear a protective Hazmat suit.

This new, less toxic fuel is made of a hydroxyl ammonium nitrate fuel/oxidizer blend, called AF-M315E that was originally developed by the Air Force but never used in space. Not only does this green propellant pose less of a threat to humans handling it, but it’s also more efficient.

To track missions in deep space, NASA and other space agencies rely on radio signals, waiting for them to traverse the long distances. Robotic probes constantly call home to Earth to confirm the current time and their location. But space agencies need a more timely way to track their spacecraft and their future human missions.

Atomic clocks track vibrations inside an atom like cesium, to measure time accurately. Aboard Global Positioning System satellites orbiting Earth, atomic clocks help precisely triangulate distances traveled over periods of time. But the technology has never been used in deep space. If the Deep Space Atomic Clock is tested successfully, future missions in deep space could navigate the solar system with something like GPS.