Is New Zealand the world’s best rocket-launching site?


THE Mahia peninsula, on the east coast of New Zealand’s North Island, has been a holidaymakers’ haven for decades. It offers sandy beaches, hot springs and scenic trails. And, for those of a technological mindset, it also offers the world’s first private orbital-rocket-launching base.

Launch Complex 1, as this base is known, sits at the tip of the peninsula and thus on the edge of the South Pacific ocean. Beyond it, the waters stretch uninterrupted by land for thousands of kilometres (see map). Few ships ply the area and few aircraft fly over it. A misfire or rocket stage falling into this wide expanse will thus inconvenience no one. Mahia is farther from the equator than most launch sites (lifting off from an equatorial pad extracts maximum additional velocity from Earth’s spin), but that is also an advantage. The sacrifice of some spin-assisted lift makes it easier to reach certain sorts of useful orbit, such as those that pass over the poles.

The builder and owner of this paradise of rocketry is Rocket Lab, a firm which, though American (its headquarters are in Huntington Beach, California), was founded and is led by a New Zealander. By his own admission, Peter Beck, the Kiwi in question, has been obsessed with rockets since childhood. Now, he is close to turning that obsession into a successful business.

Rocket Lab’s launch vehicle, a multi-stager called “Electron”, underwent its first test in May 2017. Its second happened on January 21st, 16 days before the more widely publicised launch of a much bigger experimental vehicle, SpaceX’s Falcon Heavy. Unlike the Falcon Heavy, though, which carried an old sports car into space as a joke, the Rocket Lab test had a real payload, in the form of three small, commercial satellites. (It also carried a reflective, geodesic sphere dubbed the Humanity Star, which was visible to the naked eye when it passed over at night until it re-entered the atmosphere in March.) That second test having gone well, Mr Beck now deems the time for testing over. Electron’s third outing, scheduled for sometime in the fortnight starting April 20th, will be a fully commercial flight.

On its launch pad an Electron stands 17 metres tall and has a diameter of 1.2 metres. The engines that power it are named after New Zealand’s most famous physicist, Lord Rutherford, who discovered the atomic nucleus and much else. The first stage has nine Rutherford engines. The second has but one. These lift into orbit a third, “kick” stage that carries the payload. The kick stage is fitted with a different sort of rocket engine, Curie, which can be started, shut down and restarted as needed. That lets it manoeuvre the kick stage and thus dispatch different parts of the payload into different orbits.

All systems go

Both Rutherford and Curie are made from components that have been 3D-printed from sintered metallic powder, rather than being cast and machined in the conventional way. This speeds things up. Rocket Lab’s facility in California can produce a new engine from scratch in just a few days. The engines also use electric turbopumps, rather than the more conventional option of gas turbines, to push propellant into their combustion chambers. This eliminates the complex plumbing required to make a gas turbine work. The rocket itself is made of a carbon-fibre composite that is much lighter than the metal usually employed for rocket bodies. This reduces the launch mass, saving fuel.

Though 17 metres is pretty lofty (about the height of four stacked double-decker buses), it pales beside, say, the 70 metres of SpaceX’s Falcon 9 launcher, the firm’s current commercial offering. The two rockets, however, are aimed at different markets. SpaceX’s main businesses are lifting large, expensive satellites into orbit and carrying provisions to the International Space Station. Rocket Lab has its eyes elsewhere—on the fast-growing market for “CubeSats”, which are small and cheap.

A CubeSat can be anything a customer wants to launch that will fit inside one of a number of standard cuboids. The CubeSats on board the launch in January were an Earth-imaging satellite and two weather and ship-tracking satellites. Those on the upcoming mission belong to various telecommunications companies.

Large communications satellites of the sort SpaceX deals with are usually boosted into what are known as geosynchronous orbits, 35,786km above the equator. These take 24 hours to complete, so that a satellite in such an orbit will appear to hover over the same point on Earth’s surface. CubeSats, which generally operate in packs, occupy much lower orbits. Often, such orbits are sun-synchronous, meaning that a satellite passes over the same spots on Earth’s surface at the same local times every day, which makes changes below easier to spot. Fleets of CubeSats can thus carry out large-scale monitoring. Sun-synchronous orbits pass almost over Earth’s poles at altitudes of around 500km. Manoeuvring CubeSats into such orbits is Curie’s job.

At the moment, customers who want to use an Electron to launch the most popular design of CubeSat, a 3U (which measures 10cm x 10cm x 30cm and weighs no more than 4kg), can do so for around $240,000 (ie, $60,000 a kilogram). That is a premium price; a trip to low Earth orbit is possible on a Falcon 9 and costs $2,700 a kilogram. But Rocket Lab believes that it offers a premium service. Unlike its competitors’ launchers, into which CubeSats are packed almost as an afterthought if there happens to be space available once the main payload is accounted for, its vehicle is dedicated to CubeSat launches.

The intention is that the location of Launch Complex 1, combined with the Curie-steered kick stage, will give customers a wide range of orbits to launch into. The complex is licensed to dispatch a rocket every 72 hours for the next 30 years. That proposed launch frequency means satellites can be got away quickly. Mr Beck claims that Rocket Lab’s decision to build Launch Complex 1 is coincidental to his nationality. In his view Mahia really is the best available site. Time will tell if he is right.



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