For a long time, Rocket Propellant-1, or RP-1, reigned supreme as the fuel of choice for the first stage of rockets. This highly refined form of kerosene, which was derived from jet fuel, powered the Saturn, Delta, Atlas, and Soyuz rockets throughout the 20th century. It even served as fuel for modern rockets like the Falcon 9.
RP-1 has the benefit of being dense, which means a lot of fuel can be packed into a relatively small tank. However, RP-1 isn't the most efficient fuel, a measurement known as specific impulse. Liquid hydrogen, by contrast, has a really high specific impulse. But because it is not at all dense, it can't efficiently be used as a first stage fuel.
This is one reason a number of major new rocket engines developed during the last decade, including SpaceX's Raptor and Blue Origin's BE-4 engines, have been designed to use methane as a fuel. It represents a compromise between RP-1 and hydrogen—not quite as dense as the former, and with not quite as high of a specific impulse as the latter. Methane is also useful if you want to go to Mars, because it is relatively abundant in the Red Planet's thin atmosphere and could be used to refuel an ascent vehicle.
The dating platform is testing letting women take control of sending the first message to a match.
Twitter asks its members to help shape new rules banning "dehumanising speech".
It's used, but still the cheapest Dot to date.
The company's eagerly awaited "affordable" version of its GFX 50S trims features you probably won't miss -- and a couple you might.
A survey of 250,000 people have made their appliance alliances.
Assa Abloy acquired August last year, and now we're getting a look at what that means for Yale and August smart locks.
Because there ain't no party like a cloud storage party
A year after Microsoft reintroduced placeholders for Windows users of OneDrive in the form of "Files On-Demand", Mac users of the cloudy file service are getting the same love.…
And we have liftoff!
BuzzFeed claims to have a warrant suggesting the British national, 55, was arrested during a video shoot.
Someone should tell mobile industry. Oh, here we go
The Czech Republic and Hungary top the world for mobile video performance – even though they don't have the fastest networks.…
The departure of Kevin Systrom and Mike Krieger is the latest test for parent company Facebook.
A decade after Google brought us Android, these fixes are still MIA.
Fancy hopping across the city in your own air taxi? UberAir could be your answer. And to get you to your aircraft, Uber is planning on building a network of skyports to help you board in style.
By 2025, Volkswagen expects to sell 1 million MEB-based EVs.
The developer could have help in releasing the last two episodes of Clementine's story despite its shutdown.
Joins growing list of senior civil servants leaving public sector
Exclusive Mayank Prakash, chief digital officer and CIO of the UK Department for Work and Pensions has quit today, The Register can exclusively reveal.…
But Labour's Angela Eagle says tech giants should work for the "common good" and not just profit.
Except that Eric S Raymond doesn't like codes of conduct
Speculation and debate still surround Linus Torvald's decision to step back from Linux kernel development for a while, but the next kernel release candidate landed with far less sturm und drang.…
Think there's no difference between the cameras on the iPhone XS and iPhone X? See for yourself.