2. Water tracks in Antartica look similar to features on Mars
10. Nextbigfuture – Skylon has UK government and private funding for its single stage to orbit spaceplane. Flight tests of an engine for the UK Skylon spaceplane are expected by 2020 and a prototype engine is expected by 2017.
Two Synergetic Air-Breathing Rocket Engines (SABRE) will power the Skylon space plane — a privately funded, single-stage-to-orbit concept vehicle that is 276 feet (84 meters) long. At take-off, the plane will weigh about 303 tons (275,000 kilograms). The two SABREs are located on the tips of the delta wings attached midway down the Skylon’s dart-like fuselage, powering it to deliver up to 33,000-pounds (15,000 kg) into orbit. The Skylon development is estimated to take 9.5 years (2023 or so) and cost $9.518 Billion (2004 prices). The development program will produce a vehicle with a life of 200 flights, a launch abort probability of 1% and a vehicle loss probability of 0.005%. Assuming a production run of 30 vehicles each vehicle would cost about €565 M. In operation it should be capable of achieving a recurring launch cost of €6.9 M per flight or less.
The designed thrust/weight ratio of SABRE is up to 14 compared to about 5 for conventional jet engines, and 2 for scramjets. This high performance is a combination of the denser cooled air, requiring less compression. More importantly, the low air temperatures permit lighter alloy to be used in much of the engine. Overall performance is much better than the RB545 engine or scramjets.Fuel efficiency peaks at about 3500 seconds within the atmosphere.Typical all-rocket systems peak around 450 and even “typical” nuclear thermal rockets at about 900 seconds.The combination of high fuel efficiency and low mass engines permits a single- stage-to-orbit approach, with air breathing to mach 5.14+ at 28.5 km altitude, and with the vehicle reaching orbit with more payload mass per take-off mass than just about any non-nuclear launch vehicle ever proposed.