Elon Musk has opened up about a big design change to SpaceX's interplanetary spaceship.
Starship – the vehicle SpaceX is developing to take people to and from other remote destinations.
In a recent interview with Popular Mechanics, Musk explained what motivated the switch. Expense was one factor. Carbon fiber costs $ 135 per kilogram, and 35 percent of the stuff needs to be scrapped – "The SpaceX founder and CEO said" you cut the fabric, and some of you can not use it. " So the true cost of the material is nearly $ 200 per kg, compared to just $ 3 for stainless steel, he added. [Images: SpaceX’s Giant Spaceship for Mars Colony & Beyond]
Stainless steel's high melting point is a big advantage, Musk told Popular Mechanics Editor-in-Chief Ryan D 'Agostino.' "So, typically aluminum or carbon fiber, for a steady-state operating temperature, you're really limited to about 300 degrees Fahrenheit." [150 degrees Celsius] It's not that high, "Musk said. "You can take little, letter excursions above that, maybe 350 [degrees F, or 180 degrees C]." Four-hundred [degrees F, or 200 degrees C]you're really pushing it. "It weakens." And there are some carbon fibers that can take 400 degrees Fahrenheit, but then you But steel, you can do 1,500, [or] 1,600 degrees Fahrenheit [820 to 870 degrees C]. "
So Musk detailed SpaceX's plans for Starship's innovative heat-shield system, which will employ transpiration cooling.
" You just need, essentially, two [stainless-steel] layers of paper in the sandwich layer, and then you have micro-perforations on the outside – very tiny perforations – and you bleed water, or you could bleed fuel through the micro perforations on the outside, "Musk told D'Agostino.
The entire interview is definitely worth a read; check it out here.
The 100-passenger Starship wants to launch a super rocket called the Super Heavy. Until recently, BFR, which stood for "Big Falcon Rocket."
The company has already built a reduced-scale Starship prototype, which aims to "hopping" excursions that will stay firmly within Earth's atmosphere.
Musk said on Jan. 5 that the company was aiming to fly this hopper for the first time within four to eight weeks. However, Mother Nature has complicated that timeline. Strong winds at SpaceX's South Texas site knocked the hopper's fairing over, and it likely took a couple of weeks to fix the damage, Musk said via Twitter on Wednesday (Jan. 23).
I just heard. 50mph winds broke the mooring blocks late last night & fairing what blown over. Will take a few weeks to repair.
– Elon Musk (@elonmusk) Jan. 23, 2019
Musk has said.
Mike Wall's book on the search for alien life , "Out There" (Grand Central Publishing, 2018, illustrated by Karl Tate), is out now. Follow him on Twitter @michaeldwall . Follow us @SpaceTotcom or Facebook. Originally published on Space.com.