« July 27, 2021 | Main | July 29, 2021 »

July 28, 2021 Archives

Wednesday, July 28, 2021

CONTINUITY: NASA: RS-25 Rocket Engine “Improved”

Forty years after it first flew as the Space Shuttle Main Engine, the Aerojet Rocketdyne RS-25 rocket engine, which was originally designed for a service life of 27,000 seconds and 55 starts, has been “improved”, delivering a service life of 1700 seconds (6.8% of the original) and 4 starts (7.3% of the original). Thrust has been increased by 6%, along with “some cost savings”—the cost for the 24 RS-25 engines intended for the Space Launch System (SLS) comes to around US$ 146 million per engine.

The engines, routinely refurbished and reused in the Space Shuttle program, will be discarded as twisted wreckage in the briny deep on each flight of the SLS.

Elon Musk estimates the cost of the SpaceX Raptor engine, which has slightly more thrust (albeit less fuel efficiency) than the SL-25, and is intended to be reused numerous times, at less than US$ 1 million for current engines, and a quarter of that for improved versions in volume production.

Posted at 14:27 Permalink

TRACKING WITH CLOSEUPS: Tiny Electronic Components

Posted at 13:07 Permalink

THE HAPPENING WORLD: Do It Yourself Challenge—CNC Mill to Automated Gun Turret

Bioshock Infinite automated gun turret

Posted at 12:08 Permalink

THE HAPPENING WORLD: Who Is an “Astronaut”?

First, it was “What is space?”, now it's who deserves to be called an “astronaut”. (I don't know why Blue Origin's marketing department hasn't seized on my suggestion to call those who fly on Branson's ride below the Kármán line “asterisknauts”.)

As Scott Manley observes, those who fly on vehicles operated by coercive governments, or even those in their employ who do have not yet flown, have been called “astronauts”, including politicians, such as the current NASA administrator, “Ballast Bill”, who went on a taxpayer-funded junket into space. I think the answer is to make the term “astronaut” one of derision, applied to civil service space cadets who have appropriated a noble title rightly belonging to genuine pioneers of space exploration. There's a parallel to this: nobody calls airline pilots or passengers “intrepid aeronauts” these days.

As for those who travel above the Kármán line today, how about “spacers” or, for those who see it as a New Age experience, “space cases”?

Posted at 11:12 Permalink

CONTEXT: A Banana a Day

Posted at 10:08 Permalink