15 Matching Annotations
  1. May 2024
  2. Apr 2024
    1. If you plan on setting on your desk, unscrew the bottom plate and scrape off the hardened rubber feet and super glue some new ones on. I get the clear rubber kind from Ace Hardware (Part No. 5182381).

      Hermes Rocket feet repair advice.

  3. Aug 2023
    1. NASA’s Perseverance rover has been diligently collecting rocky samples from Mars to stow them away on the planet’s dusty surface while engineers work to develop a rocket that can launch off of another world as a crucial step in the process of retrieving the samples.

      So exciting!

  4. May 2023
  5. Dec 2022
  6. Mar 2022
    1. The amount of thrust produced by the rocket depends on the mass flow rate through the engine, the exit velocity of the exhaust, and the pressure at the nozzle exit. All of these variables depend on the design of the nozzle.
    2. which means that the Mach number is equal to 1.0 in the throat

      If the hot exhaust flow weren't choked at the throat, will the Mach number still be 1? But, why would the Mach number be 1 in the first in a choked flow?

    3. rocket thrust equation

  7. Dec 2020
    1. Montreal was aghast. Campbell's rulingwas considered an act not of justice but of vindictiveness, theEnglish-speaking boss thwarting the aspirations of theFrench-speaking populist hero. Richard had led the Canadiens tothree Stanley Cups and had scored 50 goals in 50 games, but hehad never won a scoring title and was on the brink of his first.With teammate Bernie Geoffrion three points behind him, it wasapparent that Richard wouldn't win it this year, either.

      That is so frustrating. Suspend him for his last three games? So petty. Could have just fined him if he was going to make a statement like that.

    1. Maurice Richard­-le Rocket, Montreal’s homegrown French-Canadian star from the city’s blue-collar Nouveau-Bordeaux neighborhood, the world’s greatest hockey player to that time — carries the puck in the Boston zone. Hal Laycoe steps in his way. The 12,023 fans brace themselves.

      WORLDS greatest?? Oh wow

  8. Sep 2017
    1. – Two days ago, one of our rocket buses was denied permission for an emergency landing.

      I have never seen this movie, so the start of this scene is a bit confusing. Why are these people secluded from what seems like the rest of society? I also notice that there are no people of color aboard on this "rocket bus;" it seems like only the upper class are included so far.

  9. May 2016
    1. Simulation tests indicate that manual control of the capsule attitude during retrograde firing will be a difficult task requiring much practice on the part of the pilot. By changing the command function from acceleration to rate, the task complexity will be greatly reduced and the developmental effort on display and controller characteristics can be reduced accordingly
    2. There is a natural reluctance to relinquish the mechanical linkage to the solenoid valves but the redundant fly-by-wire systems offer mechanical simplification with regard to plumbing and valving hydrogen peroxide
    1. Three retro rockets fire for 10 seconds each. They are started at 5 second intervals, firing overlaps for a total of 20 s. Delta V of 550 ft/s (168 m/s) is taken off forward velocity.
  10. Dec 2015
    1. On Monday evening, for the first time in aerospace history, a rocket took off vertically from its launchpad, pierced the boundary of space and deposited its second stage into orbit, and returned intact to Earth, landing upright not far from where its journey began.

      https://www.youtube.com/watch?v=1B6oiLNyKKI SpaceX Falcon 9 first stage vertical landing