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Polizeiposaune

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Some of the debris from a collision may end up in an orbit with a higher apogee, perigee will necessarily still be at or below the altitude of the last collision and will be subject to some of the same low-orbit aerodynamic drag that starlink satellites experience; passes through lower altitudes will apply drag that will first drop the apogee and will then eventually cause the debris to reenter.

Once the birds are in orbit, satellite internet is vastly superior to fiber in speed of deployment.

Fiber requires custom engineering at the city block level and a single rotten utility pole can block deployment.

I say this as someone who waited for fiber and is happily using it now.

I (an American) once arrived in a hotel room in Finland, sleep deprived after a long couple flights, flipped on the TV and saw a game of Pesäpallo. Made me wonder what I was seeing and what might have caused me to hallucinate..

Sogen Kato 1 month ago

It's not a scam. It's the difference between annuities (longevity insurance) and savings.

If you wanted all pensions to provide a death benefit in addition to the annuity you'd need to either significantly reduce payouts to the living or significantly higher payments into the pension fund.

Sogen Kato 1 month ago

Sounds like "Respect for the Aged Day" doubles as "Audit the Pensioners Day".

Smart bomb targeting is more of a subset of the tech required for precision landing.

Smart bombs just need to get to the target coordinates. A reusable rocket needs to get there with zero velocity, while pointed straight up, with minimal pitch/yaw/roll.

Pretty much all of the barge landing failures shown in "How Not to land an Orbital Rocket Booster" would have been accurate enough to put a warhead on target.

"The air leaks escalated on Friday from a pound of air per day to two pounds, according to a senior NASA official who asked not to be named.

Russian cosmonauts Sergey Kud-Sverchkov and Sergei Mikayev were using a saw to break into an area where they believed they could access the crack leaking air, the NASA official said.

NASA officials disagreed with this method, the NASA official added, prompting mission control in Houston to order safe-haven procedures."

Their terminology is odd. The thing you move while playing is generally called the hand slide. There's nearly always a separate tuning slide located in the crook of the bell section.

(Some relatively rare instruments like the Shires Alto do "tuning in slide" with a mechanism for fine adjustment in the hand slide).

If you're also moving the tuning slide in the middle of a piece you're probably a bass trombonist doing the now-impossible glissando (see https://www.youtube.com/watch?v=fWJPeA_1g48) in the Bartok concerto for orchestra.

Where would you put the other ballast?

You've got two large tanks making up the bulk of the stage's structure - one for oxidizer, one for fuel. They have large diameter pipes that feed propellant to the engines. You can't mix the ballast with either the oxidizer or fuel, and you can't feed the engines from anywhere but the propellant tanks...

Wasn't a bad weld; it was a bad interaction between liquid or solid oxygen and what were previously thought to be inconsequential defects in the composite-overwrapped pressure vessel the helium was loaded into.

Quoting from one of the press releases:

"The recovered COPVs showed buckles in their liners. Although buckles were not shown to burst a COPV on their own, investigators concluded that super chilled LOX can pool in these buckles under the overwrap. When pressurized, oxygen pooled in this buckle can become trapped; in turn, breaking fibers or friction can ignite the oxygen in the overwrap, causing the COPV to fail. In addition, investigators determined that the loading temperature of the helium was cold enough to create solid oxygen (SOX), which exacerbates the possibility of oxygen becoming trapped as well as the likelihood of friction ignition.

"The investigation team identified several credible causes for the COPV failure, all of which involve accumulation of super chilled LOX or SOX in buckles under the overwrap."

https://web.archive.org/web/20170216160231/http://www.spacex...

The weight of the propellant helps hold the rocket on the pad during the test fire, reducing how much force the hold-downs need to exert to keep the rocket on the pad, and stressing the rocket's structure in the same way it will be stressed at launch.

Test fires with a near-empty rocket would put considerably more force on the pad's hold-downs and the corresponding parts of the rocket's structure.

Blue also had a fuelled 2nd stage on top of the booster for the static fire, which is not out of the ordinary.

SpaceX has a "cap" that is held down with cables that it uses when it needs to test-fire a first stage by itself at its McGregor test site; static fires at launch sites are usually done with the 2nd stage on top.

Does Blue Origin not have another pad? (Did they blow up a pad or a test stand?)

The explosion happened at their only completed pad.

They reportedly have a second pad under construction (for the larger "9x4" variant of New Glenn) but I've not seen a lot of detail about how far along it is.

Would not be surprised to see them accelerating construction of the new pad.