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Comment Re:A fantastic achievement (Score 4, Informative) 96

As the Universe is expanding, far away stars seem "redder" than closer stars.
As such, while JWST is partially "blind" for close stars, it can see the "red-shifted" and "infrared shifted" radiation generated.
Adding another sensor would make the alignment of mirrors even more complex than it is now, and the existing sensors were proven valuable enough not to be replaced.
Also, there is no value in putting an optical telescope in a Lagrange point. A new Hubble in Earth orbit would have been a small fraction of the cost.

Comment Re:Translation (Score 2) 126

" is the very limited mass that can be launched today."
Not to mention the limited sizes - the James Webb Space Telescope had to partially "fold" its mirror (on the "wing" mirror subassemblies).
While launching a large, single piece mirror might not be possible due to launch stresses, the largest optical mirrors for telescopes have 8.2 meters diameter.
This is larger than the 4.5 meters of the Space Shuttle cargo bay diameter, 5.2 meters of the Falcon Heavy, 5.4 meters of Ariane 5, 5 meters of Delta IV heavy, ...
Also, that is a reason for the "inflatable space habitat" - tubes 4,39 meters in diameter as on the ISS aren't great living spaces

Comment Re:Wait for it (Score 1) 48

A lot of the Russian army is:
-navy in the Atlantic and Pacific oceans. They can't contribute much
-nuclear forces. Hopefully they won't contribute much
-if you think the Russian-Ukrainian border large (2300 km), Russia has almost twice that length bordering China (4300 km). And some 3400 km border to Mongolia, and a mind-boggling 7600 km border to Kazakhstan.
-not to mention all that northern sea border (7000+ km) where NATO infiltrators could invade.
-the United States have already taken Alaska from the Soviet Union, and who's to tell the invasion won't continue? You might have a short memory, but the Russian people regard the invasions of 1867 as yesterday.
-also, Russia needs to keep in reserve contingents for the liberation of the other Slavs (Bulgarians, Serbs) from the shackles of capitalism.

Comment Re:No (Score 1) 160

Eastern Europe has _a lot_ of Communist-era habitation spaces. There was a _lot_ of forced (and unforced) urbanization, so most of the current houses are built in Communist times.
Of villages, some were lost entirely (bulldozed down), others are just shallow husks of themselves. Few had the capacity to grow, and most of them have houses also built during the Communist era (with some built afterwards - proximity to big cities bringing investment in houses and condominiums).

Also, the second World War was not an advantageous era for buildings.

As for "the oldest housing stock in Europe"... not really. There are many decrepit houses, but not many that are truly old.

Comment Re:OK, but (Score 1) 104

The launch is on an eastward trajectory from Mahia Launch Complex.
Not many fresh water lakes eastward of New Zealand...

If they do polar launches then the launch trajectory is either southward or northward, with a small component westward. In any way, the launch trajectory avoids inhabited places.

SpaceX is not launching from Florida (the classical launch place for the USA missions, Apollo, Space Shuttle, ...). Even so, they have the Gulf of Mexico eastward of their launch platforms.

Comment Re:But this one weird trick... just use a boat? (Score 3, Interesting) 104

I'm not saying that a drone ship (barge, whatever) doesn't have large advantages.
However, the landing of the first stage is some 600km eastward.
With a helicopter, you fly three hours to there, you recover the stage and fly three hours back. Total cost: preparation, money for eventual delayed launches and 7 hours of flight time.
Meanwhile, you basically need to own the barge and ensure towing (with a towboat, a remote team to secure the booster after landing), ... The barge and towboat need to be away for at least two days, more probably 3. Also, towboats don't have much space for anything other than its crew so you might need a second ship for the "away" team.

So, a drone ship also costs you a lot. Whether it is cheaper is unclear, but - at least as a showpiece - catching the first stage from air by helicopter beats even unsuccessful recoveries on droneships (barges).

Comment Re: OK, but (Score 2) 104

The parachute is also "dead mass" in relation to the launch mass fraction.
I can't say if the parachute "dead mass" is eating more into the fuel budget than a propulsive landing would (remember that SpaceX had to quadruple the reserve of hydraulic fluid for landing operations, so another extra mass there).

The big advantage is that you can actually use all the fuel for propulsion in case of a "marginal" launch (with one or two broken engines out of 9), or you can launch more mass if you don't need to recover the stage. A parachute is dead mass (well, you can launch without it, but that will help only with prior warning).

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