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14 minutes ago, sh1pman said:

Well, I can only see the brightest stars from where I live, like Altair, etc. Terrible light pollution... 

Yeah,  this townhouse complex isn't very dim either

22 minutes ago, tater said:

Checks watch.... Oh hey, it's a clear night and there's a pass in 22 minutes! Sweet! Good time to take the dog for a walk, or vice versa!

Edited by StrandedonEarth
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1 hour ago, StrandedonEarth said:

I know there's a website to tell when it's visible, but I haven't used it in awhile. I need one that'll text me!

There is also https://transit-finder.com/.

It can be interesting if you want to observe and/or picture it while it is transiting in front of the moon or the Sun (or when passing close-by). Just enter your coordinates and it will load different locations from where you could spot it.

---

To stay on the topic:

 

Another nice video of the Adventures of B1050.

Edited by XB-70A
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1 hour ago, StrandedonEarth said:

Checks watch.... Oh hey, it's a clear night and there's a pass in 22 minutes! Sweet! Good time to take the dog for a walk, or vice versa!

That worked well, I was able to spot Dragon chasing the ISS before the freezing-rain clouds moved in. It was farther behind than I expected, the other chaeses I've seen were closer together.

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16 hours ago, CatastrophicFailure said:

I would think the alloys used would give some degree of corrosion protection, since they have to deal with very high temps and exposure to LOX and combustion.

Not likely. Two utterly distinct forms of corrosion involved; hot seawater adds the potential for such things as galvanic corrosion between the steel outer wall and the copper inner wall of the engine bell.

It can get pretty bad: https://www.wired.com/2011/06/shipbuilder-blames-navy-as-brand-new-warship-disintegrates/

Edited by DDE
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1 hour ago, DDE said:

One of the worst point about the Independence-class being that... a similar problem happened earlier on some units from the San Antonio-class LPDs (it was more than ten years ago, I guess it has been resolved since).

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That signature is ... distracting when typing :-)

------------

Aluminum corrodes in seawater only when there is a current, but then aggressively. Aluminum is pretty far up in the galvanic row, zinc and magnesium are "better", that is why they are frequently used as sacrificial anodes. More resistant conducting materials otoh must be thoroughly isolated from the hull. Apart from galvanic corrosion, aluminum is a superb shipbuilding material because it passivates itself, other than steel which slowly rots away. A nicely built aluminum boat will last longer than a lifetime. It is the second best material for sturdy sailing boats on the ocean, after epoxy resin.

Causes for electric currents on a ship are manifold of course, the source doesn't even have to be on the same ship, the neighbour berth in a harbour can be the culprit and source of a current in the basin, or loose cables on the seafloor. But if it corrodes around the engines like the link states then chances are that these have not been isolated properly from the hull and there is a constant current between the aluminum hull and the steel engines, making the hull loose mass. If i was the customer i'd know whom to blame :-/.

 

The booster will probably just corrode chemically in the seawater. Especially filigree metal parts and ducts, screws and things are in danger of building up a rust layer, even from atmospheric dust particles, though two days are a short time. Most fibre plastics, if they aren't specially coated, are damaged if they have microscopic cracks where seawater can enter inside of the lamination. The booster lay several days in the water, so it is probably not suitable for a fourth flight any more.

 

Edited by Green Baron
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2 hours ago, DDE said:

Not likely. Two utterly distinct forms of corrosion involved; hot seawater adds the potential for such things as galvanic corrosion between the steel outer wall and the copper inner wall of the engine bell.

It can get pretty bad: https://www.wired.com/2011/06/shipbuilder-blames-navy-as-brand-new-warship-disintegrates/

Fixed.

5XuRk7L.jpg

I'm sure I just confused the heck out of a lot of people, but if you aren't keeping up with the latest Wintergatan Wednesdays, that's your problem, not mine.

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1 minute ago, ThatGuyWithALongUsername said:

Fixed.

5XuRk7L.jpg

I'm sure I just confused the heck out of a lot of people, but if you aren't keeping up with the latest Wintergatan Wednesdays, that's your problem, not mine.

Ah, so Martin found a large-scale buyer! Breaking news, SpaceX abandons barge based recovery in favor of splashdowns and galvanic corrosion resistant T-shirts...

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2 hours ago, Green Baron said:

The booster lay several days in the water, so it is probably not suitable for a fourth flight any more.

This was its first flight. ;) That booster is on the other coast, and probably is on its way to a fourth flight. 

 

6 hours ago, kerbiloid said:

Just read that Dragon has been caught by Canadarm-2 for berthing.

Is there a picture of the handle/port/thing to be grabbed by Canadarm? How and where does it hold the Dragon?

SpaceX_Dragon_C2+_approaching_ISS_(ISS03

i forget the technical term but it’s basically an avionics bay, too, full of all sorts of sensors and navigation equipment that flips open just after separation. 

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33 minutes ago, CatastrophicFailure said:

i forget the technical term but it’s basically an avionics bay, too, full of all sorts of sensors and navigation equipment that flips open just after separation

Its called the GNC (Guidance Navigation Control) bay. :)

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1 hour ago, CatastrophicFailure said:

i forget the technical term but it’s basically an avionics bay, too, full of all sorts of sensors and navigation equipment that flips open just after separation. 

Thanks. I have seen this thing alone but didn't realize, how do they place it in place.

Edited by kerbiloid
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Pro: Reduced Dev time, better understood materials, possibly cheaper construction, maybe better radiation protection. Depending on the metal, they might be able to get away with using the hull as a heat shield.

Con: Heavy, either reduced payload (AGAIN!) or a much larger rocket, reduced benefit from orbital refueling, possibly less cool. And all of the current infrastructure must be scrapped.

 

If it gets BFR on the table earlier for cheaper, then yay, but if they match the size of the old BFR then they only have FH levels of payload, but if they go back up to 150t payload then they will have a huge rocket, which is great because it looks cool, but would be even harder to build.

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