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Oh boy the ISS crew must be pretty lonely up there The Zero-G indicator is doing well in the ISS it seems!

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Looks like the ISS is over my horizon from 8:35 Eastern to 8:41 Eastern and climbs up to 29 degrees. So I have a pretty good shot from my skyscraper.

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1 hour ago, Ultimate Steve said:
ISS (ZARYA) Fri, 08 Mar 2019 07:30:10 07:35:31 07:40:53 07:35:31 Shadow 76.8 11.4 No

 

Maybe a re-entry trail? I don't know how long or bright they are, they probably wouldn't stretch all the way to Iowa. And it also might be cloudy.

¯\_(ツ)_/¯

The best answer I can give you is "maybe bright enough". I think I'll get up and go out to at least watch NASATV from a particular building that has big windows in the right direction, so I can go outside if there's a good chance I'll be able to see or hear it.

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Elon has made several statements about tumble risk associated with Dragon 2's asymmetric backshell.

What are the actual risks here?

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41 minutes ago, sevenperforce said:

What are the actual risks here?

He said it can cause roll instability on reentry. Which can probably lead to RUD.

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1 hour ago, sh1pman said:

He said it can cause roll instability on reentry. Which can probably lead to RUD.

I don't know if loss of roll authority would RUD or just lead to unacceptably high gee-loading.

Dragon 2 has a ballast sled which can be used to adjust CoM and thus produce lifting re-entry. However, it needs roll authority to work; without roll authority you can't use the ballast sled because you'll get precession around the longitudinal axis, and so you end up with ballistic entry. That might be the main pucker factor here.

If lifting-body entry fails and you get a ballistic entry, I wonder...is there a chance of coming down over a populated area?

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1 hour ago, sevenperforce said:

If lifting-body entry fails and you get a ballistic entry, I wonder...is there a chance of coming down over a populated area?

The unnervingly frequent cases of the Soyuz entering hatch-first (e.g. -5, TMA-11) indicate an uncertainty of 420-600 km of undershoot, possibly worse for the slightly wider heat shield of the Dragon.

If I’m eyballing the map right (based on distance from Kostanai to Zhezkagany), an MMH/NTO-fuelled spaceship might come down west of Jacksonville.

This is unexpectedly risky for NASA.

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They are apparently building a Star Hopper transporter right now.

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Posted (edited)

I'm back from my Florida trip, so here are some higher resolution images of some photos I took.

We took a bus tour of KSC, but we couldn't get close to LC39A...because the Falcon 9 DM-1 was sitting on it getting ready to fly the next morning (at 3:49 AM)...

FkfJQ8D.jpg

We also took another bus tour of Cape Canaveral Air Force Station a couple days later and saw the Delta 4 getting readied for its upcoming flight..

hpB5MlS.jpg

We watched the launch of the Falcon 9 from 14.6 miles away at our hotel in Port Canaveral (since we had to be up early that same morning to go to meetings, we couldn't take the extra time to try to watch it from closer). Below is a picture of the Falcon 9 (200mm lens on my Nikon D90) clearing the foreground buildings...

oXaM6SI.jpg

And here is a shot of the people watching the launch from the parking lot...

mpHZaVk.jpg

These next shots were when the Falcon was high in the sky. The sound of the launch reached us about 75 seconds after liftoff.

3Qypmcc.jpg

We were also able to see the entry burn far down range. The picture below shows the burn...which isn't too impressive, but I was pleased to be able to see it at all. We could not see the landing burn, which was off over the horizon.

IPiIUzw.jpg

We happened to be staying around in the Port Canaveral area for a few extra days, so we were still there when the Falcon 9 booster came back into port. You can view the arrival and handling of the booster from parking lots on the south side of the barge canal (the Falcon is docked on the north side of the canal). Here is a wide shot that shows the booster on the barge (Mr. Steven, without any arms installed, is off to the left). After the Falcon booster is swung onto shore with the crane, it is set onto a stand that I marked with a yellow arrow.

kA81Chs.jpg

Photo of the booster on the barge below. The Octograbber is still attached to the booster (the white arms grabbing it from the bottom)...

TkHACwO.jpg

The crane positioning the top cap in place. Nobody was up there guiding or connecting anything, so it apparently grabs on just fine remotely controlled.

aNOK7UW.jpg

Close-up of the workers around the base of the rocket. The Octograbber has been detached and moved off to the left.

DLh6Yxe.jpg

When I returned later, the crane had lifted the booster off the barge and onto the pedestal on the right...

vIxKGvS.jpg

You can drive around to the north side of the barge canal, but you can only drive in so close to the booster before there are fences and guard stations. The picture below is from that side, with the booster sitting on the pedestal...

EYUPyvb.jpg

And here's a closeup of the top of the booster from that side...

AEy0NN8.jpg

 

 

Edited by Brotoro

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13 hours ago, sevenperforce said:

I don't know if loss of roll authority would RUD or just lead to unacceptably high gee-loading.

Every crewed spacecraft since Gemini and Soyuz has used a lifting reentry and needs roll authority.  Except for the Shuttle, they all had a reentry RCS system that was only used for just before and during reentry.  Gemini 8 (Neil Armstrong and David Scott) used their reentry RCS to stabilize after a jet jammed open on their orbital RCS; because of that, the flight needed to be finished up pronto as it was specified to reenter within a certain time of its activation just to have positive control.  And they all, including the Shuttle, have multiple redundant RCS jets.

Lifting reentries reduce the G-loads on the crew significantly.  Loss of roll authority would be bad for the crew both for the increased G-loads and error in landing location.  I don't think there would be lost of the craft (certainly not for Apollo which turned out to have a heatshield 3 times over even engineering margin on what was needed for Lunar return) but the crew would really be worse for it.

 

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Undocking.

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Im going to depart from my home to school at nearly the same time Dragon 2 will depart from the ISS, so i can't watch it.

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Dragon otw home. Reentry burn in a few hours. I'll be asleep I think.

Strike that, I should be up. 8:45 Eastern, that's only 6:45 here, an hour after our alarm goes off.

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Spoiler

Will they first check it for the extraterrestrial lifeforms?

There is Ripley, after all.

 

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According to the BBC, Dragon sports a fetchingly bushy orange moustache during reentry.

https://www.bbc.co.uk/news/science-environment-47477617

Not long to go now. Hopefully Elon’s fretting over roll control will come to naught. *touches wood*

 

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1 minute ago, Flying dutchman said:

I think the radio hosts got it wrong.

Its going to deorbit in about 40 minutes and should splash down around 90 minutes from now

 

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