Question about upcoming night launch for Shuttle

[Leovinus]

They're talking about having a night launch for next shuttle flight since they're confident that they've worked out the foam issues. Question: Launching at night means we won't see the tank in daylight. However, I assume they still have the on-tank camera and will still use it. The last time I saw a night launch the solids lit up the coast like daylight. I have to assume that there will still be illumination for the tank camera at least during the solid boost phase. Anybody have a clue on this? Also, how much light do you think we'd get from the main engines after the solids separate. Finally, given the time that the launch is scheduled, will there be any chance that the tank and shuttle will emerge into daylight together after separation while they're still close enough to get pictures? <div class="Discussion_UserSignature"> </div>

 

[Leovinus]

When I watched the shuttle on a night launch, the SSMEs were indeed very very bright. I followed the shuttle almost all the way down to the sea horizon. <div class="Discussion_UserSignature"> </div>

 

[Leovinus]

Here is a photo of an SSME lit. <br /><br />Edit: Picture from epower-propulsion.com <div class="Discussion_UserSignature"> </div>

 

[Leovinus]

Well when I looked at the launch from the ground, I was looking up at the business end of these engines and I saw plenty of light. The ET cam does not have this advantage. <br /><br />I have observed a growing plume from the ET cam well after sep. It grows with the thinning atmosphere. It is possible that this plume could reflect some of the engine light. <div class="Discussion_UserSignature"> </div>

 

[erioladastra]

"Launching at night means we won't see the tank in daylight."<br /><br />True - but keep in mind that the cameras are mainly to ascertain the improvements in tank foam. They also help the teams figure out possible places to focus inspections. The real inspection is done with the OBSS sensors on orbit. This is far better or more useful.

 

[brandbll]

Why not just paint all the foam glow in the dark? <div class="Discussion_UserSignature"> <p><font size="3">You wanna talk some jive? I'll talk some jive. I'll talk some jive like you've never heard!</font></p> </div>

 

[Leovinus]

I think seeing a piece come off the tank would be an additional piece of information. If they find a hole in the shuttle in orbit, they don't know if it was a bird, a chunk of ice, or a chunk of foam. Not that it makes any difference to the hole of course... <div class="Discussion_UserSignature"> </div>

 

[earth_bound_misfit]

How about swapping or modding the cameras for Infrared or even night vision? I suppose there must be good reasons for not doing this. <div class="Discussion_UserSignature"> <p> </p><p> </p><p>----------------------------------------------------------------- </p><p>Wanna see this site looking like the old SDC uplink?</p><p>Go here to see how: <strong>SDC Eye saver </strong>  </p> </div>

 

[Leovinus]

Well, the tank is very very cold. Not sure what infra-red would buy you. <div class="Discussion_UserSignature"> </div>

 

[mrmorris]

IR cameras are useful for identifying differences in temperatures, just as visible light cameras are useful for identifying differences in light (generally color). The only way an IR camera would be useful in identifying foam shedding would be if the foam pieces shed were a significantly different temperature than the temperatures of the objects around it. Since shedding foam pieces will be rushing past a background of more foam -- it's unlikely they would provide a reasonable contrast for IR imaging. Mind you -- the 'holes' where the foam was shed from might show up on IR, as they'd be showing a deeper (and presumably colder) level of the insulation. This isn't really the point of the cameras, however.<br /><br />Light amplification is more promising. However, anyone who has ever used LA devices will tell you that they don't give you nearly the level of discrimination as you'd like to have. Mind you -- I haven't used a pair of LA goggles for about ten years, so the technology might be heads & shoulders above what I used.<br /><br />If they are going to try to use low-light imaging, they'd do well give the areas of particular concern (e.g. the ice ramps) a light coat of paint in a high-contrast color (probably white) to make both the areas where foam has shed and tumbling foam objects more visible (i.e. while tumbling they're likely give a 'strobe' effect as the painted and unpainted sides point to the camera).

 

[sprockit]

Shuttle_Guy and I had an exchange a few years back on the visual characteristics of a night launch. I can state from first hand observation that the SSMEs, either through their heated engine bells or through exhaust emit a light, that from my location, is orange in color (probably due to sigting through the atmosphere), and actually pulse in brightness at a random frequency. I am up in the NE, north of Boston on the coastline, and can see the shuttle rise over the horizon approximately 7 minutes into the flight and watch it through MECO. We have observed it through mounted telescopes. Given it's azmuth, the shuttle's speed is very pronounced. I hope to video one of these observations before the close of the program!

 

[sprockit]

No, the oragnge pulsing is during the powered ascent phase well before ET sep. As I mentioned, I can see this right up to MECO. MECO occurs SSE from my observation point. I have had 3 urestricted launches and one w/cloudy skies. The mid winter observations are the best because, as SG stated, total darkness, no daylight and crisp, clean air for viewing. I agree that the brightness is about the same as landing lights. As previously mentioned, the most prominent thing is the speed in which it is moving. The shuttle is hauling, you know what, and it is quite evident. After it is out of sight I just marvel that people are traveling in that craft. I know that there are a lot of shuttle detractors on this message board and many of the points that have been made are accurate: cost of operation, reliability, purpose, etc. However the shuttle represents incredible technology (granted, old today) that the CEV will not surpass, even if its missions (if they ever happen) will bring back exploration.

 

[bpcooper]

There is a flame, but sg is partially correct. While the flame does remain visible (and I too have seen it from the NE), you can see on ET cams, and more prominantly on Delta 2 cams, that as the atmospheric pressure goes down at high altitude the flame and exhaust spread out.<br /><br />But, there is a visible flame, much the way the Delta 4 medium appears. The light of the SRBs drowns it out at launch, but if you look in most photos (from the side especially) you can make out the flames from all three engines separately. They extend down a good 500 feet at launch time.<br /><br />As for the camera visibility, it will be high contrast and washed out. Unlike the eye, a camera does not have the ability to stop down enough for the SRBs and still see the well-lit ET. They tried onboard cams on a few nighttime Delta 2s with limited success.<br /><br />One thing they do have is radar that can detect foam chunks coming off. It was tested starting with the MESSENGER launch in 2004 and has proven worthy. <div class="Discussion_UserSignature"> <p>-Ben</p> </div>

 

[bpcooper]

Hmm, not quite sure. Here is the track:<br /><br />http://satobs.org/image/ststrac1b.jpg <div class="Discussion_UserSignature"> <p>-Ben</p> </div>

 

[bpcooper]

I too, by the way, have seen the apparent flicker of the engines in the final 30 seconds before MECO. Same thing everytime that I saw it from NYC, which was at least four times. <div class="Discussion_UserSignature"> <p>-Ben</p> </div>

 

[SpaceKiwi]

<blockquote><font class="small">In reply to:</font><hr /><p>No, the Dec 7th launch which is about 10 hours before sun rise which equates to entering the sun light about 150 deg. to the east. The ET sep will be in darkness.<p><hr /></p></p></blockquote><br />The 'original' window (with fully lit ascent) was a couple of days at the end finishing on Dec 26, correct? Assuming the launch gets pushed deeper into the new window, say in the 15th-23rd time frame, will you get partially lighted conditions? If yes, at the ET Sep end of ascent or at the T-0 end, or is it not as simple a proposition as that? <div class="Discussion_UserSignature"> <p><em><font size="2" color="#ff0000">Who is this superhero?  Henry, the mild-mannered janitor ... could be!</font></em></p><p><em><font size="2">-------------------------------------------------------------------------------------------</font></em></p><p><font size="5">Bring Back The Black!</font></p> </div>

 

[drwayne]

I saw an article in Av Week that indicated that NASA was going to try and change the timing of a ground firing of an SRB to get some better data on the visible output of an SRB plume.<br /><br />I found that fascinating when I read it....<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[erioladastra]

"They're talking about having a night launch for next shuttle flight "<br /><br />This was approved today by the way.

 

[bobw]

I know this is a pretty old thread but yesterday's launch of ISS 12A.1/ STS-116 has shed some new light on the subject.<br /><br />I read that they got some data from a static firing, referenced in drwayne's post second above this, that showed a camera could work. <br /><br />At yesterdays news conference they said that they did see some small pieces, shilouetted against the rocket flames, come off. John Shannon said at ET separation the attitude control firings light up the tank and that in the future they may use them purposely to illuminate the tank for pictures from the belly cam during night launches. He made motions with his hands like they were going to light up the thrusters and just fly forward over the tank taking pictures along the way.<br /><br />This is such an interesting topic I had to bump it up for new insights. <div class="Discussion_UserSignature"> </div>

 

[Leovinus]

You saved me the trouble of hunting for this thread. <div class="Discussion_UserSignature"> </div>

 

[bobw]

I managed to see the briefing again late last night. His comments were in response to a reporter's question about the camera views "Were you surprised by what you saw?" He said he was surprised in a good way and that they didn't try to get photos of the tank because they didn't think there would be any light. While he was talking about firing the thrusters for illumination and demonstrating with his hands he said something pretty close to 'do the same maneuver we did on the earlier flights'. It sounded like he expects to get some pretty good photos of the tank.<br /><br />I don't know exactly what that maneuver was but his hands did indicate that the orbiter would sort of fly along with the tank. It was most likely a gross oversimplification for the press and for people like me. <div class="Discussion_UserSignature"> </div>