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Re:SpaceX CRS-6 Launch Webcast by nacs on Monday April 13, 2015 @04:30PM (#9370249)
"Hold. Hold. Hold. Weather is no go" @ 4:31pm EST
Re:SpaceX CRS-6 Launch Webcast by Laremere on Monday April 13, 2015 @04:31PM (#9370266)
Specifically, there's thunderheads within their no-go radius, so weather called hold. Since it's only a 1 second launch window, there won't be a launch today.

Edit: Next launch window is tomorrow at 4:10pm eastern time. However the weather outlook isn't much better.

Re:SpaceX CRS-6 Launch Webcast by baggers on Monday April 13, 2015 @05:30PM (#9370638)
http://en.wikipedia.org/wiki/Launch_commit_criteria#Falcon_9 within 19 kilometres (10 nmi) of an attached thunderstorm anvil cloud.
Re:SpaceX CRS-6 Launch Webcast by swhitt on Monday April 13, 2015 @05:40PM (#9370686)
> 1 second launch window

Why is it so precise?

Re:SpaceX CRS-6 Launch Webcast by trose on Monday April 13, 2015 @06:02PM (#9370804)
While it's possible to inject the dragon capsule anywhere and get it's orbit in line with the ISS, its much more economical to inject it really close to the ISS so they dont need to do as much work to finish the trip.
Re:SpaceX CRS-6 Launch Webcast by JshWright on Monday April 13, 2015 @05:56PM (#9370775)
They need to launch when the orbital plane of the station is directly overhead. The earth rotates surprisingly quickly, so even a minute or two later the plane of Dragon's orbit would be far enough off from the plane of the station that a couple expensive inclination change maneuvers would be necessary to line them up again.
Re:SpaceX CRS-6 Launch Webcast by rgbrenner on Monday April 13, 2015 @06:35PM (#9370968)
The earth rotates surprisingly quickly

Not so much the earth as ISS.

The earth rotates at 24900mi/day or about 1040mph.

The ISS, to maintain its orbit, travels at 17150mph or about 5 miles per second.

So in two minutes, it travels about 600 miles.

Re:SpaceX CRS-6 Launch Webcast by ohazi on Monday April 13, 2015 @06:50PM (#9371043)
Yeah, but the window is short because you have to catch the orbital plane, not the ISS itself. Earth's rotation speed is the relevant number here for figuring out how fast that plane sweeps across the sky.
Re:SpaceX CRS-6 Launch Webcast by ceejayoz on Monday April 13, 2015 @04:31PM (#9370257)
And because this is an instantaneous launch window, that means no launch today.
Re:SpaceX CRS-6 Launch Webcast by Lx1oG-AWb6h_ZG0 on Monday April 13, 2015 @04:35PM (#9370293)
> Launch postponed due to lightning from an approaching anvil cloud (https://twitter.com/elonmusk/status/587715056432889856)

Anyone know how they detect lightnings? Is it just cameras, or do they have planes flying around?

Re:SpaceX CRS-6 Launch Webcast by jewel on Monday April 13, 2015 @04:43PM (#9370353)
Lightning can be detected from thousands of miles away. See http://www.blitzortung.org/Webpages/index.php?lang=en&page_0.... Turn on "detectors" on the right to see the distances involved.

That site works by a using a network of cheap EMP detectors. It uses the timing differences from each sensor to trilaterate the position of the lightning strike.

Re:SpaceX CRS-6 Launch Webcast by whoisthemachine on Monday April 13, 2015 @05:04PM (#9370494)
That's a nifty website!
Re:SpaceX CRS-6 Launch Webcast by flowless on Monday April 13, 2015 @04:41PM (#9370341)
Re:SpaceX CRS-6 Launch Webcast by sfeng on Monday April 13, 2015 @04:39PM (#9370331)
You can detect lightening using ground based detectors: http://en.wikipedia.org/wiki/Convective_storm_detection#Ligh...

This specific delay though was caused by convective clouds being too close to the launch. This was probably determined with either ground based radar, or visible/IR images from satellites.

Re:SpaceX CRS-6 Launch Webcast by fake-name on Monday April 13, 2015 @04:40PM (#9370336)
Using radio, presumably.

There is a considerable body of research on detecting the presence and range of lightning: http://en.wikipedia.org/wiki/Lightning_detection

Re:SpaceX CRS-6 Launch Webcast by peterwaller on Monday April 13, 2015 @04:42PM (#9370344)
Here's a link to a live Live lightning map: http://www.blitzortung.org/Webpages/index.php?lang=en
Re:SpaceX CRS-6 Launch Webcast by cryptoz on Monday April 13, 2015 @04:31PM (#9370267)
If only there were someone working on high-accuracy weather forecast systems for convective systems using existing cheap networked sensors ;). I would love to know how much money I could save SpaceX by providing this forecast more accurately with much more lead time.

What is the cost to scrub a launch due to the weather at the last minute?

Re:SpaceX CRS-6 Launch Webcast by Animats on Monday April 13, 2015 @04:52PM (#9370416)
There's plenty of weather data for that area.[1] That's the world's most heavily instrumented area for weather.[2] A huge amount of effort goes into predicting lightning hazards. There are electrostatic field measuring devices for miles around to give warning of pre-lightning conditions.

Right now, there is a major thunderstorm system north of the launch area, and a smaller one south of it. They were trying to launch through the gap.

[1] http://www.accuweather.com/en/us/cape-canaveral-fl/32920/wea... [2] http://commons.erau.edu/cgi/viewcontent.cgi?filename=4&artic...

Re:SpaceX CRS-6 Launch Webcast by andor436 on Monday April 13, 2015 @05:00PM (#9370464)
How are you going to sense thunderstorms with a smartphone? Temperature / Barometric pressure changes? User input? Weather Underground has been doing the latter for a couple of years, although it doesn't seem to be altering their "current conditions" reporting yet: http://www.wunderground.com/about/pr/news.asp?date=20131121

It's a great idea - I think there are a bunch of similar applications that could leverage phones like this.

Re:SpaceX CRS-6 Launch Webcast by cryptoz on Monday April 13, 2015 @05:07PM (#9370516)
Thanks - I have about 400,000 barometers connected globally right now. Our data archive is about 1.5B measurements, we're getting about 5M per day. We will use this as the primary new input to WRF model runs, outputting high-res forecasts. The network I run is called PressureNet, you can see our website at http://pressurenet.io or have a look at our flagship Android app: https://play.google.com/store/apps/details?id=ca.cumulonimbu...

Early initial targets are large convective systems (like these) that are difficult to predict. Our dense barometer network should resolve them far better than other existing networks.

We also do Current Conditions like WU, but that idea needs a lot of work before anyone makes a valuable product on it alone. Typically those readings are used to validate and tweak models, not make forecasts.

Other sensors that will prove useful: cell signal strength, thermometer, humidity, UV sensor, ambient light sensor, etc.

And yes, there are lots of other uses! Like earthquake mapping and alerting, I wrote a blog post mentioning some ideas and the importance for the code to be open source: http://www.jacobsheehy.com/2014/02/open-source-software-is-i...

Re:SpaceX CRS-6 Launch Webcast by ceejayoz on Monday April 13, 2015 @04:32PM (#9370273)
A forecast doesn't stop a popup thunderstorm from entering the no-go zone.
Re:SpaceX CRS-6 Launch Webcast by cryptoz on Monday April 13, 2015 @04:32PM (#9370277)
Of course not. But it would help SpaceX plan and prepare much more in advance than 3 minutes. There is certainly a cost associated with getting everything set up, and then postponing the launch. Could they have planned for this earlier and not got everything ready?
Re:SpaceX CRS-6 Launch Webcast by barkingcat on Monday April 13, 2015 @04:44PM (#9370361)
I think you're thinking about the problem the wrong way.

There is a cost to postponing the launch, but compared to having their rocket blown up by lightning on launch, it's nothing.

As far as I know, the budget for these launches already includes x number of retries - since scrubbing launches and retrying in another window is actually standard procedure - so they are not "loosing" as much money as you think. It's only if they exceed the # of retry attempts that they've budgeted for that a solution like yours becomes viable, and even then, you're not fighting against "the cost of getting things set up".

You're fighting against the cost of having their rocket blown up on launch because of bad or unforseen weather events. That's why they scrub - not because the weather is too bad to fly - it's because there could be an unforseen event happening because an anvil cloud (which has lightning in it) - merges with another large storm formation at 10 nm - basically, it's insurance against the rocket blowing up.

If you can insure your weather detection solution in the high hundreds of millions for a positive launch, then there would be a market for it.

And to be successful, your product will need to cut that 3 min downwards, not upwards.

So that mission control can have a better confidence of scrubbing a launch, say within 10-s of launch time vs 3 min.

You get what I mean? Better weather detection allows mission control to delay longer until the best guess estimate of when to hit the STOP button, not so that they can plan ahead to put a launch at xyz date/time because a weather prediction system says so.

Re:SpaceX CRS-6 Launch Webcast by ceejayoz on Monday April 13, 2015 @04:36PM (#9370303)
> Could they have planned for this earlier and not got everything ready?

Probably not. They were a go up until just three minutes before launch. I doubt any extant or near-future forecasting system is able to tell you that a specific storm cell will be in a specific spot at an exact minute all that far in advance.

Re:SpaceX CRS-6 Launch Webcast by cryptoz on Monday April 13, 2015 @04:38PM (#9370326)
> I doubt any extant or near-future forecasting system is able to tell you that a specific storm cell will be in a specific spot at an exact minute all that far in advance.

Well, this is exactly my plan, and I'm going to do it ASAP. Prototype should be done by summer. There are millions of little weather stations all over Florida that nobody is using (smartphones). By connecting those stations together and pulling the live sensor data into forecasts, I do in fact believe that these small thunderstorm cells should be very well-forecasted if we take in this dense dataset.

This forecast system doesn't exist yet, you're right. But it should exist in the next couple months/years, and when it does, it should be able to provide this kind of forecast.

BUT only if that is worth money to a group like SpaceX - is it? That's really my question. I know I can build the technology, but will anyone like SpaceX buy, and at what price?

Re:SpaceX CRS-6 Launch Webcast by mikeash on Monday April 13, 2015 @05:08PM (#9370523)
How accurate would it be? Even if you can predict with, say, 95% accuracy that a thunderstorm will cause a launch scrub, SpaceX might want to give it a try anyway in case that 5% comes true. They want to launch ASAP, and they'd look dumb if they called it off only to find that the weather was fine.

Accurate forecasts are no doubt extremely valuable in many cases, but for this specific case I don't see it changing much.

Re:SpaceX CRS-6 Launch Webcast by MichaelGG on Monday April 13, 2015 @04:53PM (#9370423)
What do cell phones have that are particularly useful to detect lightning? Or look at other sources for lightning, then thousands of barometers to predict movement?
Re:SpaceX CRS-6 Launch Webcast by ceejayoz on Tuesday April 14, 2015 @08:46AM (#9373740)
Cell phones aren't needed to detect lightning. It's the pressure measurements that are potentially valuable in making a more accurate map than can be gathered by scattered weather stations.

http://www.lightningmaps.org/realtime shows lightning in realtime as they're detected by stations across the planet. If you turn on the "stations" display, you can see detectors in Utah spotting lightning in the Gulf of Mexico.

Re:SpaceX CRS-6 Launch Webcast by th0br0 on Monday April 13, 2015 @04:47PM (#9370384)
To cryptoz (can't reply, probably too deep?): I was going to argue that it would be terrible difficult to build up that smartphone network. But then I saw that you do PressureNet (awesome tool btw!) and, oh well... looks like you've definitely got the network part done already.

OTOH, why not just ping @elonmusk on twitter?

Re:SpaceX CRS-6 Launch Webcast by cryptoz on Monday April 13, 2015 @06:41PM (#9371002)
Well thanks! But actually, building the network is indeed a big challenge. We've spent the better part of our 3 years just thinking and implementing methods to do it. We've arrived at an SDK model [1] where we work with app partners to integrate simple sensor code and contribute to our network. So we're able to grow quite quickly compared to a single app to download, but it's still not easy getting the necessary scale. We're aiming for about 10 million sensors, currently have 0.5 million. So we're getting there.

I've sent @elonmusk a few messages over the years but no replies so far. I am @vallesmarineris, so I think one day he'll notice that I already live on Mars and we'll chat.

[1]: https://github.com/Cbsoftware/pressureNET-SDK

Re:SpaceX CRS-6 Launch Webcast by sandstrom on Monday April 13, 2015 @05:48PM (#9370725)
preassurenet is cool!

It always reminds me about this interchange: https://news.ycombinator.com/item?id=8292091

Probably easier to google up someone on the launch team and ask them.

Re:SpaceX CRS-6 Launch Webcast by mbreese on Monday April 13, 2015 @04:32PM (#9370275)
That's a tough time to abort too... T-3:07.

Hopefully the weather gods are more forgiving tomorrow.

Re:SpaceX CRS-6 Launch Webcast by 725686 on Monday April 13, 2015 @04:33PM (#9370281)
How come that on t minus 3min there is a weather no go? Anyone knows how this works...
Re:SpaceX CRS-6 Launch Webcast by gk1 on Monday April 13, 2015 @04:35PM (#9370296)
Here's more info about the Anvil Rule for launches and why it causes a NO-GO: http://weather.about.com/od/thunderstormsandlightning/f/anvi...
Re:SpaceX CRS-6 Launch Webcast by ceejayoz on Monday April 13, 2015 @04:34PM (#9370287)
The launch is a no-go because an anvil cloud (thunderstorm) entered the 10 mile radius around the launch site. Prior to the scrub there were a few comments about a cloud being close to the exclusion zone but not yet in it.
Re:SpaceX CRS-6 Launch Webcast by 725686 on Monday April 13, 2015 @04:37PM (#9370321)
But they where waiting for the last minute for weather to clear, or was it that just then the no-go condition generated?
Re:SpaceX CRS-6 Launch Webcast by kirankoduru on Monday April 13, 2015 @04:32PM (#9370279)
so close