7 ms·

"Hold. Hold. Hold. Weather is no go" @ 4:31pm EST

by nacs 12y ago

ceejayoz 12y ago
And because this is an instantaneous launch window, that means no launch today.
Laremere 12y ago
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.
- baggers 12y ago
  http://en.wikipedia.org/wiki/Launch_commit_criteria#Falcon_9 http://en.wikipedia.org/wiki/Launch_commit_criteria#Falcon_9 within 19 kilometres (10 nmi) of an attached thunderstorm anvil cloud.
- swhitt 12y ago
  > 1 second launch window Why is it so precise?
  - JshWright 12y ago
    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.
    - rgbrenner 12y ago
      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.
      - ohazi 12y ago
        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.
  - trose 12y ago
    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.
cryptoz 12y ago
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?
- ceejayoz 12y ago
  A forecast doesn't stop a popup thunderstorm from entering the no-go zone.
  - cryptoz 12y ago
    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?
    - ceejayoz 12y ago
      > 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.
      - cryptoz 12y ago
        > 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?
mbreese 12y ago
That's a tough time to abort too... T-3:07. Hopefully the weather gods are more forgiving tomorrow.
kirankoduru 12y ago
so close
725686 12y ago
How come that on t minus 3min there is a weather no go? Anyone knows how this works...
- ceejayoz 12y ago
  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.
- gk1 12y ago
  Here's more info about the Anvil Rule for launches and why it causes a NO-GO: http://weather.about.com/od/thunderstormsandlightning/f/anvilrule.htm http://weather.about.com/od/thunderstormsandlightning/f/anvi...
- deleted 12y ago
  [deleted]
- 725686 12y ago
  But they where waiting for the last minute for weather to clear, or was it that just then the no-go condition generated?
Lx1oG-AWb6h_ZG0 12y ago
> Launch postponed due to lightning from an approaching anvil cloud (https://twitter.com/elonmusk/status/587715056432889856 https://twitter.com/elonmusk/status/587715056432889856) Anyone know how they detect lightnings? Is it just cameras, or do they have planes flying around?
- sfeng 12y ago
  You can detect lightening using ground based detectors: http://en.wikipedia.org/wiki/Convective_storm_detection#Lightning_detection 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.
- fake-name 12y ago
  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 http://en.wikipedia.org/wiki/Lightning_detection
- flowless 12y ago
  Antennas, see https://en.wikipedia.org/wiki/Lightning_detection https://en.wikipedia.org/wiki/Lightning_detection
- peterwaller 12y ago
  Here's a link to a live Live lightning map: http://www.blitzortung.org/Webpages/index.php?lang=en http://www.blitzortung.org/Webpages/index.php?lang=en
- jewel 12y ago
  Lightning can be detected from thousands of miles away. See http://www.blitzortung.org/Webpages/index.php?lang=en&page_0=30 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.

"Hold. Hold. Hold. Weather is no go" @ 4:31pm EST

by nacs 12y ago

"Hold. Hold. Hold. Weather is no go" @ 4:31pm EST

ceejayoz 12y ago

And because this is an instantaneous launch window, that means no launch today.

Laremere 12y ago

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.

baggers 12y ago
http://en.wikipedia.org/wiki/Launch_commit_criteria#Falcon_9 http://en.wikipedia.org/wiki/Launch_commit_criteria#Falcon_9 within 19 kilometres (10 nmi) of an attached thunderstorm anvil cloud.
swhitt 12y ago
> 1 second launch window Why is it so precise?
- JshWright 12y ago
  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.
  - rgbrenner 12y ago
    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.
    - ohazi 12y ago
      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.
- trose 12y ago
  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.

cryptoz 12y ago

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?

ceejayoz 12y ago
A forecast doesn't stop a popup thunderstorm from entering the no-go zone.
- cryptoz 12y ago
  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?
  - ceejayoz 12y ago
    > 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.
    - cryptoz 12y ago
      > 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?

mbreese 12y ago

That's a tough time to abort too... T-3:07. Hopefully the weather gods are more forgiving tomorrow.

kirankoduru 12y ago

so close

725686 12y ago

How come that on t minus 3min there is a weather no go? Anyone knows how this works...

ceejayoz 12y ago
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.
gk1 12y ago
Here's more info about the Anvil Rule for launches and why it causes a NO-GO: http://weather.about.com/od/thunderstormsandlightning/f/anvilrule.htm http://weather.about.com/od/thunderstormsandlightning/f/anvi...
deleted 12y ago
[deleted]
725686 12y ago
But they where waiting for the last minute for weather to clear, or was it that just then the no-go condition generated?

Lx1oG-AWb6h_ZG0 12y ago

> Launch postponed due to lightning from an approaching anvil cloud (https://twitter.com/elonmusk/status/587715056432889856 https://twitter.com/elonmusk/status/587715056432889856) Anyone know how they detect lightnings? Is it just cameras, or do they have planes flying around?

sfeng 12y ago
You can detect lightening using ground based detectors: http://en.wikipedia.org/wiki/Convective_storm_detection#Lightning_detection 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.
fake-name 12y ago
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 http://en.wikipedia.org/wiki/Lightning_detection
flowless 12y ago
Antennas, see https://en.wikipedia.org/wiki/Lightning_detection https://en.wikipedia.org/wiki/Lightning_detection
peterwaller 12y ago
Here's a link to a live Live lightning map: http://www.blitzortung.org/Webpages/index.php?lang=en http://www.blitzortung.org/Webpages/index.php?lang=en
jewel 12y ago
Lightning can be detected from thousands of miles away. See http://www.blitzortung.org/Webpages/index.php?lang=en&page_0=30 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.