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NASA Space Technology

SpaceX Flies Satellites For Iridium, NASA In 10th Launch of 2018 ( 28

SpaceX launched a total of seven satellites for Iridium and NASA, reusing part of a previously flown rocket for its 10th mission of 2018. "Five Iridium NEXT satellites were launched as part of the company's campaign to replace the world's largest commercial satellite network," reports Bloomberg. "SpaceX's mission also includes launching twin satellites for the Gravity Recovery and Climate Experiment Follow-On (GRACE-FO)," which will "measure the distribution of the Earth's mass" and "monitor changes in ice sheets, glaciers and sea level." From the report: The Falcon 9 rocket lifted off from Vandenberg Air Force Base on California's central coast about 12:47 p.m. local time. The GRACE-FO satellites deployed roughly 11 minutes after launch, while the Iridium satellites are due to be released roughly an hour after the launch. SpaceX won't attempt to recover the first stage of the rocket, which flew in January during the Zuma mission, according to a SpaceX press kit. CBS News has some additional details about the GRACE-FO satellites. They were reportedly "designed to fly in tandem 137 miles apart in a 305-mile orbit around Earth's poles," reports CBS News. "Using a microwave tracking system, the distance between the two 1,300-pound satellites can be measured to within the diameter of a red blood cell. By precisely measuring the distance between the satellites, scientists can determine how much mass is below the flight path and then calculate the contribution of water, creating global maps every 30 days."

UPDATE: SpaceX has confirmed that all five Iridium satellites have been successfully deployed.
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SpaceX Flies Satellites For Iridium, NASA In 10th Launch of 2018

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  • by Zocalo ( 252965 ) on Tuesday May 22, 2018 @05:43PM (#56655680) Homepage
    Apparently these five art are part the next generation of Iridium satellites and they are not expected to create the same predictable flares [] as the previous generation did when their solar panels caught the sun at the right angle. As a result, another batch of the older Iridium satellites will be either moved to parking orbits that are not so tightly controlled with less predictable flares where they can act as backups, or possibly even de-orbited outright. Predictable Iridium Flares are currently expected to cease altogether [] by the end of the year, so last call, I guess...
    • Yes, I have been catching as many as I can while they last. Loved to show them to people, not many have ever noticed them. But then, there are people who never noticed Venus until you point it out to them.
    • I think I've inadvertently caught a few. Are they easily mistaken for a meteor, or is the apparent movement to slow?
      • Someone who doesn't know the difference could certainly mistake the two, but Iridium flares are MUCH slower. They last on the order of (5s-20s), and the brightness profile is a smooth fade-in, peak, fade-out rather than a meteor's quick rise and slower fade.

        This site [] will give you a prediction for your location of when you can see them.

    • It's not the solar panels that cause the flare, it's the radio dish.

  • Everything nominal, from employee sighs the fairing recovery attempt failed but they didn't show any of that so basically no progress just your bog standard satellite launch. I guess that's better for SpaceX than the alternative but the entertainment value was quite low.

  • The fit and finish was terrible. The keycard wasn't recognized, the backup camera didn't work, the audio system spontaneously turned itself on, and the passenger vanity mirror fell off. It's a TERRIBLE rocket! TERRIBLE! Nobody will ever buy them! Nobody SHOULD ever buy them! If you can't see behind you, how can you back your rocket up? And it's really embarrassing when you walk up to your rocket in the parking lot and the audio system starts blasting Yanni out the windows. Just because it put 7 sate

    • by Mal-2 ( 675116 )

      Actually, the rocket was blasting Laurel. You just heard Yanni because you were primed for it.

  • GRACE-FO (Score:4, Interesting)

    by riverat1 ( 1048260 ) on Tuesday May 22, 2018 @07:38PM (#56656238)

    For me the big news of this launch is the GRACE-FO satellites. The amount of and value of the information the original GRACE satellites provided is hard to overstate. Who knew that measuring the minute changes in gravity around the Earth would be so informative? The original GRACE satellites finally failed in October 2017 after 15+ years so it's good to get the replacements in place.

  • I have always wondered how much is reused. I have assumed that the engines are the most expensive part of the booster. Are they being reused? I have looked for that answer, but I have not found any info on this

    • by quenda ( 644621 )

      I have always wondered how much is reused.

      The whole first stage. This one was used for the Zuma launch in January, and landed back at the launch site.
      However it was not recovered today, which allows a greater payload.

    • SpaceX did not rebuild the booster after its first use. Basically 100% of the booster was reused.

      The reason the booster was not recovered was it was a Block 4 Falcon 9. They are only reusing them a maximum of one time. Basically they are trying to clear the old boosters from the inventory so they can move to the Block 5 boosters. They hope to reuse Block 5 up to 10 times before any major refurbishment.

    • by Terwin ( 412356 )

      When they re-use a block-4 booster they:
      1) remove the landing legs(need to be replaced if the second launch will carry them, Block 5 legs are reuseable)
      2) wipe off the soot over the welding seams and inspect those seams(the rest of the soot stays on for the second launch)
      3) Replace the grid-fins(if they were aluminum and will be used on the second launch, titanium ones are reusable)
      4) perform a new static fire test
      5) attach a new second stage with new payload and fairing(they currently are working on Second

Neutrinos have bad breadth.