Thursday Throughput for June 6, 2019


Michael Siegel

Michael Siegel is an astronomer living in Pennsylvania. He is on Twitter, blogs at his own site, and has written a novel.

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14 Responses

  1. Avatar Oscar Gordon says:

    3: that is quite a bit of movement, but a typhoon will do that.Report

  2. Avatar North says:

    ThTh3: I alternated between gaping in amazed delight and shuddering in terror at the idea of what that building must have been going through to produce that behavior in the mass damper. When they noted that the building was evacuated during the event I felt better. Modern architecture is so freaking cool. But Californian NIMBY’s say we can’t build anything over two stories in earthquake prone areas.

    ThTh8: If there is a hell; the parents of these little plague kids should be rotting in it. This is an utter fiasco and a national embarrassment.

    ThTh1: I am so divided on this. I mean the satellite network seems so extremely useful. I get the concerns though. Is this one of those science vs the masses things? Do the satellites being up there really screw up the science that much or is it more of an annoyance thing?Report

    • Avatar Oscar Gordon says:

      Regarding satellites, it’s one of those things where it’s be awful nice if perhaps, before we toss up a huge constellation of satellites, we could bring down a bunch of the useless ones that haven’t de-orbited on their own yet.Report

      • I like that idea. Similar to the effort to clean up Everest.Report

      • Avatar North says:

        How hard is it though to do such a thing? I understand the velocities involved make it essentially like trying to catch flying bullets. Obviously there’s a reason all that junk in low earth orbit hasn’t decayed out of the sky already. I’m assuming, based on my miserable neophyte knowledge of space, that sending a device up to intercept one piece or one cloud of pieces of junk would be expensive but possible but that sending a device up to intercept many different clouds of junk on many different orbits is flat out impossible?Report

        • It’s hard. Because you can’t just use a big net. When thing collide, that just creates more debris. There has been talk of using a laser broom to ablate objects and push them down into the atmosphere.

          Right now, the biggest concern is Envisat, a massive ESA satellite in a dangerous orbit that will be up there for 150 years. If I were appointed NASA head, one of my priorities would be mandating that every mission be equipped for deorbit and plans be drawn up to deorbit existing satellites.Report

          • Avatar Michael Cain says:

            If I were appointed NASA head, one of my priorities would be mandating that every mission be equipped for deorbit…

            In the US, satellites are regulated by the FCC, not by NASA. The FCC has end-of-life requirements, either deorbit or graveyard orbits for geosynchronous satellites. Opinions differ on whether the Outer Space Treaty should be read to require a deorbit plan.

            For private satellites, the OST places full liability for damage on the country in which the satellite owner operates. Recently there were stories in the news about a US company that couldn’t get an FCC license, but arranged to have their sub-cubesat devices launched by India. They were in serious trouble with the FCC because the US will be responsible for any damage they do. They may have been fined into oblivion — don’t know.

            Cubesats generally are a problem. They mostly don’t have maneuvering thrusters, and as they are often launched as supercargo, may wind up in orbits other than those in their license.

            Most countries have deorbit requirements. India and China are a problem because they don’t.Report

        • Avatar George Turner says:

          I’ve suggested a simple suborbital rocket that goes straight up, reaching apogee in front of the targeted satellite, and fires a pair of opposed horizontal rocket engines along the flight path. The rocket exhaust is two long plumes of rarefied atmosphere that create drag, yet not enough drag to dislodge anything on the satellite. It might take two or three such hops to bring one down, but suborbital launches of a re-usable vehicle shouldn’t be very expensive.Report

        • Avatar Oscar Gordon says:

          There have been a number of links on past Tech Tuesdays talking about technologies to de-orbit satellites. It’s a non trivial issue. It’s easier to have a satellite equipped with a means to de-orbit itself.

          There are a lot of smart ideas out there, but resurrecting some old Reagan Era Star Wars ideas and putting a “Laser Cannon” in a high orbit, so it can zap older satellites out of orbit just sounds nifty. Targeting the laser is still a feat, but it’s one we can do well enough. I can just imagine that the award at JPL for an employee of the month is getting to be the junk gunner for a while.Report

    • Avatar George Turner says:

      StuffIn.Space, which lets you see all 20,000 satellites in real time. You can click on one to see its orbit and various parameters.Report

  3. Avatar dragonfrog says:

    ThTh1 – Elon Musk is an idiot. He’s very smart, so his idiocy is the particular arrogant clever kind of idiocy that very smart rich people sometimes fall into, but he’s still an idiot.

    ThTh7 – My understanding is that the IPCC report is unrealistically optimistic. It leaves out a couple of important feedback loops, notably the release of methane from melting permafrost.Report

    • I addressed that a few Th2’s ago. The methane bomb seems to be an exaggerated danger. The IPCC report has a number of scenarios, some of which are very pessimistic.Report

    • Avatar Michael Cain says:

      ThTh7 — I got e-mail from the Inslee campaign this morning. (Full disclosure: I sent Inslee money because I want the climate change issue to be as front and center as possible.) They had sent a letter to the Democratic National Committee asking that one of the debates be broadly climate focused: not just about renewable electricity, but how it should affect foreign policy, etc. The DNC response reportedly said that there would be no such debate. Further, it supposedly said that any candidates who took part in a non-DNC climate debate would be barred from all future DNC debates.

      My son’s girlfriend works on climate models for NOAA/NCAR. She says that most of the known unknowns — things we know aren’t done well in the models — are things that make the outcomes worse.Report

  4. Avatar greginak says:

    I agree on Musk. Space X is great but damn if he is almost a cartoonishly sure he knows everything and everybody should love him rich narcissist. He is not going to cope well when he has serious setbacks and something big fails. That happens to everybody especially when they go big like he does. He is careless and clueless about things that get in his way.Report