India’s Polar Satellite Launch Vehicle, a remarkably reliable rocket, has just completed its most technically challenging launch to date, placing ScatSat 1 (an Indian weather satellite), Pathfinder 1 (a prototype commercial imaging satellite from American company BlackSky), AlSat 1B and AlSat 2B (a pair of Algerian Earth imaging satellites), an Algerian CubeSat, a Canadian CubeSat called CanX-7, and a pair of Indian student-built satellites called PRATHAM and PISAT. The complex deployment pattern required the PSLV’s fourth stage to relight twice, a first for the vehicle and a major step in positioning it to continue competing in the international launch market. This capability is critical for multi-payload deployments, an increasingly popular method of getting one’s payload into orbit more cheaply, especially as small satellites become far more capable.
Scientists studying the data from New Horizons have had an absolute wonderland to play in, but one of the most compelling features right from the start was definitely Pluto’s “heart” — a vast white plain called Sputnik Planum that covers a huge portion of the surface. It’s completely unlike the rest of Pluto’s visible surface, is clearly very young, geologically speaking, and has a curious geometrical coincidence: it’s directly in line with the the Pluto-Charon barycenter. Pluto and Charon are mutually synchronous — that is, due to tidal interactions between the two bodies, they have settled into an arrangement where one rotation of Pluto is the same as one rotation of Charon and also one revolution of Charon. Our own Moon rotates synchronously — it is tidally locked to the Earth, which is why we only ever see one side of it. But the Pluto-Charon system has evolved further: not only is Charon locked to Pluto, but Pluto is locked to Charon. If you stood on Sputnik Planum, you would see Charon fixed immobile in the sky above you, going through its phases as you experience day and night, the stars and Sun and planets wheeling through the sky behind it. It would be a very strange sight to us.
It’s also very suggestive of a positive mass anomaly (a region which is much denser). Charon is quite large relative to Pluto, and orbits fairly close; this means that tidal interactions will inevitably drive the system towards a condition where the densest part of Pluto points towards Charon, and that is exactly what appears to have happened. Planetary scientists believe that Sputnik Planum was created when a very massive asteroid impacted Pluto – not big enough to produce Charon or anything like that, but big enough to liquify a lot of the planet, leaving a huge scar similar to the massive impact basins on the lunar nearside that we call the maria. If there is still an enormous liquid water reservoir below Sputnik Planum, it would explain a lot of the surface features as well as the positive mass anomaly that is believed to exist in that location, because as anybody drinking a glass of ice water can easily see, liquid water is considerably denser than solid water. This weird feature of water could entirely explain Sputnik Planum and its location on Pluto. Doing the math, researchers estimate the ocean below Sputnik Planum could be 100 km deep, and about 30% salinity (comparable to the Dead Sea on Earth, and so not beyond the limits of what we know life can handle).
It also means that Pluto doesn’t just have a heart — Pluto has a broken heart. But out of that broken heart comes beauty that no one had ever dreamed of:
SpaceX is far from completing their investigation, but they already have an intriguing piece of information to share with the public. Although this is not the root cause, they have determined that the helium tank in the upper stage’s liquid oxygen tank ruptured violently, leading to the loss of vehicle. They don’t yet know why the tank ruptured, however, so the investigation has a lot of work still to do. This does give them some confidence that it is not related to the last Falcon 9 mishap, which also involved a helium tank. That one was found to be due to the failure of a strut supporting the helium tank within the upper stage LOX tank; this failure appear to have been in the tank structure itself. It’s a carbon composite structure with considerable engineering heritage, but there are still many unknowns and SpaceX has to keep working. All the same, it’s encouraging they continue to share some information with the public during these investigations, and I hope they are able to return to flight in a speedy manner without compromising safety.
The current SpaceX launch backlog for 2016 alone includes:
- A set of 10 small satellites for the Iridium-Next network, currently sitting in a hangar at Vandenberg AFB.
- SES-10, originally set to fly from CCAS, might become the LC-39A trailblazing flight
- Formosat 5 & Sherpa, for Taiwan and a commercial outfit that plans to launch Cubesats from their Sherpa mothership
- Echostar 23
- Dragon CRS 10
- SES 11/Echostar 105
- Koreasat 5A
- Iridium Next 11-20
The Falcon Heavy test flight has already been pushed to 2017 for other reasons, joining an already-busy manifest for 2017. SpaceX’s has been keeping up a punishing launch pace that exceeds any other platform, so this delay is a serious issue for them. Hopefully having progressed as far as they have already means they will have a solution quickly. However, this will likely put a damper on efforts to persuade NASA to accept the Full Thrust Falcon 9 for the crewed Dragon, which will have to be fueled minutes before launch, with the crew already on board.
Here’s something short, sweet, and ridiculous that I wrote back in college. It’s basically the intro segment for a Doctor Who/Red Green crossover. If someday I ever decide to write the rest of it, the Doctor will undoubtedly never appear, much like Moose Thompson or Red’s wife Bernice.
DUCT TAPE TARDIS
a Red Green/Doctor Who crossover vignette
by Calli Arcale
Note: If you’ve never seen The Red Green Show, don’t both reading this. Instead, go and watch The Red Green Show! If you repair things with duct tape, or know someone who does, you’ll love it! Plenty of good ol’ northwoods humor from these fellahs up in Canada. (Also, most of it’s all on YouTube these days!)
Harold: “It’s the New Red Green Show! With your host and my uncle, Red Green!”
<Studio audience cheers as Red Green swaggers in, looking extremely pleased with himself.>
Red: Well, I’ve done it. I never thought it could be done, but I did it.
Harold: <sniggers> What, didja get the Possum Van to do more than two blocks to the gallon?
Red: No, this is better ‘n that, Harold. In fact, I think it’s the best thing ever. We’ve found a new use for duct tape.
Harold: Other than keeping your hat on?
Red: No, Harold, we found it makes a pretty good substitute for Zeiton-7 ore.
Red: Works wonders for stranded time machines.
Red: We’re thinkin’ aboot maybe settin’ up some kind of deal with Magellenic Mining Corp. They want to move into Port Asbestos.
Harold: Y’know, Uncle Red….
Red: <completely ignoring Harold> And the best part is, it even comes with its own built-in adhesive, eh? So you don’t have to bolt it to your time drive. Ya just put it in sticky-side oot!
Harold: Look, Uncle Red, you do know that time travel is a mathematical absurdity.
Red: Who knows that?
Harold: Everybody knows that.
Red: No, they don’t.
Harold: Yes they do.
Red: No, they don’t.
Harold: Yes they do. Einstein said….
Red: Oh, forget aboot Einstein! There’s this guy ootside with a big blue box that says “police” on it. He says its true, and I for one believe him.
Harold: Why would you believe a complete stranger?
Red: Because anybody who travels in a stolen vehicle with the word “police” on it is definitely a Lodge member. Especially with his fashion sense.
Harold: I’d say that’s a good reason *not* to trust him.
Red: Well, that’s what they all told Bernice. Luckily for me, she didn’t believe them!
<cue Red Green intro>
A sad update on the Vandenberg wildfire: although crews as of this morning had the fire 70% contained, it has now claimed its first victim. Well, not directly. A firefighter responding to the fire was killed when his water truck overturned on the way in to fight the fire. The Santa Ana winds fanning the fire also make it more difficult for top-heavy firefighting equipment to navigate the dangerous roads in the area. Keep his family in your thoughts; the firefighters who tackle wildfires are a special breed, who take extra risks the rest of us would never contemplate.
Crews are making significant progress fighting the fire, however, and off-base evacuation orders have now been lifted. The base is expected to soon return to normal operations. What everybody really needs down there, though, is some rain. The longstanding Southern California drought has greatly elevated the fire risks.
Soyuz MS-02 has been undergoing preflight processing at Baikonur Cosmodrome, and the three crewmen (Sergey Ryzhikov, Andrey Borisenko, and Shane Kimbrough) had flown to Baikonur to begin preflight activities pending launch on Friday. However, the launch has now officially been delayed indefinitely, and the three have flown back to Star City, outside Moscow. The spacecraft, s/n 732, was encapsulated in its payload fairing and returned to its vertical position for additional fit checks prior to integration with the Soyuz-FG rocket. However, during those tests a short circuit was detected. The short apparently was caused during encapsulation, since the spacecraft had passed testing prior, but unfortunately it will not be possible to locate the short without removing the fairing. This alone sets the schedule back. Roscosmos has estimated that if the short turns out to be in the orbital module, it will take weeks to fix, but if it’s in the service module, it could take months. In that case, they’d likely go to plan B and start processing spacecraft s/n 733 for the Soyuz MS-02 mission, and buy a little more time to get 732 fixed and ready to fly as Soyuz MS-03.
The ISS currently is on a skeleton crew, as the current crew of three awaits the next inbound Soyuz crew. There is no timetable yet for when that will change. It does underscore the need for a second crew transfer method, but neither CST-100 or Dragon is likely to be ready before 2018.
(reference: Anatoly Zak’s RussianSpaceWeb blog)