The first U.S. attempt to land a spacecraft on the moon in more than 50 years is in jeopardy after the Peregrine lander vented fuel from its propulsion system while being used to address another issue. After a good launch aboard a Vulcan Centaur rocket developed by the joint Lockheed Martin and Boeing venture United Launch Alliance, the lander, built by Astrorobotic, was unable to orient itself for its solar panels to face the sun. When the propulsion system was used to fix that, the fuel started to leak.
Ground controllers were able to get the spacecraft in alignment to charge its battery, but the loss of fuel appears to be mission critical as far as actually landing on the moon is concerned. “The team is working to try and stabilize this loss, but given the situation, we have prioritized maximizing the science and data we can capture,” Astrorobotic said in a statement. “We are currently assessing what alternative mission profiles may be feasible at this time.” The first photo sent back from the lander shows damage to an insulating shroud on the spacecraft.
The landing fuel is the same source tank as the maneuvering thrusters?
I can see that the manufactures have forgotten basic fault tolerant systems.
Hadn’t seen too many spacecraft with fully redundant fuel systems. Multiple valves arrayed in series and parallel, redundant propellant lines, extra thrusters, yes, but don’t think I ever saw redundant tanks.
Propellant tanks are heavy, complex, and typically are spherical, which is an inefficient use of volume. Weight is incredibly critical in spacecraft design, and duplicate tanks would reduce mass available for other things and would rarely be necessary.
It sounds like we’re talking about descent fuel here… and it’s unlikely that it would carry, essentially, twice as much fuel as it would need (e.g., two redundant tanks). It takes a LOT of fuel to land on most objects.
Not at all familiar with the design of the Peregrine, but from Mr. Niles’ description, it sounds like they lost primary attitude control (possibly gyros) and used a backup system.
The Apollo lander did not share it’s descent fuel with maneuvering thrusters. Secondly, needing to charge batteries on a short trip to the moon is also a weird design limit.
There’s a difference of margins of safety between crewed and uncrewed missions. IIRC, it’s 1.1 for uncrewed, and 1.25 for crewed. Apollo probably needed more flexibility to respond to potential anomalies.
A second point is that you need BOTH attitude propellant descent propellant to land…well, if one of them develops a leak and drains out, a cross-feed doesn’t buy you much.
Let’s assume that Peregrine, as designed, needed 200 lbs of propellant to safely land (have no idea of the actuals). If you wanted to carry an ADDITIONAL 200 pounds, then that would be 200 pounds of science you’d have to leave behind.
Yes, not having full redundancy is a risk. Having that additional 200 pounds might have enabled a less-capable mission, but of course, that would beat digging a deep crater into the Moon.
It’s the kind of decision spacecraft designers have to make all the time. You try to analyze the risk, you try to mitigate the risk, but at some point you’re going to have to bite the bullet and decide. With careful analysis and thorough testing, one can gain a reasonable amount of confidence.
The damaged fairing on this is interesting…would like to know the story behind it. Maybe it’s just a light thermal cover that rippled normally, but otherwise it looks very much like some sort of explosive event. All bets are off, in that case.
When the trade-off is a new crater; they made a bad decision.
This kind of thing detracts from the great record that Elon, Virgin and other private space companies have been amassing. Putting all the fuel in one tank doesn’t seem like a first principles solution. I’m sure whoever was primary in signing off on the designs is wishing they’d dome something different.
Peregrine. Connected with the aircraft by that name?
What’s plan B for the delivery of the cremated human remains and DNA intended to be placed on the Moon?
Pretty sure lunar gravity will allow for the creation of a tall hole at the delivery point.
Correct. Ranger was a series of crashing lunar satellites that had no intention of soft landings on the moon in the early sixties, they sent back pictures of the surface right up to impact. Peregrine will probably be programmed to do the same.
This is a small illustration of how unlikely is a manned landing and return from Mars. Such a trip would take at least 18 months, and entail an exponentially more complex set of issues. This lunar landing attempt is child’s play by comparison, yet is failing. It doesn’t even have humans aboard, with all the life support required. A manned station on the moon is fraught with likely insurmountable difficulties. Cost being just one. Up till now, talk is cheap and funding goes to various studies and preliminary efforts. Real results are not yet demanded. But at some point, the true complexities and failures will become evident and the funding will dry up.
I agree.
The technological challenges of a manned Mars mission are many and they are complex (costly) in the extreme. Is it possible? Of course, but feasible and affordable? Not in my lifetime.
Either western civilization will recover from its diseased state and get its priorities straight, or the eastern people will catch up and do the job. It’s just a matter of time.
Only reason for the high risk of human moon landings was cold war politics; you’d die for your country. Mars is a 1000x more dangerous and there is no political advantage in it.
There is strategic and military advantage to Moon settlement and Mars settlement. If not the USA then another human culture and society will make that leap and soon.
This is such “click bait”, I couldn’t resist adding my two (probably useless in the higher order of things) bits. In the largest sense, humans are still 10,000 or more years behind their technology: unconscious non-verbal emotional feelings continue to strongly influence much human decision making in all endeavors. Hence the species repetition of idiotic decisions in organizational and political structures–war in all forms (including “business”) determining many proverbial shots to the feet. Will someone, sometime, make it to the moon and establish a “colony” there? Yeah. Will it be ideal? No. As long as the species continues on its trajectory, it will just be more of the same only carried out a quarter million miles away from the earth’ surface. And, no, I don’t have a solution beyond investing in programs that insure compassionate caring parents for every child…as if that’s going to happen.
Excusame, “10,000 or more years behind “ ! Your view paints a picture of the human race stuck in ancient habits, driven by emotions, and you’re not holding your breath for any remarkable change. According to you, even if we somehow pull off an AVweb colony on the moon, it’s likely to be just as messed up as what we’ve got going on Earth. It’s like, we’re stuck in a loop of making dumb decisions fueled by our emotions, and you’re not seeing any easy fix, except maybe a pipe dream of ensuring all kids have loving parents, which you think is about as probable as finding a unicorn.
But here’s another way to roll your eyes at it: Yeah, emotions can make us pull some seriously ridiculous stunts, but hey, people do manage to stumble upon new ideas now and then, though it often feels like a cosmic joke. Technology, for all its promise, sometimes feels like two steps forward, one and a half steps back. Admittedly, there are some truly mind-boggling reversals in the mix. Despite all the blunders, humans do occasionally stumble onto solutions to our messes. Setting up shop on the moon might be a wild ride, but who knows, maybe the challenges will inspire us to come up with some inventive solutions to our Earthly issues. And while trying to make sure all kids have caring parents sounds like a Herculean task, throwing money at education and support systems might just do something useful over time. So, while it’s far from a walk in the park, there’s a wee chance for positive changes and progress here. Go Packers!
Please remember that we use “rocket science” as an euphemism for something extremely difficult. We’re practically to the “ticket punch” mode for LEO, but it’s still difficult and still dangerous. Missions like this are difficult too. With 40 years in the space biz, I can sympathize with the Peregrine team right now.
Remember, too, we are talking SPACECRAFT, not airplanes. Little of the conventional wisdom we acquired as pilots applies. After the Columbia disaster, I remember the aviation forums filled with outraged postings about “Why didn’t they slow-fly it down.”
Ron, are you suggesting deploying mainetance crews orbiting to service Low Earth Orbit (LEO) craft from companies like SpaceX (Starlink), OneWeb, and Amazon (Project Kuiper) planning or placing constellations of small satellites?
No, I don’t see anything like that for quite a while.
As far as I know, there aren’t any current satellites…other than Hubble…designed for on-orbit servicing. You can’t just stroll up and hook up a propellant hose or whip out a wrench to open a panel. They’re just not designed for that. It would take a whole new series of satellites designed to allow this.
Along the same note, I don’t see it being done by humans. For a lot of modern spacecraft, it’d probably be cheaper to just launch a replacement instead of launching an astronaut, keeping them alive in space, matching orbits with the targets, and bringing them home safe again.
Possible…but, for the most part, they’d only be able to service ONE SATELLITE PER LAUNCH. Spacecraft don’t “fly”…they’re ballistic vehicles traveling in specific directions at 17,000 MPH. You might match courses with one, but you’d need a ton of fuel to rendezvous with a second satellite in a different orbit. Again, it’s like the Columbia disaster…a lot of pilots asked “why couldn’t it just fly up to the Space Station?” The answer is that it would have taken the same amount of fuel to match orbits with the ISS as it took to launch in the first place.
Starlink might be an exception to this. Every launch puts ~60 Starlink satellites in basically the same orbit. They spread out over time into an Earth-spanning ring, still in the same basic orbit. You COULD launch to the ring, visit one satellite, and travel to the next with a minor expenditure of fuel. But you couldn’t service another ring with the same launch, it would take too much propellant to match to its orbit.
But, of course, the satellites would have to be designed to support that, and you’d need the matching gear on your service vehicle.
Maybe SpaceX or some of the other companies might put some investment that way, but in the foreseeable future, it’s going to be cheaper just to replace them.
The company that built the lunar lander is called “Astrobotic.” The headline and article have a few spare letters.