Chinese rocket junk may have just smashed into Moon A chunk of Chinese space junk today crashed into the far side of the Moon, according to a maker of astrometry software. The trash is believed to be a spent Long March 3C rocket booster from the launch of Chang'e 5-T1, a Chinese experimental robotic spacecraft that lifted off in 2014. The leftover component was estimated to …
Gray argued that scientists should start paying attention to junk further out into space: "Many more spacecraft are now going into high orbits, and some of them will be taking crews to the Moon," he said. "Such junk will no longer be merely an annoyance to a small group of astronomers."
Someone at the US Space Force has been paying attention. They plan to extend their monitoring from geostationary to the Moon.
The earth-moon tidal effect is pushing the moon further away from earth so it’s not coming down, probably this and other accretions make it go away faster. The result is to make earth days longer as we spin slower.
But on the scale of human lifespans, or even human existence a tiny tiny negligible amount.
An interesting thought problem, of the sort that would be useful for a physics instructor. Somebody should ask Randall Munroe to do a "What if" about this.
The net effect on the earth-moon distance would be (drum roll...) effectively zero. If you look at most of the formulae for orbital speeds and periods, they rely on M+m (sum of the mass of the primary and secondary). Often, m is considered negligible (for spacecraft or small asteroids, for example), but it wouldn't be in this case.
So even if you somehow got significant amounts of mass from the earth to the moon, M would drop a bit and m would go by the same amount, it'd cancel out, M+m would remain unchanged, and we'd remain about 385000 km apart and orbiting each other about once a month.
I'm ignoring here the side effects of getting that mass to the moon. If rockets are involved, some of the exhaust may leave the earth-moon system, and M+m will _drop_ and the earth and moon will recede from each other. Also, there's a slight gain or loss of energy and angular momentum if the object impacts, rather than soft-lands, on the moon. If we found that the accumulated impacts had resulted in a lower orbit for the moon, we might have to switch to having them impact the other side for a while to balance things out.
Neat, but are you taking into account the difference in mass between the two? Assume the mass is a one cubic foot block of solid iron. If that block were sent from Earh to the Moon, the percentage of mass lost from Earth's mass will be much smaller than the perdentage of mass increased on the Moon. Assuming no orbital speed change, the mass swap should cause the Moon to spiral in as the loss of Earth's gravity would be less than the increase of the Moon's gravity.
Mind you, I'm not saying the difference would be huge, or maybe even measurable, but this is how it should work. The larger the difference in mass, the larger the change should be while as the mass transfer comes closer to giving both equal mass, the less the difference should be. Once the Earth and Moon reach equal mass though, either they crash into each other or they begin to orbit a common point between them, but by then we're all frozen yet crispy corpsed and the discussion comes to an end.
"Once the Earth and Moon reach equal mass though, either they crash into each other or they begin to orbit a common point between them"
The Earth and Moon already orbit a common point, called the barycentre. That point is located about 2900 miles from the center of the Earth.
"At least China isn’t following the USA’s example. Rangers 7, 8, & 9, and the S-IVb stages of Apollo 13/14/15/16/17 were all deliberately crashed into the moon."
There wasn't the tech and computing power to do something less dramatic with the Rangers. Perhaps there should be a designated area of the moon that used rocket stages should be directed to. After a while, it would be an enormous pile or refined metal that could be used to manufacture stuff on the moon without have to go through a smelting process to make metal from ore.
Impressive achievement if you're aiming for it; it's quite big, really. Nearly 456 Wales, 4 DRCs during full moon, but maybe they fired those Rangers at it while it was half-moon or even less.
They could also have put a cracker cladding on the front as that would certainly be attracted by the moon's cheese, but apparently NASA chose to approach the targeting problem with technology instead of with common sense.
Interestingly, Kurzgesagt did a video on this kind of event recently, linked below:
https://www.youtube.com/watch?v=lheapd7bgLA&ab_channel=Kurzgesagt%E2%80%93InaNutshell
The rough take-aways are:
- Nothing short of magic or a rogue planet / star is going to disrupt the Earth / Moon orbit system.
- Even if the Moon did suddenly stop in it's orbit and head towards the Earth, it would never reach it. Tidal / gravitational forces would tear it up and turn it into a nice new ring system for the Earth
- Even though the Earth wouldn't suffer a direct impact, civilisation would have one hell of a time thanks to nightmare tides, tectonic disruption and meteor bombardment. Humanity would likely survive, but civilisation probably wouldn't.
I recommend watching the video, it's good fun.
When something bad happens, it's obviously the evil Soviets Chinese. We never do evil. Like Google.
(Not saying that this wasn't Chinese, I don't know anything more than what I'm told to believe, but that it is conveniently supposed to be Chinese does trigger my overly sensitive BS detector: It's the "crying wolf" syndrome.)
Not content with just polluting the earth, the Chinese are now polluting the moon. Just great.
I'm absolutely certain your great grandchildren will thank vilify you for holding that opinion.
I think all our grandchildren aren't going to be particularly pleased with the state we've left this place in. My parents generation knew about this and they've done fuck all, our generation is doing fuck all, and I expect the next, once they're old enough to have the nice shiny things that we'll all have to cut down on will do as little as possible either. (That's humans for you).
As to the moon, if we can extract useful resources from of the moon in a way that means we have to extract less of the useful resources from the world we live on, then I'm all for it.
We're not really looking after this planet very well, and if we all want the same standard of living then something needs to be done differently; and telling a load of people that they're not entitled to or shouldn't strive for parity isn't the solution.
There were some seismographs on the moon to measure Moonquakes (https://en.wikipedia.org/wiki/Quake_(natural_phenomenon) ). Sadly they are no longer operational*, unless someone has installed some more recently? As the mass fo the Moon is approximately 1,000,000,000,000,000,000,000,000 Kg**, the impact of small rocket booster is unlikely to have any measurable effect on its orbit around the Earth.
*"Several seismic experiments were deployed on the Moon by the astronauts during the Apollo missions. The experiments began in 1969 with Apollo 11, and continued with Apollo 12, 14, 15, 16 and 17. Instruments at Apollo 12, 14, 15, 16 and 17 remained operational until the final transmission in 1977." https://ui.adsabs.harvard.edu/abs/2020SSRv..216...89N/abstract
**https://nssdc.gsfc.nasa.gov/planetary/factsheet/moonfact.html
We've had regular reports about this in our media for weeks now.
Its not the first piece of junk to collide with the Moon. Early lunar vehicles like the ascent stages of Lunar landers were discarded to crash there after use. I personally don't like the notion of just tossing junk away to go 'wherever' but the focus on this says more about the current state of propaganda than anything particularly newsworthy.
What we need to focus on is not the story but the meta-story. Why is this important? Why does it merit conspicuous story after conspicuous story? What are people trying to tell us? (...apart from it being free copy, saves having to write stuff from scratch, always useful)
I really like that the BBC felt it was needed to write that "The effects of the impact on the Moon should have been minor."
Using "should", right, just to keep a lingering threat, because after all, it's /Chinese/, who knows what it could do, spin the Moon right out of its orbit, or something.
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