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67

Right now, almost 100% of existing research on growth in gravity fields is basically at 0g (ISS/Mir/Skylab/whatever) or 1g. There are a lot of questions of what happens at 1/6g or 2/3g? No good experiments to demonstrate. Thus the Chinese lander is testing 1/6th g. SpaceX is likely to brute force test 38% g when they get to Mars. It is entirely possible ...


41

While it's still cool, it's not as tricky as it may sound at first: The seeds, including water, are stored in a sealed, heated and shielded container. The container also includes fruit flies and yeast. So the plants are not grown in the lunar soil (which would be the interesting and challenging next step) but in a portable, sealed ecosystem. (See for ...


32

The mission objectives are: The main scientific objective of CE-4 is to provide scientific data for lunar far side research, including: 1) general spatial environmental study of lunar far side;2) general research on the surface, shallow layer and deep layer of lunar far side;3) detection of low frequency radio on lunar far side using Low Frequency ...


27

tl;dr: There are "96 bags of poop, pee, and puke" on the Moon already! The bags of waste are ecosystems for sure, but like the ones you mentioned, they are not going to remain alive for very long. From Gizmodo's There's Poop on the Moon: There is, however, scientific value to the things left behind. Astrobiologists, for instance, hope to one day ...


18

That's unburned $\mathrm{N}_2\mathrm{O}_4$. The zeroth and first stages of the Long March use $\mathrm{N}_2\mathrm{O}_4$ and $\mathrm{UDMH}$. The Dnepr uses the same propellants. I doubt that the red gas you see is from the cold launch system. That system uses a black powder mortar.


13

Why did China land a rover on the moon? (Chang'e-3) Hover cursor above to reveal answer. (Hint: analogous to Why did the chicken cross the road?) But seriously folks, here is a one hour English CGTN broadcast of the mission, going into great detail on the justification and goals.


12

The given value (2kg) is approximate and won't be known exactly until the container is recovered. Knowing the typical composition (including density) of Moon rocks and the volume of the container, one can easily foresee the average mass of the samples, but the actual mass will depend on the local composition, granularity (amount of empty space between grains)...


10

According to Jainism and some forms of Buddhism, the concept of Ahisma tell us that it not ethical to bring an ecosystem of living creatures to an environment that will almost assuredly kill them as a result of you bringing them there. Ahinsā (Ahinsā) in Jainism is a fundamental principle forming the cornerstone of its ethics and doctrine. The term ...


10

Humans have already been to the Moon, and pretty much verified it is completely sterile. It isn't really an issue bringing plants to the Moon, it couldn't contaminate anything, as there is nothing there it could really affect. Besides, anything complex couldn't survive in a vacuum, and there's been plenty of bacteria that have been on the Moon from the ...


10

It did perform the observations, but nothing was detected. Here is an article that covers this Surprisingly, the LADEE science teams' preliminary evaluation of the data has not revealed any effects that can be attributed to Chang'e 3. No increase in dust was observed by LDEX, no change was seen by UVS, no propulsion products were measured by NMS. ...


10

Surveyor Program landers (1-7) made robotic soft-landing on the lunar surface. The major difference between Surveyor landers and Chang'e 3 is that they didn't orbit the Moon, but were put on a ballistic trajectory and the autopilot computer did the rest. NASA page on Surveyor 1 puts the soft-landing procedure like this: For the landing sequence, an ...


9

Emily Lakdawalla was covering this naming process for the Yutu (玉兔) rover in her Planetary Society blog posts for the majority of us Westerners that don't speak Chinese (yours truly included). In one of her posts, she describes it like this: Yesterday the Chinese space agency held a press briefing about the Chang'e 3 lunar lander. They announced that ...


9

The view is horizontal as the spacecraft seems to stop and hover over the chosen site, and then the view pitches forward until it is looking straight down. According to the graph linked by @AlexanderVandenberghe, that pitchover is happening at 6-8km altitude, so I think what you're interpreting as a "stop and hover" is not a hover. It's falling, but the ...


9

They did it for propaganda or pride mostly. What sprouted quickly died because it froze. They did not have a method to protect the biosphere from the temperature swings. This is what they expected and admit. The Chang'e-4 probe entered a "sleep mode" on Sunday as the first lunar night after the probe's landing fell. The temperature could drop as ...


7

According to the Planetary Society, they ran a competition$^1$ for an experiment to make use of spare capacity on the lander. This one was chosen, most likely for it's potential to cultivate interest in the mission. $1$: On January 8, 2016, the Chinese Lunar Exploration Program (CLEP) released an unusual "Call for Proposal" to the general public, ...


7

The announcement was first made by the vice principle of Chongqing University (the primary designer of the growth module) on the 15th of January and you can find the original article summary from their university website here (in Chinese of course). The first image is from the lunar module (the actual time the photo was taken was 7th January around 10am). ...


7

I don't think there are any more beyond those you listed. There would be three reasons to perform a docking: Demonstrate capability Bringing something back Assembling a larger structure As no assembly as taken place beyond Earth orbit so far, 3) is ruled out. 2) I relatively simple to cover, since the only things worth the high cost of recovery is humans ...


6

According to Spaceflight Now (emphasis mine): Chang’e 4 is expected to enter lunar orbit Tuesday [Dec 11 2018] after a series of course-correction maneuvers, then use braking rockets to descend to the moon’s surface, targeting a landing inside the 110-mile-wide (180-kilometer) Von Karman crater in moon’s South Pole-Aitken basin region in early January. ...


5

Here's the link: http://moon.bao.ac.cn/searchOrder_dataSearch.search You may need to create an account. Scientific Data -> Search -> find your data and download. The website is extremely slow, and not user friendly at all. The search page is so slow, may take 30-180 seconds to load. The download link looks like: http://moon.bao.ac.cn/cedownload/CCD/...


5

Several factors contribute to needing a large antenna: it is used to communicate with the rover, which weighs only 100 kg so can't carry a large dish it'll be in orbit at the Earth-Moon L2 Lagrangian Point, a distance of 60,000 km from the Moon. the lander and rover use omnidirectional antennas (i.e. with low gain) to receive data These factors are all ...


5

Due to several requests (1, 2), I will answer my own question. I have found the following... Leonard David's INSIDE OUTER SPACE blogpost Farside Science: The Saga of Ranger 4’s Moon Journey There’s an interesting historical side note given China’s imminent, milestone making robotic landing on the farside of the Moon. The U.S. Ranger spacecraft series was a ...


5

I don't know the exact path, but I do know there's a path to the moon that takes about a month. The reason it's used is that it takes less energy. The Apollo missions got there in three days but your economics are different when you are consuming supplies for every day in space. See this question for more information: Low Energy Transfer within Earth-Moon ...


5

Just checked from the JPL Horizons website. It seems that it is in fact still there. I also looked at the JPL Small-Body Database. Looking up Toutatis, it says it was last updated in 2003. It seems very unlikely that it was specifically deleted because China wanted to send a spacecraft there.


5

This answers the question as originally asked: How many docking operations have taken place beyond Earth orbit? Zero. All of the examples listed took place in Earth orbit. The moon orbits the Earth, so anything done in its vicinity is still occuring within Earths gravity well. per Wikipedia, Beyond Earth Orbit (BEO) require[s] an insertion into a ...


4

I grabbed a couple pix from SkyAndTelescope which may help. On a macro scale, you can see that the path is chosen to avoid craters and whatnot: This next one is a better version of what you posted, and again it looks like the tracks are avoiding various craters or small dips in the landscape:


4

Question: What are the stated or otherwise likely future uses for this space station beyond servicing China's upcoming Chang'e 4 mission and Queqiao satellite on it's way to the Moon? The article "China Builds Space-Monitoring Base in the Americas" (The Diplomat, May 24, 2016) explains many things and has really great photos of China's military base in ...


4

The Earth-Moon L2 is located about 1.16 times as far from the Earth as the centre of the Moon (wikipedia, so the Earth is about 7 times as from L2 as the Moon is. Since the Earth is less than 7 times the Moon's diameter the Moon would protect a telescope at L2 (or in any small halo orbit around it) from all radio noise directly from the Earth and from LEO. ...


4

There is a Chinese run ground station in Swakopmund, Namibia. Image source This station is part of the "Chinese Tracking, Telemetry, Command and Communications System", which has similar stations also in Karachi, Pakistan and Malindi, Kenya. See https://en.wikipedia.org/wiki/Swakopmund_tracking_station for more information.


4

In 2014 China and Argentina signed an agreement that allowed China to establish and operate a deep space station in Argentina. According to Reuters, the Chinese military runs the station in Argentina. The site is on a 200 ha compound, in a remote part of Argentina. While it still has access to an Australian space dish, at Yatharagga in Western Australia, ...


3

Looking through this image archive, they haven't taken photos where stars are the main subject. All photos in that archive were done in daylight. I've removed the processed photo - I found 2 bright pixels in the shadowed region of the Earth, so those can't possibly be stars. Chang'e 3 hibernates during the lunar night. It's not clear if the probe ...


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