0
$\begingroup$

For the Apollo missions, it has often been said that images of other stars/milky way galaxy could not be captured since they mostly landed in sunlit areas and the reflectance of moon's surface prevented the camera's to adjust for the outer space.

Have any probes to the moon captured such images? Are they available publicly?

Recently, India sent a lander+rover to the moon and they were set to sleep mode due to oncoming lunar night. Was it not the perfect opportunity to capture the starry sky?

$\endgroup$
10
  • 4
    $\begingroup$ I'm sure you could do this, but as we have multiple space telescopes already what value would this have? $\endgroup$
    – GdD
    Sep 5 at 15:13
  • 2
    $\begingroup$ Compared with the cosmic distances between objects involved in the Milky Way galaxy, the distance from the earth to the moon is insignificant and, therefore, there would be infinitesimal differences in a display of the Millky Way from the moon vs one from the earth. $\endgroup$
    – tckosvic
    Sep 5 at 15:48
  • 2
    $\begingroup$ The real problem here is that during lunar night, a lander won't have power (unless it's designed to run off an RTG or some other non-solar power supply) and as a result we don't generally get pictures of anything. And usually lunar night is the end of the mission -- two weeks of dark is pretty rough to come back from. Battery packs freeze up and go nonfunctional in that kind of situation. $\endgroup$ Sep 5 at 17:04
  • 1
    $\begingroup$ @DarthPseudonym since there's no atmosphere, you don't need to be on the dark side of the Moon; you only need to shield sunlight from entering your eyes or a camera or telescope's lens. Had an astronaut had enough time to stand in the shadow of a lunar lander for 15 minutes and then look up at the sky through a rolled-up tube of black flocking paper to block light distant sunlit landscape, they'd have had a view of the sky darker than any ever seen on Earth. $\endgroup$
    – uhoh
    Sep 5 at 21:17
  • 1
    $\begingroup$ @GdD publicly funded spacecraft take all kinds of pictures that don't necessarily have any scientific "value" and yet have plenty of value in terms of public outreach. $\endgroup$
    – uhoh
    Sep 5 at 21:22

3 Answers 3

5
$\begingroup$

I haven't done a thorough survey yet but the first telescope on the Moon was set up by the crew of Apollo 16.

It was an ultraviolet system - observing wavelengths that can't pass through Earth's atmosphere. I believe it was a similar if not same design that was flown later on Skylab:

I can't support the following right now, but it's my understanding that the first orbital space telescope worked in ultraviolet, and most of the early suborbital space telescopes launched from sounding rockets were also ultravilet imagers.

The Chang'e 3 Lunar Lander also had an ultraviolet telescope to look at other galaxies and I think it's likely they took some photos of regions in our own Milky was as well. It also had an extreme ultraviolet (EUV) camera but it's primary purpose was to look at "Earth's plasmasphere".

And of course addressing @GdD's concern

I'm sure you could do this, but as we have multiple space telescopes already what value would this have?

...back in 1972 there was no Hubble space telescope.


Images of milky way galaxy from Moon?

One of the main targets of the Apollo 16 space telescope was the large Magellanic cloud which while not exactly part of the Milky way galaxy per se it's a close enough cousin (gravitationally, spatially) that it's worth mentioning.

"File:S-72-39660 Megellanic Cloud far-UV.jpg" https://commons.wikimedia.org/wiki/File:S-72-39660_Megellanic_Cloud_far-UV.jpg

Immediate source: File:S-72-39660 Megellanic Cloud far-UV.jpg

This photo is Figure 4-23 of the Apollo 16 Preliminary Science Report (NASA SP-315), which has the following caption: Color-enhanced far-UV photograph of the (Large) Magellanic Cloud. Ultraviolet radiation from specific astronomical targets was recorded on special spectroscopic black-and-white film in the far-UV camera/spectrograph. This photograph of the Magellanic Cloud, the nearest neighboring galaxy to the Milky Way, has been color enhanced to facilitate interpretation. Areas of similar intensity, recorded as a narrow range of gray tones on the black-and-white image of the UV-sensitive film, are reproduced as a color. In this photograph, blue areas indicate UV radiation levels below the threshold of detectability. Several other levels of UV intensity are indicated by different colors, such as red (faint UV), yellow (stronger UV radiation), and orange (most intense UV radiation within this field of view).

Original source: Apollo 16 Preliminary Science Report (NASA SP-315), 1972


From How was the Moon's first telescope used? (Apollo 16)

enter image description here

Source

$\endgroup$
3
  • 2
    $\begingroup$ Whereas this answers my question about 90%; what I was looking for was a night sky view from moon in the visible spectrum (true color!). $\endgroup$
    – anurag
    Sep 6 at 7:24
  • $\begingroup$ @anurag I think there can be more answers posted, give it some time. This is what I can offer but I'm sure there will be other answers as well. $\endgroup$
    – uhoh
    Sep 6 at 13:27
  • 1
    $\begingroup$ @anurag once your question has been here 48 hours, I can add a bounty to it - a sort of reward for any information about "a night sky view from moon in the visible spectrum". $\endgroup$
    – uhoh
    Sep 6 at 21:53
4
+100
$\begingroup$

There certainly are photos of the starry sky from the moon. The best I can find are the shots taken by Apollo 16's ultraviolet camera, which was shielded from the sun and pointed up to keep the ground out of frame. Most of it looks like some variation on this:

A bunch of stars seen through a circular aperture

Of course it couldn't take any pictures that included the moon's surface, which would have washed out anything else in the shot.

The only moon landers I know that survived at night (where you'd have a decent chance of getting a photo of the milky way) were the USSR's Lunokhod 1 & 2 and China's Chang'e 4, but as far as I can tell they never actually operated in the dark. Power was supplied by solar panels, and while they each had a lump of radioactive material aboard, it was only used to keep the probe warm at night rather than being a true radio-thermal generator (that is, there's no power output).

Some of the photos taken by the Lunokhods show white specks in the black sky, but I believe those are artifacts introduced by the camera and transmission (possibly cosmic rays impacting the panoramic camera?) rather than actual stars as is sometimes reported, as I can find no images that suggest the terrain is not sunlit.

Lunokhod 1 panoramas

It's not much, but one photo I found of Chang'e 4 (taken by the Yutu-2 rover) does seem to contain stars -- just a couple, barely visible on either side of the antenna mast. They're extremely washed out but there is something there. (Click to get a larger view where they're easier to pick out.) It's possible those are artifacts, reflections, or dust on the lens, though.

The Chang'e 4 lander with maybe a few stars just barely visible

$\endgroup$
13
  • 1
    $\begingroup$ @uhoh On further investigation I'm going to withdraw that claim entirely -- information about the Lunokhod rovers seems to be questionable at best. While I found some websites identifying "stars" in the pictures, they're shown in shots with brightly lit landscape that suggests to me those are artifacts rather than actual stars. Furthermore they didn't have RTGs; rather the rovers had to shut down at night and used radioactives only for heat rather than power, which was 100% solar. $\endgroup$ Sep 8 at 0:35
  • 1
    $\begingroup$ The Chang'e 4 photo is complicated. I think most of what you can see zoomed-in in the 1208 x 783 photo are artifacts. This becomes more obvious if you look at a copy of the original 5390 x 3111 photo and zoom in on them. Also they are all clustered just above the lander, and all have a greenish tint to them, so they could be reflections. And no other stars in the sky - except I did find three possible stars, but you have to zoom in nearly all the way in the original photo to see them. Unlike the $\endgroup$ Sep 10 at 5:01
  • 1
    $\begingroup$ others, these are very sharp even at high zoom. I circled the location of the three candidate stars in this lower res version. You can't see them in this photo but you can use it as a guide to find them in the original photo. Oddly the three candidate stars are in almost an exact line, which I drew for reference. And they are nearly equally spaced apart, 1525 pixels between the left and middle stars, 1563 pixels between the middle and right stars. Maybe they are actual stars and the lineup is just a coincidence, or maybe they are data artifacts. $\endgroup$ Sep 10 at 5:06
  • 1
    $\begingroup$ @anurag - The Apollo explanation is not just that it is daylight, but that the camera is not pointed solely at the dark sky. Same situation in this photo, although Apollo used film which works differently than digital, so the effect will be similar but not exact. When you say "no stars in the pic" do you mean the photo in the answer, or the full resolution photo that I linked to? In the full resolution photo there are three very sharp points of light that look like they could be stars, or maybe they are artifacts of some type but if so it is probably something other than dust or reflections. $\endgroup$ Sep 10 at 18:23
  • 1
    $\begingroup$ CMOS and film capture light in very different ways, so it's reasonable that they might behave differently with respect to extreme contrast. A film camera has to shorten the shutter time to prevent overexposure of the light parts of the scene, which means stars in the dark area don't get enough light onto the film to chemically change the silver iodide. But on a CMOS every pixel is "watching" all the time. There isn't really an 'exposure'. It's really about how much the amplifier circuit is doing. But that's why we have High Dynamic Range cameras now. $\endgroup$ Sep 11 at 15:02
2
+200
$\begingroup$

There seems to be two separate but related questions being asked, one is a simple yes/no question, are there any images of stars that have been taken from the Moon, and the same question for the Milky Way. It seems that you have received some answers to this question. But your specific choice of the words "starry night sky" and your additional question in the comments, "what does starry sky on Moon look like?" gives me the impression that you are looking for more than this, you seem interested in knowing what the view of the night sky looks like from the Moon compared to from the Earth. That is a great question, but I suspect that any photos that have been taken so far from the Moon will likely not answer this question very well, nor will photos taken with space telescopes in Earth orbit (and beyond). I will go into some details why because there are a lot of factors involved.

Scientific research of the universe is guided by specific objectives, and scientists look for the best ways to obtain information related to those objectives, independent of the experience that it creates for the observer. Not that scientists don’t also have human curiosity, in fact this is what leads many of them into a career in science in the first place. But all telescopes or camera instruments that have been sent into space or to the Moon so far have all been designed for specific types of scientific research.

This is why for example the majority of space telescopes observe in frequencies other than the visual spectrum, because in many cases this provides the greatest amount of data for the specific scientific objective, even though the images created are less relatable from a human experience perspective. The Hubble Space Telescope is one of the smaller number of space telescopes that observe in visible light, which is why the general public has been so enamored with the photos obtained by Hubble. But much of Hubble’s important research has actually been done in the near-infrared frequency, and you likely won’t see many of those images on wall calendars.

Hubble visible vs infrared Hubble visible light (left) vs infrared (right). Which of these is more likely to show up on a wall calendar or screensaver? (source: STScI)

Landers and rovers on the Moon and Mars have cameras that operate in visible light, but they are designed for surface photography not astrophotography. Not long after the NASA Perseverance rover landed on Mars in 2021 a photograph was widely circulated which purported to show a photograph of the Milky Way taken by the rover. However this was actually a composite photo done by a VR filmmaker. In the Snopes investigation of the photo they talked to someone at JPL who confirmed this:

the cameras on the rover do not have the capability to capture such a detailed photo of the night sky from Mars. The photo could have been taken from anywhere on Earth.

This may answer your question about whether any photos of the Milky Way have been taken from the Moon, however maybe someone who is looking into this specific part of your question will find some evidence confirming whether or not this is the case.

When it comes to the human experience of viewing the starry sky, the best results come from looking at the stars directly with our eyes rather than viewing photographs, even ones taken from space. I heard one astronaut say that the view of the sky from a high elevation in a remote part of the world in ideal seeing conditions is pretty close to the view of the sky from space. Anyone who has been fortunate enough to view the night sky from a very dark viewing location on a clear night will likely agree that it was a much more profound experience than any photograph can reproduce. This is because human vision is incredibly complicated and robust. And it’s not just about resolution. Instead of images being created on film, CCD or CMOS, the visual image that we see with our eyes is created in the brain in a very complex way, creating an experience which is very different than what can be captured in a photograph. The Cambridge in Colour article Cameras vs. the Human Eye gives a good overview of some of the differences.

Also our visual experience of the starry sky is more one of “panorama” than focus on specific objects, or smaller sections of sky as is more often the case with space telescopes. This is why many of the more relatable photographs of the Milky Way are from ground based cameras, not from Hubble, as spectacular as those are in their own way.

Hubble Milky Way Hubble Milky Way (source: NASA/ESA)

The Rising Milky Way over Uluru The Rising Milky Way over Uluru (photo by: Eddie Yip, source Wikimedia Commons, CC BY-SA 2.0)

A regular 35mm camera used on the Moon would likely create a more visually stunning photograph of the lunar sky than any of the scientific instruments that have operated there. The Apollo astronauts had 35mm and 70mm film cameras with them, but they were pretty busy during their EVA’s, they took a lot of photos of the Moon’s surface as well as documenting their activities, but unfortunately they didn’t have any leisure time available for astrophotography. Hopefully this will be an activity that future lunar explorers will engage in when Moon missions are of longer duration. Those photos will hopefully provide a better answer to your question "what does starry sky on Moon look like?" than the past and current instruments are capable of.

Although even then, the photographs that they produce will likely not be nearly as impressive as what you can experience yourself by making a trek to a dark sky location on a clear winter night.

$\endgroup$
8
  • $\begingroup$ In the absence of light pollution, any lunar lander/rover operating over the lunar night, on far side (thus avoiding both sunshine and earthshine) can capture spectacular view of the night sky with lunar landscape within the view. The fact that NO mission to the Moon has ever done this is strange. $\endgroup$
    – anurag
    Sep 10 at 15:53
  • $\begingroup$ @anurag - Do you believe that humans have landed on the Moon or sent probes to the Moon, or is this something that you are unsure of and this is one of the reasons for your question about photos of stars from the Moon? $\endgroup$ Sep 10 at 16:12
  • $\begingroup$ Scenario 1: I do not believe man reached moon; should that stop any crewed/uncrewed mission to the moon from capturing human perspective? Scenario 2: I do believe humans reached moon; then why has no-one bothered to capture human perspective from moon? I understand that such missions are expensive and thus have specific objectives, but, how hard is it to shoot the landscape with sky in sight during twilight? Besides, this specific answer on which I am commenting shows a starry sky pics from earth, is that even relevant? $\endgroup$
    – anurag
    Sep 11 at 5:58
  • $\begingroup$ @anurag Now I think you are being a bit... unreasonable. Nobody went to the Moon during twilight. Good sunlight was absolutely required for the scientific missions. You can ask new questions 1) "Earliest and latest times in the lunar day and lowest solar elevations for which the Apollo astronauts were present on the Moon?" and add the tag record, 2) "Why didn't the Apollo astronauts land at dawn or stay until sunset?" (but ask the first question first and use answers there to support your second question). $\endgroup$
    – uhoh
    Sep 14 at 23:08
  • 1
    $\begingroup$ @uhoh - Thanks! $\endgroup$ Sep 19 at 14:31

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.