4.1 Apollo 8
Apollo 8 is of significance because the astronauts on board became the first people to see the far side of the moon, and the first to witness an Earthrise: the apparent rising of the Earth from below the Moon's horizon as the orbiting spacecraft reached Mare Smythii in its passage around the Moon. This phenomenon had, of course, already been witnessed by Soviet and US unmanned probes, but to be captured by human eyes added more significance to the event.
The mission was launched on 21/12/68, reached lunar orbit on 24/12/68, and re-
ESSA 7 images are available in this document: ESSA 7 data catalogue. I actually own a hard copy of this and confirm that the online scan is absolutely accurate. ATS-
The full transcript of the mission can be found here: NASA link. The mission timeline is here: NASA link. The final section will look at the meteorological data available, to see how the photographic record compares with ground based measurements of the weather at the time.
4.1.1a Apollo 8 images – on the way to the Moon
While it doesn’t show the full Earth, the first images of interest to us are actually from the 16mm footage taken at the same time as the SIV-
Figure 4.1.2: AS08-
It is also taken very soon after separation from the Saturn IV-
It is also worth noting the shadow under the linear cloud mass near the terminator over north Africa (picked out by the green arrow). The direction of that shadow under the clouds is consistent with the sun's direction at sunset. It’s also obvious that the now moon bound craft has moved further East over the Earth’s surface, as we can now see the West coast of Africa. The 3D rendering of the digitally restored data is both spectacular and completely accurate.
We also have a 16mm still taken at around the same time, if we examine the amount of Africa visible it would appear to have been taken about 15 minutes after the still image (figure 4.1.4), and perhaps 90 minutes after the first sequence of Earth photos in magazine 16, taken shortly after TLI -
Figure 4.1.5: AS08-
Figure 4.1.6a: ESSA-
In this image, the long shadows are cast by the clouds over the Amazon, and the yellow & purple arrows point to the same weather systems as they do in the previous figure, although only the thin tail curling away from the yellow arrow system is still visible.
Much more prominent now are a large spiral system off the north American coast and below Alaska (green arrow), and the scattered clouds over the south Pacific. There is also a prominent plume of cloud heading northwards from Antarctica (magenta arrow), and a small whirl of cloud off south America (red arrow) that are all easily found on the satellite image, along with all the other weather patterns.
The Earth has rotated by a consistent amount between the first two photographs analysed, the shadows lengthen at the terminator, and the weather systems are still visible from the previous image. The bright spot showing the sun's reflection can be seen in this image, and the perspective of the photographer has changed noticeably, with much more of the Antarctic region in view.
Stellarium suggests a terminator time of around 20:45 on the 21st. The ESSA track over the terminator region was commenced at 17:00, as this was when track 2 (pass number 1593) began, as discussed for AS08-
It’s worth mentioning again that the 3D reconstruction superbly recreates the scene, and also that as the Apollo craft is now further away the rendering process in the software has had to change to make the view match. Sticking with the original rendering would require zooming so far out of the object to reveal all the detail at the edges it would be too low a resolution to be worth including. Figure 4.1.6b illustrates the point.
Figure 4.1.8: AS08-
Although there is no land visible in the image, it is possible to mark the position of the terminator with Stellarium by using the previous image analysis as a reference. The weather system highlighted by the green arrow is the same in figure 4.1.9 as in figure 4.1.6, which means that the terminator is just about on the west coast of the USA, which puts the time at around midnight on the 22nd. This corresponds well with the ATS-
Stellarium also indicates that Australia should be visible on the western limb. This part of the Apollo image is a little washed out, but the magenta arrow points to a band of cloud that should lie off Australia's east coast and that is visible in all 3 images presented here.
The presence of that green-
No specific mention of the actual time of the photograph, but the transcript does have the crew querying what settings they should be using on the camera, and stating at around 01:00 that:
012:06:27 Anders: This PTC attitude really isn't the greatest for taking pictures of the Earth.
PTC stands for 'Passive Thermal Control', or the 'barbecue roll' slow rotation that allowed the CSM to balance its temperature in direct sunlight.
As before, we have a pair of 16mms still for comparison (figure 4.1.10). While there is no apparent time difference between the first still on the left and the Hasselblad, there is a clear amount of rotation evident in the next still.
Figure 4.1.11: AS08-
Figure 4.1.12a: ESSA-
Figure 4.1.16: AS08-
The green and purple arrows in figure 4.1.15 point to the same systems shown in figure 4.1.17, and the thin swirls of cloud discussed previously are now clearly in view (red arrow). Similar thin wispy bands of cloud can be seen off the coast of south America (south of the cyan arrow).
For the first time in this section, an ATS-
ESSA's orbit best matching the terminator is number 1606 (track 2) which commenced at 18:05, just 55 minutes before the Apollo photograph, which Stellarium puts at 19:00.
Ostensibly, the ATS & Apollo images seem (terminator line apart) identical, but there are subtle differences. The clouds over the always dynamic Amazon climate system, for example, are in a different formation to Apollo's, where they are much more similar to the ESSA image taken nearer the time. There are also differences in the way the twin streams of cloud picked out in red are shaped. In ATS-
Also available at this time was a TV broadcast that took place at 20:01 on the 22nd. A still from this broadcast (available here) that briefly showed Earth is available in figure 4.1.17b, and as the people on the ground state in the broadcast it’s very over-
Figure 4.1.18: AS08-
As suggested previously, little has changed in the weather systems already shown, but it does serve to show (again) that the Earth is rotating as the CSM gets further away, and that that rotation brings into view weather systems that were previously hidden. There is no change in the ATS-
Stellarium suggests a time for the image of 21:30, just 90 minutes after the previous one, and all of the colours for arrows to identify weather systems in figure 4.1.17 apart from the green and red ones are used again. The reader is also referred back to figure 4.1.6, which showed the same view roughly 24 hours earlier, and where magenta is used to identify the same weather pattern. Those two day's weather patterns are compared below in figure 4.1.20.
Figure 4.1.20: AS08-
The two days’ images show what is obviously the same weather system, but that has developed over 24 hours to extend further northwards, while a frontal band to the west moves further eastwards towards Chile.
Next up in the sequence of images is AS08-
Figure 18.104.22.168: AS08-
The Earth has rotated sufficiently to lose the ATS-
The ATS image was actually taken at 22:43 on the 23rd, over 20 hours after the Stellarium estimate of the image time, and understandably there is a much bigger difference between the Apollo image and ATS-
Of those systems, the most striking ones are at the northern and southern ends of the planet. In the north there are the two frontal bands (green and red arrows) marking the boundaries of lighter swirls of cloud between them. To the south there are the storms heading north from the Antarctic, including the striking tight curl of cloud marked by the yellow arrow, and the long band of cloud making its way to Australia's east coast.
ESSA is a much better match for the Apollo image, and this is explained by the images being taken much closer in time to it. Orbit number 1609 (track 5) is the closest to the terminator, and commenced at 23:00 on the 22nd.
The next image of Earth we have is extremely significant because it comes not from images presented after the fact but from a live TV broadcast.
As part of their journey, the Apollo 8 crew made a number of short live TV broadcasts to Earth. The first broadcast on the 22nd did show Earth but was overexposed, though photographs from it did appear in the following day’s newspapers. The most famous of the broadcasts is the Christmas Day broadcast made while rounding the moon, in which the crew took turns to read out a number of verses from Genesis. Clips from these broadcasts are viewable at the Honeysuckle Creek website.
Two clips from the Honeysuckle Creek website are of interest, as they show images of Earth. The 2nd TV transmission shown was carried out at 19:53 on December 23rd, and it is possible to capture a screenshot of the Earth from that and compare it with the ESSA 7 and ATS-
Figure 4.1.31: AS08-
While Christmas day 1968 is the very latest that the picture could have been taken, the satellite record places the photograph very definitely on the 23rd, with Stellarium placing the time at 21:00 on that date. ATS-
It’s also very obviously the same view that can be seen on the TV broadcast images, the only difference being that a substantial chunk of South America has slipped into darkness.
Looking at the Apollo photograph, they are describing accurately what they can see, and have not (as in all cases when discussing the view of Earth on any mission) been prompted in any way. The long cloud heading north-
The next images from Apollo 8 are from lunar orbit. Click the buttons below to navigate there or elsewhere.
Figure 4.1.14: AS08-
As usual, the weather patterns on the satellite images correspond exactly with those on the Apollo image, and several of the cloud systems visible in this image will be seen in later ones, not least the spectacular 'dog-
Although the Apollo image is slightly out of focus, it is still possible to pick out the thin clouds over north Africa (eg the cyan arrow), the coastal cloud banks around southern Africa, the typical frontal system off South Africa itself (yellow arrow).
The astronauts themselves describe the view to the ground at exactly the same time as this image was taken:
025:12:41 Borman: This is a mighty nice view we have down there today. A little bit more than a half-
Stellarium suggests a time of around 14:00 on the 22nd for this image. ESSA's nearest track to the terminator is track 11. This is orbit number 1602, which is labelled as the first orbital pass on the image dated the 22nd, and was commenced at 10:05 on the 22nd. The ESSA satellite would barely cover the area around the terminator before the Apollo image was taken, never mind the rest of the photograph.
It’s worth mentioning here that there are Corona passes available for this image, but as none of the areas actually feature any cloud there isn’t much point in introducing them to the discussion. The new digitally recovered and modelled ESSA data, however, is very obviously a perfect match.
The next image in the magazine, AS08-
Figure 4.1.21: AS08-
Figure 4.1.22: AS08-
We’ve now moved on a couple of hours, and the Rocky mountains are beginning to disappear into night. There is no direct reference to the photograph being taken, but roughly an hour later communications issues led to Hawaii being asked to send messages, suggesting that the Pacific view in the photograph is consistent (as we would expect) with the mission narrative.
The area shown is an intermediate one between those covered by ATS-
As the time suggested by Stellarium is 23:30. The ATS-
ESSA’s image is a much better match than either of the ATS satellites, as its orbital pass is much closer in time. The closest pass to the terminator is number 4, or pass 1608, which started at 21:05.
The next image of Earth is AS08-
Figure 4.1.9: ESSA 7 (left) and ATS-
Figure 22.214.171.124: ESSA-
Figure 4.1.1: Composite of several screenshots from Apollo 8 16mm footage.
Comparing this with the ESSA mosaic is a relatively straightforward business once it is realised that the film sequence used in the original video is the wrong way round -
More importantly, the Earth orbit insertion at 13:00 on the 21st was still several hours before this area was covered by the ESSA satellite. There is no ATS image for this date, but the evidence from ESSA clearly matches the Apollo video. The fact that it is a moving image, not a static photograph and complete with lumps of space hardware spinning in micro-
It’s also worth mentioning that the TLI burn was observed from Hawaii. Separation was 25 minutes after this, and this would put the Apollo 8 ship exactly where it appears to be in the film. 15 minutes after separation we have these comments:
003:35:44 Borman: We see the Earth now, almost as a disk.
003:35:59 Lovell: We have a beautiful view of Florida now. We can see the Cape, just the point.
003:36:05 Collins: Roger.
003:36:06 Lovell: And at the same time, we can see Africa. West Africa is beautiful. I can also see Gibraltar at the same time I'm looking at Florida.
Which shows they are exactly where they should be.
A little after this we have the images of a full Earth in Hasselblad magazine number 16. This magazine is notable because it contains images from all stages of the mission from initial low earth orbit, separation of the Saturn IV-
Stellarium (an astronomical software package used to identify the location of celestial bodies: http://stellarium.org) can be programmed with times and locations. In this case, using the lunar surface as a view and changing the date to the 21st gives a time for the Apollo image of around 17:15 and 17:30 for the 16mm still, shortly after the initial separation from the SIV-
004:36:00 Anders: … it's a beautiful view with numerous cloud vortex
As well as Borman commenting that
004:37:15 Borman: I can still see the Cape and isthmus of Central America.
ESSA 7 data suggest that South America would have been photographed by the satellite at about 19:09, as this was when track 3 (pass number 1594) of the satellite's daily orbit over it was commenced. The time over the terminator area would be more covered by track number 1, orbit 1592, which commenced at 15:05. At the time of the Apollo image, then, it would be another 2 hours before the satellite would image the area photographed, and there would be a further few hours on top of that before all the visible Earth was covered.
The next in the series of images taken showing any significant change in the scene below them is AS08-
Figure 4.1.4: 16mm still, (top left) with the terminator around Africa compared with that from figure 4.1.1, and a Stellarium estimate of time at terminator. Below centre and right is AS08-
Again, there would seem to be about a 15 minute time difference between the two. We also get a report from the transcript that:
008:24:29 Anders: …Sure got a nice view of the Earth from here. We can see Baja California and about where San Diego ought to be.
Which is pretty much bang on the money.
The next frame in the magazine we have another view of a still more rotated Earth, and this time it has moved far enough to allow an image from ATS-
Figure 4.1.7: Comparison of 16mm still with Apollo image from figure 4.1.5.
Figure 4.1.10: 16mm still taken at the roughly the same time as the image in figure 4.1.8
A few hours later, we have the next image of Earth showing movement, AS08-
A couple of images later in the magazine we have another new image of Earth, this time showing Africa as the dominant land mass in view. AS08-
Figure 4.1.13: 16mm still image taken at the same time as figure 4.1.11
Figure 4.1.5: Honeysuckle Creek interpretation of terminator position during live TV broadcast
Figure 4.1.26: Live TV screen capture compared with ESSA 7 image from 23/12/68
The TV image is overexposed, but weather systems in both Hemispheres are easily identifiable. The broadcast of Earth from space made headline news around the world, but two interesting front pages are from the Long Beach Independent and Minneapolis Tribune of 24/12/68. Figure 126.96.36.199 shows these front pages, with the same weather systems in 4.1.26 identified (only one image has been arrowed for the sake of simplicity).
The newspapers were published on the 24th, and therefore can only have been taken from the TV broadcast on the 23rd. It could not have been produced from ESSA satellites imagery as the image for the 23rd would not have been completed until the 24th, by which time the newspapers would have been in production. The TV image can only have been broadcast from space on the 23rd. The ATS-
Another image is also available of the TV broadcast in the form of the image shown below (figure 4.1.28), available from the Facebook site Retro Space Images.
Figure 4.1.28: Mission Control during the TV broadcast of 23/12/68
A zoomed and cropped image of the large monitor screen (figure 4.1.29) shows that the image on the screen (and on every monitor visible) is the same as the one on the newspaper front page, which, in turn, is an exact match of the satellite photos from the same date.
While broadcasting the view, Lovell describes the view to Capcom Michael Collins:
055:10:28 Lovell: What you're seeing, Mike, is a -
055:12:17 Lovell: Okay. For colors, the waters are all sort of a royal blue; clouds, of course, are bright white; the reflection off the Earth is -
055:19:25 Lovell: …I can pick out the southwest coastline of the Gulf and where Houston should be, and also the mouth of the Mississippi; I can see Baja California and that particular area. I'm using a monocular which we have aboard.
Unsurprisingly, this is an entirely accurate description of what is evident from the satellite photographs.
For the next still view of Earth we return to magazine 16. AS08-
Figure 4.1.29: Zoomed & cropped image from the mission control photograph in figure 4.1.28. Colours as in figure 4.1.26
We also have TV footage of mission control during this TV broadcast (Moon Machines), and if we look carefully we can see the same TV broadcast can be seen on a monitor, with the same clouds – see figure 4.1.30, and we can also include a newspaper page or two showing the scene to prove when it was done.
The rotation of the Earth in this photograph compared with the previous one is such that the ATS image no longer has any features that are visible in it, and the only weather system identified in the previous image that is also identifiable in this one is the one picked out by the magenta arrow.
The system picked out by the blue arrow in figure 4.1.9 can still be seen on the satellite image, just as the green arrow here identifies a weather pattern that was visible on the ESSA part of figure 4.1.9, so it is obviously a continuation of the weather observations on the day. The plume of cloud extending up from Antarctica (yellow) is very easy to pick out in the Apollo image, as are the streams of west trending clouds to the west of it (purple and cyan arrows), the 'Y' shaped pattern near the equator (red arrow), and the Himalayan clouds (blue arrow).
Stellarium shows that the terminator is showing a time of approximately 07:00, and this can be compared with an ESSA time for the orbit nearest the terminator of 02:05 (orbit 1598, track 7).
An interesting feature of this particular Apollo 8 image is that it was taken while a US Corona satellite was in operation.
Corona satellites were relatively short lived spy satellites launched to photograph enemy installations and troop movements. The film canisters were fired from the re-
One of the satellite passes is covered here in the context of showing how many passes you would need to get the same images taken by Apollo. On this image we have three areas we can examine. The first is over the coast of north Korea and China, and I’ve shown it below in figure 4.1.12b.
Figure 4.1.12b: AS08-
It’s worth pointing out a few caveats here before drawing any conclusions. We have no real idea when these images were taken other than the date, and there are very few clues available to us as to what time of day it might be. The lack of shadows on the ground suggests that the sun may well be high overhead in late morning/noon, and as the next orbital swathe available shows shadows indicative of early afternoon this doesn’t seem too far out. The Apollo image was taken at 07:00 GMT, but this translates to much later in the day in the image. The local sunset time for North Korea at this time of year is around 17:00, or 08:30 GMT, so the Apollo and Corona images could be separated by as much as 6 hours.
Another thing to consider is whether I’ve accurately worked out which location is being shown in the image given that most of the coastal area that would help us identify it precisely is under cloud. We do, however, have the ESSA satellite image that shows us coastal outlines, and this helps us to confirm that the clouds skirt around the Korean peninsula, and we do have the location correctly identified.
What the Corona image identifies is an area of clear skies off the east coast of North Korea, with a similar gap between the clouds that next to this gap and the coast to the north. The Apollo image shows a similar pattern.
A couple of orbits later and Corona begins a pass over China that ends just east of Hainan Island. Close examination under the clouds on land show shadows angled slightly towards the terminator suggestive of a photograph time of late morning/early afternoon. Figure 4.1.12c shows the details.
Figure 4.1.12c: AS08-
Again it’s worth bearing in mind the time gap between the two images, but as with the previous Corona pass the broad details are confirmed: the thick swathe of coastal cloud, some thinner bands just inland, and some lighter bands of cloud to the north.
The final pass visible in this image covers two sections stretching from Kazakhstan in the north to the Nepalese border in the south, as shown in figure 4.1.12d.
Figure 4.1.12d: AS08-
In this case the main feature in the Corona image is the large ‘C’ shaped cloud over Kazakhstan, and this feature can also be seen at the top of the Apollo image.
Also accompanying the Apollo still is a 16mm equivalent to the still image, and as with the previous image there is no apparent time difference between the two (figure 4.1.13).
Figure 4.1.27: Front pages of the Long Beach Independent (top left), Minneapolis Tribune (top right), Toledo Times (second row left), New York Times (second row right), Pittsburgh Post Gazette third row left) Peoria Journal Star (third row right), the Daily News (fourth row left) and the Daily Telegraph (fourth row right), Evening Capital (fifth row left), Daily Mirror (fifth row right), Philadelphia Daily News (sixth row left), Chicago Tribune (sixth row right top) and Roseburg Oregon News Review (sixth row bottom). Row 7, Daily Express (left), Globe and Mail (right). Row 8: The Patriot, Chicago Tribune, Yorkshire Post.
Figure 4.1.30: Mission control during Apollo 8's TV broadcast (left) and newspaper pages from the next day (above left and right)
Figure 4.1.3: ESSA-
Figure 4.1.6b: Earth viewed using the same projection method in figure 4.1.4 at different virtual distances. The image on the right is from the same shot shown in the centre.
At first glance these are the same, but a closer look shows that there is more of the Antarctic on display, and weather patterns on the western limb are more clearly in shot. This is exactly what you would expect if you were observing Earth from a real space ship moving further away from our home planet, and exactly what happens in the Apollo images.
Figure 4.1.15: ESSA-
Figure 4.1.17a: ESSA-
Figure 4.1.19: ESSA-
Figure 4.1.32: ESSA-
A short while after AS08-
Figure 4.1.17b: Still from live TV broadcast on December 22nd and a newspaper front page dated December 23rd.