4.1.6 - Day 6: December 26, 1968

Safely on their way home the crew eventually continue their Earth photography, with the next series occurring after a few pictures of an increasingly distant Moon (images AS08-15-2543-7 were mistakenly labelled in the Apollo Image Atlas as the Earth!). The first high quality image of the sequence is AS08-15-2550 (the preceding two show the same view but are not as zoomed in). This photograph is shown in figure 4.1.6.1, and analysed in figure 4.1.6.2.

Figure 4.1.6.1: AS08-15-2550. High quality source: AFJ

Figure 4.1.6.2: ESSA-7 (left) and ATS-1 (right) compared with AS08-15-2550 and SkySafari time estimate.  Left, digitally recovered ESSA data from the NSIDC superimposed on a colour Earth map in Blender3D.

In this photograph, nearly all of the weather patterns visible in the previous picture have disappeared beyond the terminator, with the exception of the one identified by the blue arrow. In its place are the complex weather patterns dominating the south Pacific around Australia. It is fairly obvious that the long band of cloud to its north (magenta arrow) around the Hawaiian islands and those to the east (red arrow) and south (cyan arrow) are present on ESSA's image as they are in Apollo's. The cyan arrow points to a system south-west of Alaska. Alaska itself would be at around sunset at this time. By way of confirmation, at around 02:00, Michael Collins, acting as Capcom, tells them:

109:19:27 Collins: I don't know how much detail you can see, Jim, but your sub-spacecraft point is out in the middle of the Pacific Ocean about halfway between Australia and South America

The ATS-1 image also shows the red and magenta arrowed systems clearly, although the fact that it was taken several hours before the Apollo photograph means that there are differences in their configuration.  For example the yellow arrow points to a cloud mass that is much more separated from the clouds picked out by the blue arrow in ATS than it is in Apollo.

The green and cyan arrows in the ATS image point to where cloud masses are, but aren't quite as easy to see as they are on the ESSA and Apollo images.

As SkySafari identifies the time as being at around 03:30 on the 26th and confirms the sub-spacecraft position. ATS-1's image used is from the 25th (22:41 GMT), as this is nearer in terms of elapsed time between the satellite image and the Apollo one. ESSA's orbit at the terminator is number 1647 (track 6) which was commenced at 00:09 on the 26th.

The next mini-sequence of images in magazine 15 is represented by AS08-15-2554, and Australia is much easier to see in this one. It can be seen below in figure 4.1.6.3, and analysed in figure 4.1.6.4.

Figure 4.1.6.4: ESSA-7 (left) and ATS-1 (right) images compared with AS08-15-2554 and SkySafari time estimate. Left, digitally recovered ESSA data from the NSIDC superimposed on a colour Earth map in Blender3D.

Australia has now come into view properly and we can see the development of the weather systems identified in AS08-15-2535. The magenta system in this image is the same one that wrapped itself more closely around the north and eastern coasts 24 hours previously, but has now moved on towards New Zealand leaving the coast clear.

For this image, we can see that the magenta, cyan and red arrows point to systems that are visible on the same ATS-1 image (dated the 25th) as used previously. The blue and purple arrows identify systems that are just visible near the north-western horizon but were not specifically picked out in the previous figure.

The 'plume' system looks very similar, and there is still a hint of the coiled frontal 'bass clef' system to the south and west of the continent. Closer examination of the satellite images shows that in fact the plum has been joined by what was the clef, which has rotated and moved south and east. The system to the west is a new system moving eastwards from off South Africa.

ATS-1's time has already been noted, but the ESSA orbit best matching the terminator is orbit 1648 (track 7), which commenced at 02:05.

A short while later, images are taken showing Australia's east coast passing into darkness, as shown in AS08-15-2562 (figure 4.1.6.5) and analysed in figure 4.1.6.6. The images between the previous photograph and this one consist of poorly framed images of Earth taken at the same time as AS08-15-2554.

Figure 4.1.6.5: AS08-15-2562. High quality source: AFJ

Figure 4.1.6.6: ESSA-7 image compared with AS08-15-2562 and SkySafari time estimate. Left, digitally recovered ESSA data from the NSIDC superimposed on a colour Earth map in Blender3D.

In this latest instalment, Australia's east coast is now well beyond the terminator, but the new frontal mass off the west coast (green arrow) is easy to make out. The purple arrow points to the long cloud bank identified by a blue arrow in the previous analysis, which joins up to landmasses over the Indian subcontinent and the Himalayas.

It is also easier to see in this image the transformation of the cloud marked by the cyan arrow from an elongated curl off the west coast on the previous day to the more compressed form it has on the 26th. Although not specifically labelled, it is worth noting the wide band of sub-equatorial cloud north of Australia, is it also appears in the next image showing the continent.

SkySafari puts the terminator at about 09:30 on the 26th ESSA's terminator orbit is number 1649 (track 8), which commenced at 04:00 on the 26th.

Figure 4.1.6.7: AS08-13-2369. High quality source here: AFJ

Figure 4.1.6.8: ESSA-7 images dated 25/12/68 (right) and 26/12/68 (left) compared with AS08-13-2369 and SkySafari terminator estimate. Left: Digital 3D reconstruction using recovered ESSA data from the NSIDC superimposed on an Earth map in Blender3D.

As this photograph shows the exact region where the dividing line between days for ESSA mosaics is placed, ESSA images dated the 25th are used to discuss the areas east of that line, and dated the 26th for areas west of that line.

Describing the scene where Africa dominates is always tricky in terms of relating it to ESSA images because of the mosaic dividing line. This image does, however, show clear differences in the weather systems either side of that dividing line that helps make it simpler. It’s also worth taking a look at the 3D model, in which I’ve used the correct sections of each day’s image to produce a single globe. East of the divide, the green arrow (which is the same weather system identified with that colour in figure 4.1.50) points to clouds that show a definite difference on the image dated the 25th compared with how it looks on the image dated the 26th. Likewise the blue arrow and cyan arrows point to systems east of the divide look very different compared with the west side.

The red arrow points to a front on the western side of the divide, and if this system is compared with the one shown on the ESSA mosaic dated the 25th, he central blob of cloud shown in the latter is missing, and it is also not far enough to the east compared with the image dated the 26th.The thin line of cloud crossing the Apollo image over the southern Sahara towards Arabia (purple arrow) does not show as clearly on the ESSA mosaic dated the 25th.

The data catalogue for ESSA shows that the images dated the 25th consist of orbits 1640-1652, while the ones dated the 26th are 1652-1664, so the last orbit on the  mosaic dated the 25th is the same as the first orbit on the mosaic dated the 26th (the line on the latter is clearly further east). The time for orbit 1652 is given as 10:05 on 26/12/68, which is roughly 3 hours before the SkySafari suggests the Apollo image was taken.

There is a colour image showing almost the same scene in magazine 15, AS08-15-2563, and this is shown below in figure 4.1.6.9, along with a zoomed and cropped image of the Earth from that image. Ostensibly this image looks identical to the one from magazine 13, but there zooming in on the terminator does seem to indicate a difference (figure 4.1.6.10).

Figure 4.1.6.9: AS08-15-2563, with a zoomed and cropped Earth from that image and 3D model from digitally recovered ESSA data. Source

Figure 4.1.6.10: Arabia as seen in AS08-13-2369 (left) and AS08-15-2563 (right), with SkySafari time estimate for the colour photo.

The weather systems are very much the same, so it is obviously taken on the same date, but it does appear that the Arabian landmass is closer to the terminator in the colour image compared with the black and white. The amount of rotation is consistent with a time lapse of about 15 minutes between them, as shown by SkySafari. However, Skysafari also suggests that there should be cler blue water on the western edge of Saharan Africa and that doesn’t seem to be the case, so we could just be looking at the difference in resolution afforded by the two types of film used.

Several photographs of the same scene were taken in magazine 15, and the next photograph showing a different view in magazine 15 is AS08-15-2574. This is shown below in figure 4.1.6.11 and analysed in figure 4.1.6.22.

Figure 4.1.6.11: AS08-15-2574. High quality source here: AFJ

Figure 4.1.6.12: ESSA-7 image compared with AS08-15-2574 and SkySafari terminator estimate (left). Above right: Digital 3D reconstruction using recovered ESSA data from the NSIDC superimposed on an Earth map in Blender3D.

Despite Africa having moved its relative position by some distance between this photograph and the one used previously, most of the weather systems available for comparison are still visible. The magenta, purple red and yellow arrows all point to the same weather systems identified in figure 4.1.6.8. The time of the image is put by SkySafari at 15:45, and this time lapse has allowed the front identified by the red arrow to change its position in comparison with figure 4.1.6.8, and it appears much less solid than before. The ESSA orbit for the terminator here is track 12 (orbit 1653), which commenced at 12:00 on the 26th.

As with the preceding image, a different magazine shows an almost identical view. Magazine 14 has photograph AS08-14-2509, which appears after several photographs of the entire Moon through red and blue filters. This photograph is shown below in figure 4.1.6.13, together with a zoomed and cropped Earth from it.

Figure 4.1.6.13: AS08-14-2509 with zoomed and cropped Earth from it with a comparison 0f the terminator area from AS08-15-2574. High quality version here

Again there is evidence that the two images, although very similar, were not taken at exactly the same time. If the area around the terminator over Libya is zoomed in on, the terminator line seems marginally different. Of the two, it appears that AS08-14-2609 was taken slightly later than the one from magazine 15, but again it could be differences in the film used. The cloud masses over the Mediterranean to the north are clearly nearer the terminator in magazine 14's contribution, as is the dark spot on the terminator that is Libya's Haruj volcanic field.

It's also with noting the shadows cast by the long clouds in central Libya between and the Tassilie n Aljer desert area and the Haruj, which are entirely consistent with a sunset time period. Once again we have a situation where two apparently identical photographs are not, purely because the Earth is moving while the astronauts return to it.

The next shot of Earth is a return to the 16mm footage. This time we have a pan of the Earth taken through the CSM’s sextant, and by piecing together individual frames we can get a view of the whole disk (figure 4.1.6.14).

Figure 4.1.6.14: Montage of screenshots from 16mm footage compared with ESSA satellite mosaics dated 26/12/68, with SkySafari estimate of terminator at time of filming. Left: Digital 3D reconstruction using recovered ESSA data from the NSIDC superimposed on an Earth map in Blender3D.

The weather systems are evidently those shown in the ESSA image, but how can we be certain that the image was taken at 16:55 on the 26th, particularly as the most reliable indicator of time (the terminator) is obscured? We can get an approximate timeframe for the image by comparing it with figure 4.1.6.12 (AS08-15-2574)  has been determined as 15:45, as we can see the same weather systems identified in it.

This gives us a good start, but more reliable still is the mission report and mission transcript.

"For this flight, a special adapter allowed the 16mm sequence camera to be attached to the command module sextant"

allowing for colour filming.

"During transearth coast, sextant photographs were taken of the Moon at about 123 hours and of the Earth at 124 hours. Although the range is too great for accurate horizon analysis, the appearance of the Earth through the red tinting of the landmark line of sight should be an effective familiarisation aid for future crews."

The video footage immediately before the Earth shot is of a reddish tinted Moon, there is a reddish cast to the Earth in the montage, and the circular border would be that of the sextant. The exact timing, and the time used in the Stellarium image, is confirmed in the transcript. At 5d4h4m, or 124:04 hours MET, or 16:55, we get the following comment in response to a request from Capcom to change the CSM orientation:

124:04:16 Borman: That's fine. We are going to stay in for about two more seconds while Jim takes the pictures through the sextant for the optics people.

Is the time correct? The answer is obvious from the landmasses visible in the montage. South America is in shot on the western limb, with the Pacific ocean off Chile just discernible west of the cloud mass arrowed in green. The west coast of north Africa is just visible on the eastern edge of the picture, but the remainder of the continent (and the terminator) are hidden by the sextant’s edge.

The next views of Earth mark a return to TV.

The second TV broadcast examined here is the 6th TV transmission, which started at 20:36 on the 26th, some 3 hours after the ESSA track was taken, finishing transmission at 20:56. Earth was featured towards the end of that broadcast. The ESSA image is presented with a screenshot from that broadcast in figure 4.1.6.15a. 4.1.6.15b shows wire images for the press that clearly identify the date of transmission. Figure 4.1.6.15c shows newspaper pages dated the following day.

Figure 4.1.6.15a: ESSA-7 image from 26/12/68 compared with TV broadcast from the same date.

Figure 4.1.6.15b: Press wire photograph from 26/12/68 showing TV image from the last TV broadcast (Image is from eBay, copyrighted Historic Images) together with my personal copy of the same image. Both images are upside down.

The press images are centred on South America, and there is a clearly defined band of cloud along the east coast. The upper left of the image is North America, most of which is obscured by clouds.

The terminator line is just crossing Brazil, and SkySafari confirms that this is exactly where the terminator should be. While the TV screenshot is not as sharp as the Apollo photographs, and much of the ESSA clouds are not as clearly visible as those on Earth, it is still possible to discern unique systems that mark it out as having been taken specifically on the 26th, notably a small system off the coast of New York (identified with the blue marker) that is not there on the 25th.

We also have some crew description of the view:

128:02:11 Lovell: Well, the Earth looks a little bigger to us today, not much, but it's somewhat bigger. I'm sitting over in the right hand seat now; Bill           has got the TV camera; Frank is helping him out aiming it directly to hit the Earth. I hope we have a good picture. Can you see the clouds?

128:02:28 Carr: Affirmative. We sure can. Move it up toward the terminator - correction, away from the terminator just a shade.

128:02:38 Lovell: At the tip of South America, there is a great swirl of clouds down there. It looks like a great storm. I wonder if you can see it.

128:02:45 Carr: Roger. We see a large swirl just south of the terminator.

128:02:52 Lovell: Roger. And then up to the left hand side, or towards the north, we can see the light waters around the West Indies, and we can         actually see Florida. I'm looking through Bill's monocular, and I can see the various land masses, South America and the central part and southern part        of the United States.

And a short while later

128:19:57 Lovell: Roger. I just got on the sextant and now looking at Texas, and the weather man is right, it looks like a pretty good day. Full of clouds         down there, but not bad.

128:20:06 Carr: Real fine, Jim. Can you see the kids out in the yard waving?

128:20:14 Lovell: Would you tell Pete Conrad to get his kids off my roof?

128:20:16 Carr: Wilco. [Pause.]

128:20:22 Carr: Jim, do you see the bright spot out in the Pacific Ocean through the sextant?

128:20:31 Lovell: I'll try. We saw it, of course, through the windows and through the monocular. I'll see if I can spot it

As with the previous TV broadcast, we have a passage of time that should just be enough to detect rotation. Let’s see (figure 4.1.6.16).

Figure 4.1.6.17: AS08-15-2576. High quality source here: AFJ

Once again we have a duplicate image from magazine 14, AS08-14-2518. This image is shown below in figure 4.1.6.19, together with a zoomed and cropped Earth from it. On this occasion there is no obvious difference in the relationship of the various land masses and cloud patterns to the terminator, although comparisons are not helped by the out of focus nature of AS08-14-2518.

Figure 4.1.6.19: AS08-14-2518 with zoomed & cropped Earth from it. High quality source here: AFJ

This view of south America is unique, compared with the same view from other days, and your there are no weather systems in it showing the same configuration as previous ones of south America. The time is now 21:00 in the 26th, and ESSA's orbit for the terminator would have been carried out at 17:05 (track 2, orbit 1656).

That’s it for day 6, click  the link below for day 7.

Figure 4.1.6.18: ESSA-7 image compared with AS08-15-2576 and SkySafari time estimate. Left: Digital 3D reconstruction using recovered ESSA data from the NSIDC superimposed on an Earth map in Blender3D.

Figure 4.1.6.15c: Press images dated December 27th. Top row: Washington Post front page (left), New York Times (right). 2nd row: Daily News image (right), San Antonio Express (left) 3rd row:  Left, Herald Examiner, right: Chicago Daily News. 4th row: Washington Daily News (left), La Provincia (right). Dutch examples are from delpher. Left, Long Island Newsday.

Is there something I’d bet my house on? Maybe not. Is there something consistent with what we’d expect? Yes, there is.

Regardless of detectable rotation. all of the features can be made out in the press photos, and all of the features are much clearer in a still photograph taken at around the same time. That image is AS08-15-2576, which is shown below in figure 4.1.6.17 and analysed in figure 4.1.6.18.

Figure 4.1.6.16: comparison of start and finish views of Earth with SkySafari times.