More images of Kounotori (HTV) 7

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The image above is a stack (combination) of six images, taken at 10-second intervals with a 5-second exposure (Canon EOS 60D + EF 2.0/35 mm, 800 ISO). It shows Kounotori HTV 7 (2018-073A), a Japanese cargoship on its way to the ISS launched on September 22. This image was taken some 17 hours before it berthed to the ISS.

The cargoship was about 1m 38s behind the ISS at the time of observation. As no recent orbital elements were available, I did not know where to expect it relative to the ISS, so I started watching well before the ISS pass, and next noted it ascending over the roof just after the ISS had disappeared in Earth shadow.

The HTV 7 spacecraft was very bright during this pass: near magnitude +1, and a very easy naked eye object. Just like the day before (see an earlier post), it flared brightly, to at least mag -1/-2 at 19:50:18 UT (26 Sep 2018). The flare can be seen on the composite image above, and on the single image from this series below:

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Also note the distinct orange colour of the trail, which is due to the fact that HTV 7 is wrapped in gold-coloured insulation foil.

The flare happened while HTV 7 was passing through the field of view of my video setup:

The image below is a composite of the images taken while the ISS passed, and the images of HTV 7 passing 1m 38s later (i.e., they didn't move this close in the sky in reality!). The orange colour of HTV 7 stands out. Also well visible is that HTV 7 was somewhat faster than the ISS, due to a difference in orbital altitude (and hence orbital period):

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Imaging a pass of Kounotori (HTV) 7 on it's way to the ISS

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On 22 September 2018 (and after several launch delays, amongst others due to a typhoon), at 17:52:27 UT, Japan's Space Agency JAXA launched Kounotori (HTV) 7, a cargoship destined for the ISS. It will dock to the ISS tomorrow on September 27th.

The 9.8 x 4.4 meter HTV (HTV stands for "H-II Transfer Vehicle". The name Kounotori stands for "white stork") are easily visible, bright objects with a distinct orange colour due to the use of gold-coloured insulation foils.  See the image below of HTV 7 being assembled at the Test and Assembly Building at Tanegashima Space Center before launch:

image: JAXA

After days with bad weather, the sky cleared yesterday. I had a low pass in the southwest near 19:18 UT (Sep 25) and went to the nearby city moat with my camera, as I have a better view lower at the horizon there. Some whisps of thin clouds still lingered in the sky.

First, at 19:04 UT, I watched HTV 7's destination, the International Space Station (ISS), sail past as a very bright object. The image below is a stitch of two image stacks (!): one stack of two images, and a stack of 4 images with the camera FOV shifted horizontally. Camera: Canon EOS 60D with an EF 2.0/35 mm lens. I used exposures of 4 seconds at ISO 800.

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Then  I waited for HTV 7. As the latest orbital elements at that point were almost a day old, I was not sure about the exact time it would show up.

Some 14 minutes after the ISS it emerged, clearing the trees and houses low at the southwest horizon, and to my surprise and joy featured a bright flare to at least magnitude -1. My first image just captured the end of this brief flare (first of the two images below):

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The object was easily visible with the naked eye and had an orange hue. The image stack below was made of 5 images taken at 10-second intervals, with each image a 4-second exposure (camera details the same as for the ISS image). It shows HTV 7 from the bright flare to the moment it disappeared in the Earth's shadow:

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