Wednesday, 29 April 2015

KH-11 USA 224 recovered

Over the past week I twice tried to recover the KH-11 CRYSTAL ('Keyhole') USA 224 (2011-002A) but failed. Leo Barhorst and Cees Bassa however did recover it on the night of April 27-28, in an orbital plane which is 4 degrees more westward than its previous plane. This meant that on two previous nights when I was doing a 1.5-hours (one orbital revolution) photographic coverage of the old plane, it actually passed outside the FOV of my camera...

Last night, based on Cees' search orbit, I did observe it as it was passing through Lyra around 22:57 UT. The image above and below shows it, together with the old Japanese scientific satellite Tansei 3 (MS-T3, 1977-012A), which was captured as a stray in the same images. The Japanese satellite is moving in a much higher orbit, as can be seen from the much shorter trails. It slowly faded in and out, so it appears to be slowly tumbling.

The image below is a stack of 13 images (4 seconds exposure each, with 5-second gaps). The image above at the top of this post is a single image from this series. The images were made with the very fine Samyang 1.4/85 mm lens.

The plane change was probably done to keep the separation of this primary East plane KH with the primary West plane KH (USA 245) near 48-49 degrees (the angle between the primary East and West planes maintained over the past several years). This would also bring the separation with USA 161, the secondary East plane KH, to 25 degrees, similar to the current distance between the orbital planes of  USA 245 and USA 186 in the primary and secondary West plane.

I therefore expect that when we recover USA 161, the secondary East plane KH, it will be in an orbital plane about 25 degrees east of USA 224.

Thursday, 16 April 2015

Movie: Dragon CRS-6, The Twilight Saga!

Yesterday I did a very successful series of observations on the just launched SpaceX Dragon CRS-6, the Falcon 9 upper stage, and the two ejected solar panel covers, all still very close together at that time, 20 minutes after the launch. See the series of photographs in my previous post.

(movie is HD, click on it to enlarge: this small window will not show it well)

Today, 15 April 2015,  saw successful observations of the Dragon CRS and the Falcon upper stage again. At 19:00 and 19:02 UT (21:00 local time, Apr 15), in very deep twilight, I observed both objects during a near-zenith pass from Leiden. Using the movie function of my Canon EOS 60D, I shot the footage above (enlarge it to full screen - it is in HD- otherwise the two objects will not be well visible).

The sun was at an altitude of only -4 degrees, the sky was still bright blue with barely a star visible (only Venus and Jupiter could be clearly seen). Yet both the Falcon r/b and the Dragon CRS could be easily seen once past culmination and descending towards the east. They were both in the negative magnitudes, due to a very favourable phase angle and short observing distance. They were very fast too: it was quite a spectacular sight!

Both objects passed with a separation of about two minutes in time. The B-object, which is probably the Falcon r/b, was first. The A-object wich is probably the Dragon CRS-6 was next. Both objects were steady in brightness.

I also tried to observe the next pass at 22:34 local time (20:34 UT) but thick cirrus clouds had filled the sky by then. I did see a hazy ISS pass at 20:16 UT but the Dragon of Falcon were not seen.

Wednesday, 15 April 2015

SpaceX Dragon CRS-6 and debris pieces, twenty minutes after launch

On 14 April 2015 at 20:10 UTC, one day late due to an aborted launch the day before, SpaceX launched a Falcon 9 rocket with the Dragon CRS-6 resupply mission to the ISS.

(click images to enlarge)
Falcon 9, Dragon CRS-6 and 2 debris pieces, 20 minutes after launch

I watched the live webcast of the launch, and then 20 minutes later I watched the Dragon craft make a pass through Orion low in the West, before entering Earth shadow.

With a pass so low in the west in the evening, I expected it to be faint, but it actually was easily visible by the naked eye reaching mag. +1.5 (about as bright as the brightest stars in Orion, barely fainter than Betelgeuse which it passed close by [edit: but see below...]). It was some 30-45 seconds late on Jon Mikel's estimated initial orbit.

My images show up to three additional, fainter objects (I did not see them visually) close to the Dragon (see image above which shows them al three). These are the two jettisoned solar panel covers, and either the jettisoned nose-cone or the Falcon 9 upper stage (probably the latter). Unlike the Dragon, which is steady, these three objects are irregular in brightness, as they are tumbling.

[edit 15 Apr 10:15 UTaccording to Cees Bassa the bright object is actually the Falcon 9 upper stage, the fainter object just above and very close to it the Dragon CRS-6, while the two flaring faint objects upper and bottom are the solar panel covers]

The image below is a stack (combination) of five images taken slightly earlier, showing the Dragon Falcon stage and the flashing (tumbling) debris pieces crossing the top of Orion (Betelgeuse is top left):

stack of five 2.5 second images separated by 10 seconds

Two other single shots from that sequence, showing  the debris pieces flashing up alongside the Dragon Falcon:

Dragon and ISS will berth on April 16 and I hope to have some opportunity to observe them close together.

(many thanks to Jon Mikel for his orbital estimate)

Thursday, 9 April 2015

Chasing USA 186

After Greg did the last observations from the southern hemisphere mid-February, the northern hemisphere observers recovered the KH-11 CRYSTAL ('Keyhole') optical reconnaissance satellite  USA 186 (2015-042A) late March. Alberto Rango captured it on March 30 from Italy and several observers have followed since. I observed it on April 6 in early twilight. Below is one of the images, showing it passing west of Castor and Pollux in a still blue twilight sky:

The current elements are here. USA 186 is currently moving in a 269 x 467 km orbit.

Next is the hunt for USA 245, the other West (evening) plane KH-11 that should emerge out of its winter shadow blackout by now. The East plane KH's, USA 161 and USA 224 will not be recoverable until early summer.