Dark moves at Geosynchronous altitude: Mentor 6 and Luch (Olymp) 2 have repositioned

Mentor 6 on April 16, 2024. Click image to enlarge

A number of SIGINT satellites in geosynchronous orbit have been moving lately. A small roundup:

There is the brand new SIGINT satellite Mentor 10 (USA 353, 2024-067A) that is slowly drifting westwards to its operational position by ~1.35 degrees per day, since its launch and initial insertion at longitude 100 E on April 9. This was discussed in this previous blogpost. 

But an earlier Mentor (also known as ADVANCED ORION), Mentor 6 (2012-034A), has also been moving recently, from longitude 55.6 E to 51.1 E. This move happened somewhere between the second week of January and the second week of April. The image above shows it on April 16.

The Russians too have recently moved one of their SIGINT satellites again, LUCH (Olymp) 2 (2023-031A). It has now been placed near longitude 4.75 E, close to the commercial satellite ASTRA 4A. The daily distance of LUCH (Olymp) 2 to ASTRA 4A varies between 20 and 70 km. The move was initiated on March 26 and completed by April 2, 2024. The image below shows it on April 16:

 

Luch (Olymp) 2 near Astra 4A. Click image to enlarge

 

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This is the fifth relocation of Luch (Olymp) 2 since launch in May 2023 (see diagram above). Each time it is relocated, it is put close to a commercial telecom satellite (see also the second part of this earlier post). The purpose is eavesdropping on c.q. mapping of  communications and data streams, and potentially also interference.

PAN/NEMESIS-1 (2009-047A), the enigmatic US SIGINT satellite that played the same game since 2009 (see my 2016 article in The Space Review), is still slowly drifting westwards at an average (but somewhat variable) rate of ~0.03 degrees in longitude per day:

Click diagram to enlarge

A so far unidentified object in GEO near PAN and Eutelsat Hot Bird 13B [UPDATED]

PAN on March 4, 2024 (click image to enlarge)

UNID near PAN on March 8, 2024 (click image to enlarge)

In the evening of March 8 I did some observations to check upon the drifting PAN/NEMESIS-1 satellite. To my surprise, there was another object there that is not in the current catalogue (as of 10 March 2024). It wasn't there yet when I imaged the area 4 days earlier, in the evening of March 4, as can be seen by comparing the two images above.

Most likely this UNID is some commercial geosynchronous satellite that has been relocated without the 18th STS having caught that move yet. But it could also be something new. For now, it remains unidentified.

The UNID is located at about 33.8 E longitude. A very provisional elset:

UNID ML080324
1 99999U 24000X   24068.68698391 0.00000000  00000-0  00000-0 0    03
2 99999   0.0001  87.9800 0002372 229.7255 130.2564  1.00270000    07

The object could perhaps be the newly launched Chinese satellite WHG-01 (2024-040A). It was launched from Xichang a week ago, on 29 February 2024. Currently (March 11, 2024), only an 8-day old GTO elset is available for the object. That elset combined with the elset for the UNID above suggests that the satellite could have been inserted into GEO at 33.8 E on March 6 near 11 UTC.

Over the half hour arc that I imaged it on March 8, the UNID remained stationary. 

PAN/NEMESIS-1 is meanwhile slowly drifting west (the drift can be seen in the images above too, by comparing the distance of PAN/NEMESIS-1 to EUTELSAT HOT BIRD B13), as it has been doing for quite a while now. On 2024 March 8 it was near longitude 33.45 E. It is currently drifting at a rate of approximately -0.03 degrees per day.

 

PAN longitude of subsatellite point over time (click diagram to enlarge)

NOTE: an initial mix-up of the names of two recently launched Chinese GEO sats was corrected.

 

UPDATE 14 March 2024:

Space-Track, since yesterday (first non-GTO TLE has epoch 24073.71736125 = 13 March 2024 17:13 UTC), finally also places an object  in this position, catalogue nr 59069, COSPAR 2024-040A. Provisionally named "Object A", but the Cospar code indicates this would indeed be the Chinese satellite WHG-01.

Recovering USA 310, PAN and Trumpet 2

 

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Our coverage of classified objects in high altitude orbits has been waning over the past few years. In February, I made a first attempt to recover some. In the past two weeks, I again recovered a number of these objects, as a by product of testing a ZWO ASI6200MM camera (that ultimately is going to be installed on the roof of the Delft Technical University Aerospace faculty).

One of the objects I recovered, is a very unusual one: USA 310 (2020-083A). This object is in an odd 58.5 degree inclined, 11097 x 11074 km MEO orbit. It was launched on 13 November 2020 as NROL-101 (see this 2020 blogpost). We tracked it and it's Centaur upper stage for a couple of weeks, but lost it after February 2021. In other words: it had not been seen for the last 2.5 years!

That is, untill I serendipitously picked it up last August 22, while imaging geostationary satellites. In the imagery, a streak was encountered (see image above). It is a fit with USA 310. I managed to track it again during several nights the past two weeks. Frankly, I am not 100% sure whether it is USA 310 or the Centaur upper stage from that launch, but it does not seem to have the periodic brightness variation the Centaur upper stage showed in 2020/2021. And it is (relatively) bright only in the eastern part of the sky, just like USA 310 back in 2020/2021.

More objects were recovered. Several geosynchronous objects that hadn't been observed for a while, were imaged. One of them, the enigmatic PAN (2009-047A), had moved (just as it used to frequently do in the past, see my in-depth article on PAN in The Space Review from October 2016). I recovered it at longitude 39.7 degrees East, in the vicinity of Express AM-7. Observations over the past two week show it is stationkeeping, so it appears to be still operational (see also this post from 2021, when after several years of being stable at 47.7 E, it started to drift). Below is the recovery image:

click image to enlarge

Coverage of high altitude objects in HEO has likewise become spotty. I observed a number of them late February (see this blogpost), and again did so the past two weeks (a.o. TRUMPET 1 and USA 278). I recovered the SIGINT satellite TRUMPET-2 (1995-034A) on September 5, which had not been seen for almost 2 years:

 

One reason why I only sporadically track objects in GEO and HEO is that identifying and measuring them is much more labour-intensive than video-tracking objects in Low Earth Orbit, as identifying and measuring is still done manually for these objects by me. One day, I should get myself some software to make this a more easy task...

PAN is moving back westwards again

 

click diagram to enlarge

In September 2021 I wrote a blogpost noting that the enigmatic geosynchronous SIGINT satellite PAN/NEMESIS I (2009-047A) had left 47.7 E and was drifting eastwards. By 30 August 2022 it had drifted as far as 63.1 E.

But somewhere in September 2022, it reversed its drift and started to move Westwards again. Greg Roberts in South Africa recovered it on 30 September 2022 at 55.7 E after he looked for it in vain at more eastward positions.

From tracking data over the period May 2021 - August 2022, PAN was drifting eastwards at a rate of about 0.27 degrees/day. The drift started late February 2021.

It subsequently must have rapidly moved West again, by at least 0.23 degrees/day. It is not clear yet whether the drift continues, or if it is now stable at 55.7 E. Future observations will tell.

At the time of the eastward drift, I was not sure whether the drift was deliberate or the result of an operational "end-of-life". With the halt of the drift and subsequent rapid move westwards this month, it seems to me that the drift was deliberate and the satellite is still operational.

PAN/NEMESIS I was launched in 2009 and is a SIGINT satellite with a very unusual role. As the diagram in top of this post shows, it frequently relocated between late 2009 and late 2013 (which was very unusual), stalking a number of commercial communications satellites and eavesdropping on them. By 2014, this behaviour suddenly stopped, and for a long time it was kept at a stable position near 47.7 E, untill it started to drift in February 2021.

Six years ago I wrote an in-depth article on this enigmatic satellite for The Space Review that you can read here.

PAN/NEMESIS 1 is still drifting

 

click image to enlarge

In a blog post in September, I wrote that after almost eight years of being steady at longitude 47.7 E, the classified  SIGINT satellite PAN/NEMESIS 1 (2009-047A) had started to slowly drift eastwards, with the drift starting in February 2021.

Observations on the evening of November 8 show that it is still drifting. Currently it is near longitude 54.8 E, close to Yamal 402 and the grouplet GSAT 8, GSAT16 and GSAT 29, as is visible in the image above.

As it is drifting eastwards, it is getting lower in my sky: currently it is at 14.7 degrees elevation above my northeastern horizon.

The history of PAN's relocations so far (for backgrouds on PAN, its probable role and its frequent relocations during the first five years of its life, see my 2016 article in The Space Review):

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PAN (NEMESIS 1) is on the move again

Pan on August 8/9, 2021, imaged from Leiden. Click image to enlarge

Five years ago, in 2016, I wrote a long article in The Space Review titled "A NEMESIS in the sky: PAN, Mentor 4 and close encounters of the SIGINT kind". The primary subjects of that article were two SIGINT satellites: PAN (Nemesis 1) and Mentor 4.

In the article, I discussed what we had observed and deduced about PAN as amateur trackers, to what had been recently revealed about PAN by leaked documents from the Snowden files.

In the article I documented the frequent movements of PAN (2009-047A): for four years between its launch in September 2009 and mid 2013, PAN, very unusual for a geosynchronous satellite, was roving from location to location, each time being put close to a satellite for commercial satellite telephony.
For information on the "why" of that, and the larger context of it (a new kind of SIGINT information gathering), I refer to the earlier mentioned Space Review paper which goes into details.

Mid-2013, four years after launch, the frequent relocations stopped. For 8 years, the position of PAN remained stable in longitude near 47^o.7 E. It's roving days, snooping around and sniffing other satellites, were over. Until this year.  

Somewhere between 6 February and 7 May 2021, PAN started to move again, eastwards in longitude. Observed longitudes over the period May-August 2021 suggest a drift eastwards at about 0.025 deg/day. 

Assuming a stable drift, the move appears to have been initiated within a few days of 11 February, 2021.The last observation still showing PAN at 47.7 E was on 6 February 2021 (as it happens, our network did not observe it again untill early May 2021 when it had already moved eastwards by two degrees).

The diagram below (an updated version of one that appeared in my 2016 Space Review article) shows the positions in longitude that PAN has been taking up since its launch in 2006. Note the frequent relocations over the period 2009-2013, then the long stabilization at 47.7E, and the start of a new drift episode in 2021:

click diagram to enlarge

The question now is, what this drift since February means:

(1) Has it deliberately been brought into a drift state to move it to an eventual new position? 

(2) Has it reached end-of-life and been manoeuvered into a graveyard orbit?

A 'graveyard orbit' is usually an orbit that is located at least 235 km higher than a geosynchronous orbit. That does not appear to be the case here: if anything, the orbit seems to be a few km lower than it previously was. So it appears to be option (1).

It will be interesting to see whether PAN will stabilize its longitude at some point or not, and where that will be. Unfortunately, as it is drifting eastwards it is getting lower in my sky (currently, it is some 16 degrees above my local horizon), and there do not appear to be many other amateurs covering it currently.

It would be interesting to see whether radio observers can detect radio signals from PAN, which shortly after launch was emitting at frequencies similar to that of the "UFO" (UHF Follow On) constellation.

PAN on 2/3 June, 2021, imaged from Schiermonnikoog Island. Click to enlarge

LUCH (Olymp-K), an eavesdropping SIGINT snooping around commercial comsats

 

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Back in 2016, I published an article in The Space Review (A NEMESIS in the sky: PAN, Mentor 4 and Close Encounters of the SIGINT kind) about the mysterious US classified satellite PAN, and Mentor 4, another classified US satellite.

Both are SIGINT satellites launched in 2009, that are positioned close to commercial telephony communications satellites in GEO in order to eavesdrop on their communications. While Mentor 4 (an ADVANCED ORION) dedicatedly covers Thuraya 2, PAN (NEMESIS 1) moved from satellite to satellite in a 'roving' role every few months during the first 5 years of its operational existence. Its sister ship CLIO (NEMESIS 2) launched in 2014 has done pretty much the same.

But (of course) the USA is not the only country playing this game. In the same year that CLIO (NEMESIS 2) was launched, the Russian Federation launched LUCH (2014-048A), aka OLYMP-K or OLIMP-K. In 2015, in an essay in The Space Review, Brian Weeden pointed out that LUCH was roving from satellite to satellite too, possibly eavesdropping on their communications. This created headlines at the time. By all means, LUCH/OLYMP-K is the Russian equivalent of PAN and CLIO.

The diagram below shows the frequent repositionings of LUCH/OLYMP-K over the years ( a table with major repositionings is at the end of this post):

click diagram to enlarge

LUCH has recently (in the second week of February, 2021) been relocating from longitude 3 W to 8 W and is now positioned near EUTELSAT 8 WEST B (2015-039B). Before the relocation, it had been close to ABS-3A (2015-010A) for several weeks. 

I shot this image below on March 29th, when LUCH and EUTELSAT 8 WEST B were about 90 km apart:

 

click image to enlarge

The image was made with a CANON EOS 80D and Samyang 2.0/135 mm lens (10 seconds at 1000 ISO) and was a by-product of targetting MEV-2 and several classified objects in this stretch of sky.

The table below gives longitudinal positions for LUCH/OLYMP-K. The table focusses on major relocations.

Dates refer to he moments the longitude appears to get stabilized, and have generally been preceeded by a period of drift. Also indicated is what satellite was closest to LUCH/OLYMP-K at the start of each stable period. Note that in several cases, multiple satellites were close by and possibly targetted as well.

TABLE: positions of LUCH/OLYMP-K since late 2014 

DATE          LON      NEAR

17-02-2021    08.1 W   EUTELSAT 8 West B       2015-039B
06-11-2020    03.1 W   ABS-3A                  2015-010A
28-09-2020    04.9 W   Eutelsat 5W B           2019-067A
11-05-2020    01.1 W   Intelsat 10-02          2014-058A
28-03-2020    21.5 E   EUTELSAT 21B            2012-062B
28-11-2019    70.6 E   EUTELSAT 70B            2012-069A
22-10-2019    68.4 E   Intelsat 20             2012-043A
25-08-2019    65.9 E   Intelsat 17             2010-065B
01-07-2019    64.0 E   Intelsat 906            2002-041A
21-02-2019    60.0 E   Intelsat 33E            2016-053B
28-10-2018    57.0 E   NSS 12                  2009-058A
03-07-2018    49.9 E   Turksat 4B              2015-060A
07-06-2018    48.0 E   Eutelsat 28B            2008-065B
27-04-2018    47.5 E   Yahsat 1B               2012-016A
17-01-2018    41.9 E   Turksat 4A              2014-007A
25-10-2017    38.1 E   Paksat 1R               2011-042A
18-08-2017    32.7 E   Intelsat New Dawn       2011-016A
14-09-2016    09.9 E   Eutelsat 10A            2009-016A
11-01-2016    01.1 W   Intelsat 10-02          2004-022A
05-10-2015    24.3 W   Intelsat 905            2002-027A
26-06-2015    18.1 W   Intelsat 901            2001-024A
22-02-2015    96.4 E   Express AM-33           2008-003A

Testing a new lens for GEO and HEO (SamYang 2.0/135 mm)

The past week brought some clear skies. It also brougt me a new lens, a SamYang 2.0/135 mm ED UMC.

This lens had been on my wish-list for a while, as a potential replacement for the 1979-vintage Zeiss Jena Sonnar MC 2.8/180 mm I hitherto used for imaging faint Geosynchronous (GEO) and Highly Elliptical Orbit (HEO) objects, objects which are typically in the magnitude +10 to +14 range.

The 2.0/135 mm SamYang lens has gotten raving reviews on photography websites, several of these reviews noting that the optical quality of this lens is superior to that of a Canon 2.0/135L lens. And this while it retails at only half the price of an L-lens (it retails for about 460 to 500 Euro).

While I have the version with the Canon EF fitting, the SamYang lens is also available with fittings for various other camera brands.

Focussing is very smooth and easy with this lens. Unlike a Canon-L lens, the SamYang lens is fully manual (both focus and F-stop), but for astrophotography, manually focussing is mandatory anyway. The general build of the lens is solid. It is made of a combination of metal and plastic.

While not particularly lightweight, the lens is lighter in weight than my 1979-vintage Zeiss (which is all-metal and built like a tank, in true DDR fashion). The SamYang has a somewhat larger aperture (6.75 cm) than the Zeiss (6.42 cm), meaning it can image fainter objects. It also has a notably wider field of view (9 x 7 degrees, while the Zeiss has 7 x 5 degrees).

So for me, this seemed to be the ideal lens for GEO and HEO.

And after two test nights I can confirm: this SamYang lens indeed is spectacularly sharp. The first test images, made on January 15 and 16, have truely impressed me. Even at full F2.0 aperture, it is sharp from the center all the way to the edges and corners of the image.

Here is a comparison of the image center and the upper right corner of an image, at true pixel level. There is hardly any difference in sharpness:

click to enlarge

The images below, taken with the SamYang on a Canon EOS 80D, are crops of larger images, all but one at true pixel level.

The first image is a test image from January 15, a nice clear evening. It shows two objects in HEO: a Russian piece of space debris (a Breeze-M tank), and the classified American SIGINT satellite TRUMPET 1 (1994-026A). Note how sharp the trails are (this is a crop at true pixel level):

Click image to enlarge

The next night, January 16, I imaged several geostationary objects (which at my 51 degree north latitude are low in the sky, generally (well) below 30 degrees elevation). While the sky was reasonably clear, there were lingering aircraft contrails in the sky, locally producing some haze. Geostationary objects showed up well however, better than they generally did in the Zeiss images in the past.

The image below, which is a crop of a larger image, is not true pixel size, but slightly reduced in size to fit several objects in one image. It shows the Orion Nebula, several unclassified commercial GEO-sats, the Russian military comsat KOSMOS 2538 (BLAGOVEST 14L), and the classified Italian military communications satellite SICRAL 1B (2009-020A):

Click image to enlarge

The images below are all crops at true pixel level. The first one shows the US classified SIGINT satellite PAN/NEMESIS I (2009-047A), shadowing the commercial satellite telephony satellite YAHSAT 1B. It also shows a number of other unclassified commercial GEO-sats.

PAN/NEMESIS 1 is an NSA operated satellite that eavesdrops on commercial satellite telephony (see my 2016 article in The Space Review).

Note that this image - just like the next images- was taken at very low elevation, and from a light-polluted town center.

click image to enlarge

The image below shows another US classified SIGINT satellite, Mentor 4 (2009-001A), an ADVANCED ORION satellite. It shadows the commercial satellite telephony satellite THURAYA 2 (more backgrounds on this in my 2016 article in The Space Review). At magnitude +8, it is one of the brightest geosynchronous objects in the sky (note how it is much brighter than THURAYA 2):

click to enlarge

The last image below again is a classified US military SIGINT satellite, MERCURY 2 (1996-026A). While 24 years old it is, together with its even slightly older sibling MERCURY 1 (which I also imaged but is not in this image), probably still operational:

Click image to enlarge

After these two test nights, I am very enthusiastic about the SamYang lens. It is incredibly sharp, also in the corners, easy to focus, goes deep (in terms of faint objects), and overall performs excellent. I also like the wide field of view (compared to the 180 mm Zeiss which I previously used to target GEO). Together with the equally well performing SamYang 1.4/85 mm, it might be the ideal lens for imaging GEO and HEO.

Astrometric data on the targetted satellites from these test images are here and here. The astrometric solutions on the star backgrounds in the images had a standard deviation of about 2".

Added 20 Jan 2020:

This last image (reduced in resolution to fit) was taken this evening (20 January) and shows Trumpet 1 (1994-026A) passing the Pleiades:

Click image to enlarge

SIGINT Galore!

USA 136 (Trumpet 3), a TRUMPET in HEO. 28 Nov 2016
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The evening of 28 November was very clear - no moon and an extremely transparent sky, with temperatures around zero.

I used it to target several objects in GEO and HEO. Due to the favourable sky I could use exposure times twice as long as usual.

All the classified objects imaged were Signals Intelligence (SIGINT) satellites, i.e. eavesdropping satellites. The image above shows you one of the TRUMPET satellites, USA 136 (1997-068A), crossing through Andromeda. This is an object in a 63 degree inclined HEO orbit. The satellite was coming down from apogee at that moment and at an altitude of ~31 500 km.

Below is another object in HEO, USA 184 (2006-027A). This too is a SIGINT satellite, part of the TRUMPET-Follow On program (aka Advanced TRUMPET. It also serves as a SBIRS platform.

USA 184, a TRUMPET-FO in HEO, 28 Nov 2016
click to enlarge

This object was near apogee at this moment, at an altitude of 39 000 km over the Faroër Islands, which is why it looks stellar in this 20-second exposure. The star field is in Cassiopeia.

Both these objects hadn't been observed by our network for a while, hence they were somewhat off their predictions (1.5 degrees in position in the case of USA 136; and 1 degree off position in the case of USA 184).

I also briefly imaged a part of the geosynchronous belt, much lower in the sky. The targetted GEO objects were SIGINT satellites too: both Mercury 1 and Mercury 2 (1994-054A and 1996-026A), The Advanced ORION satellites Mentor 4 and Mentor 6 (2009-001A and 2012-034A) and the NEMESIS satellite PAN (2009-047A).

PAN and Mentor 4 (both shown below) have a story attached to them and were the subject of my recent article in The Space Review, which you can read here.

PAN (USA 207), a NEMESIS in GEO, 28 Nov 2016
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Mentor 4 (USA 202), an Advanced ORION in GEO, 28 Nov 2016
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A NEMESIS in the sky: PAN, Mentor 4 and close encounters of the SIGINT kind

I have published an article with the above title in The Space Review. Click here to read it.

Geostationary bonanza

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The images above and below are two small parts of one single image shot on May 2nd 2016, using a SamYang 1.4/85mm lens on a Canon EOS 60D with 30 seconds exposure (ISO 1000) under a very dark sky. These two image excerpts overlap in the corner: the upper right corner of the image excerpt above overlaps with the lower left corner of the image excerpt below.

Although both sub-images are only a few degrees wide, they show a bonanza of objects, including 3 classified objects.

In the image above, 11 objects including the classified SIGINT satellite PAN (2009-047A) are visible. PAN is parked next to the commercial communications satellite Yahsat 1B.

In the image below, 10 objects including two classified objects are visible: the two classified objects are the SIGINT satellite Mercury 1 (1994-054A), and the SIGINT satellite Mentor 4 (2009-001A), the latter parked next to the commercial communications satellite Thuraya 2.

The full 10 x 14 degree image, of which the images featured here are small excerpt parts, shows over 30 objects.

click to enlarge

Imaging a "UFO" (Ultra High Frequency Follow-On)

UFO F2 on 3 March 2016
(click image to enlarge)

The image above is my first image of a UFO...

(* cue X-Files tune *)

No need to call in Mulder, however. The object in the image is a geosynchronous satellite, UFO F2 (1993-056A).

The truth is out there

The acronym 'UFO' in this case does not stand for the classic Unidentified Flying Object. It stands for Ultra High Frequency (UHF) Follow-On, the name of a class of US Navy communication satellites.

The UFO satellite constellation consists of 11 satellites (not all of them operational) in geosynchronous orbit, launched between 1993 and 2003. It serves fleet-wide communication needs for the US Navy (including its submarines, but also Marine units on land). The system is currently being replaced by the newer MUOS constellation (see a previous post) and will gradually be phased out.

UFO satellite constellation on 9 March 2016
(click image to enlarge)

The first launch in the series, the launch of UFO F1 on 25 March 1993 with an Atlas 1 from Cape Canaveral, resulted in a partial failure to reach the intended geosynchronous orbit due to the failure of one of the rocket engines. The second UFO launch, UFO F2, the one imaged above, was the first truely successful launch of this satellite class.

USA 236 on 28 February 2016
(click image to enlarge)

I imaged more geosynchronous objects the past week, taking advantage of clear moonless evenings. The image above shows a star field in Orion in the evening of 28 February 2016, with USA 236 (SDS 3 F7, 2012-033A), an SDS data communications satellite in geosynchronous orbit. These satellites relay data from other US military satellites, optical and radar reconnaissance satellites in Low Earth Orbits such as the KH-11 'Keyhole'/CRYSTAL, Lacrosse (ONYX) and FIA (TOPAZ), to the US.

PAN on 28 February 2016
(click image to enlarge)

I also did my periodic revisit of the enigmatic SIGINT satellite PAN (2009-047A) as well (see image above). PAN is still stable at 47.7 E (see my long-term analysis here), near Yahsat 1B. The image above shows it near that satellite and a number of other commercial communications satellites in an image taken on 28 February 2016.

Mercury 1 r on 3 March 2016
(click image to enlarge)

On Feb 28 and March 3, I recovered Mercury 1 r (1994-054B), the upper stage from the launch of the Mercury 1 SIGINT satellite. We had lost this object for a while, it had not been seen for 153 days when I recovered it. The image above shows it in Hydra on 3 March 2016.

USA 186 on 5 March 2016
(click image to enlarge)

As spring is approaching, the visibility of satellites in Low Earth Orbit is gradually coming back for northern hemisphere observers.  This means we can take over from our lone southern hemisphere observer, Greg. The image above shows the KH-11 'Keyhole'/CRYSTAL optical reconnaissance satellite USA 186 (2005-042A) imaged on 5 March 2016.

Imaging Geostationary satellites, and PAN's past relocations

Last week saw some clear evenings, and I used one of them to image some geostationary satellites. It concerned "the usual suspects": MENTOR's, MERCURY's and the enigmatic, probably SIGINT satellite PAN (2009-047A). The latter satellite has not been moved for quite a while now: since the end of 2013 it is at longitude 47.7 E, parked close to a number of commercial comsats. In the past it was frequently relocated, taking positions next to various commercial COMSATS. In four years time between 2009-2013, it moved at least 9 times (which is a lot) to various longitudes between 33 E and 52.5 E.

PAN amidst several commercial COMSATS on 9 December 2015 (click to enlarge)

The diagram below charts these frequent movements of PAN. Relocations typically took place about once every 6 months. Late 2013, they stopped. PAN however must still be operational, as active station-keeping is necessary for it to stay at 47.7 E.

relocations of PAN over time, 2009-2015 (click to enlarge)

Four other SIGINT satellites and a military comsat were imaged as well: Mentor 4 (2009-001A) and Mentor 6 (2012-034A), Mercury 1 (1994-054A) and Mercury 2 (1996-026A), and the military comsat Milstar 5 (2002-001A).

Mentor 4, next to commercial comsat Thuraya 2 on 9 Dec 2015 (click to enlarge)

Mentor 6 and a number of commercial satellites, close to the Orion nebula, on 9 Dec 2015

Using the remote telescope at Warrumbungle (MPC Q65) in Australia, I recently (4 December 2015) also checked-up on the recently launched US Navy COMSAT MUOS 4 (2015-044A). It is still at its check-out location over the Pacific at longitude 172 W, but some recent press statements suggest check-out has been successfully completed, and it will be moved to its operational position at longitude 75 E near India in the spring of 2016.

CLIO

On 16 September 2014, the US military launched an enigmatic satellite (2014-055A) from Cape Canaveral into a geostationary orbit. It was not disclosed for which agency the object was launched (this is information that usually is disclosed). Nor what its function would be (this is information sometimes but not always disclosed). All we know is the rather uninformative name, CLIO, that it was built by Lockheed Martin and based on their commercial A-2100 bus.

CLIO imaged on May 13, 2015 (click image to enlarge)

CLIO is currently located at longitude 108.0 E, over Indonesia, where I imaged it yesterday using the 0.51-m telescope of Warrumbungle (MPC Q65) in Australia. The image can be seen above: CLIO is positioned just north of Telkom 1 (1999 042A), an Indonesian satellite for satellite telephony. (since Telkom 1 is also built on a Lockheed A2100 bus, the brightness difference in the image above is interesting, and probably due to different attitudes (orientations) of the satellites, although it potentially could also indicate custom components on CLIO, e.g. something like a large dish antenna).

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In many ways CLIO appears similar to another enigmatic satellite,  PAN (USA 207, 2009-047A), launched in September 2009 and infamous among our amateur tracking network for its frequent repositioning.

PAN was also built by Lockheed Martin and like CLIO based on the A-2100 bus. As with CLIO, the government agency behind it was not disclosed, and no indications of its role provided. What was known, is that PAN was developed and built rapidly (in less than 3 years time) using off-the-shelf commercial parts, apparently in response to an urgent need of some undisclosed government agency (which I suspect is either the CIA or NSA). Much speculation has occurred about the role of the spacecraft. The frequent relocations (which stopped at the end of 2013) make clear it is not a simple communications or early warning platform. PAN is currently located at longitude 47.9 E over east Africa.

Because of the similarities, several analysts believe that CLIO, five years after PAN, is a follow-on to the PAN program. The two satellites are currently 60 degrees separated in longitude.