Sunday, February 07, 2016

Inconsistent DPRK versus JSPoC orbit claims for Kwangmyŏngsŏng 4

This post is a brief update to my more elaborate post of earlier today here.

As I wrote in that post, western military tracking of the N-Korean satellite places it in an orbit with perigee at 465 km, apogee at 502 km and an orbital inclination of 97.5 degree.

It is interesting to compare this with the (English) radio announcement of the DPRK itself, which you can hear here.

In that bulletin, the orbit is given as having perigee at "494.6 km", apogee at "500 km", and an orbital inclination of "97.4" degrees.

Compare this to JSpOc data: 465 km, 502 km, 97.5 degrees.

The DPRK apogee perigee altitude does not match the JSpoC data, which gives a clearly lower apogee perigee at 465 km. This could in theory be due to initial errors in the JSpOC tracking data (the first few orbit determinations are always less accurate). But the magnitude of the difference is such, that I doubt that.

Assuming that the numbers in the DPRK radio bulletin are not based on actual North-Korean tracking data, but instead based on a pre-launch desired orbit, then maybe this could indicate that the satellite did end up in a slightly lower orbit than intended.

Well see if the difference keeps standing with more western tracking data added...

[update: Jonathan McDowell suggested that perhaps the Koreans used another spheroid (earth shape) to refer to. I doubt that: not only would I expect similar discrepancies in the apogee altitude as well in this case (the apogee altitudes given by JSpOC and N-Korea are close), but moreover, 30 km is a large difference. I know of no ellipsoid that differs by as much as 30 km from the WGS84 ellipsoid]

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North Korea has launched Kwangmyŏngsŏng 4

Launch of KMS-4 (still from N-Korean tv announcement)

My previous blogpost of Feb 4 (with an update on Feb 5) discussed the announced launch of a new North Korean satellite, Kwangmyŏngsŏng-4 (KMS-4), from Sohae satellite Launch center in the northwest of North Korea.

Yesterday (Feb 6), North Korea suddenly shifted the start of the launch window one day forward, from February 8 to February 7 (local date). No reason was given for this date shift.

The actual launch happened this morning at 00:29 UT (February 7, 2016), according to USSTRATCOM.

It appears to have been successful, to the extend that  they did successfully put an object into orbit, as the US military tracking network confirms. As the history with KMS 3-2 shows, whether the payload is really operational is another question and as for yet unanswered.

North Korean television announced the successful launch a few hours ago, in a bulletin in characteristic fashion, including images of the launch and of Kim Jong-Un watching the launch from Sohae:






Launch time

The launch time prediction of my previous post (and in this seesat list post) turns out to have been correct.

I indicated a launch between 00:24 and 00:41 UT (a 17 minute period out of a 5 hour window indicated by the North Koreans). The start of this window at 00:24 UT was based on the assumption of a launch at a similar solar elevation at Pyongyang as during the 2012 launch of KMS 3-2 (the end at 00:41 UT was based assuming a launch exactly 5 hours after Pyongyang sunrise rather than at a similar solar elevation to 2012).

The actual launch occurred at 00:29 UT, only a few minutes from the start of the window which I indicated. It corresponds to a solar elevation of 18.0 degrees at Pyongyang (the 2012 launch happened at a solar elevation of 17.5 degrees).


Orbit

The first orbital elements from JSpOC show two objects in orbit as a result of the launch: an A-object (catalogue number 41332, 2016-009A) and a B-object (catalogue number 41333, 2016-009B). The A-object is likely the satellite.



The A-object moves in  a 97.5 degree inclined, 465 x 502 km sun-synchronous polar orbit with an orbital period of 94.3 minutes. The satellite makes daily morning passes around ~9h am. It has a repeating ground-track every 4th day. This is consistent with a remote-sensing role.

The orbit is somewhat lower and  more circular than that of North Korea's previous satellite, KMS 3-2, which was initially placed in a 495 x 588 km orbit. Like the 2012 launch, North Korea had to perform a dogleg manoeuvre to attain an orbital inclination of 97.5 degrees after launching due south from Sohae (see discussion in my previous post).

The second, B object is the spent upper stage of the rocket, and is moving in a 433 x 502 km orbit.

The map below shows the satellite's ground-track during the first 5 orbits after launch:


North Korea's ruler Kim Jong-Un watched the launch from the grounds of the Sohae Satellite Launch Center. In the image below, he is observing the rocket ascend from a viewing platform which appears to be in front of the oval building that was erected at Sohae between March and July 2014 (see this satellite photo analysis on the 38 North blog).


A few more stills of the launch, taken from the North Korean tv broadcast:








The launch of Kwangmyŏngsŏng 4 is the second time that the North Korean rocket program was successful in placing an object in orbit. North Korea itself claims a number more successful launches, but these failed according to western sources as no objects were tracked in orbit.

Current spatial separation of the orbital planes of KMS 3-2 and KMS 4

Note added 18:00 UT, 7 Feb: a brief update noting inconsistencies between early western tracking data and a DPRK announcement is here.

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Thursday, February 04, 2016

[UPDATED] North Korea's upcoming satellite launch

North Korea's previous satellite, Kwangmyŏngsŏng 3-2, imaged in 2015
(click image to enlarge)

On February 8th, 2016, it will be the 70th anniversary of the formation of the Provisional People's Committee for North Korea by Kim Il-Sung, effectively marking the birth of the nation. And 16 February 2016 will be the 74th (actually 75th) birthday of the late Kim Jong-Il, while in addition February 14th is a day that commemorates Kim Jong-Il assuming the role of "Grand General of the DPRK". Such dates often see some significant national posturing of North Korea.

Following a nuclear test on January 6th (claimed to be a small H-bomb by the North Koreans, although western observers doubt this), North Korea has announced the launch of a satellite, with issued Broadcast Warnings pointing to a launch between February 8 and 25. The launch period starts at the date of the 70th anniversary of the Provisional People's Committee.  

Satellite image analysts at the 38 North website had already been documenting preparations for a launch at the launch site in Sohae in January. Over the past 3 year, North Korea had been making several improvements to its launch installations, building various new structures on the site.

Meanwhile, the upcoming launch has western nations and neighbouring states concerned. Especially Japan has expressed very strong concerns about the launch. Like they did in 2012, they have threathened to shoot the rocket down if it seems to be headed for Japan. That is unlikely to happen though.

The Broadcast Navigational Warnings issued delineate three splash-down areas of rocket debris:

HYDROPAC 294/16
WESTERN NORTH PACIFIC.
YELLOW SEA.
EAST CHINA SEA.
PHILIPPINE SEA.
ROCKETS.
DNC 23.
1. HAZARDOUS OPERATIONS 2230Z TO 0330Z COMMENCING
   DAILY 07 THRU 24 FEB IN AREAS:
   A. BETWEEN 35-19N 36-04N AND 124-30E 124-54E.
   B. BOUND BY
      33-16N 124-11E, 32-22N 124-11E,
      32-21N 125-08E, 33-16N 125-09E.
   C. BOUND BY
      19-44N 123-53E, 17-01N 123-52E,
      17-00N 124-48E, 19-43N 124-51E.
2. CANCEL THIS MSG 250430Z FEB 16
.

[added note: the original letter of North Korea to the Int. Maritime Organization on which this navigational warning is based, is here].

Area A is the splash-down area for the first stage, area B for the fairings, and area C for the second stage (the third stage will remain on-orbit after launch). Plotting these on a map (red boxes in map below) reveals them to be on a north-south line with azimuth ~180 degrees (yellow line), avoiding the main islands of Japan:

(click map to enlarge)

The ~180 degree launch azimuth points to a satellite launch into Polar orbit, very similar to the launch direction of North Korea's previous satellite, Kwangmyŏngsŏng (KMS) 3-2 (2012-072A) three years ago (a nice background piece on that launch by Brian Weeden discussing "satellite launch or missile test?" can be found here). Compare my map above to the map constructed from the NOTAM's for the KMS 3-2 launch in 2012 on Bob Christy's website, [edit: and see also the comparison of 2012 to 2016 in this blogpost by Melissa Hanham on the Arms Control Wonk blog].

As was the case with their previous KMS 3-2 launch, the intended satellite orbit is, given the launch direction, likely a sun-synchronous orbit with an orbital inclination of 97 degrees. The launch direction due south rather than directly into a ~97 degree inclined orbit has been chosen to avoid overflying (and debris landing on) the territories of China and Taiwan during the ascend phase. In order to reach a true sun-synchronous orbit with inclination ~97 degrees, it necessitates a dog-leg manoeuvre of the third stage with payload during the final phase of the ascend to orbit (blue line in map above, approximate only). Orbit insertion of the payload will be about ten minutes after launch, just before reaching the Phillipines.

Assuming the resulting orbit of the satellite will be similar to that of KMS 3-2 in 2012 (perigee ~495 km, apogee ~588 km, inclination 97.4 degrees), the trajectory of its first revolution around earth will look something like this (yellow dot shows satellite position one hour after orbit insertion):


(click map to enlarge)

The launch window is 17 days long, and runs daily from 22:30 to 03:30 UT, according to the Broadcast Warning. The daily 22:30-03:30 UT window is similar to that of the KMS 3-2 launch in 2012. It runs from local daybreak to just short of local noon, indicating a desire for an orbital plane resulting in morning passes.

[edit: the paragraph below was slightly editted on 5 Feb 2016, expanding the discussion of possible launch times]

In 2012, KMS 3-2 was launched at 00:49:49 UT, almost exactly two hours after Pyongyang sunrise (22:50 UT). This suggests (if a similar orbital plane with overfly times at ~9h am local time is aimed for) that the current launch might happen somewhere between 00:24-00:41 UT, depending on whether the aim is for launch at a similar solar elevation (then it will be close to 00:24 UT) or merely two hours after Pyongyang sunrise (then it will be close to 00:41 UT). However (see the next paragraph), the timing of the 2012 launch also seems to have been (at least partially) dictated by a suitable window lacking overflights by western reconnaissance satellites. As for the date, I hesitate to prophecy on this, but I wouldn't be surprised if they go - weather permitting- for February 8, the first day in the 17-day window.

It appears that the North Koreans carefully chose their launch moment in 2012. US military sources already had claimed shortly after the launch that North Korea had played a ruse on them and evidently knew when western optical imaging satellites had (and had not had) view of the launch installations. This seems to be confirmed by my independent analysis of that launch from December 2012, which showed that the North Koreans used the very end of a longer-than-usual one-hour gap in IMINT coverage of the launch site to launch. And as I wrote in that blog post, a North Korean IP address had been looking for orbital elements of  US optical and radar satellites on this very blog just days before the launch.

The ruse was apparently designed to keep the USA, Japan and South Korea in the dark about the launch moment until the actual moment of launch itself (which would be registered by SBIRS and DSP satellites), as a counter-measure to give potential intercepts of the rocket as little advance preparation time as possible.

It would be difficult for North Korea to repeat such a ruse these days, as the number of western optical and radar reconnaissance satellites has grown ubiquitously in the past three years. Assuming launch near 00:40 UT (two hours after sunrise), the most promising dates (from the perspective of relative lack of western IMINT coverage) are three dates in the first week of the launch window:  February 8, 10 and 14. But maybe North Korea is confident enough this time, following the experience with KMS 3-2, to not bother with western IMINT coverage at all.

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Tuesday, February 02, 2016

Back to basics: AEHF 2 and SBIRS GEO 2 imaged

click to enlarge

Time to go back to basics. The photo above is part of an image I shot in the evening of January 20-21, 2016. It shows a number of commercial geosynchronous satellites and two classified satellites: AEHF 2 and SBIRS-GEO 2.

This image was shot from Leiden center using a Canon EOS 60D and a Zeiss Sonnar 2.8/180 mm lens and 15 seconds exposure (ISO 1000). It shows an approximately 2.5 degree wide field in Hydra, just east of alpha Hydra. The sky was extremely transparent, and to my surprise a waxing moon in the sky was no real hindrance: conditions I do not encounter often!

Most prominent on the image (a crop out of a larger image) is the commercial Astra 1 group, a group of four satellites well known to European owners of satellite tv dishes. Just north of the group is AMOS 5, an Israeli commercial communications satellite. It suffered a malfunction on 21 November 2015, as a result of which all contact was lost.

Also visible in the image are the commercial satellite Arabsat 5C and the Chinese satellite Tianlian 1-03. The latter satellite is a Tracking- and Data Relay satellite that plays a similar role to the US TDRS satellites. The Tianlian satellites are specifically meant to relay data to and from Chinese crewed Shenzou spacecraft.

Two classified US satellites are visible in the image.

On the right is AEHF 2 (2012-019A), the second Advanced Extremely High Frequency military communications satellite. The AEHF system is a replacement for the older Milstar system, and use of this US system is shared by the military of a number of  countries, at this moment the UK, Canada, and my own country, the Netherlands. It is eventually to consist of 6 satellites, of which 3 have been launched as of early 2016. The satellites have been designed to be resilient to jamming and intercept efforts.

On the left is SBIRS GEO 2 (2013-011A), the second geostationary satellite in the Space Based Infra Red System, a series of US infra-red Early Warning satellites meant to detect missile launches. I discussed this system in detail in several recent blogposts, as this system might have played a role in potentially detecting the missile that shot down Malaysian Airlines flight MH17. Indeed, the satellite imaged here, SBIRS GEO 2, is one of the SBIRS satellites that had sight on the Ukraine at that time.

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Saturday, January 30, 2016

MH17: On the Resurs-P1 image with "BUK's near Zaroshchens’ke" (updated)

(Note added 31 Jan 2016: Max van der Werff brought to my attention that he is "kremlintroll" and that the pdf report on the blog was not written by him, but by someone else. That was not clear to me. I have added some comments in the text below to reflect this)


Since my contribution to the January 22 Dutch Parliamen hearing on flight MH17, a number of people have reached out to me with satellite-related questions about MH17.

One of them was Dutch blogger Max van der Werff, who in a tweet from 28 Jan 2016 asked me if I had anything to say about this analysis (pdf) by a blogger named "Kremlintroll" [edit: this turns out to be Max himself: but the pdf analysis on his blog was by someone else]. It concerns a report with purported Russian satellite imagery of what was claimed to be BUK installations in a field near Zaroshchens'ke, on the Ukranian side of the front. It in addition includes claims that a particular US spy satellite overflew the area at the time the missile was fired.



I will answer Max' question here, but note that I do so without necessarily condoning Max viewpoints on MH17. There are a lot of bloggers expressing their (often very partisan) views on the case, and I prefer not to take sides with any of them at this moment.

At the same time, when satellite observations are brought up, I would like to see to it that the information presented is correct. So I will provide some of that information below, as it pertains to this case.

My initial intent was to keep it focussed at information about satellite passes. This is factual, objective information. While checking pass data for Resurs-P1 I did however note something that appears off with regard to one of the images. I will discuss that as well, with some reluctance: but given that I mentioned my doubts on twitter, it is fair that I should present the reasons for my doubts.

The imagery comes from a Russian government website and was earlier the target of a "photo forensics" analysis by the Bellingcat collective. The latter analysis has drawn fire from professional photo-forensic analysts, who say the analysis was flawed. This critique comes from knowledgeable people on this matter, so should be taken seriously imho.

click image to enlarge

The image (reproduced above) purports to show Ukranian BUK installations in a field near Zaroshchens'ke in Ukraine, 47 deg 59' 00" N, 38 deg 27' 05" E. Text on the image states it was taken on 17 July 2014 at 11:32 (no timezone given, but presumably standard Moscow Time, UTC +3).

The pdf in the blog by "Kremlintroll" discusses the image as part of a larger narrative. In addition (and this was my initial focus), the author of the pdf claims that a US spy satellite actually overflew the MH17 disaster area at the time the missile was fired:

"According to our data from 17:06 till 17:21 Moscow time on July 17 over the South-Eastern territory of Ukraine flew a US space satellite. This is a special device of the experimental space system designed to detect and track various missiles launches"
[edit: the quote above is purportedly from a Russian officer, Lt-Gen Makushev]

US spy satellite fly-over?

Let us examine the latter claim first, as this is squarely within my field of expertise. As we will see, the claim appears to be false.

The description seems to refer to one of the Space Tracking and Surveillance System (STSS) demo satellites in Low Earth Orbit (note the given pass time of 15 minutes in the quote above, indicating a satellite in Low Earth Orbit). They are experimental satellites for tracking missiles, serving a role initially projected for the (cancelled) SBIRS LOW segment.  A pass of one of these satellites indeed takes about 15 minutes.

These particular satellites are tracked by our network. I checked their positions for 17 July 2014, 13:20 UT (the time of the MH17 disaster). They did not have sight of the Ukraine at that moment.

STSS demo 1 and STSS demo 2 (2009-052 A and 2009-052B) move as a pair at a fixed distance of each other: STSS demo 1 passes a given location 10 minutes after STSS demo 2 does, along a similar track.

STSS demo 2 passed over the MH17 crash area around 12:35 UT, and STSS demo 1 did so around 12:45 UT. This is more than half an hour before the MH17 disaster took place. STSS demo 1 lost view of the area around 12:55 UT, still 25 minutes before the disaster. At 13:20 UT, the time of the disaster, the satellites were south of Australia, well away from the Ukraine (map below).

click image to enlarge

STSS-ATRR, a third satellite connected to this program, was just east of Sakhalin at that time, so nowhere near the Ukraine either.

Another US spy satellite, USA 161, did pass over the area near 13:20 UT (see my previous post here). This is however a KH-11 optical reconnaissance satellite, not one designed to track missiles as claimed in the pdf analysis hosted by Kremlintroll. It also did not pass over the south-eastern territory of the Ukraine, but well west of the area in question. See my earlier post for a discussion of what this satellite might, or more likely given amongst others that the area of interest was very periferal in the footprint, might not have imaged.

In other words: the claim about a US missile-tracking satellite in Low Earth Orbit overflying the Ukraine at 17:06-17:21 Moscow daylight saving time (13:06-13:21 UT), is factually incorrect.

Of course, we should realise that three SBIRS satellites for missile detection in higher orbits (HEO and GEO) with (semi-) permanent view of the area did cover the relevant area, as I reported to Dutch Parliament, and in that sense this discussion is slightly academic: early warning satellites for missile launches did potentially observe the Ukraine at that time. This SBIRS high component in HEO and GEO however clearly is not the low orbit (fly-over time listed as 15 minutes) experimental missile tracking satellite system the Russian officer was referring to. So, this specific information is incorrect.


The photograph

So what about the satellite photograph distributed by the Russian government, showing purported BUK systems just south of Zaroshchens'ke and discussed in the pdf hosted by Kremlintroll as evidence for Ukrainian BUK deployment in the area.

I was, and am, reluctant to discuss this photograph.

First, I am knowledgeable about satellite orbits, satellite positions and satellite system specifics (the kind of factual information I provided to the Parliament committee during the hearing of Jan 22): but I am not a photo interpreter.

I want to emphasize this. Analysis of this kind of imagery preferably should be done by a professional photo interpreter.

Second, following my role in the Parliament hearing, I prefer to refrain as much as possible from making any statements that might be misconstrued as 'taking sides'.

Nevertheless, while looking at satellite pass information I noted something about this photograph, that I think is relevant. With some reluctance, I provide these observations here in this blogpost. I want to make clear that this only concerns this particular photograph: I am not saying anything about other evidence presented by various parties, and importantly: I have no desire to analyse more images. Again: that should better be done by professional photo interpreters. In a way, given the way this quickly developed on twitter, I regret mentioning my doubts about the satellite image in public, even though (as discussed below) I stand behind these doubts. Given that I mentioned my doubts on twitter, it is fair that I should present the reasons for my doubts below.


1. the satellite

First, the satellite that took the image. The image lists a time, 11:32 on 17 July 2014. Resurs-P1 (2013-030A), a Russian imaging satellite with 1-meter resolution, passed the area shown in the photograph at 08:32 UT (11:32 Moscow Standard Time, or 12:32 Moscow Daylight Saving Time) - an identification earlier also made on a Russian webforum. Other high-resolution Russian imaging satellites do not match the pass time listed. The assumption that the image was made by Resurs-P1 therefore appears a valid one and will be the starting point of the discussion below.

click image to enlarge

Resurs-P1 culminated at 57.5 degrees elevation at 08:32:46 UT (July 17th 2014 - that is 11:32:46 Standard Moscow Time, 12:32:46 Moscow Daylight Saving Time) as seen from the field imaged in the photograph (which is at 47 deg 59' 00" N, 38 deg 27' 05" E). The satellite subpoint was some 281 km west of the location shown on the photograph at the moment of culmination. The location on the photograph is within the satellites known image swath width of ~950 km (~475 km to each side of the satellite nadir).

It is therefore possible that Resurs-P1 did take an image of this field at the listed time.

That does however not necessarily mean that the image is genuine. Something isn't sitting well with me regarding this image, raising my suspicion. I will discuss this below.


2. the photograph: suspicions

(again, I want to emphasize that I am not a professional photo interpreter. Keep that in mind)

So far, what I have written above is all straightforward factual: where were what satellites at a specified moment? What I am going to write below has a larger factor of interpretation.

As mentioned, Resurs-P1 culminated at a maximum altitude of 57.5 degrees for the location in question (that is a factual observation).

This immediately made me uneasy about the featured satellite photograph. For this image seemed to be a head-on image, taken with an angle to the horizon of near 90 degrees (straight down), rather than under an oblique 57.5 degree angle.

The image should, with a culmination altitude of 57.5 degrees for the satellite, instead show the installations obliquely (i.e. skewed, i.e., not just show the tops but also show parts of lateral sides of the purported BUK installations). It should also show the landscape somewhat obliquely.

Resurs-P1 passed west of the area in question. This is towards the left side of the image. The image should therefore show the BUK installations somewhat skewed with something of the lateral sides visible on the left hand side.

I used sketchup to make a simple block-model with the dimensions of a BUK (roughly 9.9 x 3.3 x 3.8 meter), and then rendered it under a 57.5 degree angle with the horizontal. The image below shows the result as an inset in the original image.



To me, it appears that the photograph indeed should show more of the lateral sides of the purported BUK installations than it does: the installations shown in the image appear to be seen too-much head-on compared to the modelled view under a 57.5 degree angle.

There is also something off in the positions of the shadows. They should be slightly displaced to the left, compared to what the image appears to show (the sun was at azimuth 150.7 degrees, i.e. southeast, and elevation 60.6 degrees at 8:32:46 UT. The shadows should point slightly to the left in the image, even more so if the image is taken from a point to the west of the area under a 57.5 degree or smaller angle).

Taken together, it suggests that the photograph does not show a scene compliant with the geometric situation at 8:32 UT on 17 July 2014 as seen from Resurs-P1.

As a caveat, I should emphasize that we are talking about structure at the edge of the satellite's image resolution here, with objects only a few pixels wide (and again: I warn that I am not a professional photo interpreter). There might also have been done some unknown image processing, including resampling, as part of preparing the photo for publication. Still, I feel there is reason to be very cautious about these images.


A few last words on my position in this

I want to note that this is the first and last time I will, with regard to MH17, foray into the domain of satellite photo interpretation, also given the very strong reactions this has already spawned on media like twitter. Agitprops from all sides have jumped on it.

I prefer to keep my further involvement with MH17 focussed on providing factual data on satellite positions and satellite system specifications, in line with the role I played in this month's Parliament hearing. That is a position only people with an agenda could take issue with.

With all the things that have come up over the past 1.5 year, and with multiple parties involved clearly unwilling to provide pertinent data, I have taken a step back, opinion-wise. In the current situation, my aim is to not point fingers until verifiable evidence is put on the table. The report of the Dutch Safety Board is a first step into that direction, but there are still many aspects of the case that are very unclear. Clarifying these was the main point of the Parliament hearing of January 22.

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Tuesday, January 26, 2016

The Parliament Hearing

Last Friday was the MH17 hearing of the committee for Foreign Affairs of Dutch Parliament in the Dutch Parliament building in the Hague. I had been  invited as an external expert to this hearing (see a previous post), with the task to brief the parliament members on what military satellite systems from what countries might have observed the disaster, and could potentially provide useful information with a view on the criminal prosecution of the case.

An audio record of the block of the hearing that featured my presence can be downloaded here (it is in Dutch of course). Related to this, I also appeared on national television that evening (video here and below) in a long item in EénVandaag, a news background program broadcast nationwide at 6 pm. After the hearing, I also did a 20-minute live interview on national radio (audio here, below the video on that page).

It was quite an experience to be in this role, a role which I never had expected to have to play when I wrote my first blogpost on this all. I spent the better part of January doing research into even the most remotely possible questions I could imagine, digging up information, checking and re-checking facts, and writing the position paper.

The full hearing itself took 8 hours (I myself only attended some two hour of these though), and the block that included me took one hour (from 12:00 to 13:00 CET). I shared this block with Paul Riemens, who is the head of Dutch air traffic control; and prof. Piet van Genderen, who is a radar expert from Delft University.

Letter by the Minister

In the evening before the hearing, the Minister of Justice and Security, Van der Steur, had suddenly dispatched a letter to Parliament in answer to questions by Omtzigt , in which he stated that the prosecutor did receive radar and satellite data, and that in their perception there was "no need" for additional requests of those. He also mentioned that the prosecutor had insight in these data "through the MIVD"  (the Dutch Military Intelligence and Security Service) by means of "ambtsberichten" (i.e. brief statements on what the data show, not the data itself). The latter suggested to me, that the data are not declassified, and perhaps will not be declassified. Which is odd and unnecessary, as well as unwise, as I will discuss later in this blogpost.

The timing (combined with the fact that similar earlier questions by MP's Omtzigt and Sjoerdsma got unanswered) suggests that the Minister's letter to Parliament was a direct response to the position papers by Van Genderen and me, so it does seem our input into this discussion had some immediate effect.

Parliament members present

Parliament members attending the block of the hearing which I participated in, were Michiel Servaes (Labour party); Harry van Bommel (Socialist Party); Pieter Omtzigt (Christian Democrats); Louis Bontes (list Bontes/Van Klaveren, a right-wing splinter party split off from Wilders' Party for Freedom); Raymond de Roon (Party for Freedom); Sjoerd Sjoerdsma (Democrats '66); and Han ten Broeke (Party for Freedom and Liberty). Chairman of the hearing was MP Fred Teeven (Party for Freedom and Liberty: who incidentally was State Secretary at the Justice and Security department at the time of the MH17 tragedy), who is vice-chairman of the parliament committee in question.

some of the Parliament members during the hearing:
 f.l.t.r. Ten Broeke, Servaes, van Bommel and Omtzigt

Hearing proceedings and questions

Riemens, Van Genderen and me all three got a few minutes to present our information to the MP's. My main message to the committee was that there are a lot of military systems, from several countries including more than one ally of our country, that might provide useful information. I briefly outlined what kind of systems might provide what information, mentioning SBIRS, but also SIGINT and IMINT.

Next, the parliament members in the committee asked us further questions and clarifications. Servaes asked me which indications I had whether the Dutch prosecutor really needed more satellite data (harking back to the suggestions in the Minister's letter of the previous evening). Related to that, Van Bommel asked me whether my plea for an attempt to get these data and get them declassified was in the interest of transparency, or had some other additional goal. He also asked whether these data might help to further restrict the location from where the missile was fired or not. Ten Broeke asked me (and Van Genderen) for my opinion on the current government position in this.

answering questions

I amongst others answered that I was not a lawyer or attorney, but that it seemed to me that declassifying the evidence was crucial in order to be able to use them for a criminal prosecution, as well as indeed in the general interest of transparency and accountability. There are so many questions around this subject, and so many (conspiracy-) theories and different views (not to speak of desinformation floating around), that the final conclusions should be verifiable to all (after the hearing, I pointed out in the radio interview that it is also very important to the families of the victims to be able to judge these results, something also pointed out in the tv item by a father who lost his son in the tragedy).

In this context I also pointed to remarks made a year ago (17 Dec 2014) by Victoria Nuland, assistant secretary of  European and Eurasian affairs in the US government, and read these out loud to the Parliament members. During a Q & A session at the American Enterprise Institute, Nuland answered questions by a Russian reporter and said that the US government had already shared data with the Netherlands, but moreover that she expected that there:
"..will be, I believe, in the context of the Dutch case, when they roll it out – they are likely to ask us to declassify some of that, and I think we will be able to help in that regard"
In other words: she not only expects a request for declassification from the Dutch government: but she also expects that the US Government will answer positively to that request!

During the hearing, and partly in response to some of the questions,  I warned the parliament members that if these satellite data would not be pursued and a request to declassify them not be made, this could possibly stimulate a lingering feeling that the Dutch prosecution left data unchecked or unreveiled. I told them that if things transpired this way (the wording of the letter by the Minister was not so encouraging in this respect) I feared that this would potentially provide handles to those parties with an interest in denying the conclusions of the investigation, to question these results.

Omtzigt asked me if there were earlier precedents of these kinds of data being declassified. There are: in the hearing I provided the examples of infrared data on meteoric fireballs (which these satellites also register) being released to astronomers for analysis; the declassification of satellite imagery in order to argue the necessity of the invasion of Iraq at the start of the second Gulf War; and China providing satellite imagery of potential floating debris in the case of the search for the missing MH370 aircraft.

Sjoerdsma asked me whether, in case the data would be declassified and supplied, our country had the expertise to independently analyse them and verify the claims made from them. For the infrared data I answered that I am not sure, so could answer neither positively nor negatively. For IMINT and SIGINT, our country certainly has that expertise, both within our own military as well as on Dutch universities.

De Roon wanted me to clarify further which countries had what satellite systems. Bontes asked me whether the fact that we were now so reliant on foreign data from foreign systems, might be an argument to start to build, as a country, surveillance satellite capacity ourselves (I think I am really not the person to answer that question).

During my answering all these questions, van Bommel additionally asked me in what phase of the criminal investigation these data should be made public, and whether it was perhaps too early for that in the current phase.

To the latter I can agree, although (again) I am no lawyer or attorney. But I can understand that perhaps, in this phase of the inquiry, the prosecutors do not want to publicly show their hand of cards.

I do have some concern though, about whether at the end of the trajectory these data are going to be made public, in the interest of verifiability. In my opinion, they should. I find the wording of the letter by the Minister of 21 January 2016 however not very promising in that respect.

The  contributions by the other invited experts contained some significant points. Van Genderen for example made very clear that having the secondary radar data is not enough. He also made very clear that Ukrainian claims that all their radar systems were down for maintenance that day, are hard to believe, as that is against what is normal. Riemens made clear that normally, the air traffic controller on duty will be heard in the investigation (which has not happened in this case) and that radar data normally are available within an hour. Later during the hearing, well-known lawyer Knoops made very clear that without the original raw (radar, satellite) data being available, the prosecution would have no leg to stand on.

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Wednesday, January 20, 2016

SIGINT, IMINT and MH17

(this post continues discussions in earlier posts on possible classified space-based observations of the shootdown of Malaysian Airlines flight MH17 over the Ukraine in 2014)

My position paper written for the Dutch Parliament Foreign Affairs committee hearing of Jan 22 (see my previous post) has a strong focus on infra-red detections of a missile by SBIRS. There are however a few other relevant aspects of Space Based observations in connection to the MH17 disaster that I could not cover in the space available to me for that paper.

In this post, I will provide some brief additional information about:

1) potential roles for IMINT satellites;
2) the positions of SIGINT satellites.


Optical and radar IMINT

1. optical IMINT

Both (unclassified) commercial and (classified) military satellite systems for high-resolution optical imagery (Image Intelligence, IMINT) exist, and both sources will be discussed below.

Optical and radar imagery obtained in the hours before, as well as during the event, might be used to look for missile systems, both on the Ukrainian as well as separatist sides of the front, in a wide circle around the site of the shootdown. It could also be used to verify the reconstruction of the purported movements of a Russian BUK system published by citizen journalist team Bellingcat, a study which is not uncontested. The Bellingcat team places the BUK in certain places at certain times, and if space-based imagery (either military or commercial) for those locations and times exist they could perhaps verify these claims.

The US military has one classified system of optical satellites with a (much-) better-than-1-meter capability: the KH-11 IMPROVED CRYSTAL/Evolved Enhanced CRYSTAL (aka 'Keyhole' or 'KENNAN') which reportedly (and theoretically, from known 2.4 meter mirror size specs) have a resolution in the order of  10-20 cm.

Mid-2014 this system consisted of four satellites: USA 161, USA 186, USA 224 and USA 245. All of these have been discussed on this blog before and are tracked by our amateur network.

We have accurate tracking data on three of these, USA 161, USA 224 and USA 245 for the days around 17 July 2014 and hence can pinpoint when these potentially had the crash area in their sight to better than a minute. For USA 186, which was actively manoeuvering around that time and for which we have a gap in our coverage form June to August 2014, pass times are a bit less certain and constrained to about 20-30 minutes accuracy.

First, we can positively affirm that one of the KH-11, USA 161 (2001-044A) actually had the Ukraine in its potential view during the incident at 13:20 UT:


click images to enlarge

Please note well: this does however NOT mean that USA 161 delivered imagery of the event. A number of factors should be taken into account:

1. the cloud cover at that moment, which might hinder imagery;
2. the crash site is located quite in the perifery of the satellites footprint area;
3. these satellites do likely not make images continuously, but only if commanded to do so, for specific areas of interest;
4. there is the question of whether USA 161 was still operational at that time. It was the oldest of the on-orbit KH-11, being launched 14 years earlier. Only a few months later it was de-orbitted, so it was clearly at the end of its lifetime.

In addition to their KH-11 system, the US military hires space on commercial high resolution optical IMINT satellites from the US commercial firm Digitalglobe (the same firm that supplies Google Earth with satellite imagery).  

Digitalglobe operates a number of satellites with a better-than-1-meter capability: Geoeye-1 (0.4 meter resolution), and Worldview 1, 2 and 3 (0.25-0.50 meter resolution). Most of the satellite imagery that the US Department of Defense supplies to the press (when briefing on the military situation in e.g. North Korea, Syria and Libya) comes from these commercial satellites.

Imagery from these same Digitalglobe satellites is also available commercially, to any interested party with money. And in addition to DigitalGlobe, the European company Airbus Defense and Space also offers commercial high-resolution optical imagery from its SPOT and Pléiades satellites. Pléiades 1A and 1B offer a 0.5 meter resolution. SPOT 5 and 6 offer a 2.5-1.5 meter resolution.

Accurate orbital data from non-classified sources are available for all the commercial imagers for 17 July 2014. The satellites in question made several daylight passes over the area in the morning of July 17, 2014, between 8:00 and 10:00 GMT, i.e. during the 3 to 5 hours before the shootdown, a period when the skies were still less clouded.

This does not mean that they necessarily made imagery of course. Yet any imagery these commercial Digitalglobe and Airbus satellites did make on July 16, 17 and 18 have the advantage that they are not "classified", unlike the US military data, meaning that they could be used and published without diplomatic problems by the Dutch government in the Dutch criminal investigation into the disaster.

I would therefore expect the Dutch OM to either buy or subpoena all potential Digitalglobe and Airbus imagery from these dates. They can be used to reconstruct missile system positions in the area (both on the Ukrainian, the separatist and Russian sides) within range of the shootdown location, and they can be used to hunt for missile transports (see my earlier remarks about the Bellingcat claims). The Dutch Air Force has an imagery analysis unit that is well suited to help with such an analysis. Including imagery from the days before and after the incident as well is useful to look for differences between imagery of these respective dates.


2. Radar IMINT

The US military has two systems for high resolution radar IMINT: the Lacrosse (ONYX) system of which currently only one satellite, Lacrosse 5 (2005-016A) is left on-orbit, and the radar component of the Future Imagery Architecture (known as TOPAZ), consisting of three satellites: FIA Radar 1, 2 and 3 (2010-046A, 2012-014A and 2013-072A). These systems should be capable of providing imagery with sub-meter resolutions, and like optical imagery, they can be used to look for the presence of missile systems in the area. They have the added bonus that they are not hampered by cloud cover, unlike optical imagery.

Apart from the USA, the German military also operates a radar satellite system, the SAR-Lupe satellites. The French military likewise operates its own radar satellite system, the Hélios system. Japan operates the IGS system (which includes both optical and radar satellite versions).

All of these satellites made passes over the Ukraine at one time or another on July 17 2014, so all of them might have provided useful imagery.  FIA Radar 3 made a pass right over the area in question near 11:43 UT for example, some 1.5 hours before the tragedy. FIA Radar 2 made a pass over the area at 18:00 UT, 4.5 hours after the shootdown. These are just a few examples.

Given what was happening in the area around this time, and the strong concern of NATO and the EU about this, it is almost certain that imagery of the area was collected by these US, German and French satellite systems.


SIGINT

My position paper briefly mentions that a number of countries have space-based SIGINT (Signals Intelligence) capacities. This does not only concern capacities for (for example) the NSA to tap into your cellphone and satellite telephone conversations: another important strategic aspect of space-based SIGINT is the capacity to detect radar and telemetry signals from enemy weapons systems. Such detections allow identification of the used weapons system (each system has its own 'signature'). They also allow, according to remarks by the then NRO director Bruce Carlson in a speech from September 2010 at the National Space Symposium, geolocation of the source of this radar signal (in the case of MH17: geolocation of the Target Acquisition Radar of the launch unit).

The US military has a number of SIGINT systems in several types of orbits: Low Earth Orbit (LEO) below 1500 km which allows coverage of a few minutes during a pass over a target; and Highly Elliptical Orbit (HEO) and geosynchronous orbit (GEO), which allow to monitor targets for many hours (HEO) to continuously (GEO) from distances of 36 000+ km.

France has a number of SIGINT satellites in LEO. China no doubt has SIGINT satellites too, as does Russia. For the moment I will focus on the US systems. I must ad that I did check the French systems as well but none of the French systems (ESSAIM and Elisa, both in LEO) had sight of the Ukraine at that time.

The US systems, under the catch-all codename ORION, include the TRUMPET-FO which move in HEO. One of them is USA 184, mentioned before in the discussion of SBIRS as it has a piggyback SBIRS capacity in addition to its main SIGINT role.

There are also the big MENTOR satellites in GEO, plus two MERCURY satellites also in GEO, and the older VORTEX system. Of these systems, TRUMPET-FO, MENTOR and MERCURY are certainly still active based on their orbital behaviour.

The map below shows the positions of those satellites in this series for which we have enough tracking data to allow a reconstruction of their positions and footprints on 17 July 2014, 13:20 UT and which had the MH17 crash area within potential view:


click map to enlarge

Again: this does NOT necessarily mean that all of these satellites were actively monitoring the Ukraine at that time. Quite a number of them will have been tasked on the Middle East.

Yet, given the strong NATO interest in events in the Ukraine at that time, notably the rising concern about advanced surface-to-air missile systems following the shootdown of a Ukrainian Antonov-26 a few days earlier, I would be surprised if none of them monitored the Ukraine at all.


A clarification note on the position of USA 184 (SIGINT/SBIRS)

In my position paper written for the Dutch Parliament Foreign Affairs committee meeting coming Friday, I included this map with the positions of three SBIRS satellites with view on the Ukraine at that time:


click map to enlarge

I should point out here that there is some leeway in the exact position of USA 184, depending on whether it made a corrective manoeuvre to maintain its Mean Motion of about 2.00615 revolutions/day or not since the day we last observed it.

If it did, its position would be slightly more westward compared to the position depicted above, i.e. in a position just north of Scotland rather than above the Norwegian coast:


Let me be clear: this does NOT influence the conclusions of my position paper: the MH17 crash site in both variants is well within the field of view as seen from USA 184, i.e. the satellite could potentially provide both Infra-red and SIGINT detections. In the interest of accuracy, I thought I should however mention it here.


Acknowledgement -  I thank Mike McCants (USA) and Ted Molczan (Canada) for discussions about satellite positions, notably concerning USA 184.

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Monday, January 18, 2016

Parliament hearing MH17, 22 Januari 2016

On 22 January 2016, the permanent committee on Foreign Affairs of Dutch Parliament will hold a full day of hearings/round table talks related to the shootdown of Malaysian Airlines flight MH17 on 17 July 2014. The hearings are in preparation for a debate about the Dutch Government's reactions to and actions with regard to the ongoing investigations into the disaster.

On the invitation of MP Pieter Omtzigt, I have been invited as an external expert to this hearing. The committee members want to get informed regarding the possibility of foreign (notably US) Space-Based military observations of the event, i.e. satellite observations by systems such as SBIRS. This is a topic I have covered earlier on this blog.

The agenda of the hearing (in Dutch) is here. On request of the committee, I have written a brief position paper on the topic (again: in Dutch) which can be found here.

Video of the hearing will be live-streamed through this link. My contribution is scheduled for 12:00-13:00 CET (11:00-12:00 GMT).

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Tuesday, January 05, 2016

In Memoriam: Pierre Neirinck, 16 Aug 1926 - 3 Jan 2016

Pierre Neirinck, 1926 - 2016 
(image taken by Daniel Karcher in 1992)

It is with much sadness that I write this memorial post. Yesterday, I was informed that Pierre Neirinck passed away last Sunday at the age of 89.

Pierre was a big name in our field and the nestor of our satellite tracking community. He was one of the very first amateurs to do serious positional observations on satellites, at the very dawn of the Space Age. Below are photographs which Pierre made at Malo-les-Bains, France, of a pass of Sputnik 2 on 13 April 1958, and of a pass of the Sputnik 3 rocket on 7 July 1958.  A positional observation of Sputnik 3 by Pierre done in 1959 can be seen here, courtesy of Ted Molczan.


Sputnik 2 (the one with Laika) imaged by Pierre Neirinck in 1958 just before re-entry

Sputnik 3 rocket over Malo-les-Bains imaged by Pierre Neirinck in July 1958

Before the Space Age started, Pierre studied the relationship between weather and solar activity and observed meteors, accompanied by his black cat Mickey "who mewed each time a meteor cross the sky" (private comm., 30-10-2012). His love of cats was something Pierre shared with a number of satellite observers.

Born in France in 1926, Pierre got the opportunity to turn his hobby into a professional job at the Satellite Orbits Group in Great-Britain from 1966 to 1982, where he was the driving motor behind the satellite prediction service at the Radio and Space Research Station (RSRS - in 1974 renamed to Appleton Laborotary) in Ditton Park, Slough. In this capacity he conducted orbital analysis and provided pass predictions to observers, as well as doing observations himself. He is explicitly mentioned in the memoirs of Desmond King-Hele ('A Tapestry of Orbits', Cambridge University Press, 1992), a renowned British satellite scientist at the RAE who greatly benefitted from the data flow generated by Pierre's activation of the amateur tracking network. His comments capture Pierre's extraordinary 24-hour passion and zeal for his work, remarking at a point that Pierre sometimes seemed to be two persons: "Pierre by day and Pierre by night" (King-Hele 1992, p. 138).

Pierre Neirinck (by day) at the RSRS Satellite Orbits Group in April 1971 (photo Tahsin Vudali)

After his early retirement in 1982 (due to a reorganization of the British governments' satellite tracking establishments), Pierre went back to Malo-les-Bains in the north of his native France.

This did not mean he stopped his activities: until very recently he still actively tracked satellites and analysed orbits, sometimes going as far as climbing on ladders to glimpse a low Keyhole pass over the rooftops, even when he was already well in his eighties. Moreover, behind the scenes he remained a central figure in the vitalization and coordination of amateur satellite positional observations, right up to just weeks before his death. He distributed COSPAR site codes to new observers and new observing locations (the last one he issued was for site 2752 on December 21, 2015, just two weeks before his death). He also distributed orbital analysis based on his own observations and the data we provided. Only the last two years or so, his declining health started to interfere and he was forced to stop active observing.

Active satellite observers, including me, until very recently received his charmingly idiosyncratic semi-daily e-mail dispatches (before my time, these were photo-copied notes distributed via surface post and fax - one of those is featured in Bob Christy's in memoriam for Pierre here). These e-mail dispatches featured his observations and orbital analysis (notably of the KH-11 'Keyhole' satellites), which were mostly done on an ancient Commodore computer, sometimes a note on his health or activities, old memories (often about WW II) as well as frequent brief ironic comments on world affairs, including geopolitics, sports (tennis notably), natural disasters, crimes in the news, scientific discoveries, and often presenting a brief tally of who had left our planet in violent ways the previous days. In private e-mails, he used to reminiscence about the squirrels and dragonflies at his old workplace in Ditton Park, and the sparrow visiting his window at Malo-les-Bains every morning.

Pierre was an enthusiastic and talented photographer, and his photographs sometimes featured in exhibits ( I regret that I can no longer find his fantastic self-portrait, called "auto-portrait", capturing himself in an automobile side mirror, which he once sent me).

Together with Ted Molczan, Pierre provided me with much encouragement when I started to seriously track satellites in 2005. In recognition of this, it was my immense pleasure to be able to have the IAU name one of my asteroid discoveries after him in 2008, asteroid (142014) Neirinck (see my blog post here). In response, he quipped about "his" asteroid that:

"I am glad that the Neirinck asteroid orbit has no chance to intercect [sic] the Earth in the near future. Otherwise,I would be potential Space criminal. My next problem is to plant 4 flags on it: French, British (because Satellite Orbits Group), US and Dutch flags." (e-mail 18 Nov 2008)




Pierre's contributions were deservedly recognized. In 2005, he received the Prix Jacquemetton d'Astronomie from the Société Astronomique de France. In November 2008 the French Academie Nationale de l'Air et de l'Espace awarded him a Bronze Medal for "his life’s work devoted to space observation". That same month, the International Astronomical Union on my initiative named asteroid (142014) Neirinck in his honour, as was already mentioned above.

Over the years, developments in Pierre's health frequently worried us, but he always recovered. We used to think he would live forever. With some Dutch/Belgian observers we were actually making plans to visit him at Malo-les-Bains one of these days. Alas, it will not be.

The satellite observers community will miss him, and remember him as one of the Great ones.

Rest in Peace, Pierre.

(information in this post is based on information provided by Bob Christy in his in memoriam here; by Ted Molczan in his in memoriam here; on e-mails from and private communications with Pierre over 2005-2015; and on King-Hele's book 'A Tapestry of Orbits'. The photographs of and by Pierre were all sent to me at some point by Pierre himself)

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Monday, December 14, 2015

Something (a fuel leak?) happened to the Chang'e 3 booster (2013-070B) late September-early October

Over the past year I have frequently reported on my observations of very distant space junk: objects orbiting at trans-Lunar distance. One of these objects, 2013-070B, the CZ-3C upper stage of the Chinese Chang'e 3 Lunar mission from 2013, is now showing something interesting.

flash cycle of 2013-070B on 11 Sep 2015 (click to enlarge). Stack of multiple images

2013-070B is tumbling and shows a very slow flash cycle (see various previous posts). Observations during the summer months of 2015, up to 14 September 2015, suggested a stable flash period of  about 423 seconds.

But somewhere between mid-September and late October 2015, things have changed. The first indication was from this fine series of data points which Krisztián Sárneczky obtained for me on 24 October 2015, using the 0.6-m Schmidt telescope of MPC 461 (Piszkéstető station of Konkoly Observatory, Hungary):

click diagram to enlarge


The flash period had suddenly dropped, to 384 seconds on 24 October 2015, and has further dropped to 364 seconds on 6 December 2015, based on a series of images I obtained with the help of Peter Starr from Warrumbungle Observatory (MPC Q65) in Australia.

2010-013B 2013-070B is hence suddenly tumbling at a faster speed than it used to do. The value is still dropping further, but the drop appears to be slowing down, as can be seen in the diagram below:

click to enlarge diagram

Such a sudden drop from a stable flash period to a shorter flash period can have a number of causes. A close approach to the Moon can result in a tumble periodicity change: but 2013-070B did not experience such a close approach during the relevant weeks, so that is not an explanation. The most likely explanation is that the booster developed a fuel leak.

Rocket stages always contain some remnant fuel in their tanks. Rocket fuel is often quite corrosive and slowly eats its way through the metal of the tank and booster. In addition, a meteoroid impact can puncture the rocket stage and tanks. When one of these two things happen, fuel vapor escapes from the rocket stage, and acts as a mini rocket engine, giving the object some extra momentum. This can either speed up or slow down he tumbling speed of the object.

We have seen this happen a number of times with rocket stages in Low Earth Orbit as well, and there is no reason why this could not happen to a rocket stage in a trans-Lunar orbit.

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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.

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Thursday, November 12, 2015

Small unusual artificial object WT1190F will impact in a few hours [UPDATED with imagery of actual impact]

click image to enlarge

(for an update with imagery of the actual impact of this object from a research plane, see bottom of post)

The animated GIF above was made from images which I took just a few hours ago with the 0.61-m Cassegrain telescope of MPC G68 Sierra Stars Observatory in Markleeville, California.

The moving object is WT1190F, discovered on October 3 this year by the Catalina Sky Survey. This small peculiar object will impact in a few hours from now (near 6:18 UT, Friday 13 November 2015) just south of Sri Lanka.

It is an unusual object that is not a Near Earth Asteroid but almost certainly a small (1-2 meter) artificial object. It is moving in the Earth-Moon system (i.e. in a very elliptic orbit around earth) and its orbit is under influence of Solar Radiation Pressure, which shows that it is very light weight for its size. This fact, and the geocentric rather than Heliocentric orbit with apogee at twice the distance to the Moon, suggests it is some piece of hardware from a past Lunar mission.

image credit: Bill Gray, Project Pluto


It is not clear from which Lunar mission this object is a relic: it could be from one of the American missions, but also Russian or Chinese. The object in question turns out to have been sporadically observed since 2009, as it is probably the same object earlier designated 9U01FF6 in 2009 and UDA34A3 and UW8551D in 2013.

Shortly after its (re-) discovery on October 3, Bill Gray noted that the orbit yielded impact solutions on November 13 near 6:18 UT. The predicted impact point is over the Indian Ocean, just south of Sri Lanka. Bill Gray has put up a FAQ for this object with maps of the orbit and impact location here.

image credit: Bill Gray, project Pluto

As this is a small, 1-2 meter sized and lightweight object, the impact is harmless. It will burn up in the atmosphere and likely nothing will reach the water surface. It provides scientists with a good opportunity though to observe what happens during a small asteroid impact, as the speed and entry angle of this object is quite similar (see also the project page here).

The astrometry obtained from my images makes, along with data by many other observers, a modest contribution to  establishing the impact point and time as good as possible.

1st UPDATE, 13 Nov 2015, 09 UT:  WT1190F is now toast for a few hours. South Sri Lanka seems to have been clouded out, but there are reports on Twitter of sonic booms from the re-entry heard in Sri Lanka. 

In response to some of the comments, I want to point out that WT1190F is/was not the only artificial object in a trans-Lunar orbit which we were/are tracking. Here you can find an earlier post (out of several) on tracking 2010-050B and 2013-070B, two rocket boosters in trans-Lunar orbits from the Chinese Chang'e 2 and Chang'e 3 Lunar missions.

2nd UPDATE,  13 Nov 2015, 13 UT:  The first imagery (below, three stills and the video) has just appeared of the actual impact near Sri Lanka, shot from a research aircraft organized by IAC / UAE Space Agency / NASA / ESA:


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