THE SECRET SPIES IN THE SKY - Imagery, Data Analysis, and Discussions relating to Military Space
SatTrackCam Leiden (Cospar 4353) is a satellite tracking station located at Leiden, the Netherlands. The tracking focus is on classified objects - i.e. "spy satellites". With a camera, accurate positional measurements on satellites of interest are obtained in order to determine their orbits. Orbital behaviour is analysed.
This blog analyses Missile tests too.
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.
The image above was made by me just after midnight of June 18-19, 2012. It is a single image taken with my new Canon EOS 60D and a SamYang 1.4/85mm lens (800 ISO, 10s exposure). It was shot from the center of Leiden town.
The image shows a 11 x 14 degrees wide field low in the south-southeastern sky, between 20 and 30 degrees elevation above the horizon. Diagonally over the image runs a part of the geostationary belt, at declination -7.4 deg for my location.
In this single image, as much as 30 mostly geostationary satellites are visible: 23 commercial geostationary satellites, 1 classified military geostationary satellite (Milstar 5, 2002-001A), and 6 rocket boosters.
I did a poor job with the focus of this image, resulting in a slight unsharpness (especially near the edges of the image). Yet, the number of objects nevertheless visible in this small piece of low southern sky is amazing!
This is just one of several images I took that night. Apart from Milstar 5, a number of other classified (military) geostationary satellites were imaged and astrometry on them obtained.
PAN in it's new position at 37.9 E
One of these objects is PAN (2009-047A), an enigmatic satellite I have written about before. Here is an image from June 18-19:
click image to enlarge
One of the curious aspects of this strange classified geostationary satellite operated by an undisclosed agency (see Dwayne Day's article in The Space Review), is that it is very frequently repositioned. It recently did so again (see my imagery of May 16, when it was still on the move). It has now stopped drifting and taken up position at 37.9 deg E (a position it has occupied before) not far from Paksat 1R, as can be seen in the image above. A stray Atlas Centaur rocket booster passed the area as well when the image was taken.
Vortex 4 and Mercury 2
Other classified objects imaged include the older geostationary satellites Vortex 4 (1984-009A) and Mercury 2 (96-026A), the latter of which currently also is on the move (it is probably being sent to a disposal orbit after reaching the end of its operational mission):
click image to enlarge
Vortex 4 (launched on 31 January 1984) and Mercury 2 (USA 118, launched on 24 April 1996) both are SIGINT (eaves-dropping) satellites, with the Mercury being a further advanced version of the Vortex.
In addition, a newer SIGINT satellite was imaged as well, Mentor 4 (2009-001A, one that frequently features in this observational blog, as it is bright and easy to observe), and the object designated by our amateur network as UNK 060616 (probably an old r/b).
Prowler, AEHF 1 and DSP F15 imaged from Winer observatory, USA
While the above imaging was all done from my home in the Netherlands, I also imaged a few objects 'remotely' using the UoI Rigel (MPC 857) 37-cm Cassegrain telescope at Winer Observatory, Sonoita, Arizona, USA.
The enigmatic Prowler (1990-097E), a clandestine launch from Space Shuttle mission STS-38 which has featured on this blog more often (read the intriguing story of Prowler here; plenty of suspense!) was imaged on June 19 and 22. On June 19 I also imaged the military communications satellite AEHF 1 (2010-039A), and on June 22 the old DSP Infra-red early-warning satellite DSP F15 (1990-095A). Images of these objects below:
click images to enlarge
Comet 185P/Petriew
In addition to all these satellites, two Solar System Minor Bodies were imaged: 2012 LZ1 and 185P/Petriew.
I posted imagery of the June 15 fly-by of Near Earth Asteroid (NEA) 2012 LZ1 here before in my previous post, and obtained more astrometry on this object on subsequent nights. In addition, I obtained some imagery on the faint periodic comet 185P/ Petriew on June 22. Below is a stack of 5 images of 45s exposure each:
click image to enlarge
Not a pretty picture, but the comet was near magnitude +17 to +18! My astrometry has been included in MPEC 2012-M33 (22 June).
New camera: a Canon EOS 60D
I had completely forgotten to mention this: during the second half of May, my EOS 450D camera broke down. During a macro-session on Dragonflies, the shutter broke. Much to my regret.
I had the choice between having the shutter repaired (expensive), or buying a new camera. I choose the latter option, as the new generation of EOS cameras performs notably better than the 450D, especially in performance at high ISO (less noise). So I decided to upgrade.
The choice I made was for the Canon EOS 60D, an 18 MP DSLR with Digic IV processor. So far (and having mostly used it for "normal" photography for now) I very much like it!
Before I can use it on satellites in Low Earth Orbit, I'll first have to complete a calibration program with the camera. This calibration entails the delay between the moment you press the shutter button and the exposure is actually taken; and the real duration of exposures (a "10 second" exposure is not exactly 10.00 seconds). I have some preliminary calibration results by now, but it will take some time before I have final results and can start to use the camera regularly on satellites. For geostationary satellites (where the timing accuracy isn't that much of a factor; rather the astrometry is) the preliminary results I have mean I can already use it (as has been done, see this post).
Monday evening was a nice clear evening with a very transparent sky.
I observed the NOSS 3-5 duo (11-014 A & B), which was captured in a very fine image with a stray nearby, the rocket from the Kosmos 1697 launch (85-097B). De double parallel trail above is the NOSS duo, the single trail under an angle is the Russian rocket (bright star near trails is Deneb):
click image to enlarge
I also took opportunity of the transparent sky to target some geostationary objects low in the southeast. Targets were PAN (09-047A) and Mentor 4 (09-001A):
Yesterday evening (Saturday 29 January) some satellites seemed to be in love with the Pleiades. In a somewhat hazy sky, I observed Lacrosse 3 (97-064A) cruising near the Pleiades and Hyades in twilight, and half an hour later watched the NOSS 3-4 duo (07-027 A & C) cruise right through the Pleiades.
Below are the resulting images. The top image of the NOSS duo cruising through the Pleiades (movement is from top to bottom, with 07-027A leading) was made using the Canon EF 100/2.8 Macro USM lens: the images of Lacrosse 3 were made using the EF 50/2.5 Macro lens.
click images to enlarge
The FIA Radar 1 (10-046A) was imaged as well. Unlike a few nights ago, it did not flare.
The previous night had a better quality sky, so I targetted a few geostationary satellites low above the horizon. Classified geostationary targets imaged were PAN (09-047A), Mentor 2 (98-029A), Mentor 4/USA 202 (09-001A) and the Milstar 5 r/b (02-001B). A number of commercial geostationary satellites were captured as well.
Below image, taken with the Carl Zeiss Jena Sonnar MC 2.8/180mm, shows PAN with the nearby commercial geostationary Yamal 202 (03-053A).
click image to enlarge
The image below, taken with the EF 2.5/50mm Macro, shows Mentor 2, with the stars of Orion's belt and Orion's nebula M42 at left:
click image to enlarge
I also accidentally captured a mag. +2.5 sporadic meteor in one of the images taken with the Carl Zeiss 180 mm (FOV only 5 x 7 degrees!):
Yesterday evening was a very dynamic evening, where conditions changed from clear to clouded to clear in matters of minutes.
Besides the unexpected recovery of a lost classified geostationary, I also observed a number of other geostationary satellites, and another fine flare of the close duo TerraSAR-X and TanDEM-X (for an earlier observation, see here). They flared to mag. -1 at about 17:18:20 UTC, yielding the image below:
click image to enlarge
Movement is from left to right, with TerraSAR-X leading. The distance between the two objects was 3' (arcminutes).
Below two images show the couple Mentor 4 (USA 202) and Thuraya 2 imaged with the Carl Zeiss Jena Sonnar MC 2.8/180mm; and Mentor 2 imaged with the Canon EF 2.5/50 Macro.
SpaceX's launch of the Zuma satellite on 8 January was interesting, and not just because of the ongoing saga of whether it failed or not (see a previous post).
The odd 50-degree orbital inclination is another element that made this launch interesting (see discussion in my pre-launch post here: sightings of the Falcon 9 Upper Stage over Sudan after launch later confirmed this orbital inclination).
New ideas started to form post-launch after the Falcon 9 sightings from Sudan made me realize that while it indeed was launched into a 50-degree inclined orbit, the orbital altitude (900-1000 km apogee) was higher than I initially expected, making a proposed link to USA 276 unlikely.
As @Cosmic_Penguin notes, the publication specifically discusses ~50-60 degree inclined, ~1000 km altitude orbits. And it is all about Space-based Radar.
The report pitted several radar sat constellation configurations against each other, but all of them assumes the satellites being in a 1000 km high, 53 degrees inclination orbit. That's very close to the current search estimation of ZUMA's orbit by @Marco_Langbroek. 🤔 (2/2)
I had just been looking into the coverage of the Zuma orbit, and it lines up with content in that report.
The map below is a ground coverage map of Zuma, would it have been alive and well. One of the uses of a ~50 degree inclined ~1000 km altitude Space Based Radar satellite mentioned in the report, is for shipping surveillance.
Indeed, a satellite in a Zuma-like orbit would basically cover all Ocean surfaces, except for the high Arctic and Antarctic, which are not that interesting for the purpose discussed below (moreover, the Arctic is extensively covered by groundbased and airborne radar).
click map to enlarge
A (Radar) satellite in this kind of orbit therefore would be very useful to keep track of illicit shipping movements on the High Seas.
Think stuff like embargo-runners, e.g. embargo-breaking shipments of coal and oil to for example North Korea, illegal weapons exports from North Korea, oil exports from Syria, illicit weapons transports to the Middle East, and human trafficking as well as drugs shipments.
Ships engaged in such illegal activities sometimes turn off their transponder, making it harder to track their whereabouts once out of sight of landbased shipping radar (see also the story about one particular embargo-breaking ship here). The classified US NOSS duo ELINT satellites and similar Chinese Yaogan triplets are meant to track ships from passive radiosignal crosslocation, but when a ship displays strict radio silence, these systems will not detect them either. But Space-Based Radar will.
Embargoes have become an important geopolitical tool when outright war is deemed not an alternative. We currently see embargoes enforced with regard to for example Syria and North Korea. Means to enforce embargoes including detecting and stopping potential embargo violations therefore have become important. Human trafficking and drugs trafficking are growing geopolitical problems as well.
So was Zuma meant to be an (experimental, i.e. a technology demonstrator) version of such a Space Based Radar for Ocean shipping surveillance? It is an option.
What might argue against it is the extreme secrecy surrounding the launch. Very few details were made public about the Zuma payload, the Agency operating it was not disclosed, and the launch was announced very late.
For all of this, explanations can be sought, but that admittedly all is "special pleading". For example, maybe the secrecy is there because the mission involves cutting edge experimental Radar technology. Or the secrecy could simply be the result of the "secrecy cult" in some parts of the US Government going over the top. Or it could point to operation by an Agency that wants to keep this operation on the down low - e.g. the CIA. And I can think of a few more - much more outlandish, which is why I won't mention them here - potential reasons.
We have seen this kind of secrecy before with PAN (and its later sister ship CLIO), with Prowler, and more recently with USA 276. All of these were experimental satellites doing unusual things: PAN roved between, snug up to and eavesdropped on commercial geostationary satellite telephony satellites. Prowler was an experiment for covertly inspecting other geostationary satellites on-orbit. And USA 276 remains mysterious but a series of very close encounters to the International Space Station suggest it might be a technology demonstrator for observing rendez-vous manoeuvres in space.
Zuma (the more so now it might have failed) also strongly brings the infamous USA 193 satellite to mind, although there we do know that it was a satellite for the NRO, and likely an experimental radar satellite [edit: see added note 2 below].
Nevermind what Zuma really was meant to be, and who was to operate it: the message to take home is that High Seas shipping surveillance is a potential and viable role to keep in mind for any future satellite launched in a ~1000 km altitude, ~50 degree inclined orbit.
Added note 1: Cosmic Penguin pointed out to me that this was also earlier brought up in a forum post by Ed Kyle.
Added note 2,12 January 2018: This article suggests Zuma might be an electro-optical/SAR hybrid and a follow-on to the infamous USA 193:
"Second, the Northrop Grumman satellite may be a follow-on to another failed satellite US 193. [...] ....,
a source with direct knowledge of the program told me it was a blend of
radar and electro-optical and would not provide any more detail than
that. A source with wide knowledge of classified space programs has told
me that the Northrop Grumman-built Zuma may be the next iteration of
this. Both were apparently experimental satellites, in that they were
not part of a large constellation of similar satellites."
Such a spacecraft would be well suited for the purpose indicated in this blog post.
I hardly can't believe it: but today, this blog turns
15 years!
It all started very humble. The very first post on this blog, titled "Dutch weather sucks!", went up on 6 August 2005. It was a very simple, brief message, noting how I was defeated by weather that night.
Most of the early posts on this blog back in those days were such very brief and simple notes (but then, blogs back in those days were much more simple affairs). It were very basal, verbatim reports on my nightly observing activities. A lot of it was bitching on the proverbially bad Dutch weather (seriously: for a satellite tracker I am situated in one of this Worlds worst locations considering weather. And light pollution).
My equipment back in those days was very simple too: nowadays it is much more sophisticated (but still, all is done with off-the-shelf equipment that in itself need not be very expensive).
This blog is what I would call a Niche Blog: one that is dedicated to some
weirdly esoteric field of interest. There are literally only a handfull of amateurs
Worldwide who are actively tracking satellites, maybe 15 active observers altogether (but a lot more who like
to read and talk about it). Space Situational Awareness, to use the professional terminology, is a decidedly geeky field.
The X-37B military space plane OTV 6 (click image to enlarge)
Therefore, it has always surprised me how many readers my blog draws, especially when something special is going on. In the latter case, this blog can draw an audience of thousands of readers per day. On a more typical day, it would be one- or twohundred per day at most.
Started in August 2005, this blog would grow over the next 15 years to become a much more mature, well established and apparently well-respected blog with a dedicated following of fellow satellite trackers from the SeeSat-L mailing list as well as an assorted lot of sundry general Space enthusiasts, Space Situational Awareness professionals, journalists, Missile geeks, and other people who somehow find their way to this blog.
And Spooks too. IP logs show that this blog has been visited by amongst others the CIA, the NSA and the North Koreans. It made me joke to my friends about black helicopters, unmarked SUV's, and I tongue-in-cheek asked them to send clean underwear to Gitmo in case I would suddenly vanish.... Another noteworthy, unexpected visit some years ago, was someone from the Executive Office of the US President (this was at the time that a malfunctioned Japanese spy satellite was about to come down).
Fifteen years ago, I'd never dreamt of such a wide audience. What originally was simply an on-line observing log (as reflected in the name), has by now become a well established military Space related OSINT blog.
Photography and data visualizations have been, and will continue to be, a very important part of what I write for this blog. While functional (astrometry), I always strife to make my imagery visually attractive as well.
My imagery inspired the artist and investigative journalist Trevor Paglen, so he told me, to create the chapter "The Other Night Sky" in his photobook Invisible. Covert Operations and Classified Landscapes.
With Trevor Paglen in Amsterdam in 2018
So how did it all start? During the Nineteen-nineties, previous to my interest in satellites (which came from an interest in satellite reentries), I was an active meteor observer within the Dutch Meteor Society. Back in 2005 I realised that the software we used to astrometrically measure meteor images, would be suitable for measuring positions on satellites in images too. Around that time I also discovered this weird but fascinating world of observers tracking classified satellites! So I started to experiment with that, and after a period of trial-and-error and discovering what was important (accurate timings and camera calibration!), I started to get usefull results. Soon, I became a regular contributor of positional measurements on classified satellites to the Seesat-L list.
Starting simply with a compact camera (a Canon IXUS gifted by a friend), the equipment has grown over the
years. A significant quality change came when I landed a post-doc, got some money and turned to using a DSLR (initially a Canon EOS 400D; currently a Canon EOS 80D) and an over time growing suit of suitable lenses (Canon EF 2.0/35 mm; Canon EF 2.5/50 mm, Samyang 1.4/85 mm; Samyang 2.0/135 mm; and in the past also a Zeiss 2.8/180 mm).
For Low Earth Orbit, I now preferably use a sensitive video camera (a WATEC 902H) with either a Canon 1.8/50mm or Samyang 1.4/85 mm lens, and a GPS time inserter, as timing remains the bottleneck of using a DSLR. The DSLR is now mainly used by me for astrometry on high altitude objects (HEO and GEO), and for obtaining pretty pictures of Low Earth Orbit objects.
Over the past few years, radio was also added as an observing tool (although mostly focussing on Human Spaceflight communications and capturing weather satellite imagery).
Click image to enlarge
As this blog matured, and I gained more insight into spaceflight dynamics (graciously helped along by people like Ted Molczan), the posts became more elaborate. The scope widened. I started to publish analysis, and these started to gather attention. A few years ago, my interest in the North Korean Space program expanded into an analytical interest into the North Korean missile program (which introduced me to the funny lot of people that populate the Missile Twitter community), and ICBM tests in general.
At one point, some of my analysis outgrew this blog, resulting in more formal articles written for The Space Review and The Diplomat (see links in the sidebar). Apart from my blog posts and articles, I also frequently present imagery and small preliminary analysis through my Twitter account.
Journalists increasingly found me, and I started to get quoted and interviewed by websites, printed news media, TV stations and radio stations in the Netherlands, Germany, the UK and the USA. I even appeared in a PBS documentary, being interviewed by Miles O'Brien about an analysis of North Korean launch imagery.
with Miles O'Brien for a PBS documentary, December 2017 (aired in February 2018)
When I started this blog 15 years ago, I never dreamt it would take off this way. It has been a surprising journey: starting as a rank amateur 15 years ago, I am now, partly thanks to this blog, actually employed as a Space Situational Awareness (SSA) consultant at Leiden University in a project with the Space Security Center of the Royal Dutch Air Force. It goes to show how things that start small and simple, over time can grow very serious.
The shift towards more professional SSA involvement was the result of a terrible tragedy. On 17 July 2014, a Malaysian Airlines airliner, flight MH17 flying from Amsterdam to Kuala Lumpur, was shot down over Ukraine. 298 people lost their lives, including 192 Dutch. For me this tragedy was extra unnerving at the time, as my girlfriend and I were about to fly the same route with KLM/Malaysian only three days later...
I wrote a blog post about the tragedy (the first of several) detailing how Space-based data from the classified SBIRS satellite constellation and various SIGINT satellites might shed light on where, and by inference by whom, the missile was launched.
This blog-post was subsequently picked up by a Dutch Member of Parliament, Pieter Omtzigt, who then contacted me. He used the information I provided as a base for questions in a Parliamentary committee session in 2015, and next invited me to give expert testimony in a Hearing of the Permanent Committee of Foreign Affairs of Dutch Parliament on 22 January 2016. It was part of a large, a day long session that included Radar experts, hotshots from Air Traffic Control, the Intelligence Services, and experts in international Law. I had to write a position paper for it, and during the session, give a brief presentation and then answer questions by Parliament members.
Giving testimony at a Permanent Foreign Affairs Committee hearing on MH17, 22 January 2016
This caught the attention of the then brand new Space Security Center of the Royal Dutch Air Force, who contacted me a few days after the hearing. They were very interested in what I was doing, especially since they wanted to create their own tracking capacity. This led to several meetings and eventually two projects, one completed and one currently running. The astronomy department of Leiden University hired me as a consultant as part of these projects. What started as a hobby, turned professional (this has happened to me before by the way: with meteorite research. That started as a hobby too but led to a research job at the Dutch National Museum of Natural History, and a 30-page scientific paper in Meteoritics & Planetary Science).
Those who have followed this blog for several years, know that the content is ecclectic (mirroring my wide interests). Apart from imagery and analysis of classified satellites, it also features posts on missiles, and occasionally features more off-topic subjects such as meteoric fireballs, meteorites, comets and asteroids.
This reflects my wide and varied interests, which is apparent in much of what I do. I am a scientist with a PhD in Palaeolithic archaeology, but I have worked as a scientific researcher in totally different fields too, including Planetary Geology/Meteoritics and now also SSA.
So that is the story of how this blog came into being, and how it changed my life.
What were some of the highlights of those 15 years writing this blog and doing OSINT analysis on classified space and missiles? Among the more notable for me were:
The analysis of amateur observations of the SIGINT satellites PAN/NEMESIS 1 and MENTOR 4 in the context of leaked Snowden files, leading to a publication in The Space Review;
The analysis of a Trident-II SLBM test captured by chance on photograph by an amateur astronomer from La Palma, in the context of other Atlantic Trident tests;
It is time for a summary of the observations conducted in 2012.
I have been less active in 2012 than in previous years, logging about half the number of observational nights and obtained positions. The number of classified objects tracked however was somewhat higher.
Number of observing nights:44 Number of obtained positions:555 Number of classified objects tracked:50
These data compared to previous years:
(click diagram to enlarge)
As in previous years, springtime saw most observational activity:
(click diagrams to enlarge)
The following tables give a summary of the objects observed (with the
"obs" column refering to the number of positions obtained on the
object):
(click tables to enlarge)
Just for fun, I plotted all obtained positions on an RA/DEC map:
(click diagram to enlarge)
So, what went on and what was special in 2012?
I continued my coverage of PAN and other geostationary satellites (well visible near declination -7.4 in the diagram above). On May 16, an unknown object in GTO (Unknown 120516) was briefly detected. In November, I found an unidentified geosynchronous object at 48 E that turned out to be the relocated object Mercury 1.
In the last days of March, I filmed and photographed ESA's cargoship ATV-3several times. This included vudeo and photographs less than 20 minutes after launch, when it made a deep twilight pass over Leiden. I photographed it again in September, after the ATV decoupled from the ISS again. Both times, my video and photography was featured on ESA's website.
2012 was the year of Dutch astronaut André Kuipers' 6-month stay at the ISS. I attended a live in-flight video contact at ESA/ESTEC Noordwijk on May 29. Earlier, on March 16, I listened in live to a radio contact between Kuipers (onboard ISS) and a Dutch school class with my radio receiver.
Live radio receptions were also obtained during the flight of Soyuz TMA-04M on May 16.
Mid-2012, the Japanese spy satellite IGS 1B performed an uncontrolled reentry, and over the spring and early summer I closely followed its demise, which finally took place on July 26, when I was on hollidays in Italy.
Among the new launches tracked was NROL-36, the new NOSS 3-6 duo (see here and here) launched in September. NROL-15 (a new Mentor, Mentor 5) was also tracked
October was very sad, as it saw the death of our cat, Pippi, on October 30. As related in the link, Pippi was a frequent companion during my observing sessions.
November 2012 was special, as I received the 2012 Dr J. van der Bilt Prize of the Royal Dutch Astronomical Association (KNVWS) on November 10 (see photographs here and video here).
December saw some unusual visitors to this weblog, connected to North Korea's first successful satellite launch.
2012 was also a good asteroid year too. I discovered 3 new asteroids: 2012 SM58 in September using the 0.61-m telescope of Sierra Stars Observatory and a number of objects with Krisztián Sárneczky in the Piszkéstető (Konkoly) survey.
I should have done this analysis earlier but did not have the time available until now. What follows now is a quick and back-of-the-envelope kind of calculation, but in my (not so) humble opinion it is adequate to the question at hand.
The map above gives a quick (and not particularly accurate) back-of-the-envelope reconstruction of the fireball trajectory. It is based on trajectory descriptions from Bussloo in the Netherlands and Dublin in Ireland: by taking reported altitudes (with respect to stars) and general directions of reported start and endpoints, and an assumed altitude of 50 km, the trajectory above is what approximately results. (update 19:10 UT, 24 Sep: an updated version of the map is at the bottom of this post).
The resulting trajectory is some 1000-1200 km long. In what now follows, I have taken 1100 km as the distance travelled by this fireball.
Observers near the western and eastern ends of the trajectory would probably not see the complete trajectory. Observers approximately mid-way, in mid-Britain, would potentially see most if not all of the trajectory (from experience I know you can see bright fireballs from distances of 500 km).
Observers report durations between 20-60 seconds: most video's on the web suggest a 40+ seconds duration.
It would take a reentering satellite travelling at 8 km/s (the orbital speed at decay altitudes) about 138 seconds or roughly 2.25 minutes to travel this distance. While the reported fireball durations are long, none of the reports nor videos comes even remotely close to that value.
A meteoric fireball travelling at the lowest speed possible for such an object, 11.8 km/s, would take 93 seconds to travel that distance. This is still longer than almost all of the reports suggest, but clearly getting closer.
If we take an estimated duration of 60 seconds, the 1100 km trajectory length results in a speed of approximately 18 km/s.
18 km/s is a very reasonable speed for a slow, asteroidal origin fireball.
(it is, let me repeat, also way too fast for a satellite reentry).
Meteorite dropping fireballs typically have speeds between 11.8 and 27 km/s. A speed near 18 km/s sits squarely in the middle of that speed interval.
(update: diagram added 14:45 UT, 24 Sep)
(click diagram to enlarge)
The 60 seconds probably represents the upper boundary value for the duration of the fireball. If we take a shorter duration of 40 seconds, the speed already increases to 27.5 km/s.
This quick back-of-the-envelope reconstruction therefore shows that this must have been a meteoric fireball, quite likely of asteroidal origin, and we definitely can exclude a satellite reentry.
The fragmentation described and filmed is not unusual for meteorite dropping fireballs (see the video's of the Peekskill meteorite fall in my previous post). The object probably entered the atmosphere under a very shallow angle, which together with the slow speed explains the unusually long duration of the event.
Note 2: on how I made this quick and (emphasis) rough trajectory reconstruction. I took observations that contain clear sky locations: e.g. a sighting from Dublin stating it went "through the pan of the Big Dipper"; the description from Bussloo observatory in the Netherlands; and later adding a.o. a photo from Halifax, UK, showing it just above the tail of Ursa Major. These descriptions can be turned into directions and elevations. Next, I drew lines from these sighting points towards the indicated directions, marking distances roughly corresponding to 30, 50 and 80 km altitude as indicated by the observed elevation [ distance = altitude / tan(elevation) ]. Near the start of the trajectory I marked 50 and 80 km, for Britain and Ireland I marked 30 and 50 km. These points then provide you with a rough trajectory. From Dublin the object passed through North towards west. From Bussloo the object started NE (azimuth 60 degrees): these are important points of information too as it shows that the object started at least as far east as the Dutch-German border (and more likely over Sleswig-Holstein in N-Germany) and had its endpoint at least as far west as the northern part of Ireland.
Above: Updated map version, 24 Sep 19:10 GMT , also showing the principle of how it was reconstructed for three sighting locations. With thanks to Ramon van der Hilst for providing more detailed information on sky trajectory as seen from Bussloo (NL) on request.
The picture above (10s exposure taken with a Canon 450D and SamYang 1.4/85 mm lens) shows the classified military Radar reconnaissance satellite FIA Radar 1 (10-046A) sailing smack through the Pleiades last Friday.
Friday evening started clear, and I took the opportunity do so some observing. Using the SamYang 1.4/85 mm and the Carl Zeiss Jena Sonnar MC 2.8/180mm, I not only obtained the picture of FIA Radar 1 above, but I also targetted some geostationary satellites, imaging several of them in Orion.
Among the targets were the classified military communication satellite Milstar 5 (02-001A), the SDS data relay satellite USA 227 (11-011A) and the SIGINT satellite Mentor 2 (98-029A). Two other classified objects were captured as by-catch of these objects: the SIGINT satellite Vortex 6 (89-035A) and the object "Unknown 110623" (11-674A), an amateur-discovered object in GTO that is probably a spent rocket booster of a military launch. Note how it created a tiny trail in the image below as it was moving northwards through Orion.
The images below show these objects. Milstar 5, Vortex 6, UNK 110623 plus the two non-classified commercial communication satellites Eutelsat W2 (98-056A) and Intelsat New Dawn (11-016A) are all in the same 10-degree wide 85mm image. The stars of Orion's belt are visible in the top of the image, and Milstar 5 is close to the Orion Nebula. Orion's belt stars are visible at left in the Mentor 2 image as well.
click images to enlarge
In one of the other images taken last Friday evening, another commercial geostationary communication satellite, Intelsat 4 (95-040A) was captured while it briefly flared brightly at about 18:58:30 UTC (27 Jan).
The FIA radar and a number of geostationary objects (Mentor 2, Mentor 4) and the NOSS 3-3 r/b were imaged by me two weeks earlier as well, observations on January 14 and 15 which I had not reported here earlier. I also tried to relocate PAN, which recently has been relocated again but so far has not been recovered, although both Greg in South Africa and I in the Netherlands have tried.
Among the family of classified satellites, three stand out as more mystifying than the rest: Misty 1 & 2, PAN, and Prowler.
The latter has long existed in the realm of rumours only. It was launched by Space Shuttle Atlantis on mission STS-38, which was a classified DoD mission launched on 15 November 1990. Officialy only one satellite, USA 67, was launched from the Atlantis payload bay. This is believed to be a geostationary SDS communications satellite, SDS 2-2.
STS-38 mission patch
USSTRATCOM released catalogue numbers (but no public orbit) for three objects connected to this launch: the SDS satellite USA 67 itself (90-097B, 20963) plus two rocket bodies (90-097 C & D, 20964 and 20965).
The latter was puzzling, as it is one toomany (see the discussion by Ted Molcan here), This was the start of the idea that a second, unacknowledged object was launched by STS-38 as well.
In 2004 an NBC journalist referred to such a secret payload by the name of Prowler, in a news-item discussing a Senate debate about a classified spy satellite program drawing criticism for massive cost overruns. The same journalist, citing anonymous sources, did so again in 2007.
According to these stories, Prowler was an experimental satellite used for close inspection of other (non-US) satellites in geostationary orbit (see discussion here), reportedly coming to within decimeters of some satellites. There are suggestions that it was a test of technology which, in wartime, could be used to sabotage enemies' space assets. It was also said to employ stealth technologies to evade easy detection.
Meanwhile, US amateur observers Ed Cannon and Mike McCants had discovered an unidentified near-geostationary object in July 1998. As time progressed and more and more ISON and amateur-discovered objects could be identified with specific launches, this one was one of few left unidentified. This in turn led to suggestions that the object in question was the rumoured unacknowledged STS-38 launch, Prowler. It was likely discovered only after its active lifetime ended, and it was put in a disposal orbit (see below).
Since then, a long term analysis by Ted Molczan has strengthened this identification. The object has al the right characteristics in terms of brightness behaviour and orbital behaviour. It currently is in an unusual librating disposal orbit that seems devised to keep it out of reach of Soviet tracking facilities (see discussion in depth by Ted here). In a second analysis, Ted showed that STS-38 indeed had the opportunity to launch this object and some tell-tale clues to that are present in the manoeuvering history of STS-38 Atlantis. The whole history of the object, from launch onwards but also including the final disposal orbit when the stealth character of the object was lost, was designed with low detectability by Soviet tracking facilities in mind (see Ted's discussion here).
The object now resides in a currently 13-degrees inclined orbit librating between 73 W and 136 W, putting it over the eastern Pacific, with visibility from the western United States. Over the past two weeks , I imaged it a number of times, using the 0.61-meter "remote" telescope of Sierra Stars observatory in California. Below is one of the better images, shot on the morning of July 6th:
The "Supermoon" of yesterday was not my only observational target. The sky was very transparent, and hence even with this full "supermoon" low in the southeast, conditions were fine for satellite observations.
I imaged two Lacrosses and two KH-12 Keyholes: Lacrosse 3 (97-064A), Lacrosse 5 (05-016A), USA 129 (96-072A) and USA 186 (05-042A). In one of the images, Rubin 4/SL-8 (03-042B) was captured as a faint stray.
Both of the Keyholes and one of the Lacrosses (Lacrosse 3) flared: KH-12 USA 129 did so while the camera was open, yielding the picture below (note the Hyades at the bottom):
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Flare times:
USA 129: 20:29:08 UTC USA 186: 20:14:40 UTC Lacrosse 3: 19:52:40 UTC
Below images show Lacrosse 3 ascending and brightnening over the chimney (with Canis minor in the upper right corner: this was just before it flared), and Lacrosse 5 descending through the tail of the Big Dipper (the fuzzy arc is a reflection from a nearby lightsource):
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These observations were all done just after returning from a trip to Belgium, where we had a meeting of the BWGS (Belgian Working Group Satellites). It was a small but nice gathering (six attendants, including this author). Below some pictures showing me (left) and Leo Barhorst (right): and BWGS president Bram Dorreman (all pictures taken by Koen Geukens):
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On the agenda were amongst others the future of flash observations; the observations of flaring geostationary satellites earlier this month; while I did a very short photo-presentation on the recent PAN relocation story (see also here). Our host that day was Koen Geukens.
