A farewell to GOCE

In the past, I have observed ESA's gravity probe GOCE (2009-013A), the Gravity field and steady state Ocean Circulation Explorer, a number of times (e.g. here, here, here, here and here), usually as a rather faint object producing brighter specular flares near culmination.

 click image to enlarge

This weekend I tried again, spurred to do so by some people at ESA's ESOC in Darmstadt. The reason was that GOCE does not have much lifetime left. It's ion engine will run out of Xenon and cut-off somewhere mid- to end October, and the expectation is that the spacecraft will then re-enter and disintegrate in the atmosphere within 2 to 3 weeks. Some 250 kilo of the one-ton spacecraft might survive re-entry, divided over 50+ fragments.

The Goce orbit already had been brought down in November 2012: its orbital altitude currently is no  more than 225 km. As a result, it currently zips across the sky at high speed. Because of the low altitude, it is visible in twilight or very shortly after twilight only.

The image above shows GOCE over the roof of my home in Leiden center in deep evening twilight of  Sunday 29 September. It was visible with the naked eye, but only barely.

The image was shot with an EF 2.0/35mm lens and because of the bright twilight sky I used a short exposure of 2.5 seconds. The elevation of the spacecraft was around 40 degrees, passing east of me. The sky background shows stars in Andromeda: about halfway of the chimney and the GOCE trail you can see the fuzzy glow of M31, the Andromeda nebula.

I had also tried to image the spacecraft the evening before (Saturday the 28th), but Murphy struck. I was a bit late in checking for passes that day (in twilight already) and discovered that the only visible pass would happen within minutes of me checking for passes! So I ran outside, grabbed the camera, slammed it on the tripod, aimed it...and forgot to take off the lens-cap....

That particular pass, in a somewhat darker late-twilight sky and at a higher elevation through Cygnus, was a nice one, where GOCE was clearly visible to the naked eye. GOCE was racing through the sky, about the fastest you will ever see a satellite move in the sky. Quite apt for "the Ferrari among the satellites"!

This might have been my last view of GOCE ever: over the coming days the passes will become increasingly more unfavourable for my location.

It will be interesting to follow the satellite to decay once its engine has cut off. The ESOC people told me they will try to put it in a fine-pointing mode just before it does so, but there is a possibility that at one point it will lose attitude and will start tumbling.

ISS and Cygnus

On September 18, Orbital Science Corporation launched an Antares rocket from Wallops, with the Cygnus COTS demo as payload. Just like SpaceX-es Dragon, the Cygnus is a commercial cargoship built to bring cargo to the ISS as part of  the Commercial Orbital Transportation Services (COTS) initiative. The September 28 launch is the inaugural demonstration flight of the Cygnus.

Initially Cygnus was to dock with the ISS on September 22nd, but a communication problem between the ISS and the Cygnus board computer caused a delay. Next the launch and docking of Soyuz TMA-10M bringing a new astronaut crew to the ISS on September 25 intervened, with the result that the Cygnus docking was rescheduled for September 29th.

click image to enlarge

In the early morning of September 29th, around 4:01 UT (6:01 am local time), ISS and the Cygnus COTS demo cargoship made a 40-degree pass in the southern sky as seen from Leiden. I had no idea how close the pair would be before actually observing the pass. It turned out to be close, the two spacecraft passing some 15 seconds after each other. The ISS was leading, Cygnus following.

Shortly after emerging from eclipse, the Cygnus was reasonably bright (mag. +3) and visible by the naked eye. But it quickly lost brightness, and by the time the pair entered the FOV of my camera, which I had aimed at Orion, Cygnus was no longer visible to the naked eye.

As a result, the image above (taken with an EF 2.0/35mm lens) is not the best: I had to pull a full suite of post-edit tricks to make the very faint trail of the Cygnus stand out a bit better. The image shows the pair traversing the area of Orion's belt and the Orion nebula.

Hanging out with Astronauts: ESA/DLR's SocialSpace Cologne, 22 September 2013

(note: click the images with this post to get larger versions)

It can be safely said that unless you work in the space industry, you won't meet an astronaut very often. So you can perhaps imagine how exciting it is to the average space buff like me, to meet seven of them in one day!

Now hold that thought, and imagine how surreal the moment becomes when an astronaut (Léopold Eyharts, pictured below) is sitting at your table, in the chair right next to you, casually discussing the merits of the Soyuz versus the Space Shuttle in the same way that others compare a Volkswagen to a Prius...

Astronaut Léopold Eyharts sitting next to me at SocialSpace Cologne, discussing the merits of Soyuz versus Shuttle

That certainly is not your average Sunday afternoon....

The scene I describe happened in the afternoon of  Sunday 22 September at the SocialSpace Cologne meeting organized by the European Space Agency ESA and the German Aerospace organisation DLR.  The meeting took place at the DLR complex near Cologne, Germany.

SocialSpace is ESA's new name for a Space Tweetup, the new name reflecting that they seek an audience from a wider scope of their social media followers than just Twitter.

Until a year ago, when I attended my first, the 'tweetup' phenomena was completely unknown to me. Readers of my report on the May 2012 AndréTweetup at ESTEC will remember how I was unsure what to expect, half of me fearing that I would be confronted with 70 Sheldon Coopers plus a handful of Wolowitzes, dressed up in trekkie costumes...

(incidentally, there was a trekkie among the SocialSpace attendants this time, dressed up as Mrs Spock. Yes, Mrs Spock...: in stockings, and complete with pointy ears).

In reality, these tweetups turn out to be interesting and fun, the people involved generally quite sane and very nice, and an occasion where you make new friends. Some of these I now met again, in the context of this SocialSpace Cologne event, and I discovered that this proces of meeting attendants you know from a previous tweetup, together with the fact that you make a bunch of new like-minded acquaintances, is an important part of the social process of this kind of meetings. For example, I met Eico and Alex Neumann again (@Travelholic and @4tuneQkie on Twitter), even though they did not participate in the actual tweetup SocialSpace this time. They were however present at the informal social gathering at Brauhaus Sion the evening before the event.

SpaceKoelschX the evening before SocialSpace: 40 Space tweeps, beer and schnitzels

This unofficial pre-gathering called SpaceKoelschX consisted of some 40 people gathering for Kölsch (local beer), schnitzel, bratwurst, bratkartoffeln and a general swell time on the evening before the SocialSpace event. Most of them were SocialSpace attendants, and some of the ESA social media people were there as well. But the group also included people from previous tweetups that were not selected to attend this time, but came to Cologne on their own volition to visit the German Aerospace Day, a huge event which attracts about 100 000 visitors.

The ESA/DLR SocialSpace event itself took place the next day in a large tent on the vast DLR grounds bordering the airfield near Cologne, in the context of the already mentioned bi-annual German Aerospace Day.

two fish-eye views into the SocialSpace tent

The 60 attendants were selected from a large group of active social media followers who applied to a call spread through the ESA/DLR social media accounts (i.e., Twitter and Facebook). These lucky ones selected, including yours truely, got treated to a special program of lectures, a VIP tour through the DLR and ESA facilities, as well as a meet-and-greet with a whole bunch of astronauts.

And when I say "a whole bunch", I truely mean: a whole bunch. At a certain moment our SocialSpace tent on the DLR grounds started to teem with blue flight suits, to the point where I started to mutter: "we must find the nest and destroy the eggs!".

The image below shows you, from left to right: Reinhold Ewald, Thomas Pesquet, André Kuipers, Alexander Gerst, Frank de Winne, Léopold Eyharts and Andreas Mogensen:

Part of the tweetup SocialSpace tradition seems to be the presence of a number of mascots. I have covered Hugh the bear before in my report on a previous tweetup: present this time were a host of other mascottes, ranging from a Space Barbie to a Pink Little Dragon to Camilla the Space chicken. I must admit, this is a part of the Space tweetup SocialSpace folklore that I still have to get used to...

Me posing with Pink Little Dragon and Camilla the Space chicken

@projmgr and Space Barbie

@4tuneQkie with Camilla the Space Chicken and Pink Little Dragon during the SpaceKoelschX

ESA's Daniel Scuka (right) and another ESA employee who's name I do not know DLR's Elke Heinemann with Paxi, ESA's kids mascott. A life-sized version of Paxi visited us later.

While this all might make an impression of Space oddities, there was serious business as well. We got treated to a fine series of lectures that day by several ESA and DLR scientists, astronauts and a test pilot.

After we were picked up at Porz-Wahn station and brought to the venue by bus, the traditional handing out of badges, T-shirts and goody bags took place. After brief general introductions by the organizing team of ESA and DLR, we all shortly introduced ourselves. One of the nice things of large ESA tweetups like this is the very international vibe. The attendants to this SocialSpace came from all over Europe and even beyond, including the US and Canada.

Next we all set up shop with our laptops and other devices, from which we started to Live tweet the event. After all, it is a tweetup, n'est ce pas? We did it so well that #SocialSpace became a trending topic for a while. Two of the attendants even established a live webcast of the event.

The series of lectures started with ESA's Robert Meissner lecturing about the use of satellites for remote sensing. Apart from breathtaking satellite imagery, his lecture provided a good overview of the kind of remote sensing observations satellites can perform, and their practical application. Keeping an eye on crop production and soil and biomass degradation are important applications, for example.

Apart from modern imagery and their application, Meissner also showed us the very grainy first image of earth ever taken by a satellite, over 50 years ago. With a jump to the future, he announced that the GMES/Copernicus data, an ambitious Remote Sensing program by ESA, will be Open Access.

Sometimes satellite images contain baffling things. In the image above, Meissner shows us a giant geoglyph of the Egyptian god Horus that is visible on satellite images of an area in the interior of Australia. It was probably created as a joke by the Oz Army Corps.

The next lecture by Jens Danzeglocke connected to the previous lecture by taking a detailed look at the role European spacecraft (amongst others) play in disaster crisis management. The information exchange network the spacecraft play a role in, helps local authorities to quickly assess damage from natural disasters and coordinate disaster relief efforts based on these results. Most of these activities (about half of them) concern flood disasters, and Danzeglocke told us that radar satellites play an important role in these, as flooding disasters tend to be accompanied by cloud cover. The international Space charter the European space agencies take part in covered over 400 disasters in 110 countries since  2000.

Next another Jens, biologist Jens Hauslagen, lectured about "food in space". This was an interesting lecture about research into the useful application of waste recycling for crop growing in a closed system (e.g. a Space Station). Did you know that one human produces 10 kg of urea, 110 kg of 'organic waste' (that is: poo) and 100 kg of left-over food each year? In a closed system, these have to be recycled, and Hauslagen works on a series of very intricate ways to do this, including all kinds of filters but also small bio-organisms and even fish. Not only does this reduce waste: by recycling it enables the growth of food in long duration missions. His work has a down-to-earth application too: for example, there is a Maroccan town that recycles leftover waste from its fruit- and vegetable markets with techniques developed by Hauslagen and his team.

DLR test pilot Steffen Gemsa

The next speaker was DLR test pilot Steffen Gemsa. This is one of the pilots who took off in a research aircraft to fly into the volcanic ash cloud during the April 2010 Icelandic volcano crisis. Yes, you read that right: all over Europe aircraft were grounded, and this guy deliberately flew into the ash cloud. It's part of his job, that also includes testing aircraft under specific conditions, and conducting research flights with scientific equipment. It was an interesting lecture, as a result of which I learned the interesting bit of trivia that there are only five (5) test pilot schools worldwide.

Following Gemsa, Manuel Mezt and Holger Krag of ESA and DLR talked us up to date on all matters concerning Space Debris, ways to detect them and ways to mitigate the dangers of them. This included some results of simulations, and visualizations of all space debris in orbit around the Earth. Which is 93% of all objects currently in orbit.

Manuel Metz visualizing all object in orbit

Krag told us that every day some satellites are hit by (very) small particles of space debris smaller than 0.1 mm. The number of particles has dramatically grown over the past years due to a Chinese ASAT test in 2007 and a collision between an old Russian rocket booster and the Iridium 33 satellite in 2010. Krag made clear that if we continue this way, spaceflight will soon become impossible. Hence, measures are necessary to reduce the amount of space debris.

One way to reduce space debris is by making objects decay faster. This can be done for example by fitting spent rocket boosters and decommissioned satellites with solar sails. These sails increase drag, reducing on-orbit lifetimes.

 Krag: fitting satellites with solar sails after decommision will speed up their decay

Incidentally, Dutch astronaut (ehrm, pardon: European astronaut of Dutch origin) André Kuipers would later tell us about his experience with space debris too: during his stay on the ISS in 2012, they had to do two diversion manoeuvres plus a retreat into the Soyuz capsule because of close encounters with larger space debris.

After I asked a question in the discussion, Manuel Metz came over to me at the start of lunch, and told me he actually reads my blog. Wow!

Lunchtime also served as an hour off to freely roam the DLR grounds. Together with @Susivic I made a short visit to the airfield to see some of the aircraft there, including a Eurofighter:

Eurofighter, the jet our government did not buy

Incidentally, this was also the moment we first glimpsed André Kuipers, whom would later visit us in the tent.

When we came back from our short stroll over the DLR Open Day, DLR chairman and ESA director Jan Wörner and Thomas Reiter briefly took the stage.Whenever you see suits on stage, you know they will talk politics. Space politics in this case, with a brief discussion of future plans and goals. Reiter made the interesting statement that "I can believe we will perhaps see humans return to the surface of the moon in the next decade".

Next came a series of lectures all connected to ESA's Rosetta sampling mission to comet Churyumov-Gerasimenko. The first lecture, a grand overview of this exciting mission to land on a comet (!), was by project PI Gerhard Schwehm, who was involved when the mission was conceived in 1985 (!) and now will see it completed just before his retirement. In the original plans comet Wirtanen was the target, but when the launch suffered a  delay, comet Churyumov-Gerasimenko was selected.

 Schwehm

After Schwehm, and as an intermezzo, the astronaut and my fellow countryman André Kuipers took the stage, as a replacement for Samantha Cristoforetti who at the last minute could not make it.

I decided that the Geek code in this case as a rare exception does allow for a selfie:

Selfie with astronaut in the background

André told various anecdotes from his PromISSe mission in 2012 (the longest ESA mission onboard the ISS), including the short-circuit in the solar panels, the temporary retreat into the Soyuz because of a dangerously close encounter with a large piece of space debris, and the fact that all three of them threw up after their Soyuz capsule landed in the Kazachstan steppe. He told us astronauts need half a year to recover from a spaceflight and that the bone loss suffered during a long ISS stay might actually never fully recover. The unknown long-term effects of cosmic radiation are also a concern.

Kuipers stated he welcomes commercial spaceflight as long as it is done safely, and he said he believes the SpaceX Dragon will one day fly astronauts.

Kuipers was one of the two astronauts grappling and hooking up the first DragonX capsule to the ISS. Later that day, when the astronauts present intermingled with the SocialSpace attendants, he would tell the story of docking the Dragon in more detail:

St Kuipers, retelling how he slew the SpaceX Dragon in an epic heavenly battle

Stephan Ulamec and Koen Geurts next lectured on details of the Philae lander that is part of the Rosetta mission effort. Ulamec told us that since no-one has ever landed on a comet before and we actually know very little of the make-up of the nucleus of the comet in terms of surface condition and density, it is a very tricky thing to do. Another challenge is the long-term operation of the spacecraft without RTG's to provide energy (Rosetta/Philae has solar panels only).

The lander is actually washmachine sized and the landing will involve a bit of Space Whaling: the probe will fire two harpoons into the cometary nucleaus and rope itself in. Its first act will then be to take a 360 degree panorama to see in what position it landed. Ulamec succinctly summed up the scientific importance of the project by stating: "If you want to get to the pristine material, you will have to land there" (with "there" being the comet, which is made up of pristine materials from the formation of our solar system).

After these highly interesting lectures, it was time for our VIP tour through the EAC facilities. We were divided up in two groups, each of which  was met by an astronaut (in my group's case, Thomas Pesquet) who would act as our guide. Pesquet did not spare us the gory details: at the Neutral Buoyancy Facility, he told us astronauts frequently lose a fingernail while practising in the suit in what I am apparently not allowed to characterize as a giant swimming pool.

Columbus module mock-up in the EAC Neutral Buoyancy Facility

Apart from the Neutral Buoyancy Facility, we also got a quick glance at the only existing life-size mock-up of the ATV, which made me realize how big the ATV's actually are. Next, Pesquet took us to a place rarely visited by outsiders: ESA's  Eurocom control room, where they monitor and control all kinds of European things going on in the International Space Station:

Eurocom

 Thomas Pesquet explaining things in the Eurocom control room to us

Geek humor in Eurocom

After this first truely Close Encounter with an alien astronaut, we went back to the SocialSpace tent where we got a very cool demonstration by ESA's  Advanced Concepts Team, who work on some very geeky stuff. They demonstrated a quadcopter drone controlled by an iPad app, simulating the ISS in a game environment. The app might one day actually help finetuning techniques so drones (or spacecraft) can automatically assess distance.

the drone

Then it was time for more astronauts again. Alexander Gerst who had elsewhere just completed a press conference where he revealed the name of his upcoming ISS mission, Blue Dot, and Thomas Pesquet who earlier was our guide at  the EAC tour, took the stage.

 Thomas Pesquet (left) and Alexander Gerst (right)

They turned out to be a golden comedy duo, with very witty retorts between the two. Thomas Pesquet next asked the audience for suggestions what to do in terms of social media activities when he is in the ISS, "since about everything already has been done by now...". May I suggest a weekly comedy show from space perhaps?

Then the moment came where the tent suddenly started to teem with an overload of astronauts. Seven of them took the stage, and next intermingled with us by sitting down among us at the tables, answering questions and relating experiences. At this point, we had a significant part of the European astronaut corps hanging out with us!

 Léopold Eyharts, who went to MIR in a Soyuz in1998 and to the ISS in a Space Shuttle in 2008, sat down next to me and told us the ride up is better on the Soyuz, but the journey down is much more comfortable on a Shuttle. One of the reasons which he mentioned for that verdict was the constant swinging of the Soyuz capsule under the parachute.

Apart from listening to Léopold Eyharts, I listened to André Kuipers and later had the opportunity (thanks to Suzanne Pieterse (@Susivic), who handled the camera) to have my picture taken with him. He also signed a folder of postcards for me and my SocialSpace badge. Which made me tweet, in a Sheldon Cooper moment: "Now I have his DNA!"

André Kuipers kindly posing with me

signed badge and postcard folder

With this, the day finally ended. Or more or less: there was an informal drink afterwards, which saw more opportunity to talk to astronauts, various ESA people and other attendants.

ESA's Social Media guy, Daniel Scuka, talking to two attendants

Around 18:45 I left for the station for the ICE journey back, but not after grabbing a quick bite with Lynn van Rooijen (@lynnvr) at the trainstation. I was knackered when I arrived home, well after midnight: but it had been worth it. This was a cool day with an overload of astronauts, a highly interesting lecture program, and lots of very nice people. I would not have wanted to miss it!

I warmly want to thank the ESA/DLR organizers, and specifically Daniel Scuka, for inviting me to this wonderful day and all the good care they took of us.


(Note: photographs with this report were taken with two cameras: my Canon, and a rather old and decidedly less quality iPhone. So apologies for the bad quality of some of them)

[UPDATED 2x] Visualizing the trajectory of the September 10 Trident missile test in the Atlantic

The past days I have covered the story about German astrophotographer Jan Hattenbach's September 10 strange photographic observations from La Palma on this blog. Along with Jonathan McDowell I quickly suspected this was a  missile test launched from a submarine in the Atlantic. This was later confirmed: Lockheed-Martin and the US Navy announced that it was a test with a Trident II D5 SLBM launched from a submerged Ohio-class submarine.

More information next emerged that contained some clues to the launch trajectory. Now Cees Bassa has done an extensive analysis, modelling a trajectory. The details can be found here on the Seesat-L mailing list. He finds a launch location near 28 N, 68 W, more to the west than I initially thought.

I used Cees' results on the launch location and STK to fit a ballistic trajectory through Cees' launch location and the probable target area discussed earlier. The trajectory (visualized below) fits well with the altitudes and azimuths as photographically observed by Jan Hattenbach from La Palma (see astrometry in the appendix to my post here).

click maps to enlarge

The trajectory STK fits allows to say something about altitudes and flight-times. The launch occurred near 21:10:40 UT. After a 36 minute flight over a distance of 8660 km, the target area between St. Helena and the Gabon/Congo coast was reached near 21:47:00 UT. In the top of its ballistic trajectory, the missile reached an altitude of 1800 1900 km.

(note added 27 Sep 2013, 13:00 UT : Cees Bassa has since released the detailed data of his ballistic curve fitting: he has the apogee somewhat lower, at 1650 km, and a flight time between 21:10:00 UT and 21:44:45 UT, one minute faster. Please note that the diagrams below are based on the STK derived trajectory I cobbled together, not Cees' data.

Update 28 sep 13:00 UT: Cees' trajectory does not have the impact point in the published exclusion zone, but somewhat to the East of it. That is the major cause of the discrepancy between the results Cees published, and the ballistic trajectory I present here, which does land squarely in the exclusion zone. With the impact point shifted slightly westwards, the apogee altitude shifts upward if one wants to match the azimuth/elevation data from La Palma.)

click diagrams to enlarge

The two events at 21:17:08 and 21:08:43 UT that I initially misidentified as the 2nd and 3rd stage ignitions, but which are, as Jonathan McDowell pointed out, likely the MIRV bus and MIRV separations, happened at 1130 and 1330 km altitude in the ascending phase, after 6.5 and 8 minutes of flight-time, 1860 respectively 2235 km from the launch location. They are marked in the diagram below:

click diagram to enlarge

(note: for this post I am much indebted to Cees Bassa and his fine analysis. His trajectory reconstruction provided the basis for the diagrams and the timing and altitude information in this post. Cees' own detailed trajectory data can be found here - they slightly differ from what I present above, but see the note elsewhere in the post above.)

More on the September 10 mid-Atlantic Trident SLBM test captured by astrophotographer Jan Hattenbach

On September 20 I blogged with an analysis of photo's taken from La Palma on September 10 near 21:18 UT by German astrophotographer Jan Hattenbach. The pictures showed a strange phenomena which was quickly suspected to be a SLBM test. A suspicion that was confirmed yesterday when Lockheed and the US Navy announced they indeed tested a Trident II D5 missile that day, launched from a submerged Ohio-class submarine in the Atlantic.

Since then, more discussions have ensued on the SeeSat-L mailing list. Chiming in were amongst others Ted Molczan, Jonathan McDowell, Allen Thomson and Cees Bassa. These discussions and new pieces of evidence provide a possible target area for the test, and if some of the things brought up are correct, indicate that the launch location, the trajectory and imaged part of the flight path might be somewhat different from my initial assessment (which as I noted was very rough and very approximate: there was a reason I didn't provide a detailed map)

First, Ted Molczan managed to dig up a Broadcast Warning to mariners for the south Atlantic (that I was not able to trace to a URL). The text:

( 090508Z SEP 2013 )
HYDROLANT 2203/2013 (57)  
(Cancelled by HYDROLANT 2203/2013)

SOUTH ATLANTIC.
ROCKETS.
1. HAZARDOUS OPERATIONS 091400Z TO 140130Z SEP
   IN AREA BOUND BY
   09-18S 000-26W, 09-50S 000-32E,
   12-03S 002-39E, 13-40S 004-09E,
   14-09S 003-49E, 13-06S 001-56E,
   11-05S 000-58W, 10-55S 001-05W,
   09-56S 000-50W.
2. CANCEL THIS MSG 140230Z SEP 13

Ted speculates that the area indicated is the target area of the (dummy) warheads from the Trident. Indeed, it is about 7000 km away, well within the ~11 000 km range of the Trident missile, from the general launch area I deduced earlier (but see below). It would mean my launch azimuth estimate was off by 40-45 degrees (and closer to 130 degrees). And it could very well be given that it was a very rough deduction from observations from only one location, with several assumptions involved. To reconstruct it properly, you need observations from two locations, so you can triangulate.

The potential target area is in the eastern part of the South Atlantic, between St. Helena and the coast of Gabon and Congo. It is elongated and the major axis of the polygon might be indicative of the launch direction. In that case, the missile trajectory was approximately as pictured below (Red line: missile trajectory. Yellow lines: sightlines from La Palma for the range I astrometrically measured (21:17:08 to 21:19:42 UT): this does not include the earliest part where it emerged from the horizon as seen from La Palma. The grey polygon is the potential target area mentioned in above Broadcast Warning).

click map to enlarge

Meanwhile, the actual launch location is a point of discussion as well. In my earlier analysis, I interpreted two distinct events in the  photographed trail as the moments the 2nd and 3rd stage of the missile kick in:

 Jonathan McDowell has a different suggestion: he thinks these moments represent the MIRV bus and MIRV (the warheads) separations. These happen at much higher altitudes than the rocket stage burns. It would mean the object(s) were at a much larger range from La Palma than I deduced from my earlier notion it were the 2nd and 3rd rocket stage burns. It would shift the launch location significantly more to the Northwest (see map above).

BREAKING: the September 10 La Palma event WAS a Trident missile test!

In an earlier post I analyzed a mysterious sighting by German astrophotographer Jan Hattenbach from La Palma on the Canary Islands on September 10.

Based on an analysis of his photographs, I concluded that what he serendipitously captured was most likely an unannounced SLBM (Submarine Launched Ballistic Missile) test in the mid-Atlantic, possibly a US or British Trident test.

News has just broken that the US Navy in cooperation with Lockheed-Martin indeed conducted a test with a modified Trident II D5 Submarine Launched Ballistic Missile in the mid-Atlantic on September 10 (and again on September 12). The Trident D5 missile was launched from a submerged Ohio-class submarine.

(Tip of the Hat to Brian Webb who first brought up the confirmation news today at the SeeSat-L list)

You don't get to meet an astronaut every day

This weekend I was invited to attend ESA's and DLR's #SocialSpace tweetup in Cologne, Germany, organised in the context of the German Aerospace Day.

I will post a more elaborate photo report of this very fine and interesting meeting later this week, but for the moment I want to show you the picture below: Dutch ESA astronaut André Kuipers, who went to space in 2004 and 2012, was so kind to pose with me for a picture.

click image to enlarge

[UPDATED: confirmed!] A clandestine launch in the Mid-Atlantic on Sep 10, captured by a German astrophotographer?

UPDATE 24 Sep 2013 18:00:
It has now been confirmed that this was a US Trident SLBM test launched from an Ohio-class submerged submarine! So I was right!
(note added 25 Sep 2013: a post with more info subsequently come to light and an update on the probable launch trajectory is available here)

click image to enlarge

In the evening of September 10, 2013, German astrophotographer Jan Hattenbach was taking images with an f2.8/24mm lens near the GranTeCa dome, at 2300 meter altitude at the Roque de los Muchachos observatory on La Palma in the Canary Islands. His camera was looking due west, out over the Atlantic Ocean, in the direction of Bootes and Virgo. The intention was to create a time lapse movie.

Between 21:16 and 21:20 UT, he captured something unexpected on his images. A strange fuzzy bright object moved over the images, spouting cloudy puffs. Above is a stack of the images: it shows the GranTeCa dome, star trails, a normal satellite (Kosmos 1410)...and the strange cloudy phenomena coming under an oblique angle from the horizon. Below is a short movie made from the images (5 second images with a 2 second interval). Note that it is a time-lapse that speeds up the event: the whole phenomena took about 2.5 minutes in real time:



Jan wrote about his strange observation on his own blog (in German) and posted his story on the AKM forum and on Twitter. Rainer Kresken forwarded it to the SeeSat-L mailinglist, and science writer/journalist Daniel Fischer tweeted to Jonathan McDowell and me whether we could explain the phenomena. Next, Jan was so kind to make his original imagery available to me.

Initially Jan reported that the images were taken near 21:23 UT (Sept 10, 2013). However, it turned out that his camera clock was off by several minutes. The event in reality happened earlier.

Luckily, a "normal" satellite is visible in the image sequence too, briefly flaring, and Cees Bassa and me could identify that satellite as Kosmos 1410 (82-096A). As the orbit of this object is known, astrometry I performed on the trail yielded the correct image times. Jan's camera clock was off by 6m 17s, as it turned out. The phenomena took place between 21:16 and 21:20 UT.

After seeing the images, my first thought was that this could be a fuel vent by a rocket booster in Earth orbit. The time and trajectory did however not match any known object, unclassified or classified.

Another option was a satellite launch. There were however no launches scheduled for this date (and this includes launches of classified objects, which you really cannot keep secret. They are publicly announced as it involves temporary restrictions to airspace down te launch trajectory, and a very visible rocket ascent from Vandenberg or Canaveral).

At that point, I started to suspect that it could perhaps be a hush-hush suborbital ballistic missile launch test, similar to the September 2, 2013, US-Israeli missile test in the Mediterranean. Harvard space historian Jonathan McDowell communicated a similar suspicion, noting that the particular part of the Atlantic has seen Poseidon SLBM tests in the past.

The thing is, that no such test was announced for this date. For example, I have found no NOTAM's  restricting airspace over parts of the Atlantic because of a missile launch. That does not mean it is not a missile test though. It just means that whoever did the test, doesn't want to acknowledge it and preferred no-one to know about it. The September 2, US-Israeli test in the Mediterranean was not announced either (it came to light because it was detected by a Russian Early Warning Radar).

If the event seen from La Palma was indeed a clandestine Medium Range Ballistic Missile test (such as I believe is the case), the primary suspects are the Unites States or Great Britain, who both operate the Trident Submarine Launched Ballistic Missile (SLBM); or the French, who operate the M45 and M51 SLBM.

Several points in the observation fit a SLBM test. The US/British Trident and the French M45/M51 are 3-stage missiles. In the stacked image and movie above, there are two sudden bursts of brightness in the trail, both accompanied by an expanding puffy cloud. I interpret these as the moments of jettison of the 1st stage and ignition of the 2nd stage (note: but see update here); and ejection of the 2nd stage and ignition of the 3rd stage. I have marked these moments, taking place at 21:17:08 and 21:18:43 UT (so with a 1m 35s separation), in below detail of the stacked image. The corresponding astrometric positions of these points are RA 205.061, Dec -3.950, and RA 211.366, Dec -6.153 degrees.

click to enlarge

Below are details from the single still images from those moments:

click image to enlarge

Below is a detail from a single frame just after what I interpret as the 3rd stage ignition, showing a bright fuzzy trail and expanding vapour clouds on both sides:

click image to enlarge

The duration of the event fits what is known of the Trident missile: from launch to 3rd stage ignition takes less than 2 minutes with the Trident. The 2nd stage ignites at about 70 km altitude, the 3rd at about 150km altitude.

A careful look at the stacked image shows that after what I interpret as the 3rd stage ignition, the trajectory clearly starts to deviate from the previous more or less straight line:

click image to enlarge

This is not an effect of lens distortion, as I will show below. It is a real deviation, that fits a missile launch. It shows unequivocally that the phenomena is not a fuel vent by a rocket booster in earth orbit. Such an object (moving in a Great Circle) would move in a straight line when positions are plotted in a Gnomonic projection. I did this for Jan's object: I astrometrically measured points on the trail and converted and plotted the measured RA/DEC in a gnomonic projection system. The same deviation that should not be there if this was an object in Earth orbit is visible in the RA/DEC data:

 

click diagram to enlarge

This makes very clear that Jan's object was not in orbit around the earth, but on a launch/ballistic trajectory. So we can definitely exclude a rocket booster orbiting the earth from a previous launch and venting fuel.

Just to support my previous argument further: here is what the trajectory in RA/DEC looks like for an object in an eccentric GTO orbit observed near perigee over a similar time span as Jan's object. The comparison object is the USA 40 rocket (1989-061D):

Assuming the La Palma event indeed was an unacknowledged Trident SLBM test by the USA or the British, the known specs of the Trident provide a (very) rough indication of where the launch took place.

As mentioned earlier, the 2nd stage of a Trident SLBM ignites at about 70 km altitude, the 3rd at about 150km altitude. As mentioned too above, I interpret two points in the trail to represent these moments. By measuring their astrometric position and calculating the corresponding azimuth and elevation in the sky, we can get a rough indication of distance and direction at these moments. I did this as a (please note) very rough back-of-the-envelope calculation. It suggests the launch took place near latitude 23-25N and a longitude several degrees West of  40 W. This is right in the middle of the Atlantic, at least 2000-3000 km from any coast in any direction. Again, that points to a Submarine launched missile. The launch azimuth is roughly 80-85 degrees, towards the African coast at a distance of over 3000 km. (note added 25 Sept: but see update here that somewhat changes the picture)

The USA was testing missile intercepts near Kwajalein in the Pacific that same September 10. It is however highly unlikely that the launch that Jan seems to have captured is directly related, for the simple reason that a Trident launched in the Mid-Atlantic does not have the necessary reach to get to Kwajalein.

It is a busy time with missile tests: after the September 2 test in the Mediterranean, the September 10 tests near Kwajalein, and this potential unacknowledged test captured by Jan Hattenbach that same date, there was also a missile test in New Mexico on September 13. The Kwajalein tests were scheduled well before, but the unannounced September 2 test in the Mediterranean and perhaps also this unacknowledged September 10 test in the Atlantic might be part of ad hoc military practise exercises in connection to the continuing situation with Syria.

One question some might raise: why a Medium range Ballistic Missile launch? Why can't this not be an unacknowledged launch into Earth orbit? First: it would not be possible to keep such a launch from a US landbased site a secret. It would be seen over a wide area (like the New Mexico test) and necessitate temporary closure of parts of airspace. Moreover, altitudes and directions really point to a launch in the Mid-Atlantic. The only way to launch into Earth Orbit over the Mid Atlantic would be by an airborne launch using a Pegasus rocket.

All in all, and given the context of the situation in Syria and the September 2 test in the Mediterranean as well, it is much more likely that this is an unacknowledged SLBM test, launched from a US, British or French submarine in the Mid-Atlantic.


UPDATE 24 Sep 2013 18:00:
It has now been confirmed that this was a US Trident SLBM test launched from an Ohio-class submerged submarine! So I was right! 

Update 25 Sep 2013: New post with new info here, including re-assessment of the launch trajectory

(note: I thank Jan Hattenbach for making available his original imagery and for his permission to use it on this blog. And I thank Cees Bassa, Jonathan McDowell, Rainer Kresken and Daniel Fischer for discussions. Conclusions and any errors are solely mine).


APPENDIX  - added 24 Sept 2013, 19:50

Below are the astrometric data I used in my analysis. I did not measure every image, but enough to describe the track of the object. Measurements were done with AstroRecord astrometric software. Only the start of each trail segment was measured, except for IMG_1848 where the point where it brightens (3rd stage ignition) was measured as well. The observing site is at 28.7564 N, 17.8889 W and 2300 meter altitude. Times are accurate to ~1 second.



IMG       UT        RA        DEC
1835      21:17:08  205.061  -3.950
1838      21:17:29  206.335  -4.418 
1840      21:17:43  207.272  -4.737 
1843      21:18:04  208.731  -5.228 
1846      21:18:25  210.137  -5.743 
1848      21:18:39  211.071  -6.089 
1848_ign? 21:18:43  211.366  -6.153 
1850      21:18:53  212.081  -6.416 
1852      21:19:07  213.008  -6.790
1853      21:19:14  213.489  -6.977 
1855      21:19:28  214.450  -7.388 
1856      21:19:35  214.907  -7.585  
1857      21:19:42  215.493  -7.786