Geoff FordenCongratulations Iran!


“Kavoshgar” Launch Site shown in yellow; Satellite and rocket body shown in white

There will be plenty of time to discuss the security implications of Iran’s Omid satellite but for right now, let’s take a minute to appreciate the technological feat it represents! In the face of world opposition and sanctions, Iran has joined a very exclusive club: those countries that have managed to orbit a satellite. NASA has posted the first orbital elements of the satellite and its third stage rocket body and, running the orbits backwards, they are totally consistent with a launch from the “Kavoshgar” launch site at 18:38 on 2 February 2009 (GMT). Both the satellite and the rocket body come together and pass over the launch site at that time. The objects both have inclinations of about 55 degrees which is consistent with a launch toward the South East, which does not fully take advantage of the rotation of the Earth and was presumably chosen for range safety issues. (Sorry, a previous version of this post was somewhat confused on this point due to my wanting to get it posted as soon as possible!) The objects ended up in orbits with apogees of 322 km and perigees of 242 km. The orbital period of 90 minutes implies an orbit that is slightly lower than the Iranian statement of 14 orbits per day but not troublingly so. (My guess is that Iran must have had sufficient telemetry to do a preliminary orbital analysis at the time of the satellite separation though the satellite would certainly have been visible from Iran after its first orbit.)

The two stages to the Safir launcher that are visible in the pre-launch photos would not, I believe, get a satellite into orbit. The most likely explanation is a solid-propellant third stage inside the clam shell nose faring. What would be helpful is if somebody (amateurs?) watched the brightness of the rocket body (once that is definitively identified) to see if we can get some indication of its size from that. There should definitely be a considerable size difference between Safir second stage (which is about 5 m long and 1.25 meters in diameter) and a hypothesized third stage inside the clamshell.

Update: Amateur satellite observers in the UK have have used the radio signals from 2009-004A to determine it is the satellite. Optical observations seem to indicate that the rocket body is considerably brighter (mag. 4.5) than the satellite (which varies between 5 and 7). This would seem to favor the two stage hypothesis: Iran has probably developed a more powerful fuel/engine combination for the second stage! Now we can start being concerned about the security implications.

Comments

  1. FSB

    Geoff,
    thank you for the tone of your post — it is a refreshing change from the fear-mongering that will surely ensue in the comments here and elsewhere. (OMG, what if Iranians make it to the moon or Mars??)

    Hearty congratulations are due to the Iranian scientists and engineers who achieved this feat.

  2. Allen Thomson (History)

    Orbital elements for the satellite and rocket upper stage (I don’t know which is which) are available on the authorized-for-distribution site

    http://celestrak.com/NORAD/elements/tle-new.txt :

    2009-004A
    1 33506U 09004A 09034.19387999 .00095226 13865-4 25133-3 0 80
    2 33506 55.5083 313.4501 0099270 151.1927 209.4657 15.86589494 74

    2009-004B
    1 33507U 09004B 09034.19673867 .00095923 13300-4 31019-3 0 92
    2 33507 55.5529 313.4400 0144903 154.1368 206.6998 15.75803087 65

  3. Mehdi

    You may find some clues in the 3D Animation of the Launch

  4. Victor (History)

    Is there any indication of what this thing does? Seems a shame to go to all the time and effort and expense to shoot up a satellite without equipping it with radar, or cameras or at least an antenna of some kind.

  5. Geoff Forden (History)

    Jeffrey has posted an image of the satellite in the comments section of his posting that shows little antennas mounted on the satellite. I’m not an expert on antennas but given their size I would guess they radiate in the gigahertz range, perhaps high UHF to L band.

  6. Jeffrey Lewis (History)

    Here you go:

  7. mim (History)

    wow! really useful information Geoferry! enjoyed to read em and learnin something;
    so they did it; great! 😐

    ty

  8. wise

    The Faris text in ISNA clearly states that Omid is a small sattelite wich after broadcasting a message of friendship from the Iranina President is collecting data and transmitting it back to earth on two frequencies. It also states that receives guidance data from earth based stations. It states that it has eight antenas onboard.

  9. Ataune (History)

    There is a page in Iran Space Agency site

    !http://www.isa.ir/components1.php?rQV==wHQxAkOklUZnFWdn5WYMJXZ0VWbhJXYw9lZ8BkN4EDQ6QWStVGdp9lZ8BUM4ATMApDZJ52bpR3Yh9lZ!

    which gives some spec. for the satellite Omid.

    Satellite type: telecom
    Closed Dimensions: 40*40*40 cm
    Frequency band: UHF
    Heat control: passive

    (Sorry for the hyperlink format, I couldn’t find any way to make the long link fit in there)

  10. Pedro

    The trajectory seems to be pretty round; would this speak for a free flight phase?

  11. steph (History)

    Hi! Any info about the link between this satellite and the Aerospace Industries Organisation? Look at this news in brief by the Iran Daily (2nd February 2009):

    Satellite Ready for Launch

    Jump in Inventions

    Head of Iran’s Aerospace Organizations Reza Taqipour said on Sunday that the Mesbah Satellite is ready for launch.
    “Mesbah is a research and technical satellite that will gather information from some parts of the world and relay it to Earth. This type of satellite is called store and forward. The satellite was built jointly by experts from Iran’s Communications Research Center and Iran’s Scientific and Industrial Research Organization as well as participation of a foreign country. Various tests were conducted before it was declared ready for launch,“ he told Mehr News Agency.
    Since Mesbah is among the first satellites that was designed locally and built with foreign collaboration, it marks a lofty step toward acquiring modern aerospace technology, he noted.
    The official noted that the satellite will be unveiled at the Kharazmi International Festival as a major project, and expressed hope that with the experience gained in this project the country will move forward with more confidence in the future.
    Meanwhile, President Mahmoud Ahmadinejad also on Sunday said that in the Third Five-Year Economic Development Plan (2000-05) a total of 5,000 inventions were registered in the country.
    “However, thanks to the diligent efforts of our youth that number increased to 25,000 inventions during the Fourth Development Plan (2005-10). So far in 2008-09 alone about 10,000 inventions have been registered,“ the president said
    while addressing the National Festival of Innovation and Prosperity underway at Tehran’s Prayer Grounds, Fars News Agency reported.

  12. Geoff Forden (History)

    Just to keep everybody informed, there is quite a discussion going on right now off-line about the animation that Mehdi linked to above. This animation, if taken at face value, definitely shows a two stage rocket putting the satellite into orbit. Some have pointed to the R-12 as a possible analogy. However, the R-12’s second stage has an Isp (specific impulse, a measure of how powerful the fuel/engine is) of 352 s, much greater than SCUD-type technology—even with gimbaled nozzles—could possibly give. So the question is, is there a third stage hidden in the nosecone faring (and why would they do that?) or has Iran made considerable strides in developing a more powerful engine/fuel? Im hoping that the amateur satellite observers might help answer this by looking at the relative brightness of the two objects Iran has orbited. Otherwise, I remain skeptical of such a major advance by Iran; but, heck, Ive been wrong before, right?

  13. Allen Thomson (History)

    Frequency:

    HearSat participants in Europe are reporting reception close to 465 MHz in a pass a few minutes ago.

    http://www.svengrahn.pp.se/trackind/OMID/OMID_signals.htm

  14. gpc (History)

    this is a momentous event being downplayed by the Israelis

  15. de Peche

    Oh yes…let’s all put our head in the sand for science and get giddy over the ayatollahs having an orbital launch platform for their soon-to-be nukes. brilliant

  16. Pedro

    @Geoff Forden

    The official line is that its a two stage SLV, also shown in the animation.

  17. Geoff Forden (History)

    Let’s not forget that John Glenn congratulated the Soviet’s on putting a man into space before the US did. This event does have important security considerations but peaceful exploration of space is a right of all humankind. The peaceful applications should be applauded.

  18. Amir (History)

    Geoff,

    How can I predict observation times for my location (Calgary, AB, CA). If I have the observation times, I will try to take some photos (hopefully, from light polluted city) so we can estimate the brightness magnitude. I checked heavens-above.com but they don’t have the satellite in their database yet.

  19. Jochen Schischka (History)

    I must side with Geoff on this one – it’s really hard to believe that this type of missile is capable of generating enough delta-v for that kind of orbit in a two-stage configuration (even if you assume a R-27-vernier-engine with radiation-cooled nozzle extensions for the upper stage as i suggested some time ago).

    On the other hand, i can’t exclude this possibility with absolute certainty either, but that means the missile structure (especially of the upper stage) has to be more lightweight than previously thought. Or maybe the Iranians bought some small vacuum-optimized closed-cycle engine from the Russians (there is no icing on the missile visible, so cryogenic propellants can be excluded)…

  20. Geoff Forden (History)

    For those interested in observing the satellite, they can go to
    http://www.n2yo.com/?s=33506
    to see where it is. There is also a button on that page to make predictions for when it will pass over your position. This will certainly be fun, and bring a certain nostalgia for the 1950s and sputnik, but the amateur observers, who have had experience in this sort of thing, are already making these observations. I will report back as more information becomes available.

    (ps Im really not trying to discourage you!)

  21. Geoff Forden (History)

    on one further note, the velocity differences between the rocket body and the satellite were about 15 m/s at separation. That could probably be achieved with several large springs. So the altitude differences are not done on purpose.

  22. mim (History)

    here is some information I found about the engine stuff! I’m not advanced on it at all! but just thought if it help:
    http://tinyurl.com/omidsat
    🙂

  23. Jochen Schischka (History)

    After some reflection on this issue, i must say that i’m also somewhat sceptical on a third stage hidden under the shroud – from what i’ve seen in the publicized footage so far, the payload shroud was not larger than on the previous Safir, only about 1.5-2m long; the missile’s guidance system will take up another ~0.85m of that length and the satellite itself (if the device from the Ahmedinejad-presentation was really the object launched) another 0.4m. This leaves only about 0.25-0.75m room for an additional stage (and i haven’t taken an adapter-ring for the payload and neither the curvature of the shroud nor its thickness into account).

    Some thoughts on the satellite itself: if the presented 40cm-cube really is identical with the on-orbit device (like the YouTube-animation suggests – Thanks, Mehdi!), then it obviously lacks a solar generator (aka has only a battery as energy-source and thus a rather limited life-time) and i can also see no signs of any form of attitude control system. Thermal insulation will probably be accomplished by glass-fiber fabric; BTW, there are no mounting points for small rocket boosters on the sides of the 40cm-cube visible, and there is obviously no space for that inside of it…

    Has anybody checked yet if the orbits of Omid and the ISS overlap at some point (although the probability of a collision would, of course, be only extremely small – just imagine the international political fallout of such an incident!)?

  24. Jochen Schischka (History)

    Oh, and Geoff:

    I think you were referring to the Kosmos-B1 in one of your earlier comments, since the R-12 is a single stage-missile (and the Kosmos’ first stage is actually a modified R-12).

  25. Azr@el (History)

    It seems a safe bet to go with the working theory that the official is line is correct; two stage SLV. Now this begs the question…what would the ceiling be on a 3 stage version? The Omid is a 20kg satellite, the Mesbah is a 65kg satellite, could the current carrier accommodate the launch of the Mesbah…or would a third stage be required? If a third stage is introduced would the Mesbah’s 65 kilos be the upper limit of it’s ability or would there be a higher payload ability to LEO and by extension a higher throw weight for the carrier if used for more mundane purposes.

  26. wise

    In the Farsi article published by ISNA it states that this is a two stage rocket. The president of Iran also talks about a two stage rocket in his speech. They also talk about 3 month life span for this device before it reenters.

  27. Andy (History)

    First of all, Iran has earned an important “first” as the first Islamic nation to successfully orbit a satellite.

    Secondly, unless I’ve missed something (quite possible as missiles are my field of expertise), I don’t see any compelling evidence to support the theory that this was a 3-stage missile although that’s still a possibility. It might be useful, however, to make the assumption that it is a 2-stage SLV, and work backwards from what we know to come up with some possibilities explaining how Iran might have done it with only two stages.

  28. Geoff Forden (History)

    I guess I need to go into this in somewhat more detail. What ever Iran used to put the satellite in orbit, it needed to achieve a speed of 7.8 km/s at 242 km altitude. I find that very hard to accomplish with the fuels I think the Safir used (nitric acid and kerosene). When I try modeling it, I get a two stage Safir giving a 25 kg satellite a speed of 6.4 km/s at 200 km. David Wright quotes a considerably smaller velocity, though I dont understand his model; it seems to be some sort of Taepodong variant. (I could be wrong about that, but thats what I get from his comment in Jeffrey’s post.) Given these calculations, it seems to me and others that two stages seems improbable unless Iran has achieved a considerable advance in engine/fuel specific impulse. On the other hand, the initial brightness measurements from experienced amateur satellite observers seems to favor a final stage that is considerably brighter than the satellite. That in turn favors the two stage model which implies Iran has made a considerable advance in technology.

  29. Geoff Forden (History)

    Oh, I guess I should also say that I don’t necessary believe what Iran says or what they show on their animations. I’d much rather see it for myself.

  30. Andy (History)

    Geoff,

    I understand what you’re saying, but from my perspective, there’s nothing definitive (as in demonstrable evidence) that points toward more than two stages. I understand what your model is saying, but I’m one that’s skeptical enough on models that I don’t readily substitute what they predict for evidence.

    But let’s assume for a minute there were three stages – why would Iran say there were only two? What purpose does that deception serve, especially since the Iranians must know they would not be fooling anyone and the truth would come out eventually?

    I guess what I’m getting at is that maybe it’s time to check some assumptions and look at the problem backwards. Start with the assumption that it was a 2-stage vehicle and use the hard data we have from the launch and work backward to attempt to figure out reasonable assumptions to explain what we know and see where that leads.

  31. Amir (History)

    Geoff,
    Thanks for the link. I don’t think observing them would be very difficult if they are brighter than 6-7. (I am an amateur astronomer, however, not specialized in satellite observation and just have done it few dozen times)
    I am going out to photograph the satellite (and the second stage probably) tonight. Hopefully, sky clears by that time!
    Can you mention the brightness magnitude of the satellite and the second stage? And how much different are the orbits of the Omid satellite and the second stage (in minutes for observation)?

  32. Curious Citizen

    Geoff,

    What happens to your model if you use a different kind of fuel?

  33. azr@l

    anyone knows why is that a cube? and not sphere for instance;
    and why it have alot antennas in all sides? is it coz it can’t be stabilized so?!

  34. Paul

    Higher resolution photos

    Photo 1

    Photo 2

    Photo 3

    Photo 4

    Photo 5

  35. Paul

    Three good quality videos – right click and save to disk.

    Video 1

    Video 2

    Video 3

  36. Mark Konrad (History)

    Dr Forden,

    Permit me to second the comments made by FSB — Thank You for the tone of your post. And permit me to second your comments — Congratulations Iran !

  37. Sadegh (History)

    The picture in following link shows that Safir has just 2 stage.

    http://www.abdolian.com/thoughts/wp-content/uploads/2008/Omid-Rocket/Ahmadi-Omid.jpg

  38. Azr@el (History)

    7.8km/s ? That can’t be right, air drag and gravity drag should add another 1.5-2.6 km/s to the delta-vee budget.

    As far as the fuel/ox choice…it seems like they’re probably using N2O4 for the oxidizer. For fuel I wouldn’t be surprised if they’re burning UDMH or if they’re crazy enough; hydrazine. More than enough ISP for a two stage to orbit carrier rocket.

  39. Raghar (History)

    What they used as a first stage?

  40. Markus Schiller (History)

    Details of the launcher and the satellite:

    http://youtube.com/watch?v=M8oOOmBIlCA

  41. Hamed (History)

    Thanks for your post,Excellent infomation and your friendly tone.

    And by the way we can also make it to the Moon or Mars.It is just the matter of time and money 😀

    Thanks

  42. Hamed

    Just listen to her voice…Unbelievable!!

    http://en.wikipedia.org/wiki/File:Omid-telemetry.ogg

  43. Reza

    How did you make that audio recording?

  44. Jim Oberg (History)

    Iran has noticed the discussions here!

    NASA Admits Successful Launching Of Omid Satellite
    Tehran IRNA in English 1545 GMT 04 Feb 09
    Tehran, Feb 3, IRNA – The US space agency NASA has admitted successful sending of national Omid (Hope) Satellite into the orbit on Tuesday.
    Geoffrey Forden, research associate at the Massachusetts Institute of Technology writes, “In the face of world opposition and sanctions, Iran has joined a very exclusive club: those countries that have managed to orbit a satellite.” Based on data released by NASA and reports from amateur observers, Forden wrote on armscontrolwonk.com that it appeared the satellite was successfully sent into a relatively low orbit.
    But it remained unclear if Iran had used a three-stage rocket with technology associated with Soviet-era Scud missiles, or had made a “quantum leap” with a much more powerful two-stage rocket, he said. “If it was a two-stage missile then they had a huge jump in technology and that would be very scary,” Forden added.
    The sophisticated two-stage rocket “would certainly advance the possibility of an ICBM much more than we’ve been thinking about until now.”
    He said there were indications from amateur observers of the launch that the Iranians had used a two-stage rocket, but it was too soon to reach any conclusions

  45. pedram (History)

    Geoff:

    From the tracking website you gave in an earlier post, Omid seems to be deviating west-ward from its initial orbit.

    In fact, it goes over saudi arabia now instead of Iran.

    Any hint here? Can it be on-purpose? Or the website is wrong?

  46. Geoff Forden (History)

    Pedram, the orbit appears to move across the Earth’s surface because the Earth is actually rotating beneath it. In fact, this satellite never really repeats the same orbit twice. My image of the orbit in this post is therefore somewhat misleading since it shows the orbit in what is known as the “inertial frame” and Earth as fixed. If I could show you the full simulation, you would see the Earth move.

  47. Pedro

    Can any hobby astronomer tell us whether the 250-380km orbit of the Omid is a elliptical one, reachable by a continuous burning upper stage or if it can be counted as circular and thus only reachable with a free-flight phase of the upper stage?
    An answer could tell much about the complexity of the guidance technology used, as well as important information about the upper stage design. From outside it looks like that it is a re-ignitable design and if that’s the case, it would be quite interesting from the military standpoint.

  48. ataune (History)

    @Pedro

    From the head of Iran Space Agency Press Conference yesterday:

    Omid is in an elliptical orbite with an apogee of 500 km and perigee of 250 km.

    Safir 2 is a 26000 kg launcher rocket, with 22 m length and 1.25 m radius.

  49. Tal Inbar

    Life span of the Omid – It will be interesting to see for how long the satellite will be operational without solar panels. I assume the batteries are Lithium/polymer.

  50. pedram (History)

    They said 2-3 months.

    After which it is either left as space junk or fall in atmosphere and burns.

  51. ataune (History)

    Life span is expected to be 2 months. According to the head of ISA, this is the “Achilles heel” of the experimental project.

  52. Azr@el (History)

    The pictures are amazing but they raise a couple of questions. It seems the tankage of the first stage is about 3 and a half times that of the upper stage. So why are they using different fueling/OX probes for the upper and lower stage? If the fuel/OX is not cryogenic and the volume difference is only a multiple of three plus…why go to the bother of making two different types of fueling probes? Wouldn’t one configuration suffice and have lower RD cost?

    Secondly it seems that this design is more than just horizontally integrated…it appears to be roadable via a tel.

  53. mhrd

    dear pedro,
    orbital shape can be defined by a parameter which called orbital eccentricity. this parameter expresses if a trajectory is circular, elliptical or parabolical. Commonly when the eccentricity of an object is less than 0.01, we assume the orbit circular and when it is betwean .001 up to 1 it is elliptical. In the Omid case, the eccentricity based on the data we have now(Rp=6378+250,Ra=6378+380) is about 0.0097, so we can tell it is flying in an near circular orbit.
    you can calculate the eccentricity by simple formula below:
    Ecc=1-2/((Ra/Rp)+1)
    where Ra is the apoapsis radiuos and Rp is periapsis radious.

  54. Amir (History)

    Before the launch they mentioned it will be in orbit 1-3 months and then it returns to the Earth. The way it was mentioned it sounded like it will be a planned reentry and satellite will be captured (I don’t see how they can do it).

    It is mentioned in the spaceweather.com that there is enough orbital info to calculate the satellite’s decay rate and they predict the satellite and the final stage of Safir-2 should reenter Earth’s atmosphere in June-July 2009.

  55. KHX
  56. Allen Thomson (History)

    > fall in atmosphere and burns

    Initial estimate of the reentry of Omid is mid-June this year, with the Safir upper stage following in late July. Both are currently uncertain by about a month.

    http://www.satobs.org/seesat/Feb-2009/0076.html

  57. Mohammad

    If you know Persian (Farsi), you can find almost complete information on both the launcher and the satellite (and also the project) here.

  58. Mohammad

    There’s also an almost detailed description of Safir here, which clearly says that Safir is a three-stage rocket (It doesn’t mention its source).
    That forum topic has gathered some information that may be of interest to any one who wants to know more. But it is in Persian.

  59. Jochen Schischka (History)

    Azr@el:

    If the actual upper stage engine on the Safir really is the engine from the presentation last year, then it is highly likely that it’s a modified two-chamber-vernier-engine from the russian R-27/SSN-6/Serb using IRFNA or NTO as oxidiser and UDMH as fuel. The first stage engine, from what i’ve seen, is with high likelihood a NoDong-engine burning AK-27I-IRFNA/TM-185-Kerosene (ignited by TG-02-Tonka). But since i see some discrepancies considering sea-level-thrust of the NoDong-engine, liftoff-weight of the Safir and the liftoff-acceleration, maybe this engine has been tinkered-with to achieve higher chamber-pressure (70 bar instead of 55 bar?) and thus a higher thrust level (the Ghadr-1/NoDong-B could also profit from this effort). Has anybody information pointing in that direction?

    And, at least for now, forget about road-mobility (technically speaking it’s a MEL, not a TEL), since the upper stage obviously is fueled in upright position from the fixed service-tower (has anybody else noticed the piping and the aerating hoses on the tower?); I don’t know if a) the hydraulics of the MEL would be strong enough to erect a fully fueled missile of such a great length and b) if the missile itself would not break up under the additional load (as i wrote in an earlier comment, according to the laws of physics, this missile has to be rather fragile to be capable of the demonstrated performance).

    Oh, and the employ of up to five different kinds of fuel (1st stage: IRFNA + Kerosene + Tonka, second stage: IRFNA/NTO + UDMH) alone would ensure this 22 meters long missile to be a show-stopping nightmare for any kind of credible road-mobile military operations…

  60. RKelly (History)

    Arms Control Wonk.com – You can’t be serious. It’s like sending Russia a thank you note for JOE 1.

  61. Omid (History)

    Dear Mohammad
    I wrote that article on military.ir and my source about the third stage was the article in Aerospace Industries Organization monthly magazine.But it seems Omid didn’t need the third stage to go into the orbit.

  62. B. Berger (History)

    I simply don’t believe in the two stage approach. If it’s the second stage you can see behind the Omid in orbit, it would mean that they orbited the 20kg Omid AND a several hundred kg empty second stage. And this is very unlikely considering the medium performing propellants and technology. I am pretty sure they used a small (solid) kick stage attached to the satellite (and this is what you see in Orbit behind the satellite). Kick stages are often considered as a part of the satellite and are therefore not counted as stages of the launcher.

    Has anybody an idea what range the rocket would have if used as a missile?

    Nevertheless, this is a great achievement and I have respect for this!

  63. Payam (History)

    That one also says 2-stage in fuel process Mohamad.

  64. Jochen Schischka (History)

    To RKelly:

    I think this is more like thanking the Russians for delivering the Sputnik-shock; And for putting up two additional chunks of uncontrollable space debris running on elliptical orbits through some of the most densely populated areas of space…

  65. Jochen Schischka (History)

    To B. Berger:

    I can completely understand your doubts considering a two-stage approach (i have more or less the same problem with this missile). But IF (big if!) the launched object REALLY was the presented 40cm-cube, then there was obviously not enough room inside of the payload-shroud of the Safir-2 for such an additional kick-stage (like i demonstrated in an earlier comment). BTW, such apogee-engines usually are integrated into the satellite structure itself (clearly not the case with the 40cm-cube – see Paul’s videos) and thus don’t separate after burn-out (the apogee-engine approach would also have helped to avoid the bigger one of the two pieces of space debris, since this would have allowed the second stage of the launcher to remain slow enough for rapid deorbiting – but these kinds of considerations obviously don’t bother the Iranians).

    As for the possible range in a hypothetical surface-to-surface-role:

    The broadly accepted figure seems to be 3000-4000km with a payload of 1000-650kg, although i’m starting to get serious doubts if such a conversion would be easy to implement (the obviously fragile nature of the missile-structure, if only two-staged, could perhaps turn out to be counterproductive considering a higher payload than ~200kg and/or a range-optimized trajectory…).

  66. Gridlock (History)

    http://angryarab.blogspot.com/2009/02/iranian-missiles-technology.html

    Suggests solid fuel – but a bit of a screed and unsourced, offered purely in case any of the rest of the post sheds light for those here with a more detailed knowledge.

  67. David Wright (History)

    Geoff,

    The model I used in my comment to Jeffrey’s initial post about the satellite launch assumed a Taepodong-1 model (Nodong first stage and Scud variant second stage) with a small third stage with a mass of about 1 ton. So my relatively low burnout speed for the 2nd stage (3.5 km/s) is because the first two stages are lifting the third stage + satellite. This allowed me to see how much delta-V would be required by the third stage, and it looks reasonable. (My nubmers for the TD-1 came from fitting to data from the Aug 1998 launch).

    If instead I just use a 2-stage missile with a small payload, then the burnout speed will be higher. But even if I assume a stage 1 Isp of 250s and stage 2 Isp of 270s, which is significantly better than the TD-1, I can get something like a 6 km/s burnout speed, roughly consistent with your model. Since that is still well below the 7.7 km/s needed for orbit, it looks to me like they needed a small third-stage engine.

    David

  68. Jeffrey Lewis (History)

    All:

    I am not psyched that Geoff congratulated Iran. (“like sending Russia a thank you note for JOE 1” — that was brilliant.)

    I also, however, think it is important to have a respectful tone — which I think can stop short of congratulations.

    So, having said that, I’d like to suggest that we stop discussing the tone of the remarks and focus on whether the rocket had 2 or 3 stages and other technical questions.

  69. Pedro

    This effectively confirms that the Safir had a pause-phase and re-ignited under zero-gravity conditions, with the navigation systems working as expected.

  70. Jim Oberg (History)

    From the seesat list, another observation that suggests a large, second-stage-sized booster, in orbit:

    Observation of Iranian Booster
    From: Gerhard HOLTKAMP (grd.holtkamp@t-online.de)
    Date: Thu Feb 05 2009 – 18:37:27 UTC

    Clouds prevented me from observing the Iranian satellite this evening but half
    an hour later it was clear for me to observe the booster (2009-004B, #33507)
    passing Delta Cyg at 18:02:00 UT, 5-FEB-09 and to follow it for about one
    minute with 10×50 binoculars. I did not do any timings but every 10 seconds or
    so the object brightened for some 3 seconds by about 2 magnitudes to mag 2.5
    or mag 3 and then dropped back to something like mag 4.5. This periodic
    brightening seemed to be quite regular during the short 1 minute intervall of
    my observation. I better be prepared to take proper timings next time I get a
    chance!

    Gerhard HOLTKAMP
    Darmstadt, Germany
    49.8822 N, 8.6558 E

  71. Amir

    I had an visual observation (using binoculars) of the final-stage of Safir-2 (not a very clear sky). I estimate its brightness at its max elevation of 37° to be 3.3+-0.5. I should have a better observation tomorrow as its max elevation is 68° at my location. Fast inspection of photos I captured suggest that I have not took its picture! or it was too dim for the bright sky after sunset. I will try tomorrow as well.

    Calgary, AB, Canada

  72. Azr@el (History)

    Maybe the kick spring or the opening of the aero shell injected some angular momentum into the system causing the booster to cartwheel. Simple rotation along the axis of flight shouldn’t cause the albedo changes to the degree you’ve observed considering the body seems to have generally the same reflectivity save for a small green and red patch.

  73. Jim Oberg (History)

    If we are moving towards the conclusion that Safir-2 was a two-stage vehicle with orbital capability, what does that imply for the Safir-1 last year that was widely reported as a satellite launch attempt that failed. As I recall, the primary argument against that interpretaton was that it was only a two-stage vehicle and we all knew a two-stage Safir would be unable to orbit a satellite. Are we changing our minds now?

  74. Hamed (History)

    Hi
    Just to let you know that last night there was a live program on channel 6 (INN) in Iran. One of the scientist told that it was a two stage rocket. The first stage went up to 67 kilometer and crashed some 700 kilometer south east of Tehran in a desert. The second has been ignited and injected Omid into its LEO orbit. So it is officially a two-stage rocket.

  75. Tal Inbar

    to Jim (and others?)

    I don’t know why it is hard to believe that the Safir launch vehicle (BTW, I don’t refer to it as Safir 1 and Safir 2 – Safir launcher is the same model that presented on February 4 2008, launched on November 08 and on February 09).

    The launch of November 08 was a failure because the separation of the second stage from the first stage was unsuccessful – there are plenty of evidences about that.

    Several opinions presented here on various Iranian missile discussions were wrong, so after more information becomes available, SOME people has to shift their opinions and GUESSTIMATES.

    It was true about the Sejil/Ashura, and it is also true regarding the Safir.

    The claims about a kick motor were presented by some are simply wrong, as there are no indications by pictures and by means of Telint.

  76. Azr@el (History)

    What if the first stage fuel was Kerosene and the oxidizer was 50/50 N2O4/NHO3; that would have an energetic enough ISP to allow a two stage to orbit launch.