EKS/Tundra early warning satellites

[Blackstar]

Take A Rare Look Inside Russia’s Doomsday Ballistic Missile Warning System
As Russia’s early warning network marks 50 years of service, one of its satellite control centers opened its doors.
By Thomas Newdick February 15, 2021


The Russian Ministry of Defense posted a video to its various social media channels yesterday showing some of the inside workings of one of the country’s early warning facilities that watch for incoming ballistic missiles. The video appears to show the Serpukhov-15 satellite control center in Kaluga Oblast, around 90 miles southwest of Moscow, which was at the center of one of the Cold War’s most hair-raising incidents.

The video was posted online as Russia’s early warning network, designed to protect against ballistic missile attacks, celebrated its 50th anniversary. The organization that operates these systems, commonly referred to by its Russian acronym SPRN, marked the occasion in an appropriate style. The footage shows that it even apparently simulated an incoming intercontinental ballistic missile (ICBM) attack from the United States.

[B. Hendrickx]

There were several TV reports yesterday devoted to the 50th anniversary of the early warning network. One of the more interesting ones was on Zvezda TV:
https://tvzvezda.ru/news/forces/content/2021215187-Km45O.html

It has a few shots of the EKS control center at Serpukhov-15, including a view inside one of the radomes. Also shown is a map with the ground track of the Tundra satellites. This shows that the western apogee is situated right above the North American continent, which, strangely enough, is much further to the west than what is seen on online satellite tracking maps (such as the attached one of Kosmos-2541 from Heavens Above).

Other shots were taken inside the 820th Main Center for Missile Attack Warning in Solnechnegorsk-7 (the missile warning headquarters, where all the information obtained by both satellites and ground-based radars comes together). On display there is one of the Soviet-era early warning satellites.

[B. Hendrickx]

A PowerPoint presentation that appeared online recently gives an overview of current and planned optical systems for Russia’s EKS early warning satellites. 

https://ppt-online.org/881135

The presentation was compiled by the Research Institute of Electro-Optical Instrument Building (NII OEP), a daughter company of the Kometa Corporation, the prime contractor for EKS. It describes four optical systems, three of which are linked to “a space-based detection system” operating at an altitude of 40,000 km (the name EKS itself is not mentioned). This is probably a reference to both the existing EKS constellation in highly elliptical Molniya-type orbits and the future constellation in geostationary orbit (40,000 being a rounded number, in reality the apogees are slightly lower).

The four optical systems are:

- Irtysh-E:  a system with a wide-field “staring” channel for global observations and a narrow-field channel for local observations, both in the near infrared. It uses cathode ray tubes (size given is 2000x2000).
Period of NII OEP’s involvement: 2005 until now

- KAS IKSh: a wide-field electro-optical scanning system using Kosmos-IKSh photodetectors (“IK” stands for infrared and “Sh” is short for “wide-field”). The system is intended for global observations, operates in the near infrared and uses a 10x1024 pixel array with time delay integration.  Also seen in the presentation is a picture of the system’s “large-size objective lens”.
Period of NII OEP’s involvement: 2012-2015

- Irtysh-SK-OMSU: a wide-field optical/mechanical scanning system (OMSU) for global observations. Two lenses are described, one called Dixon-1 (for observations in the near and mid infrared) and another called Dixon-2 (for observations in the near infrared). It uses what are called submatrix photodetectors (10x1024) with time delay integration.
Period of NII OEP’s involvement: early 2017 until now

- Komplekt-1 Obyektiv :  a system operating in two spectral channels (near infrared and medium infrared) and intended for local observations. The lens is called Taimyr-2. The system uses  large-format matrix photo detectors (pixel array sizes given are 512x512  and 1024x1024).
Period of NII OEP’s involvement: 2017-2018

The presentation goes on to describe the scanning and staring sensors carried by America’s SBIRS early warning satellites, giving details that I’m not sure have been publicly revealed (raising the question what the source for that information is). The following slide shows a combination of scanning and staring sensors with characteristics similar to those of SBIRS. The wide-field scanning system and the narrow-field staring system are described as being “analogous” to Irtysh-SK-OMSU and Komplekt-1 Obyektiv respectively.

The presentation sums up several advantages of the lens objectives that these systems use, including their wide field of view (20° and more), their small size and compatibility with various types of detectors. Among the disadvantages are the limited diameter of the entrance pupil (no more than 300 mm), the high mass and the relatively limited spectral range. Some of these shortcomings can be eliminated by using mirror or combined mirror/lens systems, but these still require a lot of development work.


So what does all this add to our knowledge of the EKS payloads?

Irtysh-E had earlier been identified as an EKS payload. It is most likely an outgrowth of a canceled Soviet-era project and uses vidicons called LI-489E or Kater-3E provided by TsNII Elektron. See the article on EKS that I wrote earlier this year for The Space Review:
https://www.thespacereview.com/article/4121/1
Since it has been under development since early this century, it is logical to assume that this is the payload that has flown on the EKS satellites launched thus far. Irtysh is known to require a cryogenic cooling system and such a system (developed by the KB Tochmash “Nudelman” design bureau) is known to have been on board at least some of the Tundra satellites.

The KAS IKSh scanning system can be traced back to a contract signed between the Ministry of Defense and the Kometa Corporation on August 1, 2012, which called for developing an experimental version of a new-generation infrared photo detector (Kosmos-IKSh) for “phase 3” of the EKS program. See this court document:
https://kad.arbitr.ru/Card/41e1872a-1470-4be8-aa6d-086cc90fd6df
According to NII OEP’s website, Kosmos-IKSh was launched into space in 2015 and 2017, which corresponds to the first two Tundra launches (Kosmos-2510 in November 2015 and Kosmos-2518 in May 2017).
https://www.niioep.ru/pages/a-ist_vehi.html#up
However, this would seem to be contradicted by the court document, which describes it as an experimental system that was included in “technical planning for the full EKS constellation” in January 2017. At this point, it remains unclear if has already flown or is still supposed to do so on future EKS satellites.

The name Irtysh-SK-OMSU had not been seen before, but some factors indicate that it is the infrared scanning system discussed in an article published in 2016 and that it will use detectors called Granat-128 developed by NPO Orion under a contract awarded by Kometa in November 2016 (see the Space Review article). 

Komplekt-1 Obyektiv is the only of the four systems not directly linked to the “space-based detection system” and is described in the presentation as being intended for “experimental tests of large-format infrared detectors”. As can be inferred from procurement documentation, Komplekt-1 is a project that along with another one (named Progress) was assigned by Roscosmos to the Kometa Corporation on December 24, 2015 following a closed tender.  Both projects seem to have been aimed at developing large-format infrared detectors and associated optics. The work on the infrared detectors was subcontracted by Kometa to NPP Vostok (under Komplekt-1) and NPO Orion (under Progress) on March 14, 2016.

The fact that Komplekt-1 and Progress were initiated by Roscosmos and not the Ministry of Defense would indicate that there was no direct link with EKS. Possibly, these were seen as technology development projects with possible applications in future remote sensing, early warning, space surveillance and astronomical observation systems. One source linked Komplekt-1 to “space-based equipment for global monitoring of the Earth, near-Earth space and distant space”. There may be a link with a secretive space-based space surveillance system being developed under the code name KS SKKP.   

The NII OEP presentation does suggest that the technology developed under Komplekt-1 will be incorporated into EKS. It will be used for a narrow-field staring sensor that will be flown together with a wide-field scanning sensor (Irtysh-SK-OMSU).  In other words, the ultimate goal of EKS is to mimic SBIRS by installing a combination of staring and scanning sensors on a single platform, most likely in geostationary orbit. SBIRS’ scanning sensor is mainly intended to look for traditional intercontinental ballistic missile threats, whereas the staring sensor is designed to detect very low signature, short-burn-duration theater missiles. The EKS sensors may serve the same purpose.

[B. Hendrickx]

The main payload of the Tundra satellites is the Irtysh-E infrared television camera (see earlier posts here). This is a modified version of a camera that was developed late last century, but eventually never flew in space. One picture of the original Irtysh camera was posted here earlier and is attached again.

Several more pictures of the original Irtysh camera are in a newly published history of NII Televideniya, the organization that was in charge of its development and had already produced TV cameras for earlier Soviet-era early warning satellites.
https://niitv.ru/wp-content/uploads/2025/09/90_let_nii-televideniya.pdf

-upper left: the front side of the camera with optics manufactured by LOMO
-upper right: the cryogenic cooling system, developed by the Verkin Institute for Low Temperature Physics (FTINT) in Kharkov (Ukraine)
-lower left and right: images of the infrared vidicon tubes provided by TsNII Elektron. What is called the “entrance window” is said to have a record area of 30 square centimeters .

The NIIT history confirms that Irtysh ultimately did not fly until after the turn of the century. Its development continued at a branch of NIIT that was transferred in 2000 to the Kometa Corporation, the prime contractor for the Tundra satellites.

Based on available information, it would seem that the modifications made to Irtysh for Tundra were not all that significant. The Irtysh-E system still relies on vidicon tubes produced by TsNII Elektron. One major change was the replacement of the Ukrainian-built cryogenic cooling system by one provided by KB Tochmash (the former Nudelman design bureau), best known in the space community for its involvement in a number of anti-satellite systems.