warning is a google translation. of the original
An early concept of the 2.4 m diameter primary mirror, which is planned to be used on the Russian new generation Hrazdan reconnaissance satellites. (Source: Kontenant magazine)
Russia currently has only two operational optical reconnaissance satellites in orbit, which may have already expired. They are to be replaced by more powerful satellites with a primary mirror of roughly the same size as those believed to be installed aboard US reconnaissance satellites, but it is unclear when they will be ready to fly. The experimental satellite, launched in 2018, is likely the predecessor to a constellation of much smaller spy satellites that will complement the images provided by larger satellites.
Soviet-era photo-
reconnaissance satellites Most of the Soviet-era reconnaissance satellites returned film in capsules to Earth. Satellites of this type continued to be used after the collapse of the Soviet Union, the last of which was launched in 2015. They were called Zenit (nine types made more than 600 flights between 1961 and 1994), Yantar (five types made nearly 180 flights from 1974 to 2015) and Orlets (two types made 10 flights from 1989 to 2006). All these satellites were designed and built by the Central Specialized Design Bureau (TsSKB) and its Progress subsidiary in Kuibyshev (renamed Samara in 1991). It was founded in 1958 as a branch of Sergey Korolev's OKB-1, and in 1974 it became independent.
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The disadvantages of film return satellites were the limited amount of film they could hold (and therefore their limited lifespan) and, more importantly, their inability to quickly return images. In 1976, the United States launched its first digital reconnaissance satellite, KH-11 / KENNEN, into orbit using CCD technology to send images to Earth in real time. 16 satellites of this type have been launched, four of which are currently in orbit. They are believed to carry a telescope with a primary mirror 2.4 meters in diameter. They are compared to the Hubble Space Telescope, but looking at the Earth rather than the Universe. They have a theoretical ground resolution of 0.15 meters. Satellites send images to Earth via data relay satellites in highly elliptical and geostationary orbits.
The Soviet Union did not launch its first optoelectronic reconnaissance satellite until December 1982. He used the Yantar film satellites platform and a traditional camera that was not capable of achieving the resolution of the KENNEN reflex telescope. It also had an infrared camera for night observation. The satellites of the first generation (Yantar-4KS1 or Terylene) with a design resolution of 1 meter from an altitude of 200 kilometers were launched nine times between 1982 and 1989. They were replaced by an improved second-generation satellite (Yantar-4KS1M or Neman). In the period from 1986 to 2000, 15 launches of sub-meter resolution satellites were carried out. The flight duration gradually increased from six months to over a year, but even this was much shorter than the multi-year missions carried out by US digital reconnaissance satellites.
Only in 1983 did the Soviet government give the go-ahead for the development of a satellite that was close to KENNEN in terms of its characteristics. To this end, the Leningrad Optical Institute LOMO was ordered to build an optical system "17V317" with a telescope with a mirror diameter of 1.5 meters. It was supposed to be installed on two different types of satellites. One, called "Sapphire", was to be built by TsSKB-Progress and launched into low orbit for flight near the atmosphere, and the other, called "Araks" (also known as "Arkon"), would be built by NPO. Lavochkin and will operate in much higher orbits with survey missions. Ultimately, Sapphire never made it into space, and the two Araks satellites that NPO Lavochkin managed to launch in 1997 and 2002 were out of order long before the expiration of their estimated service life.
"Persona"
After the failure of the second satellite "Araks" in 2003, Russia was left without any digital reconnaissance satellites in orbit and had to be content with periodic launches of satellites returning the film, which had been in orbit for no more than three months. Around the turn of the century, the Department of Defense announced a tender for a new digital reconnaissance satellite. NPO Lavochkina proposed a smaller version of the Araks, but on March 15, 2001, a contract was signed with TsSKB-Progress (in 2014 it was renamed the Rocket and Space Center Progress or RCC Progress). The contract provided for the construction of three satellites called "Persona", also known under the military designation "14F137".
After several years of delays, on July 26, 2008, the first Persona satellite was launched under the name Kosmos-2441, but Russian press reports at the time said it was lost just two months later because memory cards in its onboard computer came to unusable due to high-energy particles. The next satellite, Kosmos-2486, equipped with improved electronic components, entered orbit on June 7, 2013. Assumptions in the Russian press that problems with this satellite soon arose were confirmed by court documents published in 2017. Orbital tests of the satellite were interrupted from August 2013 to February 2014 due to unspecified problems on board and were not completed until October 2014 [1] Persona # 3 (Cosmos-2506) launched on June 23, 2015. , into an orbit synchronized with the orbit of the second satellite,to maximize coverage of areas of interest on Earth. According to the same court documents, it also encountered technical problems during the initial tests in orbit and was not operational until November 2016.
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The Persona platform appears to be a derivative of the Yantar-4KS1M platform and is believed to include improvements that have significantly increased the service life. In one article published by RKT-Progress in 2016, presumably describing the Person, the satellite has a lifespan of five years [2]. Although Persona is not mentioned by name, the article refers to a satellite orbiting the Earth in a 730 km orbit at 98.3 ° to the equator, which is the exact parameters of Persona's orbit. The resolution of the optical system on the ground is 0.5 meters. The optical system was developed by LOMO and has been identified by several sources as "17V321", although court documents published in 2012 refer to it as "14M339M".
The Russians have never published drawings or images of Persona, but a fuzzy photograph from the ground of the first satellite of Persona, taken by a British amateur observer in 2008, gives at least a vague idea of its appearance. It looks like a scaled-down version of the Hubble Space Telescope with solar panels installed parallel to the satellite's hull. This configuration of solar panels is also seen in the patent describing the Persona solar array deployment mechanism. [5]
Photo from Earth and artist's presentation of the first satellite "Persona". (Credit: John Locker) (The specified website is no longer online)
The civilian version of Persona may become Resurs-PM, which should begin replacing the currently operating Resurs-P remote sensing satellites in 2023. The declared orbit of these satellites is practically identical to that of the Persona. The platform is most likely very similar, although the solar panels are installed differently. Like Persona, Resurs-PM will use a LOMO telescope with a 1.5-meter main mirror, but with a different optical assembly, using the Ritchie-Chretien two-mirror telescope.
Earth remote sensing satellite "Resurs-PM". (Credit: RCC Progress)
Despite an unsuccessful start after the launch of Kosmos-2486 and Kosmos-2506, both satellites seem to have been working normally since then. However, if their design life is indeed five years, both have already exceeded it. While they may well continue to operate for several more years, Russia cannot afford the risk of losing the high-resolution imaging capability offered by these satellites and is actively working to upgrade its fleet of spy satellites.
Hrazdan
After the publication of the article in Kommersant, more details about the project did not appear in the Russian press [6]. However, a significant amount of information about the project can be obtained from various Russian online sources.
From publicly available procurement documents, it follows that the project officially began on June 19, 2014 with the signing of a contract between the Ministry of Defense and the Progress RCC. The second contract for the project was awarded by the same two parties on September 26, 2016. Perhaps the original contract was only for the completion of the preliminary design of the satellite, while the second was for the actual construction of the satellites. This could explain why, immediately after the signing of the 2014 contract, the design of some systems was assigned to more than one subcontractor, apparently on a competitive basis.
While individual satellites are designated by the military code name "14F156", the code name for the entire project ("space system" in Russian terminology) is "14K046". As can be seen from the online document "Progress RCC", the design of the satellite takes place in department No. 1032 of the RCC "Progress" under the leadership of the chief designer Oleg Fedorenko [7].
The optical payload of "Hrazdan" (the so-called "electro-optical complex" or OEC) is named "Sevan", in honor of the Armenian lake, from which the Hrazdan River originates. In July 2014, Progress RCC signed contracts for the preliminary design of Sevan with two telescope manufacturers - KMZ and LOMO. [8] However, there is no trace of LOMO in the later Sevan documents, which indicates that KMZ was selected as the sole supplier. Unlike LOMO, KMZ is part of the powerful Shvabe holding, which unites several dozen organizations that make up the core of the Russian optical industry. Perhaps this helped her to get a prestigious contract for Sevan, while LOMO had to be content with the contract for the Telescope of the Resurs-PM satellite, which in a sense is a repetition of the work he had done earlier for Persona.
It looks like KMZ started developing the technology for Hrazdan's optical loading even before the project officially kicked off. In December 2013, he won a tender organized by Roscosmos under the name Mirror-KT (Mirror-Space Telescope). The goal was described as "the development of technology for the production of light primary mirrors for modern large space telescopes with very high resolution for remote sensing of the Earth" [9].
All this means that the size of the Sevan's main mirror is equal to the size of the mirror, which is believed to have been installed on the American KH-11 / KENNEN satellites back in 1976.
The challenge was to develop a mirror with a diameter of up to 2.5 meters, as well as a composite structure for mounting the mirror. They must be able to stay in orbit for at least seven years. According to the documentation, Zerkalo-KT was prematurely completed in February 2015, but it is clear from other sources that KMZ continued to work on the system in subsequent years. A possible explanation for this is that Zerkalo-KT began as a civilian project funded by Roscosmos, and that the space agency stopped cash flow in early 2015 when the mirror became part of the Ministry of Defense's Hrazdan project. A drawing of the mirror, conceived within the framework of Mirror-KT, was published in an article at the end of 2014 (see the figure at the top of the article) [10].
As can be determined from online procurement documents, Kovrov Mechanical Plant received final approval for the development of Sevan on September 30, 2016, four days after the Ministry of Defense and RCC Progress signed their second contract for Hrazdan. KMZ was supposed to act as a subcontractor for the Progress RCC as a payload supplier, but instead it received a contract directly from the Ministry of Defense, which apparently wants to transfer the development of Sevan under its direct control.
While KMZ is responsible for integrating the optical load, the mirrors are manufactured by the Lytkarino Optical Glass Plant (LZOS). LZOS already teamed up with KMZ for the Zerkalo-KT project in 2014, possibly even before the approval of Hrazdan [11]. At least two LZOS publications confirm their involvement in Hrazdan [12]. In some issues of the corporate magazine of the Spektr company, the mirrors of Sevan are clearly mentioned, but the project itself is not mentioned. One mentions a “special optics kit” consisting of a 2.4 meter primary mirror, a 0.54 meter secondary aspherical mirror and an aspherical off-axis tertiary mirror [13]. Most likely, this means that the Hrazdan telescope is a three-mirror Korsh anastigmat.
In other issues of the "Spectrum" mention is made of a container required to transport a 2.35-meter mirror, which must be the exact diameter of the primary mirror (2.4 meters is a rounded number) [14]. This is confirmed by procurement documents, which may be associated with "Sevan" and contain drawings of all three mirrors inside the containers. Based on this, the diameter of the tertiary mirror can be estimated at about 0.40 meters [15].
Drawings of the main, secondary and tertiary mirrors of Sevan in shipping containers. (Source: Russian government procurement website)
All this means that the size of the Sevan's main mirror is equal to the size of the mirror, which is believed to have been installed on the American KH-11 / KENNEN satellites back in 1976. It has nearly the same diameter as the two primary mirrors that National Intelligence donated to NASA in 2012 for use aboard astronomical satellites (one of which will fly on the Nancy Grace space telescope in Rome, formerly known as the Wide Field Infrared Survey Telescope) ... It was spare equipment left over from the NRO spy satellite project. The mirrors donated were reported to have been part of an assembly of three mirrors, but the third mirror was not included in the donation.
A similar diameter of the Sevan's primary mirror does not necessarily mean the same terrain resolution as American spy satellites. Other factors that come into play are the quality of the mirror and image sensors. The material from which the main mirror is made (as well as, presumably, others) is SO-115M, also known as Sitall or Astrositall. It is a crystalline glass-ceramic material developed back in Soviet times and used for the manufacture of many Russian space mirrors, including the 1.5-meter mirrors on the Araks and Persona. LZOS publications confirm that materials such as silicon carbide (used at ESA's Herschel and Gaia observatories) and beryllium (used by the James Webb Space Telescope) have superior performance.
The CCD image sensors to be used by Sevan were identified as Kem-PKh (for panchromatic images) and Kem-MS (for multispectral images). [17] Kem is the name of a river in the Republic of Karelia in northwestern Russia. The sensors are manufactured at NPP Elar, which also produces CCDs for other Russian Earth imaging satellites, including Persona, Resurs-P and Resurs-PM. In articles published by NPP Elar, the pixel size is 9x9 µm² for Chem-PC and the pixel size is 18x18 µm² for Chem-MS. The same sizes of CCD pixels are observed for the Resurs-PM high-resolution panchromatic imaging system and the medium-resolution multispectral imaging system, which indicates the generality of the design [18].
The main power plant of "Hrazdan" uses a liquid fuel engine developed by KB Khimmash, which is part of the Khrunichev Center [19]. According to the available data, it was a modified version of the propulsion system flown on the Resurs-P satellites. The satellites will also carry an electric propulsion system. The manufacturer cannot be determined with certainty, but it is known that a company called NIIMash was tasked with making xenon tanks for the system [20]. According to one of the NIIMash documents, the system will be used for accurate orbit correction and will improve the ground resolution of the onboard optical complex [21]. Most likely, this means that the perigee of the "Hrazdan" will at least periodically descend to heights where an electric propulsion system is required to counteract atmospheric resistance.This is reminiscent of tests carried out in 2017–2019 by Japan with an experimental imaging satellite called Tsubame, or an ultra-small test satellite, which used ion engines powered by xenon engines to combat aerodynamic drag as it descends to 167 kilometers. Presumably, the Hrazdan satellites will fly in elliptical orbits, similar to those of the American digital reconnaissance satellites, and not in the circular 730-kilometer orbits used by Persona.which used ion engines on xenon engines to combat aerodynamic drag when descending to an altitude of 167 kilometers. Presumably, the Hrazdan satellites will fly in elliptical orbits, similar to those of the American digital reconnaissance satellites, and not in the circular 730-kilometer orbits used by Persona.which used ion engines on xenon engines to combat aerodynamic drag when descending to an altitude of 167 kilometers. Presumably, the Hrazdan satellites will fly in elliptical orbits, similar to those of the American digital reconnaissance satellites, and not in the circular 730-kilometer orbits used by Persona.
Also on board will be torque control gyroscopes that will allow satellites to navigate without consuming fuel. They will be built by the Scientific Research Institute of Command Instruments (NIIKP) in St. Petersburg. Called SGK-250, they have the same characteristics as gyroscopes on the Resurs-P and Persona satellites, and will also be installed on Resurs-PM. [22]
Another subcontractor for the Hrazdan project is the Scientific Research Institute of Precision Mechanics (SRI TM), which is developing the so-called Information Elimination System (SLI). [23] It is defined on the company's website as a stand-alone system that can erase information (including so-called "encoded information") in the event that certain parameters "exceed acceptable limits" and appears to contain a set of specialized sensors for continuous monitoring of various onboard satellite systems.
While Hrazdan's optical payload is likely to be heavier than Persona's, the satellites should remain within the launch capacity of Soyuz-2-1b, the most powerful rocket in the Soyuz family of launch vehicles, which has also been used to launch satellites. "A person". The satellite's heavier mass can be offset by using an elliptical rather than a circular orbit. The launches will be carried out from the Plesetsk military cosmodrome.
In a blog post at the end of 2016, the VNIIEM designer said that excellent images from the first SkySat satellite in 2013 prompted Russian companies (including Reshetnev's ISS) to start developing plans to create similar small satellites in 2014.
According to the procurement documentation, construction of two Hrazdan satellites is currently underway. The documentation published in September 2017 indicated possible launch dates in late 2020 and late 2021, but those dates have likely shifted since then. [24] In addition to potential technical problems, Hrazdan, like many other Russian space projects, could well face delays both due to budgetary problems and due to the sanctions imposed by the West, which made it difficult to supply foreign electronic components to the Russian space industry. Work is now underway on a much smaller type of spy satellite, which is supposed to guarantee constant access to high-resolution images for the Russian military, even if the Persona satellites go down in orbit beforehow Hrazdan will be ready to launch.
EMKA and Razbeg
On March 29, 2018, Russia launched a small military satellite from Plesetsk using the Soyuz-2-1v launch vehicle, a lightweight version of the Soyuz launch vehicle without four side blocks. Billed as Kosmos 2525, it was launched into orbit about 320 x 350 kilometers with an inclination of 96.64 °. Online tenders for transporting the satellite to Plesetsk identified it as EMKA and linked it with the All-Russian Research Institute of Electromechanics (VNIIEM), a manufacturer of Earth remote sensing and meteorological satellites. The documents trace the history of the project to the contract signed between the Ministry of Defense and VNIIEM on October 23, 2015 [25]
In the 2016 VNIIEM annual report, EMKA stands for "experimental small satellite", adding that it will serve as the basis for the "Earth remote sensing space complex", clearly used here as a cover term for military photographic reconnaissance. [26] EMKA is probably the same satellite that is mentioned in several articles of VNIIEM in 2014–2015. as a satellite "Star". One described it as a 150kg experimental predecessor to the slightly larger 250kg satellite (MKA-B), which can capture high-resolution images for both civilian and military purposes. MKA stands for Small Satellite and B stands for High Resolution. The article compares Zvezda and MKA-B with the first of a series of American commercial Earth imaging satellites SkySat-1 with a maximum resolution of 0,9 meters in panchromatic mode. There is also a drawing MKA-B,
Satellite MKA-V. (credit: VNIIEM)
SkySat-1. (Credit: Planet Lab)
"Zvezda" is also mentioned on the website of the company SKTB Plastik, which has drawings of the camera body that it built for the satellite. [28] The shape and size of the body exactly matches the dimensions of the high-resolution camera described in two articles published in 2015, which stated that this is a payload for another small high-resolution satellite called ISS-55, proposed at the time by ISS Reshetnev, the most known as a manufacturer of communication and navigation satellites [29]. The camera, created by the Belarusian optical company OJSC Peleng, has a maximum resolution of 0.9 meters in panchromatic mode, which is identical to that of SkySat-1. In a blog post at the end of 2016, the VNIIEM designer said that the excellent images obtained from the first SkySat satellite in 2013prompted Russian companies (including the Reshetnev ISS) to start developing plans to create similar small satellites in 2014 [30].
High-resolution camera for the Zvezda and ISS-55 satellites. (Credit: Proceedings of the MAI)
From all this, it can be concluded with a fairly high degree of confidence that the first launches of SkySat satellites in 2013 and 2014 inspired VNIIEM and ISS Reshetnev to create small high-resolution remote sensing satellites (Zvezda and ISS-55) with identical optical system in the payload of JSC "Peleng". Initially, they could have been offered to Roskosmos as civilian remote sensing satellites, but they also attracted the attention of the Ministry of Defense, which at the end of 2015 selected the Zvezda satellite for further development, renaming it EMKA. This also explains why, after 2015, there are no more descriptions of "The Star" in the open literature.
Kosmos-2525 is still operational, continuing to perform regular engine corrections to maintain its orbit. One of the mission objectives was to observe ground-based optical calibration targets developed at the Moscow Polytechnic University [31].
A drawing from the patent showing calibration targets likely used on the EMKA / Kosmos-2525 satellite.
The targets function like a slit chart. The smallest band group that can be resolved indicates the resolution limit for the optical instrument being used. Calibration targets like these can be seen in several places in the United States (for example, at Edwards Air Force Base), but the novelty of the new targets is that they are not painted on the asphalt, but on foldable polymer sheets that can be used in a variety of locations.
The operational successor to Kosmos-2525 is probably being developed as part of a project designated in the procurement documentation as Run-up, handed over to VNIIEM by the Ministry of Defense on November 1, 2016. [32] Available documents only show that Run-up is a small satellite, and it is also assumed that it shares some design features with EMKA, indicating that this is the same satellite that was named MKA-V in the previously mentioned VNIIEM publication. Most likely, "Takeoff" is a constellation of small satellites for acquiring images, which, if necessary, can close the gap between "Persona" and "Hrazdan" and, ultimately, complement the images provided by large spy satellites. Likewise, the US National Intelligence Agency complements images captured from its own satellites,lower resolution photographs from commercial remote sensing satellite operators.
A key component of any real-time satellite imagery system is a data relay satellite network that can transmit images from reconnaissance satellites for extended periods of time when they are out of sight of ground stations. The Persona satellites worked in conjunction with two military data relay satellites called the Harpoon, also known as 14F136. Built at the Reshetnev ISS, they were launched in September 2011 and December 2015 after many years of delays (the project started in 1993). The second satellite, as is known, was used for experiments with laser communication with the third satellite "Persona" using the onboard laser terminal LT-150. A total of two Harpoon satellites were manufactured, and their estimated service life is unknown.To ensure permanent coverage, a constellation of at least three satellites is required.
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ISS Reshetnev is currently working on new military communications satellites called Hercules and Giant, which will carry large antennas the company is developing. The largest of them has an antenna diameter of 48 meters, although it is not known for certain if it is intended for any of these satellites. Hercules has been described by one source as a data relay satellite and is likely to be the successor to Harpoon. [33] Project Hercules began in 2014, but there is no indication that it is close to launching its first satellite. The satellites will have to be launched into orbit by the Angara-A5 carrier rocket, whose test flights from Plesetsk are scheduled to resume later this year after a six-year break. Russia also has three Luch-5 data relay satellites in geostationary orbit,but they were ordered by Roskosmos, and it is unclear whether they are used to transmit information from the satellites of the Ministry of Defense. ISS them. Reshetneva recently received a contract for an improved version of these satellites called Luch-5VM, which is expected to be launched no earlier than 2024. The technical characteristics of Luch-5VM do not specifically mention the possibility of relaying for military satellites.
Russia relies on two aging Persona satellites for high-resolution imaging for the Defense Ministry. Both appear to be functioning normally after overcoming major challenges during the initial orbital tests. However, there is no guarantee that they will continue to operate until the new generation Hrazdan satellites are ready. This may be the reason why the decision was made to develop a much smaller and simpler type of spy satellite (Run) that could help bridge the gap before Hrazdan and ultimately complement the images provided by the larger satellites. The probable experimental predecessor of these satellites (EMKA / Kosmos-2525) reached the launch pad just 2.5 years after approval, suggestingthat operational satellites may also be ready for launch relatively soon. Still, the resolution offered by the smaller satellites will not match the resolution of Hrazdan. The Department of Defense also operates two four-ton observation satellites called Bars-M (launched as Kosmos-2503 and 2515), but they are used for low-resolution cartographic imagery.
To complicate matters further, Russia currently does not have radar imaging satellites (civilian or military) capable of seeing through cloud cover and observing at night. NGO them. Lavochkina is working on a series of special military satellites for obtaining radar images called "Araks-R", but it is not known when they will fly. A new generation of specialized military satellites for relaying data required to support the reconnaissance satellite program may also be out of service after some time. In short, it's safe to say that Russia's current capabilities in space exploration are far inferior to those of the United States and China. At worst.
For more information, see the Hrazdan, EMKA and Takeoff threads on the NSF forum. They are updated with new information as it becomes available.
Links (working links can be found in the original article)
1. Documents (in Russian), published in 2017-2018, describing the court case between RCC Progress and Research Institute of TP.
2. The article was published by the Progress RCC and the Samara National Research University in the Bulletin of the Samara State Aerospace University, 2016/2.
3. Documents (in Russian), published in 2012-2013, describing three trials (1, 2, 3) between LOMO and NII TM.
4. Presentation of LOMO in 2007
5. Patent published by TsSKB-Progress in 2011
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The concluding comment on Ars Technica's article, which ranks Russia on a par with India, was particularly eloquent.
Duane Day The
National Intelligence Agency decided (in fact, it was the CIA) that the KH-11 KENNEN needed a 2.4 meter mirror. We do not know why they chose this diameter (although we can make some assumptions), but it seems that this is what they have adhered to for almost five decades.
And now the Russians have chosen for their large reconnaissance satellite a mirror diameter almost identical to the American one.
Interesting, huh?