Kosmos 261 (Russian: Космос 261 meaning Cosmos 261), also known as DS-U2-GK No.1, was a Soviet satellite which was launched in 1968 as part of the Dnepropetrovsk Sputnik programme. It was a 347-kilogram (765 lb) spacecraft,[1] which was built by the Yuzhnoye Design Bureau, and was used to study the density of air in the upper atmosphere, and investigate aurorae.[1] Kosmos 261 set the way for the Intercosmos Program. Hungary, Poland, Romania, Czechoslovakia, DDR and Bulgaria were the six Soviet Bloc countries that collaborated in the experiments on board the satellite.[2]
Mission type | Aeronomy Auroral |
---|---|
COSPAR ID | 1968-117A ![]() |
SATCAT no. | 03624![]() |
Spacecraft properties | |
Spacecraft type | DS-U2-GK |
Manufacturer | Yuzhnoye |
Launch mass | 347 kilograms (765 lb)[1] |
Start of mission | |
Launch date | 19 December 1968, 23:55:00 (1968-12-19UTC23:55Z) UTC |
Rocket | Kosmos-2I 63SM |
Launch site | Plesetsk 133/1 |
End of mission | |
Decay date | 12 February 1969 (1969-02-13) |
Orbital parameters | |
Reference system | Geocentric |
Regime | Low Earth |
Perigee altitude | 201 kilometres (125 mi) |
Apogee altitude | 611 kilometres (380 mi) |
Inclination | 71 degrees |
Period | 92.68 minutes |
A Kosmos-2I 63SM carrier rocket was used to launch Kosmos 261 into low Earth orbit from Site 133/1 at the Plesetsk Cosmodrome.[3] The launch occurred at 23:55:00 UTC on 19 December 1968, and resulted in the successful insertion of the satellite into orbit.[4] Upon reaching orbit, the satellite was assigned its Kosmos designation, and received the International Designator 1968-117A.[5] The North American Aerospace Defense Command assigned it the catalogue number 03624.
Kosmos 261 was the first of two DS-U2-GK satellites to be launched.[1][6] It was operated in an orbit with a perigee of 201 kilometres (125 mi), an apogee of 611 kilometres (380 mi), 71 degrees of inclination, and an orbital period of 92.68 minutes.[7] It decayed from orbit and reentered the atmosphere on 12 February 1969.[7]
← 1967 · Orbital launches in 1968 · 1969 → | |
---|---|
Surveyor 7 | Explorer 36 | Kosmos 199 | OPS 1965 | OPS 5028 | Kosmos 200 | Apollo 5 | OPS 2243 · OPS 6236 | Kosmos 201 | E-6LS No.112 | Kosmos 202 | Kosmos 203 | OPS 7034 | Zond 4 | OGO-5 | Kosmos 204 | Kosmos 205 | Explorer 37 | DS-U1-Ya No.1 | OPS 5057 | Kosmos 206 | OPS 4849 · OPS 7076 | Kosmos 207 | Kosmos 208 | Kosmos 209 | Kosmos 210 | Apollo 6 | OV1-13 · OV1-14 | Luna 14 | Kosmos 211 | Kosmos 212 | Kosmos 213 | OPS 5165 | Kosmos 214 | Kosmos 215 | Kosmos 216 | Molniya-1 No.10 | 7K-L1 No.7L | Kosmos 217 | Kosmos 218 | Kosmos 219 | OPS 1419 | Kosmos 220 | ESRO-2B | Nimbus B · SECOR 10 | OPS 7869 | Kosmos 221 | Kosmos 222 | Kosmos 223 | Kosmos 224 | Sfera No.12L | OPS 5138 | Kosmos 225 | Kosmos 226 | IDCSP 20 · IDCSP 21 · IDCSP 22 · IDCSP 23 · IDCSP 24 · IDCSP 25 · IDCSP 26 · IDCSP 27 | Strela-2 No.3 | Kosmos 227 | OPS 5343 · OPS 5259 | Kosmos 228 | Kosmos 229 | Explorer 38 | Kosmos 230 | Molniya-1 No.13 | Kosmos 231 | OV1-15 · OV1-16 | Kosmos 232 | Kosmos 233 | Kosmos 234 | OPS 2222 | OPS 5187 | OPS 5955 | Explorer 39 · Explorer 40 | Kosmos 235 | ATS-4 | ESSA-7 | Orbiscal 1 · OV5-8 · Gridsphere 1 · Gridsphere 2 · Gridsphere B · Gridsphere R · LCS-3 · LIDOS · SECOR 11 · SECOR 12 · Radcat · P68-1 | Kosmos 236 | Kosmos 237 | Kosmos 238 | Kosmos 239 | OPS 5247 | Kosmos 240 | Zond 5 | Kosmos 241 | OPS 0165 · OPS 8595 | Intelsat III F-1 | Kosmos 242 | Kosmos 243 | LES-6 · OV2-5 · ERS-21 · ERS-28 | Kosmos 244 | Kosmos 245 | ESRO-1A | Molniya-1 No.14 | OPS 0964 | Kosmos 246 | Kosmos 247 | Apollo 7 | Kosmos 248 | Kosmos 249 | OPS 4078 | Soyuz 2 | Soyuz 3 | Kosmos 250 | Kosmos 251 | Kosmos 252 | OPS 1315 | OPS 5296 | Pioneer 9 · ERS-31 | Zond 6 | Kosmos 253 | Proton 4 | Kosmos 254 | Kosmos 255 | STV-1 | Kosmos 256 | Kosmos 257 | OPS 6518 | HEOS-1 | OAO-2 | Kosmos 258 | OPS 4740 · OPS 7684 | Kosmos 259 | ESSA-8 | Kosmos 260 | Intelsat III F-2 | Kosmos 261 | Apollo 8 | Kosmos 262 | |
Payloads are separated by bullets ( · ), launches by pipes ( | ). Crewed flights are indicated in underline. Uncatalogued launch failures are listed in italics. Payloads deployed from other spacecraft are denoted in brackets. |
![]() | This article about one or more spacecraft of the Soviet Union is a stub. You can help Wikipedia by expanding it. |