DS-U2-GK (Kosmos 261) [Yuzhnoye]
Official name COSMOS 261
Alternative name Cosmos-261
Cospar ID 1968-117A
Norad ID 3624
Launch date 1968-12-19
Launch site PKMTR
Launch vehicle Kosmos-2
Country/Organization USSR
Type application Science, Magnetosphere
RCS size UNKNOWN
Decay date 1969-02-12
Shape Ell
Mass (kg) 343.9
Height (m) 2.1
Width (m) 1.5
Depth (m) 1.8
Span (m^2) 2.1
Lifetime 40 days (design)
Contractors Yuzhnoye
Configuration DS Bus
Power 4 deployable fixed solar arrays, solar cells, batteries

The DS-U2-GK satellites were Soviet geophysical research satellites launched as part of the Dnepropetrovsk Sputnik program.

These satellites were used to study the density of air in the upper atmosphere, investigate aurorae and ionospheric plasma motion.

The first satellite of this type, Kosmos 261 was launched on 19 December 1968 on a Kosmos-2 booster from Plesetsk. It decayed from orbit and reentered the atmosphere on 12 February 1969.

The second satellite of this type, Kosmos 262 was launched on 13 June 1970 on a Kosmos-2 booster from Plesetsk. It decayed from orbit within a few weeks of its launch, reentering the atmosphere on 25 July 1970.

Satellite COSPAR Date LS Launch Vehicle Remarks
COSMOS 261 1968-117A 1968-12-19 PKMTR Kosmos-2
COSMOS 348 1970-044A 1970-06-13 PKMTR Kosmos-2