On February 2nd at 20:45 UTC the Russian Space Forces successfully launched a Soyuz 2.1b from the Plesetsk Cosmodrome in northern Russia. The Lotos-S is part of the Liana system which is replacing the Soviet-era Tselina-2 series of satellites. This was the 1,931st launch of an R7-based Soyuz rocket since 1957.

The primary mission for Lotos is ELINT, which is short for “Electronic Intelligence”. To put it simply, Lotos is a spy satellite. This is why we really don’t have a lot of publicly-available information to share. However, I can talk a little about ELINT in general.

Basically, ELINT starts with recordings of any and all information about electromagnetic signals: the frequencies, timing, durations, directions, intensities, and so on. Then you compare that to everything else you know about the device, hardware type it belongs to, and the military units that may possibly be using it. From there you compare all of that to where it’s being used, and to what is going on around it, such as things like deployments or military maneuvers.

From the combination of all these things you know, you can sometimes learn very useful information, like whether or not you can translate the signals themselves. For instance, you might discover that a satellite has synthetic aperture radar capability you didn’t know about from the types of signals it emits, or you might find out which naval groups are using which signaling channels, or which particular ground stations control which military units.

Why would something like this be useful? What’s the point of knowing a bunch of information about the signal, but not the information in the signal? Pretend you’re on a ship headed from North America to the UK during World War II. German U-Boats were known to track and sink Allied ships so the UK couldn’t stockpile goods that would be needed to survive a series of land battles. The Germans were finding the Allied ships using the Allied radio signals, and the Allied ships were able to chase down or avoid U-Boats because of the German radio signals. Neither side needed to know what was being communicated over the radio to achieve their aim.

And now, for something a bit different. The majority of the launches we talk about on Rocket Roundup are orbital launches. But those aren’t the only type of launches. Rockets can also be launched on suborbital trajectories. This means the rocket may or may not reach space by crossing the Kármán line at 100 kilometers, but they definitely do not achieve orbit. Most suborbital launches don’t attract much attention, despite their being an important part of fields of study like atmospheric research and meteorology.

More Information

Russian Military press release (Russian)

Roscosmos press release (Russian)

NASA Spaceflight article

Launch video