First up this week was the launch of CAS 500-1. On March 22 at 06:07 UTC, a Soyuz 2.1a/Fregat took off from pad 31-6 at the Baikonur Cosmodrome. It was very overcast that day, so the rocket disappeared into the clouds shortly after launch, and live footage was replaced by animation. The launch was conducted by GK Launch Services, a commercial company owned by Glavkosmos, which is itself a subsidiary of Roscosmos. This seemingly unusual setup allows Roscosmos to support commercial launches.

The rocket headed north into a 498-km Sun-synchronous orbit (SSO). This orbit is useful for imaging satellites like CAS 500 because it allows the spacecraft to pass over a location at the same solar time each day. As Sun-synchronous orbits increase in altitude, they also increase in inclination. A 500-kilometer SSO is inclined to around 97 degrees, which is very slightly retrograde. At their extreme, SSOs can be inclined to 142 degrees.

Before I talk about the payloads, I wanted to take a moment to point out the rocket’s paint job. Usually, GK Launch Services paint their rockets with an orange and grey color scheme. This time the Soyuz 2.1a was painted white and blue. Roscosmos shared that: [t]he inspiration for the new paintwork was the prototype of the Vostok launch vehicle, which is located at [the] VDNKh [Space Pavilion] in Moscow. It is painted white, and when launched, the rocket looks white from the frost covering the liquid oxygen tanks. On the Vostok launch vehicle 60 years ago, the first cosmonaut of the planet Yuri Gagarin went on a flight from the Baikonur cosmodrome.

On to the payloads! This 1,935th R7-derived Soyuz carried 38 satellites, ranging from 1U nanosatellite to 500 kilograms, to orbit. The missions are varied and include communications and technology demonstrations, space junk removal tests, imaging, and more.

The biggest satellite, CAS500-1, is the first of a pair of imaging satellites for Korea Aerospace Research Institute, the South Korean space agency. CAS500’s main imager, Advanced Earth Imaging Sensor System, will have a ground resolution of two meters in color mode and half a meter in panchromatic mode. It has a planned mission duration of four years.

I don’t have time to talk about all 37 of the smaller satellites, so the team and I picked out a few that looked interesting to us.

We get a lot of questions about space junk, so it definitely felt appropriate to talk about the ELSA-d Chaser/Target pair of satellites. These satellites were built by Astroscale, a Japanese company developing orbital debris removal satellites. They will demonstrate their system by first deploying the Target, which is equipped with a laser retroreflector and other systems. Then the Chaser will be deployed to rendezvous with the Target. The Chaser will conduct three increasingly complicated rendezvous maneuvers as the mission progresses.

One of our team members was really excited about the CubeSat Astronomy by NASA and Yonsei using the Vision ALignment Coronagraph program, also known as CANYVAL-C. CANYVAL-C is a two CubeSat mission designed to demonstrate that CubeSats can be used for solar astronomy. A 1U CubeSat named Timon is equipped with an optical camera for taking solar pictures. A 2U CubeSat named Pumbaa acts as a coronagraph, occulting the Sun, much like the Moon blocks the Sun during a total solar eclipse seen from the Earth. This allows the camera to only image the fine outer solar atmosphere. The two satellites were developed by Yonsei University in South Korea working with NASA.

Another interesting set of smallsats on the mission are the GRUS 1B, C, D, and E satellites. No, there’s no error with our counting; GRUS 1A was launched in 2018. These were a bit bigger, coming in at 100 kilograms each. They are Earth observation satellites that can obtain 2.5-meter ground resolution panchromatic images and 5-meter ground resolution multispectral images. The four satellites launched on the Soyuz mission will allow daily updates to Earth imagery.

More Information

Roscosmos press release (Russian)

GK Launch Services press release

Roscosmos press release (Russian)

CAS500 info page (KARI)

CAS500 info page (Gunter’s Space Page)

Roscosmos press release (Russian)

ELSA-d info page (Gunter’s Space Page)

CANYVAL-C info page (Gunter’s Space Page)

GRUS info page (Gunter’s Space Page)

GRUS info page (Axelspace)

Launch video