Rockot launches third Geo-IK-2 satellite
More than three years after the launch of the second Geo-IK-2 satellite, the Russian space units of the nation's Air and Space Forces, VKS, is finally fullfilling its original goal of deploying two new-generation geodesic satellites in orbit. On August 30, 2019, the Rockot booster, converted from a ballistic missile, lifted off from Plesetsk launch site in Northern Russia carrying the Geo-IK-2 No. 13L satellite.
The circa 2015 depiction of the Geo-IK-2 (Musson-2; 14F31) satellite in deployed position in orbit sans thermal protection system. Credit: ISS Reshetnev
Geo-IK-2 No. 13L mission at a glance:
Developed at ISS Reshetnev in Zheleznogorsk, the Geo-IK-2 No. 13L satellite, also known by its military designation as Musson-2 and by its industrial designation as 14F31, was designed to work in tandem with its predecessor, providing very accurate measurements of the Earth's shape and its gravitational field, facilitating the cartographic work, among its other military and civilian applications.
In August 2012, ISS Reshetnev reported that Thales Alenia Space in France would supply the Sadko-3 altimeter for the Geo-IK-2 No. 3 satellite, intended to replace the original Geo-IK-2 spacecraft. According to the contract, the instrument was to be delivered to ISS Reshetnev at the end of 2014 or beginning of 2015. On Dec. 6, 2012, ISS Reshetnev announced that the company and its contractors had started the manufacturing of components for the satellite with a projected launch date in 2015 from Plesetsk Cosmodrome.
From 2015 until around the Spring of 2016, the launch of the third Geo-IK-2 satellite was expected in 2017. At the time, there were hints that the launch could be moved from Rockot to the new-generation Angara-1 rocket to resolve the problem with the supplies of the Ukrainian-built flight control system on the former vehicle.
However, with the Angara family years behind schedule, the third Geo-IK-2 mission continued slipping to June and December 2018 and, later into 2019. Only in August 2019, the Russian authorities issued the official notification to airmen to avoid areas identical to those that were closed during the previous Geo-IK-2 launch. Based on the information in the closure announcements, the liftoff was expected around 14:00 UTC (10 a.m. EDT, 17:00 Moscow Time).
Geo-IK-2 No. 13L launch profile
An approximate ascent scenario and a ground track of the Geo-IK-2 launches.
The liftoff off a Rockot booster with a Briz-KM upper stage took place on August 30, 2019, from Pad 3 at Site 133 in Plesetsk. The main engine of the first stage was ignited at 17:00:11.887 Moscow Time and moments later, the vehicle lifted off the pad. The rocket carried the Geo-IK-2 No. 13L geodetic satellite.
According to the official Russian media quoting the Ministry of Defense, the Titov Chief Test Space Center began tracking the vehicle two minutes after its liftoff.
The Russian military did not detail the flight profile for Geo-IK missions, but based on the known target orbit parameters and the information available from the original launch, some key aspects of the powered flight can be assumed.
After a few seconds in vertical ascent, the rocket headed northwest on a so-called retrograde trajectory, which took the vehicle westward, unlike most orbital missions which fly east with the rotation of the Earth. The ascent profile was designed to insert the satellite into an orbit with an inclination 99.4 degrees toward the Equator, extending from the North Pole to the South Pole of our planet. It enables remote-sensing satellites to observe the entire planet, as the globe makes a full rotation from west to east under the spacecraft's flight path every 24 hours.
According to the Russian Zvezda TV channel, the first stage of the Rockot booster separated two minutes and 2 seconds into the flight. Another 46 seconds later, the payload fairing protecting the satellite split into two halves and fell off at an altitude of more than 119 kilometers, safely beyond the dense atmosphere. Both, the first stage and the payload fairing, were to fall into the sea, north of the Norwegian Coast.
The second stage continued firing until 5.3 minutes into the flight, followed by the separation of the Briz-KM upper stage along with its cargo at an altitude of around 240 kilometers. Still short of an orbital velocity, the second stage was to reenter the atmosphere and fall into the Baffin Bay between Greenland and Canada.
The official Russian media, quoting Ministry of Defense officials, confirmed that the payload section had separated from the second stage of the launch vehicle as planned at 17:05 Moscow Time (14:05 GMT, 10:05 a.m. EDT).
Upper stage maneuvers
An approximate flight scenario of the Geo-IK-2 No. 12 mission during its first three orbits.
The Briz-KM was then expected to fire its engine to insert the stack into an initial elliptical (egg-shaped) orbit over Arctic Canada.
During this maneuver, the spacecraft likely left the range of Russian ground control stations and continued its mission according to its pre-programmed sequence.
Upon completion of the first burn, Briz-KM was to enter an unpowered climb for slightly more than one hour, interrupted only be short bursts of attitude control thrusters to put the stack into the desirable attitude.
When the vehicle reached the highest point (apogee) of its elliptical orbit over the Indian Ocean, Briz-KM was to fire its engine to make the orbit circular at an altitude of more than 1,000 kilometers above the Earth's surface. Minutes later, the space tug was likely programmed to orient itself for the separation of the satellite.
By that time, Briz-KM and Geo-IK-2 had to re-entered communications range of Russian ground stations, as the two vehicles were making their second revolution around the Earth. As a result, ground controllers from the Russian military could be able to monitor this critical phase of the mission in near-real time.
According to Zvezda TV, the spacecraft entered the contact with ground stations of the Titov Chief Test Center near Moscow 1 hour and 35 minutes after liftoff.
As expected, shortly after 19:00 Moscow Time on August 30, the official Russian media cited the Ministry of Defense as confirming the successful separation of the satellite into its planned orbit. According to the Russian military, ground control established reliable communications with the spacecfaft.
Due to the Earth's eastward rotation, the ground track of the second orbit shifted in the western direction, taking both vehicles from south to north across western part of Africa, the Mediterranean, Turkey, the Black Sea and Eastern Europe.
Around the time when Briz-KM was to cross the Baltic Sea, Scandinavia and then fly over the Arctic Ocean again, it was likely to begin maneuvering itself into a "burial" orbit at a safe distance from its former cargo. The Russian Ministry of Defense later confirmed the successful disposal of the upper stage in a 640 by 950-kilometer burial orbit.
The Joint Space Operations Center, JSpOC, of the US Strategic Command, reported two objects associated with the launch (most likely the Geo-IK-2 No. 13L satellite and the Briz-KM upper stage after it had completed its maneuvers to enter a burial orbit) with the following orbital parameters:
After the two-satellite Geo-IK-2 system is finally deployed and operational, it is expected to take from 2.5 to three years to accumulate a full set of data for the development of a global model of the Earth's shape.
ISS Reshetnev's documents also indicated plans for the launch of the new-generation Geo-RG satellite in 2018.
The Sadko altimeter for the Geo-IK-2 satellite. Click to enlarge. Credit: ISS Reshetnev
Rockot lifts off with Geo-IK-2 No. 13L satellite on August 30, 2019. Credit: Zvezda TV channel
Scences in firing control room in Plesetsk during the launch of the Rockot booster on August 30, 2019. Credit: Zvezda TV channel