Spain celebrates its National Day with three new INTA satellites in orbit
Spain's National Day is celebrated on 12 October with a military parade in Madrid, when just over 72 hours ago the three satellites of the first Spanish space constellation were launched into orbit simultaneously.
The VV23 mission of the European launcher Vega lifted off from French Guiana in the early hours of 9 October at 03:36 Spanish time, two days later than planned. Vega has now fulfilled its space transportation task, unlike VV17 on 17 November 2020, when it exploded during its ascent and shattered the 830-kilogram Spanish Ingenio satellite and the 175-kilogram French Taranis satellite.
Fortunately, Vega has positioned nine different platforms and the first trio of nanosatellites from the Spanish National Institute for Aerospace Technology (INTA) in space three years later, "which occurred 1 hour and 44 minutes after liftoff," the institute confirmed. Constellation named ANSER, one of the three is the main platform and is known as the "leader". The other two are its followers, and are referred to as "follower 1" and "follower 2".
ANSER's main function is to demonstrate that they can fly in formation at a distance of less than 10 kilometres from each other, thereby extending their individual Earth observation capabilities. In terms of applications, once operational, they will be dedicated to monitoring the water quality of the marshes, reservoirs, lagoons and rivers of the Iberian Peninsula.
But perhaps the first thing the sensors on board the ANSERs will be able to observe is the 12 October parade through the centre of Madrid. INTA's director general, Air Lieutenant General Julio Ayuso, says that "everything is going according to plan. We are already receiving telemetry and we have contact with them. ANSER is the experimental mission that inaugurates the Institute's small satellite programme.
In the process of slowing down to lower its orbit
The INTA technicians at the Institute's main campus in Torrejón de Ardoz, near Madrid, confirm their "satisfaction because in the first pass of the satellites over the vertical of our antennas we have already picked up the signals emitted by each of them". The "leader" is responsible for communications with the ground, but any of the three can perform this task because "they have the capacity to transmit and receive data and telecommands".
The first actions being carried out in the mission monitoring and control room at the INTA Torrejón Space Centre (CEIT) are "braking". From "follower 2", to be followed by "follower 1" and "leader". "Now they are spinning around like spinning tops and the first thing to do is to stabilise them," confirms an expert who knows the ANSER project in detail.
In addition, Vega detached from the Spanish satellites a few seconds behind schedule. This means that they are several tens of kilometres above the altitude at which they should be operating, which is in the order of 500 kilometres.
As a result, INTA technicians have already begun work to bring them down from the current altitude of around 550 kilometres. This is not easy because none of the three, given their small dimensions - the size of a shoebox and weighing only 3.4 kilos - "are not equipped with even a small propulsion engine".
The descent of each of the ANSERs to its correct orbital position is carried out using a technique known as "differential lift and drag". "It consists of placing the larger surface of the satellite, a kind of wings that the three ANSERs have deployed in orbit, in the direction of flight. In this way they obtain an increase in drag in the upper layers of the atmosphere and, therefore, little by little, the satellite gradually loses altitude," explains the project's director, Santiago Rodríguez Bustabad.
They will be operational by the end of the year or the beginning of 2024
The monitoring and control of the satellites is carried out by a mixed team of INTA specialists and scientists made up of ten or so people, who supervise them 24 hours a day. Once they are stabilised, they will begin the manoeuvres that should culminate in placing and keeping them in formation and within 10 kilometres of each other and at an altitude of 500 kilometres.
Once the three ANSERs are at their correct working altitude, all the verification, adjustment and calibration operations - known as "Commissioning" - are expected to take "two to three months".
During this time, which will coincide with the end of the year or early 2024, all the equipment on board the ANSERs will be tested for proper operation. The observing subsystems will also be switched on, so that scientists can obtain the first data.
The initial users of the ANSER constellation are INTA scientists. As the mission progresses, the idea at the Institute is to distribute the acquired information to the scientific community through announcements of opportunity accessed by scientific groups.
The next satellite constellation that INTA is already working on is focused on providing data on air quality. It will include instruments to measure carbon dioxide (CO2), nitrogen dioxide (NO2) and ozone (O3).