The first Spanish constellation of spacecraft is to be dedicated to measuring the quality of water in reservoirs and marshes

European launcher Vega returns to space with three INTA ANSER satellites

PHOTO/INTA - Cada uno de los tres nanosatélites ANSER está fabricado en el estándar CubeSat 3U, tiene un peso de 3,4 kilos y es del tamaño aproximado de una larga caja de zapatos
PHOTO/INTA - Each of the three ANSER nanosatellites is made in the CubeSat 3U standard, weighs 3.4 kilograms and is about the size of a long shoebox

The staff of the National Institute for Aerospace Technology (INTA), which since May 2022 has been directed by Air Lieutenant General Julio Ayuso, is expectant about the imminent return of the European launcher Vega to flight. It will take off from French Guiana and is scheduled for Saturday, 7 October, at 03:36 in the morning, Spanish peninsular time.  

The success of the take-off of the European Space Agency's (ESA) Vega Flight number 23 (VV23) depends on the successful launch of three Spanish satellites, christened ANSER, which the Institute's engineers and technicians have made a reality. The constellation has been baptised with the name of the wild geese in Latin -anser-, whose flight resembles in a certain way the flight that the Institute's trio of small satellites will describe.


ANSER - an acronym for Advanced Nanosatellite Systems for Earth Observation Research - is a demonstration project consisting of three observation nanosatellites that, "functioning as a single integrated platform, will monitor the water quality of the marshes and reservoirs of the Iberian Peninsula," says Santiago Rodríguez Bustabad, head of the project. 

PHOTO/ESA-CNES-Arianespace-CSG-S. Martin - En la parte alta del lanzador europeo Vega del vuelo VV23 viajan una docena de satélites. En la parte inferior izquierda se aprecia la silueta de un ganso, las letras ANSER y el logotipo del INTA
PHOTO/ESA-CNES-Arianespace-CSG-S. Martin - On top of the European Vega launcher of flight VV23 are a dozen satellites. On the lower left is the silhouette of a goose, the letters ANSER and the INTA logo

Built to the CubeSat standard, each with a take-off weight of 3.4 kilos and the size of a shoebox, their main peculiarity is that they are designed to fly in formation between 400 and 500 kilometres above the Earth, in other words, "they must remain synchronised and keep a distance between them of around 10 kilometres," stresses Lieutenant General Julio Ayuso. 

Each one fulfils a different mission and, "as in the flight of the geese, there is one that has been configured to be the captain of the group," explains Ángel Moratilla, head of the Institute's Space Department. "The main satellite, called the "leader", is in charge of communicating with Earth and coordinating and managing the activities of the other two, called "followers". 

PHOTO/INTA - El director general del INTA, el teniente general Julio Ayuso, con el máximo responsable del departamento de Espacio, Ángel Moratilla y el director del Instituto Astrofísica de Canarias, Rafael Rebolo (izquierda) en una reunión en junio
PHOTO/INTA - The Director General of INTA, Lieutenant General Julio Ayuso, with the head of the Space Department, Ángel Moratilla and the Director of the Instituto Astrofísica de Canarias, Rafael Rebolo (left) at a meeting in June

An innovative constellation

The three must therefore be interconnected to demonstrate that it is possible to split up the formation control system and the different equipment on board the trio of satellites. 

Why put a trio of small spacecraft in space? The main technological objective of the mission is to achieve a high level of flight coordination capability. But the mission's main function is environmental. "It carries sensors, high-resolution mini-cameras and other technologies to determine the different levels of contamination of inland waters". 

The engineers and technicians involved in the project have had to face different challenges. One of them has been to miniaturise all the equipment and subsystems, especially the hyperspectral camera. The Cinclus spectrometer must detect and measure the quantities of chlorophyll and phycocyanin in inland waters to determine their degree of quality.

PHOTO/INTA - Los tres nanosatélites de observación van a funcionar integrados como si se tratara de una sola plataforma, para supervisar la calidad de las aguas de los pantanos y embalses de la península
PHOTO/INTA - The three observation nanosatellites will operate as a single platform to monitor the water quality of the peninsula's marshes and reservoirs

This is achieved "from the low energy reflected by the water, so our constellation will complement and extend the measurements made in the field," says Rodríguez Bustabad, head of the Engineering, Integration and Validation area of INTA's sub-directorate general for Space Systems, headed by Ángel Moratilla.

With the approval of the then director general of the Institute, Air Lieutenant General José María Salom, the origin of the project dates back to 2017. The initial funding came from the Institute. But it has since been expanded with grants from the European Union's In-Orbit Demonstration/Validation programme, which seeks to accelerate the development of innovative technologies for space, and from ESA, whose final contribution is the launch into space.

PHOTO/ESA-CNES-Arianespace-CSG-S.Martin - Momento en que cuatro dispensadores de nanosatélites son integrados en el sistema encargado de soltarlos en el espacio. En una pegatina se lee “Anser leader” y “Anser Follower 1 y 2”
PHOTO/ESA-CNES-Arianespace-CSG-S.Martin - Four nanosatellite dispensers are integrated into the system responsible for releasing them into space. A sticker reads "Anser leader" and "Anser Follower 1 and 2"

Accompanied by nine other satellites

The operational lifetime of the ANSERs is estimated to be "between two and three years", says Moratilla, as "they have no propulsion system and their on-board equipment will degrade due to the effects of cosmic radiation". And when they are decommissioned, "they will not generate any space debris," he stresses, "because they will re-enter the Earth's atmosphere, burn up and self-destruct".  

If the in-orbit project develops as planned, once the operational life of the constellation is over, it would be desirable to place new ones in orbit to provide continuity to the measurements. INTA is already working towards the 2025 horizon on the ANSER-AT mission, which includes sensors to measure carbon dioxide and other greenhouse gases that contribute to increasing the Earth's temperature.

PHOTO/INTA - Los ingenieros y técnicos que han participado en el proyecto han tenido que afrontar diferentes retos. En especial, miniaturizar la cámara hiper-espectral Cinclus que debe medir las cantidades de clorofila y ficocianina de las aguas
PHOTO/INTA - The engineers and technicians involved in the project have had to face several challenges. In particular, they had to miniaturise the hyper-spectral Cinclus camera, which has to measure the quantities of chlorophyll and phycocyanin in the water

INTA's three nanosatellites are accompanied by nine other spacecraft. The heaviest and largest are Thailand's Theos-2, a 425-kilogram high-resolution Earth observation platform, and Taiwan's 280-kilogram Formasat-7R/Triton. With them are seven other very small satellites, similar to the ANSERs, from Estonia (EstCube-2), France (N3SS), ESA and several other institutions. 

The ANSERs will be flying in space 10 years after the previous INTA satellite, Optos. It was a tiny technological demonstrator, similar in size and weight to one of the ANSERs now to be launched.

PHOTO/INTA - Parte del equipo del director del proyecto, Santiago Rodríguez Bustabad, que han dado vida a los tres nano satélites de demostración ANSER, la primera constelación del INTA
PHOTO/INTA - Part of the team of the project director, Santiago Rodríguez Bustabad, who have given life to the three ANSER demonstration nano-satellites, INTA's first constellation

Also built by INTA to the CubeSat standard, Optos was launched into orbit on 21 November 2013 by a Russian Dnepr-1 rocket to measure the Earth's magnetic field and evaluate a tiny low-resolution camera. It is out of service and in the process of atmospheric descent, which means that it will self-destruct due to friction with the layers of the Earth's atmosphere.