How much time, from first design to launch and operations, does an average Earth Observation satellite project take?

This is quite variable. When it comes to a complex Earth Observation mission, it can take up to a decade between the first investigations and the launch. This was the case for ENVISAT which is the largest Earth Observation satellite ever flown. ENVISAT is a satellite that carries 10 scientific instruments and weights 8000 kg. Smaller Earth Observation satellites, carrying an instrument already flown, can be developed in much shorter time, say a few years.

All about algorithms - what is your typical day like?

In short, my job is to provide algorithms that allow the exploiting of data generated by scientific instruments on board of ESA Earth Observation satellites. I find this most exciting. It implies digging into a scientific topic, understanding what the instrument measurements are made of, understanding how its measurements relate to a physical quantity in the Earth atmosphere, its oceans or its vegetation.

Sometimes, however, we neither have the in-house expertise ourselves nor the resources to fully develop such algorithms: we then commission the work to industry, laboratories or universities through a contract. This involves essentially the following tasks:

• We write down our needs in a Statement of Work and publish it on the web
• We then assess the technical and financial proposals we receive in response to it
• We follow the work being done by the winning consortium and ensure it is in line with our expectations. In the end this means a lot of managerial work.

It is, however, very important to me to find the right balance between hands on work and running contracts.

Depending on the project and its progress: How often and where do you need to travel to?

My interactions with other ESA centres in the Netherlands, Germany or Spain are limited. My working place is the European Space Research Institute (ESRIN), located nearby Rome. ESRIN is the ESA centre which is entirely dedicated to the exploitation of the Earth Observation satellites. There, I mainly give support to the office in charge of Earth Observation data quality and algorithm improvements. For each running project, I nevertheless need to travel. This happens about once per quarter, but increasingly I try to rely on videoconference tools. Up to now, I am normally off between 1 and 2 full months a year, cumulating all travels.

Do you physically check satellite instruments while they are being built?

My work involves modelling rather than building hardware. Building models, like building hardware generally requires me to interact with colleagues, industry, labs and universities. In order to develop a retrieval algorithm for a new instrument I need for example:

• to have the specification of the instruments
• to know the quantity which needs to be retrieved and with which accuracy and under which conditions
• to have the specifications of the system in which such an algorithm will be run.

I therefore need to interact with the ESA instrument engineer, the scientists who have proposed the mission and defined its scientific goals, and the ground segment engineer who will run the retrieval algorithm.

Which recommendations can you give to students or young graduates if they want to apply at ESA?

I would recommend to first check out on the ESA portal what it is that ESA does that most raises his or her interest: human spaceflight, Earth observation, space science, launchers… If there’s anything you fancy, look out for a Young Graduate Trainee position, or for an internship or check out which national trainee programmes there are. There are plenty of opportunities, good luck!