We thought before that we knew all about the solar system, but as we discover other systems around different stars, we found that our original model did not fit with that. The more science that we do, the more challenges to ideas that we have to add to the important debate.
Alvaro Giménez Cañete, Director of Science and Robotic Exploration at the European Space Agency, highlights the continent's role in ongoing space exploration...
Alvaro Giménez Cañete
You may ask yourself, is there a future for European space exploration? And I can tell you certainly: Yes. There has to be a future. We cannot escape exploration – it's in our genes, because we look at the sky and we are looking for what is around us, what the position of Earth is in the solar system and the universe. We have big questions that humankind has to answer about our position in the universe, the origin of it, the origin of life and why human beings are here. These are the kinds of things we want to know, and that is part of understanding what is around us, what nature is and how our life is influenced by these surroundings. This is exploration, and we have been doing it for centuries, of course around our planet, but now we have the opportunity to explore beyond our planet, and that's what we call space exploration.
It is a challenge for human curiosity – we are curious about what is there and we want to see what is around us. Exploration may be driven by different factors, and normally it is a mixture of such factors. Science is increasing knowledge – we want to be somewhere, but as soon as we get there, we want to understand why it is the way that it is and not as it was on our side of the world. By gaining understanding of why things are the way they are, we are doing science. We also find opportunities for economy, for developing technologies, and for having more tools to benefit society.
There is also a very important political aspect to promote global cooperation. There are challenges that we can only afford by working together. By that, exploration is not only something that individual member states cannot do by themselves, but even all European countries together cannot do all possible exploration. We have to work together on this planet to do space exploration.
We need to inspire new generations. Exploration, science and technology are something that we need in our society, and this is attractive for young people – they want to be explorers, they want to have the knowledge to be able to do it, and this attracts the brightest minds into something that we need. In particular, in Europe, we need this generation of scientists and engineers.
Society has to do exploration, but exploration also has benefits for science and applications that go back into society. Exploration is essential in answering questions that cannot be answered by an astronomer, a planetary scientist, a biologist or a chemist by themselves. We have to bring all these people together to talk to each other. They have to do cross-disciplinary science, to answer questions about the discoveries that are made. These questions are organised by different themes or topics. Exploration is a paradigm of synergies between science and technology, where we see the benefit of both working together. Exploration enhances the transfer of knowledge to applications for the benefit of society.
But where do we go? What do we have to explore? We have explored our planet, although there are still missing parts, such as deep oceans. Beyond Earth, there are three main destinations for us. The first, which should not be forgotten, is lower Earth orbit, where the International Space Station is. Lower Earth orbit is an essential environment to explore in terms of radiation, micro-gravity and essentially the effects on humans for space exploration in the future.
Then, we have the moon. The moon could be considered a natural space station that provides a platform for space exploration, and it is also scientifically important, as an archive of a near-Earth solar system.
Thirdly, there is Mars. It is the most attractive, and is why we are focusing our attention on it for human and robotic exploration. It is the closest environment to our own – we can see that in the pictures and such – so now we need to look at how we go there with astronauts. For the time being, what we are doing is the closest you can get to us really being there. The robots try to simulate with cameras and so on what we would do if we were there. This is the first step.
In robotic exploration, we of course want to prepare for human exploration. We have to understand the soil and the surface of the planet. We want to understand the atmosphere and the interior of the planet and what is below the surface. We also want to return samples, because we cannot take all of the sophisticated laboratories to Mars that we have on Earth. So, it's sometimes easier and cheaper actually, to bring samples back, to analyse them in detail.
We look for indications of what we think are typical for life in the present, or in the past at some point, but also we want to do research on how to use resources for human exploration. When we were explorers on Earth, we went to places and were confident that wherever we were going, we could get the resources needed to survive – food, water, air – which is not the case on Mars. Whenever we do anything outside of planet Earth, we have to take everything with us – the food, water and air we breathe. This is not very easy and it is expensive. So, we are looking into ways, ongoing projects, on how to do that and develope the resources we need.
The other point I want to highlight is that of cooperation. International cooperation is essential, but Europe's position is very important. We have a history and a heritage in exploration, so we have to have a visible role in global exploration. For that, we have to prepare our skills and capabilities to be key partners. We don't want to just be the ones paying for a ticket to go with somebody else. We want to be part of it all, and for that we need to have the knowledge, the skills and the capabilities to be part of the future of global exploration. This is the goal of ESA space exploration: to prepare and develop Europe as an essential partner.
So, what are we doing now? This is exploration now: we are going to planets around us with science-driven missions. We have already given a good resource – we have the Mars Express mission, which has given excellent science results. We have taken pictures from orbit around Mars and information about the atmosphere and the surface in very good detail. We have even studied the satellites of Mars, which are an important element in understanding the formation of the solar system.
We have also looked at the satellites around Venus. Venus is a completely different atmosphere and not so close to what Earth is like; and whereas Mars is smaller, Venus is more or less the same size and mass as Earth in terms of size but it has a very thick atmosphere and the temperature below that atmosphere is very high – around 400 degrees centigrade, which is not comfortable for human life. We can look at differences in how they developed, with planets close to us having a completely different kind of evolution.
We do have other forms of exploration. One of the best achievements has been landing on Titan, the largest moon of Saturn. This is the furthest landing from Earth done by human beings, so this was a considerable challenge and a real success of the ESA in cooperation with NASA.
We then have the Rosetta mission, launched in 2004, which is going to study – and hopefully land on – a comet. It is due to reach the comet in 2014, so there is only a little time now to wait. It includes a lander, and a probe that will attach to the comet and analyse it directly and look at the conditions there. This will be the first time that we have done that. This is another key to looking at the origins, formation and evolution of the solar system.
We thought before that we knew all about the solar system, but as we discover other systems around different stars, we found that our original model did not fit with that. The more science that we do, the more challenges to ideas that we have to add to the important debate. There should be very good information to add to that from Rosetta. We have yet another mission that has not been launched yet, but will be very soon going to Mercury.
So, we have gone to Mars, Venus and soon Mercury. We have landed on Titan and we are going to a comet, and we had the mission to the moon. All of these are rocky objects around us, except Mercury – which is why we are going to Mercury, which is an astonishing object actually. Mercury is a planet closer to the sun, so it is peculiar in several aspects, in terms of mass, distribution and so on. And we don't know why that is – why Mercury is that way. So, it will give us measurements and ideas about what happens in the formation of the solar system if you are too close to the star.
This is not the end of it. We are currently in the process of a mission to another large moon, a satellite of Jupiter, which is particularly interesting because it is an icy moon. Icy moons around large planets, we think, could give us a good example of the type of planets that we are looking for in exosolar planets around other stars that may have a crust and oceans. These oceans could harbour some form of life. This is something that we are very interested in at this time.
But returning to one of the most interesting missions – the Mars Express – this is somewhere we feel a little at home, a dry, solid home, and although like a desert, it has some appealing aspects. Mars has a very interesting history and some stories to tell. We think that in the past it had a large watery mass, then there was a climate change and this water was lost. Water is a key solvent for certain molecules to develop and, eventually, sustain life.
This article, which was based by a speech delivered at ESOF 2012, originally appeared on Publicservice.co.uk: Another giant leap