Noemí Pinilla-Alonso: The Spanish astronomer is about to explore the vastest and most mysterious expanses of the solar system | United States
A native of Oviedo, in the northern region of Asturias, Noemí Pinilla-Alonso says that as a child it was difficult to gaze at the stars because the weather was almost always cloudy. However, every summer his family traveled to Toro, Zamora, where his parents, a salesman and teacher, grew up. There, the “sky of Castile” allowed him to discover his first constellations.
The little girl is now 50, and as an astronomer at the University of Central Florida’s Space Institute, she’s leading one of the most ambitious investigations into the far reaches of our solar system to date; Using the James Webb Space Telescope, she and her team will explore what lies beyond Neptune, the last planet in our solar system.
Pinilla-Alonso’s life has been forever turned upside down by one of the greatest astronomical controversies of this century: the discovery of a number of distant bodies larger than the dwarf planet Pluto which has led to intense international debate.
For the first time, the largest space telescope in history will be able to peer into some of these bodies – namely Eris, Make Make and Haumea – and see if they have the basic ingredients for life. Thanks to the Webb telescope, Pinilla-Alonso will also be able to explore the unknown moons of Uranus: Ariel, Umbriel, Titania and Oberon. But the goal of his company is to study the transneptunian bodies, a vast ring of millions of unknown objects that extends beyond the planet Neptune.
Question. Why go beyond Neptune?
Responnse. Transneptunian objects form one of the largest but least known structures in the solar system. We are aware that this belt of icy objects beyond Neptune is where comets emerge. We know that this belt contains large objects like Pluto, about 2,000 kilometers in diameter, and smaller ones, less than 10 kilometers. There may be trillions of them, although so far we only know of 3,000. We have no idea what their surface is like. Water has been detected, but we do not know how much there is. It is also not known whether this is the most abundant element or if there is also ice made up of methane, methanol, nitrogen or carbon dioxide. And this is very important because they are the seeds of life.
Q. Can life on Earth have its origin in these bodies?
A. It’s true. In comets, ice is transformed into gas and dust. That’s why we know they contain compounds like methanol and carbon monoxide, which are key building blocks for life. During the most chaotic times in the solar system, there was an echo between Jupiter and Saturn. Each revolved around the Sun in their own way, but at some point they became gravitationally connected and moved in a coordinated fashion. These are the two larger planets and they started to move in unison, sweeping all around them and ejecting smaller bodies, like a huge billiard ball. Many of these bodies were sent either into the solar system or out. At that time, there were many, many collisions with the Moon and the Earth. And maybe that was when ice water and organic compounds hit our planet and we had the very beginnings of life. These two giant planets also caused the migration of Uranus and Neptune to the far reaches of the solar system. And they, in turn, swept the outer areas. It is believed that in their original state, all Transneptunian objects were 10 times the size of Earth. But most of them have disappeared. Now there is only about 10% left. What we want to know are the details of what happened.
Q. Why is the James Webb Telescope so important for the study of these objects?
A. As cliché as it sounds, there are a lot of unanswered questions when it comes to our knowledge of the solar system. For example, we don’t fully understand how it formed, or much of it on the planetesimals – the fragments that could come together to form the planets. Theories which attempt to explain it only partially succeed. The James Webb is a large space telescope that can observe the infrared universe. This means that it will reveal a universe that has been hidden so far. On the subject of transneptunian objects, he will show us the materials that compose them. This will allow us to examine the processes that have affected them from their formation billions of years ago to the present day.
We are much more blind to dangerous asteroids since the dismantling of the Arecibo telescope
Q. Couldn’t we do it with telescopes on the ground?
A. Since the first transneptunian object besides Pluto was discovered in 1992, many more of these bodies have been detected. Seen from Earth they are not very bright and the data we can get with ground telescopes is limited. Recently, we have discovered that there are not only larger bodies, but also smaller and more dimmer bodies in which water is mixed with other materials. But it is impossible to identify these materials from the ground. We’re assuming the very red ones have complex organic compounds – those key compounds for life – but we need to confirm that and we can do that with Webb.
Q. What objects are you going to focus on?
A. NASA’s New Horizons probe showed us the surface of Pluto in detail. He showed that this dwarf planet has an atmosphere and that there is a transfer of matter to the surface. We know the extent of its glaciers, craters and ice deposits. Conversely, other even larger objects are largely unknown. We now have almost 100 hours of guaranteed time with Webb to observe the greatest transneptunians: Eris, Make Make and Haumea, as well as Pluto and Charon.
Q. Will you be able to expand what we know about smaller bodies?
A. Yes, we have another project for that. With the few transneptunians seen so far, we know there is great diversity – objects as dark as asteroids that must be made of carbon and others as bright as freshly fallen snow, like Haumea. To know what is in this belt, you have to study very different objects; we will study 60 of them.
Q. Could these studies reveal the existence of a new planet on the fringes of our solar system?
A. At present, there are two approaches to this planet X. One group continues to study the more distant Transneptunians to see if their orbits are aligned and are influenced by this distant planet while another group thinks they are. There is no such alignment and that many other objects have to be discovered and observed in order to explore their behavior. The James Webb Telescope is not the right tool for researching or discovering planets in our solar system because it has a limited field of view. However, it would be the perfect tool to study its surface if another telescope, like the Vera Rubin Telescope, which will scan the entire sky in the next decade, found out.
Q. You were principal investigator at Arecibo, the largest radio telescope in the world, now dismantled. Is there a way to get it back?
It’s hard to imagine that there is no life beyond Earth
A. This observatory is unique in the history of science. Not only was it the largest radio telescope in the world, it was also very versatile. Its original antenna was supplemented by many others which made it the most powerful tool not only in radio astronomy, but also in the study of our own atmosphere, the ionosphere, and as a huge radar to support the NASA’s planetary coordination defense office. The censuses discovered potentially dangerous asteroids and Arecibo pointed its radar and allowed us to calculate their orbit with great precision. We knew if they were dangerous and when the next ones would arrive on our planet.
Q. So, are we a little more blind now to dangerous asteroids?
A. We have become much more blind. Right now we pretty much only have NASA’s Goldstone antenna, which is much smaller. We can only identify the largest and closest objects. All the asteroids that could catastrophically destroy Earth are already mapped, but there are plenty more that could destroy entire cities that are not.
Q. Do you believe there is life beyond Earth? If so, where are we most likely to find it?
A. There is no proof, but it’s hard to imagine that there isn’t. There are so many stars, so many galaxies, that there must be life in some of them. The question is whether we are able to find out. That is why we must continue to collect data, observe and invest in finding signs that we believe are the origin of life on Earth. We have to find discs with materials similar to ours. There is also the Technological Traces Project, which is based on tracking the universe to see if we receive a signal, emitted by a possible civilization.
Q. Do you believe that such signals exist?
A. It’s interesting. We cannot ignore the possibility.