One of the most notable examples of a planetary nebula, the Ring Nebula, had unprecedented images, with a quality never seen before, released at the beginning of the month by an international team of astronomers. Among them is Isabel Aleman, the only Brazilian in the group who can help understand the life cycles of stars and the elements they release into the cosmos. She is a researcher trained at USP, Bachelor of Physics from the Institute of Physics (IF) and Master and Doctor of Science from the Institute of Astronomy, Geophysics and Atmospheric Sciences (IAG).
Isabel is part of the JWST Ring Nebula Project team, which uses the most powerful space telescope today, the James Webb (JWST), launched into space on December 25, 2021 by the National Aeronautics and Space Administration (NASA) of the United States, in collaboration with the European Space Agency (ESA) and the Canadian Space Agency (CSA). James Webb is 100 times more sensitive than its
predecessor, Hubble, and one of the most complex projects NASA has ever developed.
“I have contributed since the beginning of the project, when the observation proposal was made. To
observe with James Webb, we submitted a project within the first regular call for observation proposals.
The project is evaluated by a team of specialists and may or may not be approved. The call is very
competitive, as there are many excellent projects entered and only a small fraction is selected, limited by the time available”, says Isabel, who is a member of the Organizational Committee of the H3 Planetary
Nebulae Commission of the International Astronomical Union.
She specializes in Astrophysics, with emphasis on the study of physics and chemistry of photoionized
nebulae, working mainly with computational simulations of emission in atomic and molecular lines of
nebulae and with the analysis of spectroscopic observations in the optical, infrared and submillimeter
ranges of the radiative spectrum.
The team that has Isabel as a member captured images of the Ring Nebula, also known as Messier 57,
formed by the colorful remains of stars that released a large part of their mass at the end of their lives.
The images were released in unprecedented detail, providing scientists and the public with an
unprecedented view of the nebula. The scientists, led by Professor Mike Barlow of University College
London (UCL), UK, believe that the images captured by JWST offer an unrivaled opportunity to study and understand the complex processes that shaped this “cosmic masterpiece”.
Brazilian participation
In the project, Isabel is contributing with the analysis of spectroscopy data. “In spectroscopy, the
instrument that the JWST has decomposes light, in this case infrared, and allows the study of how the
amount of this light varies in each frequency. With this we can discover which chemical species exist in
the nebula and in what quantity, as well as the physical conditions (temperature, density, degree of
ionization) in different regions of this object”, she informs.
Astrophysics also reports that, “with this information and with the help of models, it is possible, for
example, to study the physical and chemical mechanisms that occur there and produce this emission that
we observe, reconstruct its three-dimensional structure and infer the characteristics of the star that
ejected its material forming this nebula.” Isabel also explains that a planetary nebula is formed by the gas ejected by stars with a mass less than approximately eight solar masses. “The Sun, several billion years from now, will become a planetary nebula.”
The researcher is part of two other approved projects, in addition to having helped to lead the
international collaboration that analyzed one of the first images released by James Webb, which resulted
in an article published in the journal Nature Astronomy at the end of last year . “In this article, we studied another nebula with a ring morphology”, she says, adding that the name is similar, but it is a different nebula.
For her, working on the JWST Ring Nebula Project helps to show that Brazil has high-level
astrophysicists, working within projects on the most advanced topics and instruments in the area. “Our
astronomy is well inserted in the international community of researchers in the area”, she points out.
The James Webb Telescope – Photo: Razorien Eve/ Flickr
“It is also important to note, since we are talking about one of the STEM careers (Science, Technology,
Engineering and Mathematics, or Science, Technology, Engineering and Mathematics, in Portuguese),
that a good fraction of these researchers are women who work with a lot of success in astronomy”, she
points out, noting that her collaboration arose as a result of a workshop, in 2019, which she organized,
WorkPlaNS II: Workshop for Planetary Nebula observations , held in the Netherlands, which brought together specialists in the field of planetary nebulae and the like to plan observations and seek to resolve
the most important issues in the area. “That is, not only do we participate in excellent projects, we also
help to promote them.”
Unpublished images
“We are blown away by the detail in the images, better than ever. We always knew that planetary nebulae
were beautiful. What we see now is spectacular,” said Albert Zijlstra, Professor of Astrophysics at the
University of Manchester, in university outreach material.
Barlow, lead scientist for the JWST Ring Nebula Project , added: “The James Webb Space Telescope has
provided us with an extraordinary view of the Ring Nebula that we have never seen before. The high-
resolution images not only show the intricate details of the nebula’s expanding envelope, but also reveal
the inner region around the central white dwarf with exquisite clarity. We can use the Ring Nebula as our
laboratory to study how planetary nebulae form and evolve.”
For Brian Cox, co-scientist on the project, these images have more than just aesthetic appeal, “they
provide a wealth of scientific insights into stellar evolution processes.” According to him, studying the
Ring Nebula with the James Webb supertelescope will allow a deeper understanding of the life cycles of
stars and the elements they release into the cosmos.