Joe BidenPresident of the United States, this week released the first image of the telescope James Webb from NASA. Thanks to the project, the result of a collaboration between the American institution, the European Space Agency and the Canadian Space Agency, it was possible to take the most distant and accurate snapshot ever obtained from the deep universe in the infrared spectrum.
“This image marks the beginning of a new era in astronomical observation. Expectations have been exceeded. We are about to enter a revolution in infrared astronomy“, assures Paul Arrabalan astrophysicist from Malaga in the international project, during an interview from Tucson (Arizona) where he does piecework for the US National Science Foundation.
The scientist, originally from El Palo, leads one of the largest telescope initiatives sent into space to learn up close how the first galaxies formed. “When we saw the first shots, we thought, ‘Everything is working as it should and we’re going to do a lot of amazing things with it.’ I am very excited. We have been preparing for this moment for a long time.“, recognize.
for Arrabal, “It’s just started.” Until now, the hardest part had been taken by the engineers and the people dedicated to the calibration part of the various instruments of the James Webb. “Now it’s the turn of astrophysicists. We’re going to do science with images,” he rejoices, saying that the James Webb “will go down in the history of astrophysics and humanity as did the Hubble Space Telescope and the Moon landing.”
The galaxy cluster SMAC 0723
The telescope has captured the most distant image ever of the deep universe in the infrared spectrum. It shows a cluster of galaxies 4.6 billion light-years from Earth called SMACS 0723.. “It is a very beautiful image. It’s even more beautiful when you know what it represents”, confides the scientist between two laughs before specifying that the James Webb “observes in the infrared of the electromagnetic spectrum, not in optics like Hubble.
According to Arrabal, “it is more difficult to obtain good resolution in the infrared and these are certainly better than those taken by Hubble”. The “spectacular and historic” image ands the product of 12.5 hours of exposure with the telescope. “Hubble took weeks to achieve the same thing. And with only 12 hours, it managed to see more things,” he points out.
“Relative size is like holding a grain of sand at arm’s length. These arcs seen here are the gravitational lensing of the central galaxy cluster. It has such a strong gravitational pull that it bends spacetime around it and this causes an effect called gravitational lensing. Light from objects billions of light-years behind the lens is distorted by the effect of the spacetime-distorting cluster.” Therefore, we see galaxies distorted and stretched, as if they were made of plasticine.
The James Webb successfully measured the temperature and detected water in the atmosphere of WASP-96b, a giant planet of 1,150 light years slightly larger than Jupiter and very hot (it’s more than 500 degrees centigrade). “It’s an exoplanet orbiting a Sun-like star. Basically, it’s a very large but very sparse planet. It’s half the mass of Jupiter and 1.2 times larger. Its star rotates very quickly, in three and a half days“, need.
“The spectrum is the distribution of energy in the wavelength of an object. You take the spectrum of the star and see how that spectrum varies as the planet passes through the orbit and produces a mini-eclipse . The effect of the planet’s atmosphere leaves an imprint on the star’s spectrum. So the spectrum is taken when the planet is separated from the star, and it is taken again when the planet is between the star and us. Light from the star passes through the planet’s atmosphere and marks its energy distribution.”
Webb scientists are able to measure this and see if these patterns match water vapor in the atmosphere. Indeed, observations have revealed that in the atmosphere of this gaseous planet there is water and clouds.. It is “a demonstration of the feasibility of finding this type of tracers in exoplanets with this telescope in a simple way”.“.
“We don’t expect there to be life. Now we can determine if there is water vapor in the atmosphere. Hopefully we will find it on other types of planets more likely to harbor life. We can show that there are conditions for life to exist. We do not say that there is life. There is a big jump,” he said.
The Carina Nebula
This image reveals for the first time regions of star birth that were previously invisible. It is a star-forming nebula, “an overdensity of hydrogen gas and dust where stars form; a cradle of stars“, specifies Arrabal. The advantage of James Webb when observing these types of objects in the infrared is that the dust is very transparent. “You get to see things that are eclipsed in the dust of the nebula . You see through that dust.”
The Carina Nebula is located 7,600 light years from Earth. “To give you an idea of the size, this is just one edge of the nebula. These columns of dust that you see here (on the blue background) are about seven light years long. The light takes seven years to travel from one point to the other of these columns. This mist that we see evaporating is an ionized gas. It is expelled out of the nebula by the radiation of the forming stars.”
South Ring Nebula
This one is, according to the astrophysicist, “all the more beautiful” as it is a planetary nebula. It is 2.5 billion light years from Earth.. “These are the last stages of a star that is already dying. This is the end that a star like the Sun is supposed to have. When the Sun ends its life, it will eventually die in the form of this nebula and a white dwarf in the center”, details.
“When you reach this final phase of your life, there comes a time when become a red giant and its atmosphere expands enormously. And after this phase, they begin to expel the outer layers of their atmosphere. You see different layers of gas from the star’s atmosphere that have been pushed out.”
Webb’s image quality will allow scientists to analyze the composition of each of the ancient layers of its atmosphere. “It gives you an idea of the evolution of the death of the star“, he underlines.
Among the curious details, Arrabal mentions that the central star is a binary system composed of two stars. “The two stars in the center of the nebula. Now there’s a greater ability to see through the dust. That was something that wasn’t possible with Hubble,” he insists. We can also see a singing galaxyThat is. “We see it perfectly in profile, so it looks like a line. It had never been seen before. A galaxy we had no idea about,” he says.
This huge mosaic is the largest Webb image to date showing a group of galaxies, and covers one-fifth the diameter of the Moon. It contains over 150 million pixels and is built from nearly 1,000 individual image files. “Although it’s called a quintet, in reality only four interact with each other. So said poetically it’s like a cosmic dance of galaxies. Two of them are merging into a single galaxy,” he explains.
In one of the galaxies, the James Webb is able to resolve a star cluster or a particularly bright star. “It is absolutely outrageous that we can resolve individual stars in galaxies that are not our own.“, recognizes the astrophysicist. From there, we can do a lot of research.
– What applications can these images have?
– The applications are endless. It depends on each person and what they do. These images touch all the sticks of astrophysics: stellar evolution, the death of stars, nebulae, exoplanets, which is a very fashionable subject, gravitational lenses and even the deep universes.
In the middle of the conversation, the scientist from Palencia clarifies that these images are “combinations of many different snapshots taken with different instruments which are then combined with color maps determined to give it this shape so that we can identify and get a visual idea of what this type of object looks like.” “These are measurements in the infrared. You would never see this if you were there. You would see its analogue in the visible. It’s the whole wavelength that humans can’t see,” he said.
A year and a half of “intense work” awaits Pablo. This Thursday they made public the data of the part of CEERS (Cosmic Evolution Early Release Science), an international project led by Professor Steven Finkelstein of the University of Texas at Austin where the native of Malaga plays a fundamental role.
It’s a deep-field map of a small region of the sky that contains a wealth of past data from observations with the Hubble Space Telescope. “CEERS uses three of the four instruments on board JWST (NIRCam, MIRI and NIRSpec). It will obtain both image and spectroscopy data, and is particularly interested in the study of very distant galaxies and their evolution throughout the history of the universe“, Explain.
It will be used by hundreds of scientists in the years to come to carry out all kinds of studies, including the discovery and characterization of the most distant galaxies ever seen, a few hundred million years after the Big Bang.