This unprecedented observation was made possible thanks to the joint use of the James Webb space telescope and the Large Millimeter/Submillimeter Array (Alma). Scientists were able to observe the first signs of planetary training around the Hops-315 star, located 1,300 light years from Earth. This discovery, published in the journal Nature, marks a turning point in our understanding of the training of planetary systems and offers a unique window on the past of our own solar system.
A major advance in understanding planetary systems
This discovery marks a turning point in our understanding of the formation of planetary systems. Melissa McClure, professor at the University of Leiden in the Netherlands and the main author of the study, said: “For the first time, we have identified the earliest moment when the formation of a planet begins around a star other than our sun”. This observation was made possible thanks to the synergy between the James Webb and Alma space telescope, two peak instruments in astronomy.
The HOPS-315 star, a young star similar to our sun in its beginnings, is surrounded by a protoplanetary disc where astronomers observed the condensation of hot minerals, the first step towards the formation of planetsimals. These minerals, rich in silicon monoxide (SIO), condenses at high temperatures and are crucial for the formation of planets. Protoplanetary discs are common structures around young stars, but it is the first time that scientists have observed this condensation process in such a detailed way.
Protoplanetary discs are common structures around young stars, but it is the first time that scientists have observed this condensation process in such a detailed way. Previous observations focused mainly on more advanced discs, where the planets were already being training. On the other hand, the disc around Hops-315 offers an overview of the very first stages of this process, allowing astronomers to better understand how planetary systems are starting to form.
The importance of planetsimals in planetary training
Planesimals are the first solid structures to appear in a protoplanetary disc. These celestial bodies, the size of a kilometer, are the fundamental bricks which will give birth to the planets. In the HOPS-315 disc, astronomers observed the condensation of minerals rich in silicon monoxide (SIO), a crucial process for the formation of planetsimals. These minerals are formed at extreme temperatures and gradually aggregate to form larger bodies.
Merel Van ‘T Hoff, co-author of the study and professor at the University of Purdue (United States), compares these results to “a photo of the emerging solar system”, specifying that “we observe a system that resembles our solar system when it was starting to train”. Planetésimals are essential for the formation of planets, because they serve as nuclei around which matter accumulates to form larger bodies. Without these solid structures, the formation of planets as we know it would not be possible.
Planetésimals are essential for the formation of planets, because they serve as nuclei around which matter accumulates to form larger bodies. In our own solar system, planetsimals gave birth to telluric planets, such as the Earth and Mars, as well as to the nuclei of the giant planets, like Jupiter and Saturn. By studying the planetsimals around Hops-315, astronomers hope to better understand how these processes take place and how they can vary from one stellar system to another.
These images illustrate how hot gas condenses in solid minerals around the young star hops-315. The image of the left was taken with the Large Millimeter/Submillimer Array (Alma) Atacama, whose ESO is a partner. Two inserts show impressions of artist of silicon monoxide molecules condensing in solid silicates.
Source: ESO/L. Sidewalk/soul (eso/nonj/nrao)/m. McClure et al.
Lightening on our own story
This discovery offers a unique window on the past of our own solar system. The old meteorites found on earth contain minerals similar to those observed around Hops-315, allowing scientists to date the start of the formation of our solar system. These meteorites, rich in SIO, were formed at extreme temperatures and played a crucial role in the formation of planets. By studying these primordial rocks, scientists can go up time and understand the conditions that reigned in the emerging solar system.
Edwin Bergin, professor at the University of Michigan and co -author of the study, stresses that “this process has never been observed before in a protoplanetary disc, or nowhere else outside our solar system”. This unique observation allows astronomers to compare planetary training processes in different stellar systems and better understand the mechanisms that govern the formation of planets. By studying HOPS-315, scientists also hope to discover clues on the training of habitable planets and on the conditions necessary for the emergence of life.
By studying HOPS-315, scientists also hope to discover clues on the training of habitable planets and on the conditions necessary for the emergence of life. The formation of planets is a complex process which depends on many factors, in particular the composition of the protoplanetary disc, the temperature, the pressure and the presence of volatile materials. By better understanding these processes, astronomers can assess the probability of finding habitable planets around other stars and better targeting their extraterrestrial life research.
A new path for the study of the first stages of planetary training
The HOPS-315 disc is an excellent analog to study our own cosmic history. As Merel Van ‘T Hoff explains, “this system is one of the best we know to explore some of the processes that occurred in our solar system”. This system offers astronomers a new opportunity to study the first stages of planetary training, serving as a substitute for solar systems during training through the galaxy. By studying HOPS-315, scientists can test their theoretical models and refine their understanding of planetary training processes.
Elizabeth Humphreys, astronomer at ESO and manager of the European Alma program, said: “I was very impressed by this study, which reveals a very early stage of the training of planets. She suggests that Hops-315 can be used to understand how our own solar system has formed. This result highlights the combined power of JWST and Alma for the exploration of protoplanetary discs ”. The combination of these two instruments allows astronomers to observe the protoplanetary discs with an unprecedented resolution, revealing details which were previously inaccessible.
The combination of these two instruments allows astronomers to observe the protoplanetary discs with an unprecedented resolution, revealing details which were previously inaccessible. Future observations with the JWST and Alma, as well as with other peak telescopes, will allow scientists to continue to explore the mysteries of planetary formation and to better understand the origins of our solar system. This research also opens the way to new discoveries on exoplanets and distant stellar systems, expanding our understanding of the universe and our place in it.
Implications for astronomy and spatial research
This discovery has major implications for astronomy and space research. By better understanding planetary training processes, scientists can better assess the probability of finding habitable planets around other stars. This could also help target extraterrestrial life research and better understand the conditions necessary for the emergence of life.
In addition, this discovery highlights the importance of international collaboration in astronomy. Hops-315 observations were made possible thanks to the collaboration between several institutions and countries, pooling their resources and their expertise. This collaboration is essential to advance our understanding of the universe and to make major discoveries.
Finally, this discovery recalls the importance of continuing to invest in space research and the development of new astronomical instruments. Telescopes like JWST and Alma are essential tools to explore the universe and to make revolutionary discoveries. By continuing to invest in these technologies, we can hope to make new major discoveries and better understand the mysteries of the universe.
The next research steps
Astronomers plan to continue to observe HOPS-315 and other similar stellar systems to better understand the planetary training processes. They also hope to discover other systems under training, which would make it possible to compare processes and better understand the possible variations.
In addition, scientists plan to use other astronomical instruments, such as the Hubble space telescope and the future Nancy Grace Roman space telescope, to observe these systems with an even higher resolution. These observations will make it possible to better understand the details of the planetary training processes and to refine our theoretical models.
Finally, astronomers also hope to discover clues on the training of habitable planets and on the conditions necessary for the emergence of life. By studying stellar systems during training, they can better understand the processes that govern the training of planets and assess the probability of finding habitable planets around other stars.
