Astronomers have captured a rare moment in the cosmos: a newborn planet shaping spirals of dust and gas around a young star, 440 light-years from Earth. The discovery, made with the Very Large Telescope (VLT) in Chile’s Atacama Desert by the European Southern Observatory (ESO), occurred in the HD 135344B star system in the Scorpio constellation. Published on July 21, 2025, in the journal Astronomy & Astrophysics, the observation reveals an object about twice the mass of Jupiter actively sculpting the star’s protoplanetary disk. This unprecedented image offers critical clues about how planets, like those in our Solar System, form. The finding was obtained using the ERIS instrument, which detected a bright spot at the base of a spiral, confirming theories about planetary formation.
This observation marks a significant breakthrough in astronomy. Systems like HD 135344B, with protoplanetary disks, are natural laboratories for studying planet formation. The young star is surrounded by a disk of material that, under gravitational forces, begins to clump together, forming celestial bodies. The bright spot identified suggests a planet in formation, still accreting material.
- Key features of the HD 135344B system:
- Located 440 light-years away in the Scorpio constellation.
- Features a protoplanetary disk with spiral arms.
- The detected planet has an estimated mass twice that of Jupiter.
- Positioned at a distance from its star similar to Neptune’s from the Sun.
The study also examined another system, V960 Mon, over 5,000 light-years away, where a possible celestial companion was identified. These findings highlight the importance of high-resolution telescopes like the VLT in capturing rare cosmic events.
Technology behind the discovery
The Very Large Telescope, located in the Atacama Desert, is one of the world’s most advanced astronomical instruments. Equipped with the ERIS system, it enables high-resolution imaging capable of detecting faint objects in distant stellar systems. The bright spot in HD 135344B’s disk is not reflected starlight but light emitted by the planet or the hot material surrounding it, indicating active formation.
The ERIS, coupled with the VLT, uses adaptive optics to correct distortions caused by Earth’s atmosphere. This allows for sharp images of complex structures, such as the spiral arms of the protoplanetary disk. The discovery underscores the Atacama’s role as one of the best locations for astronomical observations due to its low humidity and clear skies.
- Advantages of the VLT and ERIS instrument:
- High resolution for capturing distant, faint objects.
- Adaptive optics for crisp images.
- Prime location in the Atacama Desert.
- Ability to detect light emitted by forming planets.
The work, led by Francesco Maio from the University of Florence, highlights the rarity of capturing a planet in formation. These events are brief on cosmic scales, lasting only a few million years, making them challenging to observe.
Planetary formation process
Planets form in protoplanetary disks made of dust and gas orbiting young stars. Under gravity’s influence, material begins to clump, forming planetesimals that grow into planets. In HD 135344B, the newborn planet is sculpting the disk, creating visible spiral arms.
This process is dynamic. The planet interacts with surrounding material, reorganizing dust and gas into spiral patterns. This gravitational interaction is direct evidence of its presence, confirming theoretical models. The object’s mass, about twice that of Jupiter, suggests it may be a gas giant, similar to the outer planets of our Solar System.
The discovery also raises questions about formation mechanisms. While the HD 135344B planet appears to grow through material accretion, the object in V960 Mon may have formed via gravitational instability, where a disk region collapses directly into a massive body.
Other systems under study
Beyond HD 135344B, the V960 Mon system, over 5,000 light-years away, revealed a possible celestial companion. Combined observations from the VLT and other instruments, like SPHERE and ALMA, showed spiral structures and gravitational instabilities in the disk, suggesting an object in formation. Its nature remains uncertain, possibly a planet or a brown dwarf.
- Features of the V960 Mon system:
- Located over 5,000 light-years from Earth.
- Protoplanetary disk with signs of gravitational instability.
- Possible presence of a planet or brown dwarf.
- Observed with multiple instruments for greater accuracy.
The differences between the two systems offer a unique opportunity to compare formation processes. While HD 135344B shows a planet actively shaping its disk, V960 Mon may indicate an alternative mechanism involving direct collapse. Future observations across different wavelengths will clarify these distinctions.
Significance for astronomy
Capturing a planet in formation is a milestone for understanding planetary systems. Earth, formed about 4.5 billion years ago, underwent similar processes, but we cannot observe them directly. Systems like HD 135344B and V960 Mon serve as windows into the cosmic past, enabling scientists to study conditions that led to habitable planets.
The discovery also underscores the potential of telescopes like the VLT and instruments like ERIS to advance astronomical knowledge. With increasingly precise technologies, scientists hope to capture more rare events, such as planet formation or the creation of complex stellar systems.
- Impacts of the discovery for science:
- Validation of theoretical models on planetary formation.
- New insights into the origins of gas giants.
- Advances in high-resolution telescope usage.
- Potential to study systems similar to our own.
Next steps in research
Scientists plan to continue observing HD 135344B and V960 Mon with advanced instruments like ALMA and the upcoming Extremely Large Telescope (ELT), also in Chile. These tools will enable more detailed analyses, particularly across different electromagnetic spectrum ranges, to confirm the nature of the detected objects.
The team also aims to better understand gravitational instability processes in V960 Mon. If confirmed, this finding could provide rare evidence of an alternative planetary formation mechanism, less common than gradual accretion.
The study emphasizes the importance of international collaborations in astronomy. Projects like those of the ESO, uniting scientists from various institutions, are crucial for advancing knowledge about the Universe.
Curiosities about forming planets
Observing newborn planets is a relatively new field in astronomy, driven by recent technological advances. Some interesting facts about the topic include:
- Gas giant planets, like the one in HD 135344B, can form in just a few million years.
- Protoplanetary disks vanish quickly, making it hard to capture planets in formation.
- The VLT’s adaptive optics correct up to 90% of atmospheric distortions for sharp images.
- Systems like HD 135344B may host multiple undetected planets.
These findings open new avenues for astronomical research, with potential to reveal more about the diversity of planetary systems in the Universe.