Carbon isotope ratio measured in the atmosphere of planet Beta Pictoris b

Star system: Beta Pictoris | Distance from the Sun: 64 light years

Beta Pictoris b is a young, giant planet located in a star system where astronomers can directly image its atmosphere. By studying the specific chemical makeup of this world, researchers can learn how it formed and how its composition compares to the raw materials found in the gas cloud that birthed the system. This study provides a detailed chemical profile of the planet, focusing on carbon isotopes and its overall atmospheric makeup.

The planet was observed over 11 nights using the Very Large Telescope in Chile, which utilized a high-resolution instrument to break down the light coming from the planet into a spectrum. By analyzing these light signatures, specifically targeting the carbon-12 and carbon-13 isotopes, the researchers determined the ratio of these atoms in the planet's atmosphere. This data helps establish a benchmark for how similar giant planets form in the inner regions of their star systems.

In addition to the carbon ratio, the team measured the abundance of various elements and the ratio of carbon to oxygen. The findings show that the planet possesses a near-solar level of metals, along with a carbon-to-oxygen ratio that resembles that of our own Sun. The analysis also suggests the presence of thick clouds within the atmosphere of Beta Pictoris b. These results are consistent with the current makeup of the interstellar medium, the gas and dust that fills the space between stars.

Key findings
- The carbon isotope ratio in Beta Pictoris b matches the composition of the current interstellar medium.
- Atmospheric measurements reveal near-solar to mildly super-solar levels of heavy elements.
- The carbon-to-oxygen ratio is comparable to solar values.
- Evidence suggests the presence of thick, obscuring clouds in the planetary atmosphere.
- Observations establish a chemical benchmark for planets located interior to the carbon monoxide snow line.

Scientific study

The carbon isotope ratio of β Pic b with high-resolution spectroscopy (external link)