JWST and the Challenge of Stellar Noise

The James Webb Space Telescope (JWST) can detect incredibly small variations in transit depth, down to about 0.01%. This precision also means that signals previously hidden in noise must now be carefully analyzed. Starspots—cooler, darker patches on a star’s surface—can mimic or obscure real atmospheric features, making it crucial to understand their impact on observations.

Figure 1. Exoplanet with a Strikingly Tilted Orbit Leaves Astronomers Baffled.

The Peculiar TOI-3884 System

TOI-3884, a red dwarf about 140 light-years away, hosts TOI-3884b, a “super-Neptune” roughly six times Earth’s radius. Its transits consistently reveal a distinct spot-crossing feature, a rare occurrence that allows astronomers to study both the starspots and the system’s orbital dynamics simultaneously.

Previous studies (Almenara et al. 2022; Libby-Roberts et al. 2023) disagreed on key properties of the system, including the star’s rotation and inclination. The new research aims to resolve these uncertainties using higher-quality ground-based observations. Figure 1 shows Exoplanet with a Strikingly Tilted Orbit Leaves Astronomers Baffled.

JWST and the Challenge of Stellar Noise

The James Webb Space Telescope (JWST) can detect incredibly small variations in transit depth, down to about 0.01%. This precision also means that signals previously hidden in noise must now be carefully analyzed. Starspots—cooler, darker patches on a star’s surface—can mimic or obscure real atmospheric features, making it crucial to understand their impact on observations.

The Peculiar TOI-3884 System

TOI-3884, a red dwarf about 140 light-years away, hosts TOI-3884b, a “super-Neptune” roughly six times Earth’s radius. Its transits consistently reveal a distinct spot-crossing feature, a rare occurrence that allows astronomers to study both the starspots and the system’s orbital dynamics simultaneously.

Previous studies (Almenara et al. 2022; Libby-Roberts et al. 2023) disagreed on key properties of the system, including the star’s rotation and inclination. The new research aims to resolve these uncertainties using higher-quality ground-based observations.

Astronomers have identified an exoplanet whose orbit around its star is drastically tilted compared to the star’s equator. Such extreme orbital tilts are rare and challenge conventional models of planetary system formation.

Measuring the Tilt

Scientists determine orbital tilt using techniques like the Rossiter-McLaughlin effect, which observes changes in a star’s light as a planet transit across it. These precise measurements revealed that the planet’s path is far from aligned with the star’s rotation.

Why This Is Unexpected

Most planets form in a flattened disk around their star, naturally aligning their orbits with the star’s equator. A tilt this extreme suggests unusual events, such as gravitational interactions with other planets, nearby stars, or even past collisions.

Source: SciTECHDaily

Cite this article:

Priyadharshini S (2025), Astronomers Puzzled by Exoplanet with an Extremely Tilted Orbit, AnaTechMaz, pp.607