Direct images of exoplanets are rare. Future observatories might change that, but for now they don't tell researchers much. The planets are shown as blobs of light.

A new study shows that only a small amount of data can help us understand an exoplanet.

Astronomers can only image exoplanets in certain circumstances. The light from a star washes out the fainter light from other planets. Most exoplanets are far from their star, or very young. Young planets with high thermal output can be seen in IR, while the light from massive exoplanets or exoplanets far from their stars is washed out.

Direct images of exoplanets aren't clear or detailed. Exoplanets usually appear as indistinct blobs. Image Credit: Currie et al. 2022.
Direct images of exoplanets aren’t clear or detailed. Exoplanets usually appear as indistinct blobs, like in this image of AB Aurigae b. Image Credit: Currie et al. 2022.

One team of researchers were able to expand their understanding of planet formation by seeing the images of the exoplanet. Since most exoplanets are found by looking at transit light curves, any actual images of exoplanets are exciting. If the authors of a new study are correct, then even a small part of an exoplanet's surface can propel our understanding forward.

There is a new study available online at the pre-press site arxiv.org. The author is from the Astronomy Department at the University of Tokyo.

The study focuses on the future when it becomes feasible to image exoplanets. The images may only show a small part of the exoplanet's surface. How can we learn from a small amount of data? According to this study, more than you might think.

The team explains that the time series of light reflected from exoplanets can provide spatial information with respect to the planetary surface. Even when the data is sparse or weak,parse modelling can find predictions in the data.

The researchers used sparse modelling on a toy Earth. They found surface features useful in exoplanet study.

They wrote about prior knowledge of the planet's surface.