Stellar insights—the Mauve mission’s journey into the cosmos

In a quest to study the variety of stars in our galaxy, the Mauve mission has emerged to provide a stronger understanding of the characteristics of stars—including their magnetic activity, flare evolution, and influence on the habitability of neighboring exoplanets. Chuanfei Dong, an assistant professor of astronomy within Boston University’s College of Arts and Sciences, is the lead Principal Investigator (PI) at BU for the Mauve mission.

“Mauve” refers to the UV satellite provided by Blue Skies Space that scientists will utilize in a multi-year collaborative survey program, which is slated to commence mission operations in 2025. The satellite will be instrumental in providing scientists with a rare chance to re-examine and analyze active stars, which have been beyond reach since observations ceased as early as 2013 with the Galaxy Evolution Explorer (GALEX).

In this Q&A, Dr. Dong shares his insights on the mission’s objectives, technological innovations, and the potential implications for our understanding of stars and exoplanet habitability.

What inspired you to pursue research in your field, and how does your involvement in the Mauve mission align with your research interests? What aspect of the Mauve mission are you particularly excited for?

There is one eternal question in astronomy: Are we alone in the universe? There are so many stars in the sky, and based on current knowledge, there is at least one planet orbiting around each star, and most likely, several. So, our Earth is not unique. If we want to find a second Earth, we need to understand if they are habitable. The Mauve mission will provide a greater understanding of how stars and their activity may impact the habitability of neighboring exoplanets, which I am particularly excited about.

How will the mission’s ultraviolet spectroscopy enhance our understanding of stars’ magnetic activity?

Ultraviolet spectra often contain prominent emission lines that are sensitive to the presence and strength of magnetic fields. By studying these lines, astronomers can infer properties of the magnetic fields in stars. Magnetic activity, such as flares and coronal mass ejections, can be detected through their UV emissions.

What techniques or instruments will be used aboard Mauve to observe and analyze stars in the UV spectrum?

• Ultraviolet imaging: Mauve would use UV-sensitive detectors to capture images of stars in the ultraviolet range. These images would provide valuable information about the surface features, temperature variations, and overall structure of stars in the UV.
• Ultraviolet spectroscopy: Spectroscopic analysis of stars in the UV spectrum would be crucial for understanding their physical properties and processes. Mauve would use UV spectrographs to disperse starlight into its component wavelengths, revealing absorption lines, emission lines, and other spectral features that can provide insights into the stars’ composition, temperature, and magnetic activity.
• Time-Domain observations: Mauve could conduct time-domain observations of stars in the UV spectrum, monitoring changes in their UV emissions over time. This approach would enable the study of transient phenomena such as stellar flares, variability in magnetic activity, and periodic processes like stellar rotation and activity cycles.

Are there any specific types of stars or stellar phenomena that the Mauve mission aims to prioritize in its observations?

Mauve will prioritize in its observations for the M-type stars, which are magnetically much more active than the sun. Mauve will be used to observe stellar flares from M-type stars. In addition, Mauve’s wide wavelength range is not only sensitive to photochemistry and magnetic heating processes in NUV of neighboring exoplanets, but also covers the entire UVC, UVB, and UVA regimes (200–400 nm) which would act as empirical, indispensable data for assessing exoplanet habitability.

How will Mauve’s observations complement or build upon existing ground-based and space-based telescopes studying stars in different wavelengths?

First, ground-based telescopes cannot observe UV wavelengths due to the existence of Earth’s atmosphere (Earth’s atmosphere absorbs most UV radiation). Second, although telescopes like Hubble can observe UV wavelengths, they are not dedicated to observing stellar magnetic activity.

Thousands of Mauve’s observational hours will be dedicated to each year of the survey, with many stars continuously available within Mauve’s wide field of regard, enabling long baseline observations and unlocking a significant time domain astronomy opportunity. Mauve will significantly increase the availability of UV spectra, providing a rare opportunity to revisit bright, active stars inaccessible previously.

How will the mission address potential challenges or limitations associated with observing active stars, such as variability in their activity levels or contamination?

Mauve could conduct long-term monitoring campaigns to track the activity levels of stars over extended periods. By observing stars regularly over weeks, months, or even years, the mission can identify trends, periodicities, and anomalies in their activity patterns.

Meanwhile, statistical methods can help separate intrinsic variability in stellar activity from instrumental noise or contamination. By analyzing large samples of stars with similar characteristics, Mauve can statistically infer the underlying properties of stellar activity and minimize the impact of individual outliers.

How does the Mauve mission plan to engage with the broader scientific community and share its discoveries and data?

Mauve’s survey science program will be decided by its members and is open to any scientist worldwide. Scientists and research organizations can access the survey program via an annual membership plan tailored to suit the needs of individuals, groups, and institutions. The survey actively encourages the involvement of Ph.D. students and early career scientists.

Originally appeared here.