Exploring the Cosmic Dust Cycle

The intricate dance of metals between gas and dust in the neutral interstellar medium (ISM) is a crucial element in understanding the baryonic cycle of galaxies. Recent insights reveal how the variations in interstellar dust impact our ability to trace the chemical evolution of the universe across cosmic time.

Revolutionary Spectroscopy Paving the Way

Harnessing the power of multi-object ultraviolet (UV) spectroscopy with the Hubble Wide-Field Observatory (HWO) opens up new avenues for studying the abundance and properties of interstellar dust. By capturing extensive data on dust depletion and abundance, scientists can tackle significant questions surrounding chemical enrichment and the evolution of galaxies.

A Closer Look at Local Volume Galaxies

With medium-resolution spectroscopy operating at R~50,000 across the UV spectrum (from 950 to 3150 Angstroms), researchers can analyze massive stars in nearby galaxies, specifically those within 10 megaparsecs. This advanced technique allows for precise measurements of essential elements like iron, silicon, magnesium, sulfur, and zinc, enabling scientists to map how dust abundance shifts based on factors like metallicity and gas density.

The Challenge of Carbon and Oxygen Measurements

However, delving deeper into the dust’s carbon and oxygen content presents a challenge. Achieving high-resolution measurements (R > 100,000) and excellent signal-to-noise ratios (S/N > 100) is imperative because UV transitions for these elements are faint and non-saturated. Given that carbon and oxygen represent the largest metal mass reservoirs for dust in the neutral ISM, incorporating a grating design similar to the HST STIS H gratings is vital for the HWO. This will ensure high-resolution capabilities along with FUV and NUV detectors that can capture stunningly clear data.

Collaborative Efforts Driving Discovery

Astrophysicists like Julia Roman-Duval, Yumi Choi, and Mederic Boquien are leading the charge in this revolutionary exploration. Their combined expertise will serve as a guiding force in unraveling the complexities of interstellar dust and its role in the grand tapestry of the universe.