We’ve just added a new glossary on Spectroscopy and Spectral Lines. This page, a continual work in progress, will give an overview of how spectroscopy works and what spectral lines are frequently observed by astronomers.
Mergers play an important role in any galaxy’s evolution. A coincidental observation of a quasar and companion galaxy linked by a photoionized gas bridge offers an exclusive look at the merger process at moderate redshift.
Do close-in planets cause their host stars to become more magnetically active? Canto Martins et al. compare stars with and without planets to address this question.
Supernovae, the extremely luminous explosions that are the catastrophic deaths of stars, are used directly and indirectly by astronomers of many disciplines. Cosmologists use type Ia supernovae as powerful “standard candles” to probe the farthest rungs of the cosmic distance ladder. Astrochemists studying the interstellar medium (ISM) track supernovae feedback of heavier elements that enrich the ISM. Astrophysicists working on star formation look for evidence of supernovae-induced collapse of molecular clouds. If supernovae are such ubiquitous tools, then it must be essential to understand the actual supernova (SN) mechanism itself.
While theoreticians might work in many dimensions, observationalists must often do their analysis using very few. This paper presents observations of a classical nova from two types of spectrographs that determine a distance to the nova and a map of its morphology.
Assuming that we have acquired the spectrum of a distant terrestrial planet, what would it look like? Would we able to resolve surface features? More excitingly, would we be able to detect biomarkers in the atmospheres of alien Earths?