String of Life

A Starbirth Filament in Submillimeter Wavelengths

This image from the APEX telescope, of part of the Taurus Molecular Cloud, shows a sinuous filament of cosmic dust more than ten light-years long. In it, newborn stars are hidden, and dense clouds of gas are on the verge of collapsing to form yet more stars. This image is a composite of visible-light stars and the LABOCA submillimeter data. ESO/APEX (MPIfR/ESO/OSO)/A. Hacar et al./Digitized Sky Survey 2. Acknowledgment: Davide De Martin

Our most basic view of the sky comes via our visible-light-sensitive eyes. Yes, we can see gorgeous stars, particularly this time of year when Orion and Taurus and the other constellations are riding high in the sky. But, we see only the wavelengths of light from stars and planets and nebulae and galaxies that our eyes can detect. 

All things radiate in more than one set of wavelengths of light. The Sun, for example, is visible in optical (visible) light, but also in radio frequencies, ultraviolet, infrared, and so on. To see the “other” light that things emit or reflect, we need other detectors to enhance our own senses.

The European Southern Observatory has a telescope called APEX outfitted with an instrument called the LABOCA camera. It is sensitive to submillimeter wavelengths of light. In the electromagnetic spectrum, these are wavelengths that lie between infrared and radio waves. They emanate from slightly warm objects, such as clouds of gas and dust in star-forming regions. “Warm” is a relative term. The clouds are heated by nearby stars and are hotter than surrounding space, but they’re actually cold enough that only infrared and submillimeter detectors can “see” them.  These wavelengths are what allows us to “peek inside” starbirth créches because those wavelengths of light can pass through the gas and dust clouds.

In this image, we see a sinuous filament of gas and dust in the constellation Taurus. It’s part of a larger nebula called the Taurus Molecular Cloud. This segment you see here is about 10 light-years long. It contains dense clouds of gas that are going to collapse in on themselves to make new stars. There are also newborn stars in the cloud, visible as a faint glow in LABOCA’s view.

Our skies are filled with places like this, where the constant cycle of star birth takes place, using hydrogen gas and clouds of material formed in previous stellar explosions to create newborn stars. Fortunately, we have incredibly great detectors to show us what’s really happening among the stars!