Flying Interferometers to Study Cosmic Molecules

SOFIA is an extensively modified Boeing 747SP with a 2.5 m (8.2’) reflecting telescope, making it the world’s largest airborne observatory. (Image courtesy of NASA.)

It’s hard not to be inspired by the progress we’ve made in cosmology, as a team of researchers and engineering students at Cornell can attest to. That’s why the team is working hard to develop a next-generation instrument to be placed on NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA), an airplane-turned-observatory exploring a variety of cosmological mysteries.

Detecting Cosmic Molecules with HIRMES

SOFIA is a modified Boeing 747SP (Special Performance) aircraft equipped with, among other instruments, an 8.2’ reflecting telescope. Designed specifically for infrared observations, SOFIA flies above most of the water vapor in Earth’s atmosphere. This allows it to receive a clearer signal than even the highest ground-based telescopes.

The observatory has many objectives, such as studying the birth and death of stars, black holes and the formation of solar systems. Another of SOFIA’s goals is the identification of complex molecules in space, and the Cornell team is working to develop several key instruments required for this task, called Fabry-Pérot interferometers.

The interferometers will be one component of the High Resolution Mid-Infrared Spectrometer (HIRMES), the third-generation instrument set to go up on SOFIA in spring 2019. “These very high spectral-resolution Fabry-Pérot interferometers are one of the two key technological challenges for the successful operation of HIRMES on SOFIA,” said team leader Gordon Stacey.

Comparing images of Jupiter taken with visible and infrared light. (Image courtesy of NASA.)

The team is set to deliver three high-resolution and mid-resolution interferometers, as well as two versions designed to image nearby galaxies. The interferometers are necessary to achieve the resolving power HIRMES needs in order to study the raw materials of life in the cosmos. A separate team from NASA is designing the second key component of HIRMES: sensitive bolometers to measure radiant energy.

HIRMES will augment SOFIA’s current array of instruments including cameras, spectrometers and photometers. It will be able to detect molecules of neutral atomic oxygen, water, hydrogen and deuterium (heavy hydrogen), using infrared wavelengths between 28 and 112 microns. NASA believes that detecting these wavelengths is key to learning how water vapor, ice, oxygen and cosmic dust combine to form planets.

You can learn more about SOFIA on NASA’s website. Or, for more space news, check out Spitzer Space Telescope is Repurposed 13 Years After Launch.