Astronomers create 'light-fingerprints' to reveal mysteries of cosmos

A new databased uses "light-fingerprints" to catalogue the geometric albedos and calibrated spectra of the Milky Way's celestial bodies.

Tyler MacDonald | Oct 11, 2019

Astronomers have created "light-fingerprints" to organize a reference catalogue of geometric albedos and calibrated spectra of 19 diverse bodies in the Milky Way, including all eight planets and two dwarf planets.

Through the comparison of observed spectra and exoplanet albedos, scientists can characterize our planetary system and compare outside exoplanets to the worlds that populate our own system.

"We use our own solar system and all we know about its incredible diversity of fascinating worlds as our Rosetta Stone," said Lisa Kaltenegger of the Carl Sagan Institute and co-author of the study. "With this catalog of light-fingerprints, we will be able to compare new observations of exoplanets to objects in our own solar systemincluding the gaseous worlds of Jupiter and Saturn, the icy worlds of Europa, the volcanic world of Io and our own life-filled planet."

The catalog can be accessed for free at the Carl Sagan Institute website and includes both low- and high-resolution forms of the data. Not only that, but the catalog also reveals examples of how the colors of each of the solar system models shift if they were in the orbit of stars other than our system's sun.

"Planetary science broke new ground in the '70s and '80s with spectral measurements for solar system bodies. Exoplanet science will see a similar renaissance in the near future," said Jack Madden, doctoral candidate at the Carl Sagan Institute and lead author of the study. "The technology to directly collect the light from Earth-sized planets around other stars is currently in a clean room waiting to be assembled and trained on the right target."

"With the upcoming launch of the James Webb Space Telescope and the current construction of large ground-based telescopes such as the Giant Magellan Telescope and the Extremely Large Telescope, we are entering a new age of observational ability, so we need a reference catalog of all the planets and moons we already know, to compare these new exoplanet spectra to."

The findings were published in Astrobiology.