Speaker: Dr. Gary Melnick, Center for Astrophysics, Harvard & Smithsonian
Date/Time: November 15, 2024 / 12 noon central.
Location: NCSA, 1040.
Zoom: https://illinois.zoom.us/j/82318062756?pwd=M3g1MFF6cytsOWFEbmU0UW1XWVoxQT09
Title: SPHEREx: Extending Our Understanding of How New Worlds Obtain The Basic Ingredients for Life
Abstract:
When interstellar water was first detected in 1969 (through its 22 GHz maser transition), only five other molecules were known to exist in interstellar space, only eight planets beyond the Earth were known, the manner in which our solar system formed was unclear, and whether life might be possible beyond the Earth and our solar system was pure speculation. In the intervening 55 years, the advances have been nothing short of breathtaking. We now know of more than 330 interstellar and circumstellar molecules and molecular ions, some of which are complex organic building blocks of life. We also know of more than 5,700 confirmed extrasolar planets, including 963 multi-planet systems, and we routinely observe other solar systems in the making. All these discoveries encourage the belief that the chemistry in interstellar space is rich, and the products of this chemistry are likely inherited by a multitude of solar systems, some with Earth-like planets and moons in their habitable zones. As the ubiquity of this arc of evolution from molecular cloud to protoplanetary disk comes into increasing focus, the role of water and other key biological ingredients have assumed even greater interest, particularly the role of ices as the major conveyor of these key species to newly forming planets. I will review a few highlights of this journey to understand water’s indispensable role and the giant next steps we hope to take with SPHEREx, a NASA Medium-class Explorer Mission. Scheduled for launch in February 2025, SPHEREx is designed to conduct an all-sky spectroscopic survey between 0.75 µm and 5 µm. Among its goals, SPHEREx will carry out an unprecedented study of the abundance and distribution of biologically important ices throughout the Milky Way by means of absorption spectroscopy. This talk will discuss the impact of increasing the number of ice sightlines observed from a current value of several hundred to more than 9.9 million.