Press play above to view a zoom-out animation of the Lynx Legacy Field
the Shape of the Expanse
The Lynx Legacy Field, a 10 square degree map of the largest structures in the Universe, is a notional 10 megasecond program that would reign among the Observatory’s most revolutionary achievements. Focused on a previously identified low-redshift large scale structure, this survey will reveal a massive galaxy cluster anchored to the void by Cosmic Web filaments that have, thus far, never been truly observed.
The full image above shows a realistic mock of soft X-ray surface brightness from the Hydrangea simulation, with a true Lynx surface brightness sensitivity cutoff applied. A large mosaic of individual 100 ksec HDXI exposures, the Legacy Field will maintain sub-arcsecond imaging across the entire field, and every individual 100 ksec footprint in the mosaic will reach a greater depth than the deepest region of the 7 Msec Chandra Deep Field South. While the image of the filamentary web and its cluster-scale node will be a revolutionary achievement on its own, even individual “blank” regions of the image would contain an exquisite array of high- and low-redshift AGN, clusters, and groups. This is illustrated in the bottom two panels of the above figure, which show (at bottom left) a zoom-in on a simulated single 100 ksec HDXI footprint of a “blank” region of the Legacy Field. Nearly seven thousand discrete sources will be detected in a single 22′×22′ field of view. It is the ability to detect and mask these sources that gives Lynx access to the very low surface brightness levels needed to reveal the Cosmic Web. The lower right panel shows a further zoom-in on this “blank” field exposure, revealing a blindly detected 10¹³ solar mass galaxy group at redshift z = 3.27, the epoch of formation of the earliest galaxy groups and protoclusters. The Lynx Legacy Field will be among the richest X-ray datasets ever obtained, and reign as a lasting triumph of science.
