Abstract

Our dynamic infrared sky is hitherto largely unexplored. The infrared is key to understanding elusive stellar fates that are opaque, cold or dusty. When we saw the first electromagnetic counterpart to gravitational waves, it was the infrared that unveiled the otherwise opaque heavy element nucleosynthesis. The infrared data from neutron star mergers is the only method to probe the sites of the heaviest of the heavy elements in the periodic table. Exemplars of other infrared transients include (i) deeply enshrouded supernovae, (ii) stellar mergers with dusty winds, (iii) 8--10 solar mass stars experiencing e-capture induced collapse in their cores, (iv) formation of stellar mass black holes. I will describe multiple projects to chart the time-domain in the infrared. I will begin with the SPitzer InfraRed Intensive Transients Survey (SPIRITS) - a systematic search of ~200 nearby galaxies over the last six years. I will present the first science results from the Palomar Gattini IR surveyor - a new 25 sq deg J-band camera that robotically charts the dynamic infrared sky. We are now building the next generation WINTER and DREAMS cameras leveraging alternative InGaAs detector technology. En route to our dream machine in the Antarctic, we have started building cryoscope - a fully cryogenic telescope prototype.