Up and Across the Ramps: Enabling Solar System Science from Roman Level One Data
PI: Golovich, Nathan, Lawrence Livermore National Security, LLC
Wide-Field Science – Large
The Nancy Grace Roman Space Telescope is widely anticipated to enrich the study of galactic astrophysics and cosmology. Much less appreciated by the community is Roman’s importance for solar system science. Roman’s Wide Field Instrument (WFI) will capture hundreds of minor planets in every exposure that intersects the ecliptic plane. Because solar system observations did not drive the development of the calibration software and survey strategy, significant challenges are present that will prevent Roman from delivering its full potential without modifications. Unlike all distant sources, solar system bodies move appreciably over a single exposure. This motion has problematic interactions with the WFI’s “up-the-ramp” measurement process. Moving object flux will be inadvertently erased from the Level 2 data products by the calibration pipeline’s ramp fitting and cosmic ray (CR) detection algorithms. The process will leave “ghost images” in Level 2 images that will propagate to difference images and thereby affect any further analysis including transient alerts. The way in which moving objects will affect the Level 1 and 2 data products (and beyond) has not been characterized to date and the impact they will have on downstream science is unknown.
We propose to develop algorithms and software to simulate, identify, characterize, and preserve moving objects in the Level 1 data. The detected moving object catalogs can then be used to support all further data analysis. These tools will enhance Roman science by enabling the detection and characterization of minor planets throughout the solar system. This will offer a unique window into fundamental scientific questions about the solar system, the answers to which have broad implications across science, including biology, geology, planetary defense, and the growing space economy.
In this proposal, we demonstrate the challenges of moving objects and describe a set of specific simulation and data analysis tasks that are tractable and capable of delivering on Roman’s full potential as a solar system science asset in the coming years. The goals of our proposal are:
Overarching Goal: Preserve moving object detections that are present in the Roman Level 1 Data
• Goal 1: Simulate the effect of ramp fitting, jump detection, and CR removal on moving objects in the Roman data reduction
• Goal 2: Build a pipeline that creates a new Level 4 moving object catalog and complementary Level 2 “intra-exposure difference images” from the Level 1 data cubes
• Goal 3: Create an alert and moving object linking pipeline"