2024-09-24T22:21:48.000Z http://sot.lmsal.com Mr. Sam Freeland Lockheed Martin Solar and Astrophysics Laboratory (LMSAL) http://www.lmsal.com Lockheed Martin Advanced Tech Center, 3251 Hanover Rd, O/ADBS, B/252, Palo Alto, CA 94304 null null HINODE SOTSP Arikawa Narukage Gopal V. (RCO) 410 HOP410 - North pole CH Coronal Hole, N Pole CH CH 11 20210113_060305 401 428 429 11 5 2000 2 1 1 2 0 81 1997 998 0.998 -700.143 489.232 316.366 162.304 2021-01-13T06:03:05.000Z 2021-01-13T07:06:18.000Z -700.143 489.232 Coordinated HSO Connect Observations of PSP Quiet-Sun Source Regions Fast map, full FOV, Q65, 1-side CCD Main Objective: To observe the full solar disk with XRT to identify energetic events that occur near the time of Parker Solar Probe (PSP) perihelion passage, where those energetic events might be the solar source for solar wind features detected in the heliosphere by PSP. IRIS will observe a location suspected to be a likely source location, based on magnetic-connectivity models. Scientific Justification: During earlier perihelion passages, PSP observed copious disturbances (called ?switchbacks?) in the solar wind. The solar source of those disturbances is plausibly in the chromosphere or corona, and various ideas have been proposed, including small-scale reconnection events. We seek to observe such possible events occurring at the footpoints of the magnetic field lines that extend out to PSP at any given time. As the solar source of the disturbances is unknown, we will observe the entire solar disk with XRT at moderate cadence to maximize the chance of pinpointing those source regions, under the assumption that they produce corresponding energetic XRT events. We will use a cool-temperature XRT filter, because the PSP disturbances are very common and therefore expected to originate from cooler-than-flare-temperature events. IRIS has a more limited FOV than XRT, and therefore its observations will focus on expected likely source locations. The proposers will search for candidate source regions using PFSS or MHD models of the heliospheric magnetic field connectivity. Final targeting information will be supplied to the operations teams beforehand, in accordance with the IRIS and Hinode operational requirements. This IHOP is a coordinated request from the three groups selected through NASA?s Heliophysics System Observatory Connect (HSOC) program and who plan to coordinate and make use of a wide range of remote-sensing observations. The requested observations will be shared among the HSOC groups to address multiple scientific questions. This IHOP should be run when activity level is low and the source region is predicted to be in quiet regions or coronal holes. A second IHOP by these same HSOC groups for observations during active periods is also available, and it should be run instead of this one when solar activity levels are high.;;Main Objective: To observe the full solar disk with XRT to identify energetic events that occur near the time of Parker Solar Probe (PSP) perihelion passage, where those energetic events might be the solar source for solar wind features detected in the heliosphere by PSP. IRIS will observe a location suspected to be a likely source location, based on magnetic-connectivity models. Scientific Justification: During earlier perihelion passages, PSP observed copious disturbances (called ?switchbacks?) in the solar wind. The solar source of those disturbances is plausibly in the chromosphere or corona, and various ideas have been proposed, including small-scale reconnection events. We seek to observe such possible events occurring at the footpoints of the magnetic field lines that extend out to PSP at any given time. As the solar source of the disturbances is unknown, we will observe the entire solar disk with XRT at moderate cadence to maximize the chance of pinpointing those source regions, under the assumption that they produce corresponding energetic XRT events. We will use a cool-temperature XRT filter, because the PSP disturbances are very common and therefore expected to originate from cooler-than-flare-temperature events. IRIS has a more limited FOV than XRT, and therefore its observations will focus on expected likely source locations. The proposers will search for candidate source regions using PFSS or MHD models of the heliospheric magnetic field connectivity. Final targeting information will be supplied to the operations teams beforehand, in accordance with the IRIS and Hinode operational requirements. This IHOP is a coordinated request from the three groups selected through NASA?s Heliophysics System Observatory Connect (HSOC) program and who plan to coordinate and make use of a wide range of remote-sensing observations. The requested observations will be shared among the HSOC groups to address multiple scientific questions. This IHOP should be run when activity level is low and the source region is predicted to be in quiet regions or coronal holes. A second IHOP by these same HSOC groups for observations during active periods is also available, and it should be run instead of this one when solar activity levels are high. ivo://sot.lmsal.com/VOEvent#2021-01-13T06:03:00Z