SPIDER (balloon-borne instrument)
Generated by GPT-5-miniExpansion Funnel Raw 72 → Dedup 0 → NER 0 → Enqueued 0
| SPIDER (balloon-borne instrument) | |
|---|---|
| Name | SPIDER |
| Caption | SPIDER instrument during integration |
| Mission type | Balloon-borne polarimeter |
| Operator | Columbia University / Princeton University / California Institute of Technology |
| Manufacturer | Multiple institutions |
| Launch site | McMurdo Station / Long Duration Balloon operations |
| Launch date | 2015, 2018 |
| Mission duration | Weeks (stratospheric) |
| Instruments | Six (or more) cryogenic telescopes, transition-edge sensors |
| Wavelength | Microwave / submillimeter |
| Objectives | Measure cosmic microwave background polarization |
SPIDER (balloon-borne instrument) is a stratospheric polarimeter designed to measure the polarization of the cosmic microwave background (CMB) at degree angular scales. Developed by a collaboration including Columbia University, Princeton University, and the California Institute of Technology, SPIDER flew on long-duration balloon campaigns from Antarctica to probe signatures of primordial inflation and galactic foregrounds. The project bridges efforts by collaborations such as BICEP2, Planck (spacecraft), and WMAP and has informed studies by teams at Harvard University, MIT, and University of Chicago.
Overview
SPIDER was conceived within the context of experimental CMB programs led by institutions like University of California, Berkeley, Stanford University, Yale University, University of Minnesota, and University of British Columbia. The instrument arrays detectors similar to those used in projects at Jet Propulsion Laboratory, NASA centers, and laboratories affiliated with Brookhaven National Laboratory and Argonne National Laboratory. SPIDER's Antarctic campaigns leveraged logistics from United States Antarctic Program operations at McMurdo Station and long-duration balloon technology developed by Columbia Scientific Balloon Facility and NASA Goddard Space Flight Center. The collaboration includes scientists who have participated in experiments such as POLARBEAR, ACT (Atacama Cosmology Telescope), SPT (South Pole Telescope), and EBEX.
Instrument Design
SPIDER employs multiple cryogenic refracting telescopes fitted with polarization-sensitive bolometers based on transition-edge sensor (TES) technology developed in laboratories like NIST, KEK, and university cleanrooms. The focal planes are read out using time-domain multiplexing electronics similar to systems used by BICEP and Keck Array. The payload integrates pointing systems derived from designs used by BOOMERanG and Archeops, with star cameras, gyroscopes, and sun sensors calibrated against catalogs such as Hipparcos and Gaia (spacecraft). Cryogenics are maintained by liquid helium systems analogous to those at Northrop Grumman cryogenic facilities and informed by heritage from Planck (spacecraft) instrument teams. Optical elements include refracting lenses and half-wave plates similar to devices used on MAXIMA and OLIMPO telescopes.
Scientific Objectives
Primary objectives target B-mode polarization from primordial gravitational waves predicted by models of cosmic inflation proposed by theorists associated with institutions like Princeton University and Harvard University. SPIDER aims to measure the tensor-to-scalar ratio r at degree angular scales, complementing constraints from Planck (spacecraft) temperature maps and polarization analyses by WMAP. Secondary goals include characterizing polarized emission from galactic dust and synchrotron traced by surveys from IRAS, WISE, and radio arrays such as Very Large Array and Australian Square Kilometre Array Pathfinder. The experiment contributes to foreground separation techniques developed in conjunction with teams from University of Oxford, University of Cambridge, and Max Planck Institute for Astrophysics.
Flight Operations and Missions
SPIDER completed long-duration Antarctic flights launched from facilities supported by Raytheon Technologies logistics and coordinated with United States Antarctic Program and National Science Foundation oversight. Flights were planned using trajectory models from NOAA and balloon operations coordinated with Columbia Scientific Balloon Facility. Campaign timelines mirror those of historic Antarctic balloon missions including BOOMERanG and BLASTPol, with recovery operations involving New Zealand logistics and aircrews. Flight hardware integration and preflight tests occurred at laboratories affiliated with Caltech, Princeton University, and Columbia University before deployment to McMurdo Station.
Data Processing and Analysis
Data reduction pipelines adapt algorithms used by collaborations such as BICEP2, Keck Array, SPTpol, and POLARBEAR, employing map-making codes that trace lineage to software developed at NASA Goddard Space Flight Center and Lawrence Berkeley National Laboratory. Time-ordered data are filtered, calibrated against celestial sources like Jupiter (planet) and the Crab Nebula, and passed to component-separation frameworks used by Planck (spacecraft), WMAP, and ground-based experiments at Atacama Cosmology Telescope. Statistical inference employs likelihood analysis and Monte Carlo techniques inspired by pipelines from CMB-S4 planning groups and theoretical inputs from researchers at Institute for Advanced Study and Perimeter Institute. Cross-correlation studies compare SPIDER maps with surveys by Herschel Space Observatory, Planck (spacecraft), and radio observatories including Effelsberg 100-m Radio Telescope.
Results and Discoveries
SPIDER has delivered measurements that constrain polarized foregrounds and provide upper limits on the tensor-to-scalar ratio r, informing interpretations alongside results from Planck (spacecraft), BICEP2, and Keck Array. Analyses have refined models of galactic dust polarization that relate to work by researchers at Max Planck Institute for Radio Astronomy and Institute of Astrophysics of Andalucía. SPIDER data have been used in joint studies with teams from Harvard-Smithsonian Center for Astrophysics, Princeton University, and Columbia University to improve constraints on inflationary scenarios advanced by theorists associated with Princeton Institute for Advanced Study and Perimeter Institute. The instrument's methodologies influenced design choices for future missions including LiteBIRD and ground arrays planned by the Simons Observatory and CMB-S4 collaborations.