SearcharxivSearch

arXiv · 2511.02985

The SPHEREx Satellite Mission

James J. Bock·Asad M. Aboobaker·Joseph Adamo·Rachel Akeson·John M. Alred·Farah Alibay·Matthew L. N. Ashby·Yoonsoo P. Bach·Lindsey E. Bleem·Douglas Bolton·David F. Braun·Sean Bruton·Sean A. Bryan·Tzu-Ching Chang·Shuang-Shuang Chen·Yun-Ting Cheng·James R. Cheshire IV·Yi-Kuan Chiang·Jean Choppin de Janvry·Samuel Condon·Walter R. Cook·Asantha Cooray·Brendan P. Crill·Ari J. Cukierman·Olivier Dore·C. Darren Dowell·Gregory P. Dubois-Felsmann·Tim Eifler·Spencer Everett·Beth E. Fabinsky·Andreas L. Faisst·James L. Fanson·Allen H. Farrington·Tamim Fatahi·Candice M. Fazar·Richard M. Feder·Eric H. Frater·Henry S. Grasshorn Gebhardt·Utkarsh Giri·Tatiana Goldina·Varoujan Gorjian·Salman Habib·William G. Hart·Chen Heinrich·Joseph L. Hora·Zhaoyu Huai·Howard Hui·Young-Soo Jo·Woong-Seob Jeong·Jae Hwan Kang·Miju Kang·Branislav Kecman·Chul-Hwan Kim·Jaeyeong Kim·Minjin Kim·Young-Jun Kim·Yongjung Kim·J. Davy Kirkpatrick·Yosuke Kobayashi·Phil M. Korngut·Elisabeth Krause·Bomee Lee·Ho-Gyu Lee·Jae-Joon Lee·Jeong-Eun Lee·Carey M. Lisse·Giacomo Mariani·Daniel C. Masters·Philip D. Mauskopf·Gary J. Melnick·Mary H. Minasyan·Jordan Mirocha·Hiromasa Miyasaka·Anne Moore·Bradley D. Moore·Giulia Murgia·Bret J. Naylor·Christina Nelson·Chi H. Nguyen·Hien T. Nguyen·Jinyoung K. Noh·Stephen Padin·Roberta Paladini·Sung-Joon Park·Konstantin I. Penanen·Dustin S. Putnam·Jeonghyun Pyo·Nesar Ramachandra·Keshav Ramanathan·Zafar Rustamkulov·Daniel J. Reiley·Eric B. Rice·Jennifer M. Rocca·Ji Yeon Seok·Roger Smith·Jeremy Stober·Sara Susca·Harry I. Teplitz·Michael P. Thelen·Volker Tolls

Abstract

SPHEREx, a NASA explorer satellite launched on 11 March 2025, is carrying out the first all-sky near-infrared spectral survey. The satellite observes in 102 spectral bands from 0.75 to 5.0 um with a resolving power ranging from 35 to 130 in 6.2 arcsecond pixels. The observatory obtains a 5-sigma depth of 19.5 - 19.9 AB mag for 0.75 to 3.8 um and 17.8 - 18.8 AB mag for 3.8 to 5.0 um after mapping the full sky four times over two years. Scientifically, SPHEREx will produce a large galaxy redshift survey over the full sky, intended to constrain the amplitude of inflationary non-Gaussianity. The observations will produce two deep spectral maps near the ecliptic poles that will use intensity mapping to probe the evolution of galaxies over cosmic history. By mapping the depth of infrared absorption features over the Galactic plane, SPHEREx will comprehensively survey the abundance and composition of water and other biogenic ice species in the interstellar medium. The initial data are rapidly released in the form of spectral images to the public. The project will release specialized data products over the life of the mission as the surveys proceed. The science team will also produce specialized spectral catalogs on planet-bearing and low-mass stars, solar system objects, and galaxy clusters 3 years after launch. We describe the design of the instrument and spacecraft, which flow from the core science requirements. Finally, we present an initial evaluation of the in-flight performance and key characteristics.

Explore related subjects

Keep this discovery

BibTeXRIS

James J. Bock, Asad M. Aboobaker, Joseph Adamo, Rachel Akeson, John M. Alred, Farah Alibay, Matthew L. N. Ashby, Yoonsoo P. Bach, Lindsey E. Bleem, Douglas Bolton, David F. Braun, Sean Bruton, Sean A. Bryan, Tzu-Ching Chang, Shuang-Shuang Chen, Yun-Ting Cheng, James R. Cheshire IV, Yi-Kuan Chiang, Jean Choppin de Janvry, Samuel Condon, Walter R. Cook, Asantha Cooray, Brendan P. Crill, Ari J. Cukierman, Olivier Dore, C. Darren Dowell, Gregory P. Dubois-Felsmann, Tim Eifler, Spencer Everett, Beth E. Fabinsky, Andreas L. Faisst, James L. Fanson, Allen H. Farrington, Tamim Fatahi, Candice M. Fazar, Richard M. Feder, Eric H. Frater, Henry S. Grasshorn Gebhardt, Utkarsh Giri, Tatiana Goldina, Varoujan Gorjian, Salman Habib, William G. Hart, Chen Heinrich, Joseph L. Hora, Zhaoyu Huai, Howard Hui, Young-Soo Jo, Woong-Seob Jeong, Jae Hwan Kang, Miju Kang, Branislav Kecman, Chul-Hwan Kim, Jaeyeong Kim, Minjin Kim, Young-Jun Kim, Yongjung Kim, J. Davy Kirkpatrick, Yosuke Kobayashi, Phil M. Korngut, Elisabeth Krause, Bomee Lee, Ho-Gyu Lee, Jae-Joon Lee, Jeong-Eun Lee, Carey M. Lisse, Giacomo Mariani, Daniel C. Masters, Philip D. Mauskopf, Gary J. Melnick, Mary H. Minasyan, Jordan Mirocha, Hiromasa Miyasaka, Anne Moore, Bradley D. Moore, Giulia Murgia, Bret J. Naylor, Christina Nelson, Chi H. Nguyen, Hien T. Nguyen, Jinyoung K. Noh, Stephen Padin, Roberta Paladini, Sung-Joon Park, Konstantin I. Penanen, Dustin S. Putnam, Jeonghyun Pyo, Nesar Ramachandra, Keshav Ramanathan, Zafar Rustamkulov, Daniel J. Reiley, Eric B. Rice, Jennifer M. Rocca, Ji Yeon Seok, Roger Smith, Jeremy Stober, Sara Susca, Harry I. Teplitz, Michael P. Thelen, Volker Tolls. 2025-11-04. The SPHEREx Satellite Mission. https://doi.org/10.3847/1538-4357%2Fae2be2

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

The EDD Radio Astronomy Backend Framework

Modern digital radio astronomy receivers produce increasingly wide-bandwidth, high bit-rate data streams that necessitate the development of flexible, scalable, and maintainable backend processing and recording systems. Historically, such backend instrumentation has been tightly coupled to telescope observing modes, limiting reuse between observatories and science cases. We present the Effelsberg Direct Digitisation (EDD) backend framework, a software-defined architecture for constructing real-time radio astronomy backends on commodity off-the-shelf computing infrastructure. We describe its design, implementation, supported observing modes, and operational deployments. EDD separates a common core framework from plugin-provided observing capabilities. The core provides orchestration, telescope interfaces, pipeline lifecycle management, monitoring, and deployment tooling, while plugins implement processing pipelines for specific observing modes. The framework is designed to support both single-dish and interferometric instruments through site-specific configuration and plugin selection. EDD currently supports spectroscopy and spectropolarimetry, pulsar timing and searching, baseband recording, very long baseline interferometry, correlation, and beamforming. Operational deployments include the Effelsberg 100-m telescope, the SKA-MPI prototype dish, the Thai National Radio Telescope, and the ARGOS interferometric prototype array. By separating common services, observing-mode plugins, and site-specific configuration, it allows backend capabilities to be deployed across heterogeneous telescope environments and provides a community resource for broadband radio astronomy instrumentation.

astro-ph.IM

Bayesian Superiority in On/Off analysis

We present a detailed comparison of Bayesian criteria with three non-informative priors - flat, Jeffreys, and scale-invariant - for testing a signal against an unknown background and compare them with the classical frequentist Li-Ma approach in the On/Off problem. We perform Monte Carlo simulations for various background levels and evaluate the Li-Ma and Bayesian criteria by their Type I error rates. We then simulate a nonzero signal and compare the criteria in terms of Type II error rates. We find that the Bayesian criterion with the Jeffreys prior yields lower Type I and Type II error rates than the Li-Ma criterion. In addition, we show that the Bayesian criteria are more robust than the Li-Ma criterion when the background distribution is overdispersed relative to the Poisson distribution.

astro-ph.IM

An RFSoC-based Backend and Timing System for the Balloon-borne Very Long Baseline Interferometry Experiment

We present the design and performance characterization of the digital backend and precision-timing system for the Balloon-borne Very Long Baseline Interferometry Experiment (BVEX), a pathfinder for high-frequency stratospheric VLBI at 22 GHz. The backend uses one of the four 14-bit analog-to-digital converter inputs on an AMD-Xilinx RFSoC 4x2. Although the converters support sampling rates up to 5 GSPS, the flight configuration digitizes the 2-4 GHz intermediate frequency at 4.096 GSPS. CASPER firmware provides both a high-resolution spectrometer for pointing and receiver verification, and a VLBI acquisition chain with two-bit requantization that records at a rate of about 8.2 Gbps. The timestamped data packets are sent over 100 Gigabit Ethernet (GbE) to a 16 TB NVMe array in a storage computer that draws approximately 70-80 W. The timing chain uses a Rakon oven-controlled crystal oscillator as a timing reference while a time-interval counter measures its drift relative to a GPS reference with approximately 60 ps resolution. This is the first deployment of an RFSoC-based VLBI backend and precision-timing system on a stratospheric balloon. Ground tests validated the backend, spectrometer, and timing chain. The August 2025 CSA STRATOS flight ended before reaching the target float altitude because of a balloon failure, and as a result no science observations were obtained. For the planned 2027 reflight, we are developing a conduction-cooled data storage computer with 24 TB of NVMe capacity and a direct data path from the 100 GbE interface to the NVMe array.

astro-ph.IM