Discovering the Sky at the Longest Wavelengths with Small Satellite Constellations

Abstract

Due to ionosphere absorption and the interference by natural and artificial radio emissions, ground observation of the sky at the decameter or longer is very difficult. This unexplored part of electromagnetic spectrum has the potential of great discoveries, notably in the study of cosmic dark ages and dawn, but also in heliophysics and space weather, planets, cosmic ray and neutrinos, pulsar and interstellar medium, extragalactic radio sources, and even SETI. At a forum organized by the International Space Science Institute-Beijing (ISSI-BJ), we discussed the prospect of opening up this window for astronomical observations by using a constellation of small or micro-satellites. We discussed the past experiments and the current ones such as the low frequency payload on Chang'e-4 mission lander, relay satellite and the Longjiang satellite, and also the future DSL mission, which is a linear array on lunar orbit which can make synthesized map of the whole sky as well as measure the global spectrum. We also discuss the synergy with other experiments, including ground global experiments such as EDGES, SARAS, SCI-HI and High-z, PRIZM/Albatros, ground imaging facillities such as LOFAR and MWA, and space experiments such as SUNRISE, DARE/DAPPER and PRATUSH. We also discussed some technical aspects of the DSL concept.

arXiv commentThe report of the ISSI-BJ forum on "Discovering the Sky at the Longest Wavelengths with Small Satellite Constellations" held on January 23-25, 2019. 62 pages

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Cited by in corpus (9)

• Transformative Science from the Lunar Farside: Observations of the Dark Ages and Exoplanetary Systems at Low Radio Frequencies
• Imaging sensitivity of a linear interferometer array on lunar orbit
• Large-scale Array for Radio Astronomy on the Farside
• The Electrical Design of a Membrane Antenna for Lunar-based Low-frequency Radio Telescope
• Confronting global 21-cm signal with ${\mathbb{Z}}_3$ symmetric dark matter models
• The Array of Long Baseline Antennas for Taking Radio Observations from the Sub-Antarctic
• On the accuracy of posterior recovery with neural network emulators
• Recovering 21cm Monopole Signals Without Smoothness
• An SBC-based controller and processor for the laboratory model of PRATUSH Digital Receiver