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Science Goals

Science Objectives

Physical Parameters

Observables

Instrument Requirements

Projected Performance

Mission-Level Requirements

Characterize radio foregrounds in the 1-100 MHz frequency range to determine feasibility of ground and space-based HI intensity mapping experiments probing the Dark Ages and Epoch of Reionization.

Related NASA Objectives from the Astrophysics Roadmap and Astro2020 Decadal Survey:

  • Probe structure of dark ages & epoch of reionization
  • Characterize 1st starlight in the universe
  • Test cosmological models & nature of dark matter

Determine whether HI absorption by spinning dust grains poses a significant foreground contaminant for both ground and space-based measurements of HI from Cosmic Dawn.

Total, all-sky averaged brightness temperature (i.e., intensity referenced to a blackbody spectrum) measured by the antenna as a function of frequency between 1-100 MHz. 

A ~50 mK absorption feature in the 20-80 MHz range produced by the absorption of Galactic synchrotron emission by interstellar dust.

Frequency resolution: ≤ 50 kHz��Min. Frequency: 1 MHz��Max. Frequency [Baseline]: 100 MHz

Max. Frequency [Threshold]: 90 MHz��System Temperature: <350 K��Sampling Time: <= 1 min.��Antenna Length: 3.3 meters��

Frequency resolution: 50 kHz��Min. Frequency: 1 MHz��Max. Frequency: 90 MHz��System Temperature: 250 to 330 K��Sampling Time: 1 min��Antenna Length: 3.3 meters

Total observation time ~560 hours when the spacecraft is on the far side of the Moon from waning through waxing gibbous lunar phases. 

Antenna boresight at declination of –70+/-10 deg and right ascension between |20+/-10| and |80+/-10| deg to avoid the Galactic plane 

Location: +/- 65 degrees from the anti-Earth point to overlap with projected location of FARSIDE.

Orbital altitude <100 km to optimize shielding from terrestrial RFI on the lunar far side.

RFI/EMI <-80 dB suppression to avoid self noise from the spacecraft. 

Measure the spectrum of Galactic synchrotron emission in the 1-100 MHz frequency range. 

All-sky averaged brightness temperature of Galactic synchrotron radiation as a function of frequency.

Distinguish terrestrial and solar-origin radio frequency interference (RFI) in terms of peak frequency and bandwidth, temporal duration, and intensity.

Total RFI intensity as a function of time or orbital phase. RFI sources include terrestrial-based radio sources (e.g., satellite telecommunications) and solar radio bursts.

Frequency-time dynamic spectra covering 1-100 MHz with a sampling time < 1 minute in order to resolve short time-scale RFI.