LANDING SITE

The LuSEE-Night landing site is at 23°48'50"S 176°49'47"E, on a local topographical high point.  Close to anti-meridian, on the far side of the moon from the Earth, we are shielded from harmful terrestrial radio interference. The southern location gives us improved coverage by the relay communication satellite.

ANTENNAS

The antenna assembly consists of four 3-meter monopole antennas forming a cross-dipole configuration mounted on a motorized azimuth rotation platform referred to as a turntable.  This will allow us to reposition the antennas to measure different combinations of the sky signal in order to improve the component separation, as well as to control instrument systematics.

SPECTROMETER

The LuSEE-Night spectrometer will be an enhanced version of the Radio Frequency Spectrometer (RFS) flown as part of the FIELDS instrument suite on the Parker Solar Probe. It will use an updated architecture based on the Microsemi Polar Fire FPGA. It is designed to be a four-channel, full duty cycle spectrometer calculating all 4 posible auto- and 6 complex cross-correlations between 0.1-50MHz while conforming to stringent radio frequency interference (RFI) filtering and operational power requirements.

CALIBRATOR

A far-field orbiting calibrator is a crucial part of the LuSEE design and a major piece of  technology demonstration. A calibrator will send a single polarization coded digitally coded signal that will be detected in cross-correlation at high significance and in strong isolation, even in the presence of other strong signals from the sky. The calibration will allow us to measure the full spectral response of our instrument along many directions on the sky, and in combination with modeling will allow an unprecedented  control of systematics. Our antenna response will be, at the precision required for the Dark Ages experiment, sensitive to the electromagnetic properties of the lunar regolith, which are unknown in advance. The far field calibration will thus at the same time calibrate the response of our antennas, and give useful information about the lunar soil beneath the experiment. Bids will be solicited to produce a calibrator, to be delivered on the CLPS CS-4 mission.

COMMUNICATIONS

LuSEE-Night will land on the far side of the moon and thus be unable to communicate directly with Earth. We will rely on the European Space Agency's Lunar Path Finder satellite to send our data back to earth. A medium gain antenna, mounted on on the top of the instrument will enable our communication with the relay satellite.

POWER SUBSYSTEM

Approximately half of LuSEE-Night's weight will be in batteries (~50kg), which will be sufficient to deliver around 10W of power to the instrument during the lunar night. Batteries will ber recharged during the day using solar panels. All switched power supplies  will be heavily regulated using the so-called picket-fence-approach which stipulates that all clocks in the system, including those in the switching power-supplies, must be synchronized to the same master clock, thus isolating self-produced RFI to a narrow base frequency and its harmonics. This RFI will be digitally filtered out by the spectrometer with negligible signal loss. The delivery lander will become electrically passive after the first lunar sunset to further reduce locally generated RFI.