Bidiectional VNIR reflectance spectrum of the 25-125 micron size fraction OREX-800091-101 made by dry-sieving the hummocky rock OREX-800091-0 of asteroid Bennu was measured using RELAB Bidirectional Spectrometer at the standard viewing geometry of 30-degree incidence and 0-degree emergence angles.

20260623_VNMIR_BROWN_OREX-800091-101_1_VNMIRSpectralPoint_1.csv

20260623_VNMIR_BROWN_OREX-800091-101_1_VNMIRSpectralPoint_1.yaml

20260623_VNMIR_BROWN_OREX-800091-101_1_analysisLocation_1.jpg

20260623_VNMIR_BROWN_OREX-800091-101_1_analysisLocation_1.yaml

20260623_VNMIR_BROWN_OREX-800091-101_1_plot_1.png

20260623_VNMIR_BROWN_OREX-800091-101_1_plot_1.yaml

This material is supported by NASA PSEF grant.

Visible, near-, and mid-infrared spectroscopy

Custom bi-directional

Brown University

Standard deviation in reflectance over entire dwell time at that wavelength

Bidirectional visible and near-infrared reflectance spectrum of the 25-125 micron size fraction OREX-800091-101 of hummocky rock OREX-800091-0 of asteroid Bennu. The sample was loaded in a 9-mm black Teflon dish with a 7.2-mm field of view. RELAB sample ID is BN-REM-009-B, and spectral file name is C1BN09B. Wavelength range was 300-2600 nm, and the data were collected at every 5 nm. Reflectance is measured one wavelength channel at a time relative to Spectralon from Labsphere while both Spectralon and each sample were spun at a speed of 1.5 seconds per rotation during the measurements. Effects of Spectralon absorption features were corrected. Each measurement at each wavelength consists of a single scan with a dwell time that varies as a function of the albedo of the material at each wavelength. Minimum dwell time is 4.5 seconds, and the maximum dwell time is 34.5 seconds. Overlap region is averaged. A quartz depolarizer was used over 300-420 nm and 1780-2600 nm, and a calcite depolarizer was used over the wavelength range of 400-1800 nm. Albedo was adjusted to the visible range.

The analyzed spot is about 7.2 mm in diameter in the center of the sample mounted on a 9-mm diameter black Teflon dish.

A plot of bidirectional VNIR reflectance spectrum of the 25-125 micron size fraction OREX-800091-101 of hummocky rock OREX-800091-0 of asteroid Bennu.

Astromat

Bidirectional visible to near-infrared reflectance spectrum OREX-800091-101.

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