DEEP SPACE 1420 • 2026

1420 MHz Neutral-Hydrogen Spectral FFT Survey

Eleven 24-hour spectral observations across 69°–89° azimuth

Deep Space 1420 • 2026 • Mishawaka, Indiana • 4.5-meter radio telescope • 1420.4058 MHz

Observation Summary

Frequency	1420.4058 MHz neutral-hydrogen (H I) line
Observing location	Mishawaka, Indiana (approximately 41.66° N, 86.16° W)
Observing mode	24-hour spectral FFT observations
Elevation	58° for all observations
Azimuth coverage	69° through 89° in 2° increments
Observed azimuth positions	11
Azimuths	69°, 71°, 73°, 75°, 77°, 79°, 81°, 83°, 85°, 87°, 89°

The Deep Space 1420 radio telescope conducted a coordinated set of eleven 24-hour spectral FFT observations of Galactic neutral-hydrogen emission at 1420.4058 MHz. The telescope remained at 58° elevation while azimuth was stepped from 69° through 89° in 2° increments. These observations preserve spectral information across the hydrogen line and show relative H I intensity together with measured velocity structure.

Figure 1 — Polar Hydrogen Intensity Visualization

The polar plot presents relative measured H I intensity through a complete 24-hour observing cycle. Angular position represents progression through the observation rather than literal Galactic direction, and the circular display should not be interpreted as the physical shape or radial structure of the Milky Way.

Figure 1. Polar visualization of relative 1420 MHz H I intensity through the 24-hour observing cycle.

Figure 2 — 3D Hydrogen Intensity Map

The spectral data were rendered against radial velocity and right ascension to show how measured H I intensity varies through the observing cycle. The resulting surface emphasizes the velocity structure contained in the FFT measurements rather than only the total received signal.

Figure 2. Three-dimensional spectral intensity distribution plotted by radial velocity and right ascension.

Figure 3 — H I Velocity Ridge Map

The velocity-ridge rendering isolates the dominant spectral H I feature and follows its relative intensity with right ascension. This representation makes the persistence and variation of the principal hydrogen-line velocity component easier to compare across the 24-hour spectral record.

Figure 3. Three-dimensional H I velocity ridge showing the dominant spectral component through right ascension.

Figure 4 — 3D Hydrogen-Line Radio Terrain

The eleven 24-hour spectral observations were combined into a multi-azimuth H I terrain product. Right ascension and declination define the survey coordinates, relative H I signal forms the surface height, and color represents the peak measured velocity across the reconstructed field.

Figure 4. Baseline-matched 3D H I radio terrain from the 11-position spectral survey, with a top-down projection.

Survey Interpretation

Together, the polar intensity visualization, spectral intensity surface, velocity-ridge rendering, and final multi-azimuth terrain document complementary views of the same 1420 MHz FFT survey. The sequence progresses from the 24-hour intensity record to velocity-resolved spectral structure and concludes with the combined 11-azimuth survey product.

The repeated 24-hour measurements across eleven closely spaced azimuth positions provide a basis for comparing persistent H I spectral structure across neighboring telescope pointings. The visualizations are derived from the measured survey data and are intended to represent relative radio intensity and spectral velocity structure rather than literal three-dimensional Galactic geometry.