Clyde Tombaugh's Las Cruces sighting
On 20 August 1949 Clyde Tombaugh, the discoverer of Pluto, his wife and his mother-in-law saw a geometric group of faint, window-like lights glide silently across the sky over their back yard in Las Cruces.
1949 CE · 32.30, -106.76 · status: disputed
The account
Tombaugh worked at White Sands on missile tracking and remained cautious, but he stood by the observation and later said he had seen other unexplained objects.
The sceptical view
Menzel proposed reflections of town lights on a thin haze layer; there were no other witnesses.
The researched reading
The discoverer of Pluto saw a geometric group of faint lights. Birds lit by town lights or reflections are plausible; his expertise gives the case some weight.
| Explanation | Weight | Why |
|---|---|---|
| Something known, misidentified | 40% | A flock of birds (ducks or plovers) lit by town lights from below can appear as a geometric pattern of faint, window-like lights gliding silently, as in the Lubbock Lights of 1951. |
| Genuinely anomalous | 25% | Tombaugh stood by the observation and said he had seen other unexplained objects; but there were no other witnesses or instruments. |
| A known natural phenomenon | 15% | Menzel suggested reflections of town lights on a haze layer. |
| Secret human technology | 8% | Secret aircraft from White Sands could explain a pattern of lights. |
| A poorly understood natural phenomenon | 5% | A rare optical effect in the desert night sky is possible. |
| Perception, memory or mind | 5% | Trained observers are less prone to perception errors. |
| A hoax or fabrication | 2% | Tombaugh was a careful astronomer with no motive. |
Official position: No official investigation; Menzel proposed reflections of town lights on haze.