A Search for Peculiar Objects with the NASA Orbital Debris Observatory 3-m Liquid Mirror Telescope

Abstract

The NASA Orbital Debris Observatory (NODO) astronomical survey uses a transit 3-m liquid mirror telescope to observe a strip of sky in 20 narrow-band filters. In this article, we analyze a subset of data from the 1996 observing season. The catalog consists of 18,000 objects with 10<V<19 observed in 10 narrow-band filters ranging from 500 nm to 950 nm. We first demonstrate the reliability of the data by fitting the Bahcall-Soneira model of the Galaxy to the NODO magnitude counts and color counts at various galactic latitudes. We then perform a hierarchical clustering analysis on the sample to extract 206 objects, out of a total of 18,000, showing peculiar spectral energy distributions. It is a measure of the reliability of the instrument that we extract so few peculiar objects. Although the data and results, per se, may not seem otherwise particularly remarkable, this work constitutes a milestone in optical astronomy since this is the first article that demonstrates astromomical research with a radically new type of mirror.