First X-ray source in Volans

The first X-ray source in Volans is an extrasolar astronomical X-ray source that never received an X-1 (or "XR"-1, XR for X-Ray) designation.
Celestial sphere
The celestial sphere is divided into 89 areas. These are the IAU 88 official constellations of astronomy. Although there are only 88 IAU constellations, the sky is actually divided into 89 irregularly shaped boxes as the constellation Serpens is split into two separate sections, Serpens Caput (the snake's head) to the west and Serpens Cauda (the snake's tail) to the east. From each of these areas of the celestial sphere, incoming X-rays (X-radiation) have been detected above the Earth's atmosphere, as X-rays do not penetrate. Each area of the celestial sphere had at least one extrasolar astronomical X-ray source detected between June 12, 1962, Scorpius X-1, and April 6, 1980, Corona Australis X-1 (CrA X-1), though most never received the X-1 designation.
Volans as a constellation
Volans is a constellation in the southern sky. Of all the constellations it is 76th in celestial area at 141 sq. deg. A relatively uniform distribution of 1,000 astronomical X-ray sources would yield at least three in Volans. Or, by 1984 and the HEAO 1 A-1 catalog, (840 X-ray sources known), there might have been at least two X-ray sources in Volans.
Searching early catalogs
An early catalogue of discrete celestial X-ray sources, observed by sounding rockets and/or balloons, contains no source from the constellation Volans.
The UHURU catalog of X-ray sources (2U and before) contains no X-ray source in the constellation Volans.
The third Uhuru catalog of X-ray sources (3U and before) contains no X-ray source in Volans.
The fourth Uhuru catalog contains no X-ray source in the constellation Volans.
The HEAO 1 A-4 catalog of high-energy X-ray sources contains no sources detected in Volans.
The HEAO 1 A-1 catalog contains no X-ray source in Volans contemporary with the HEAO 1 A2 catalog sources.
The first two astronomical X-ray sources that the X-ray observatory satellite HEAO 1 detected in the constellation Volans are at H 0714-69
H 0714-69
H 0714-69 is in equatorial coordinates for the epoch 1950 B1950.0 at right ascension (RA) declination (Dec) shifted to J2000.0 RA Dec , where dates of observation are unknown but probably between August 12, 1977, and February 27, 1978.
According to SIMBAD, the X-ray astronomy satellite ROSAT detected ten visibly dark X-ray sources within 1° of H 0714-69.
H 0824-66
H 0824-66 is apparently detected first on January 5, 1978, at 19:41:07 UTC as a fast X-ray transient. The source location is at B1950.0 RA Dec shifts to J2000 RA Dec .
ROSAT detected ten visibly dark X-ray sources within 1° of H 0824-66. It also detected the star CPD-64 887 some 57' from H 0824-66 and 49' from 1H 0824-641.
Visibly dark X-ray source
Of the first X-ray sources discovered in each constellation (126 for 89 areas), some 63% are visibly dark. These visually dark X-ray sources can be radiative cosmic dust, hydrogen gas such as an H II region (e.g. the Orion Nebula), an H I region of hydrogen, a molecular cloud, or a coronal cloud.

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