In the early 1960s, as NASA geared up towards space exploration, engineers and astronomers at the federal organization felt the need for a large telescope through which they could survey the planets before dispatching spacecraft to study them in detail. At the McDonald Observatory, in Texas, the new director Harlan J. Smith, saw an opportunity and convinced NASA to fund for a new one at the observatory.
McDonald Observatory was one of the premier destination for astronomy at that time because of the clear dry air of its location and moderately high elevation. It was also home to the 82-inch Otto Struve Telescope, using which German astronomer Gerard Kuiper discovered a new moon of the planet Neptune, named Nereid, in 1949. At the time of its construction in 1939, it was the world’s second largest telescope.
The dome of Harlan J. Smith Telescope. Photo: Fredlyfish4/Wikimedia
Director Smith felt the need for a new and larger telescope at McDonald Observatory. Thus, with the help of NASA’s generous contribution, a new telescope was built at the cost $5 million and completed in 1968. This new telescope was equipped with a 107-inch diameter fused silica mirror that gave it a light-gathering power one-quarter million times greater than the unaided eye.
Shortly after the telescope began regular observation, it became victim of an unfortunate incident involving a hand gun that left the telescope permanently scarred for life.
On February 5, 1970, shortly before midnight, a newly hired employee came in drunk with a 9mm gun to the observing floor of the telescope. First he fired a shot at his supervisor, and then taking aim at the telescope’s primary mirror emptied the rest of the clip at point blank range. The deranged employee, who was identified as Jack Hyde, a resident observer in charge of instrument maintenance, was quickly subdued and handed over to the police. The sheriff later told reporters that Hyde had drawn a pistol on two employees and had forced them to lower the mirror so he could fire at it.
Harlan J. Smith Telescope. Photo: Reddit
The mirror is the most important part of the telescope and is prepared with the utmost care. It took about a year for a team of experts to ground the 4.5 ton mirror, 24 hours a day, before it was installed. In the final stages, only one man at a time was permitted to execute the final touches where a wrong move would have damaged the instrument. And now, a mentally unstable employee had decided to take out his frustration on this delicate tool.
At first, the telescope’s mirror was described as a total loss and beyond repair. However, fused silica is more resilient than ordinary glass and the mirror did not shatter, but the bullets did leave small holes on the surface. Soon after the incident, Director Harlan J. Smith released a report describing the damage, or the surprising lack of it:
The harm suffered by the mirror from his bullets and his several preliminary blows with a hammer was extraordinarily small. The damage is limited to small craters about 3 to 5cm in radius, which reduce the light collecting efficiency by about 1 percent and introduce a very small amount of diffraction …… Astronomical observations of all types are essentially unimpaired by this tragic episode; the telescope resumed its observing program the following night, producing some of the best photographs (of quasar fields) so far obtained with this instrument in its first year of use.
The astronomers repaired the mirror by boring out the craters and painting them black to reduce any light-scattering effect, and the end result was simply a slight reduction in the efficiency of the telescope. It was now equivalent of a 106-inch telescope.
The bullet holes on the mirror clearly visible. Photo: McDonald Observatory
The telescope continues to provide service to astronomers. During the 1970s, the telescope was used to reflect a laser off mirrors left on the moon by Apollo astronauts, in a program called “lunar laser ranging.” These results have helped refine the distance to the Moon and enabled a better understanding of its interior, and provided a test of Albert Einstein's theory of General Relativity. The telescope has been extensively used to study the compositions of stars, the motions of galaxies, and to search for planets around other stars in our galaxy. In 2021, astronomers using this telescope discovered a massive black hole at the center of one of the Milky Way’s dwarf satellite galaxies, called Leo I. The black hole was as large as the one in our own galaxy. This unprecedented finding had the potential to shake up astronomers’ understanding of galaxy evolution.
In 1995, the 107-inch telescope was named Harlan J. Smith Telescope in honor of the man who served as director of McDonald Observatory from 1963 to 1989.
References:
# Harlan J. Smith Telescope, The University of Texas McDonald Observatory
# Texas Man Fires Into A Telescope, NY Times
# Texas Astronomers Discover Strangely Massive Black Hole in Milky Way Satellite Galaxy, UT News
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