telescope could not be lowered enough to be aimed at objects around the north celestial pole. This telescope would never see Polaris.
The auxiliary mirrors, eyepieces, spectroscopes, and other instruments that would record the light of faint objects were mounted at the opposite end of the tube from the mirror, all in precise alignment with the primary mirror. A deviation of a fraction of a millimeter in the alignment would degrade the image. The tiniest wobble in the mounting would make the image too unsteady for photography or spectroscopy. Astronomical telescopes are unforgiving instruments.
The twenty men on the mountaintop that night included astronomers, machinists, electricians, and carpenters. Hale had also invited the poet Alfred Noyes, in the hope that he might capture and record the majesty of the occasion of first light. Hale deliberately did not invite the press. Hale had a scientist’s skepticism of journalistic oversimplification and sensationalism. Noyes captured Hale’s fears of the press:
As for the stars, if seeing them were all,
Three thousand million new-found points of light
Is our rough guess. But never speak of this.
You know our press. They’d miss the one result
To flash “three thousand millions” round the world.
Once the sun dropped below the horizon, the only illumination inside the dome was dim red night-lights. They too would be turned off when the actual observations began. Through the open shutters of the huge dome, the visitors could see the sky, punctuated with uncounted pinpoints of light. Even for the experienced astronomers, who had spent hundreds of nights on mountaintops with the big telescopes, it was an inspiring sight. Mountaintop observatories create the feel of a cathedral, with the heavens as their ceiling.
If it worked, the new telescope would almost triple the light-gathering ability of the sixty-inch telescope Shapley had used for much of his work. But in 1917 no one could say for sure whether a telescope as large as the new one-hundred-inch reflector would ever achieve its theoretical resolution of faint and distant objects. The effective resolution of a large telescope is limited by the turbulence of the earth’s atmosphere. Mixed air of varying density, which produces the twinkling of stars, leads to irregular refraction under magnification: Stars appear as blurred images instead of pinpoints of light. The larger the lens or mirror of a telescope, the more light rays from widely separated paths are united in a single image, and the more sensitive the instrument becomes to the tremors of the atmosphere. Even at a site like Mount Wilson, with its superb seeing, there were many who thought that the sixty-inch telescope was already pressing against the limits.
Although the new telescope was intended for use almost exclusively for photographic and spectrographic work, an eyepiece was mounted that evening so they could visually test its resolution and light-gathering ability. When the sky was dark enough, Walter Adams pressed buttons on the control panel to swing the great telescope around toward Jupiter. The others gathered around the base of the telescope as Hale was given the privilege of the first look through the eyepiece. He climbed the ladder to the eyepiece, high above the concrete floor, stared for a moment, then came down the ladder without saying a word.
Adams, an astronomer and experienced optician, went next. He couldn’t believe what he saw through the eyepiece. Instead of a single image of Jupiter, there were six or seven overlapping images in the eyepiece. “It appeared,” Adams later wrote, “as if the surface of the mirror had been distorted into a number of facets, each of which was contributing its own image.” If that was the best the telescope could do, it was worthless for astronomical work.
Hale and Adams looked at each other, wondering if the predictions of doom for the big telescope had come true. Had telescope building reached its
The auxiliary mirrors, eyepieces, spectroscopes, and other instruments that would record the light of faint objects were mounted at the opposite end of the tube from the mirror, all in precise alignment with the primary mirror. A deviation of a fraction of a millimeter in the alignment would degrade the image. The tiniest wobble in the mounting would make the image too unsteady for photography or spectroscopy. Astronomical telescopes are unforgiving instruments.
The twenty men on the mountaintop that night included astronomers, machinists, electricians, and carpenters. Hale had also invited the poet Alfred Noyes, in the hope that he might capture and record the majesty of the occasion of first light. Hale deliberately did not invite the press. Hale had a scientist’s skepticism of journalistic oversimplification and sensationalism. Noyes captured Hale’s fears of the press:
As for the stars, if seeing them were all,
Three thousand million new-found points of light
Is our rough guess. But never speak of this.
You know our press. They’d miss the one result
To flash “three thousand millions” round the world.
Once the sun dropped below the horizon, the only illumination inside the dome was dim red night-lights. They too would be turned off when the actual observations began. Through the open shutters of the huge dome, the visitors could see the sky, punctuated with uncounted pinpoints of light. Even for the experienced astronomers, who had spent hundreds of nights on mountaintops with the big telescopes, it was an inspiring sight. Mountaintop observatories create the feel of a cathedral, with the heavens as their ceiling.
If it worked, the new telescope would almost triple the light-gathering ability of the sixty-inch telescope Shapley had used for much of his work. But in 1917 no one could say for sure whether a telescope as large as the new one-hundred-inch reflector would ever achieve its theoretical resolution of faint and distant objects. The effective resolution of a large telescope is limited by the turbulence of the earth’s atmosphere. Mixed air of varying density, which produces the twinkling of stars, leads to irregular refraction under magnification: Stars appear as blurred images instead of pinpoints of light. The larger the lens or mirror of a telescope, the more light rays from widely separated paths are united in a single image, and the more sensitive the instrument becomes to the tremors of the atmosphere. Even at a site like Mount Wilson, with its superb seeing, there were many who thought that the sixty-inch telescope was already pressing against the limits.
Although the new telescope was intended for use almost exclusively for photographic and spectrographic work, an eyepiece was mounted that evening so they could visually test its resolution and light-gathering ability. When the sky was dark enough, Walter Adams pressed buttons on the control panel to swing the great telescope around toward Jupiter. The others gathered around the base of the telescope as Hale was given the privilege of the first look through the eyepiece. He climbed the ladder to the eyepiece, high above the concrete floor, stared for a moment, then came down the ladder without saying a word.
Adams, an astronomer and experienced optician, went next. He couldn’t believe what he saw through the eyepiece. Instead of a single image of Jupiter, there were six or seven overlapping images in the eyepiece. “It appeared,” Adams later wrote, “as if the surface of the mirror had been distorted into a number of facets, each of which was contributing its own image.” If that was the best the telescope could do, it was worthless for astronomical work.
Hale and Adams looked at each other, wondering if the predictions of doom for the big telescope had come true. Had telescope building reached its
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