The launch of the Hubble Space Telescope marked a space-viewing milestone that many compare to when Galileo first pointed a telescope into space and discovered the rings of Saturn and the moons of Jupiter.
The idea was that while many advances in optics had been made since Galileo’s time, with huge arrays and telescopes built to take better and better pictures of the universe around us, there was still a severely limiting factor: Earth’s atmosphere.
Our atmosphere blocks a fair amount of light from the stars and can also create distortions that prevent clear images. Scientists tried to overcome these distortions by placing observatories up high in the mountains where the atmosphere is thinner, but that didn’t stop clouds or wet weather from blocking observations. In the 1900s, with rocket launches pushing boundaries closer and closer to space, it was agreed that an even better plan would be to gather images from a place where Earth’s atmosphere wouldn’t be a factor at all.
And so, the concept for the Large Space Telescope was born.
The optical telescope began as a joint operation between the European Space Agency and NASA in the 1970s, but it took until 1990 for it to launch. In that time, it was named for Edwin Hubble, a California astronomer who was known for having discovered some of the objects furthest from us in space — other galaxies. It was thought that the Hubble telescope would be able to capitalize on Hubble the astronomer’s discoveries and allow us to see those galaxies in much better clarity, paving the way for new revelations.
The creation of the telescope cost $1.5 billion in 1990 dollars, and carried sensitive photo equipment such as the Wide Field Planetary Camera, the Goddard High Resolution Spectrograph, the Faint Object Camera, the Faint Object Spectrograph and the High Speed Photometer. I do love how astronomers tend to name things exactly as they are.
Hubble’s launch from the space shuttle Discovery on April 24, 1990, was highly anticipated, and scientists waited eagerly to see the first beautiful images beam back to Earth from orbit.
Unfortunately, as the first few pictures revealed, there was a fatal flaw in the telescope’s primary mirror. The aberration was just 1/50 the thickness of a sheet of paper, but the results were blurry images that were essentially useless to astronomers.
It would take another three years and a space shuttle mission to get Hubble up and working as intended — but more on that next week.
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On a personal note, I want to thank everyone who has expressed concern for the fate of this column, in person and via email, upon hearing the news of our family’s move to Colorado. Luckily, the stars will look much the same in the sky from there (though I may be the tiniest bit closer, considering the elevation) and I look forward to continuing the joy of sharing stories of the stars with all of you.
LOOKING UP THIS WEEK: Mars will continue to brighten in the early morning sky along with the planet Saturn. Venus will stay a staple in the western evening sky with Jupiter rising in the early evening and making its way west as well. The moon is currently a waning crescent and will be new Wednesday.
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