For just a moment, think back to when the first computers containing Intel's 80486 processor were being released. Things were quite different back then.
On April 24, 1990, shuttle mission STS-31 saw Discovery launch the Hubble Space Telescope successfully into its planned orbit.
From Celebrating 25 years of the NASA/ESA Hubble Space Telescope:
On the 24 April 2015 the NASA/ESA Hubble Space Telescope will celebrate 25 years since its launch.
During the 1970s, NASA and ESA began planning for a space telescope that could transcend the blurring effects of the atmosphere and take clearer images of the Universe than ever before. In 1990 the idea finally became a reality and, despite a flaw in the main mirror which was quite swiftly corrected, Hubble has since far exceeded expectations.
It has delved deeper into the early years of the Universe than was ever thought possible, played a critical part in the discovery that the expansion of the Universe is accelerating and probed the atmospheres of planets around distant stars.
Hubble had 5 servicing missions. The main mirror was ground incorrectly, and a significant part of that first servicing mission was to install corrective optics. The effect was dramatic. Who can forget those amazing photos like The Pillars of Creation and Hubble Deep Field? Just think of all the fantastic pictures from Hubble that graced the Astronomy Picture of the Day!
What are your most memorable recollections of the Hubble Space Telescope's accomplishments? Did you see the launch of the telescope or one of the servicing missions? Did you play a role in any of its projects?
(Score: 4, Interesting) by kaszz on Friday April 24 2015, @07:49PM
So was the Intel 80486 the first one to be backdoored in hardware by that pesky organization that is so eager to listen in?
As for the first really memorable image by Hubble. It must be the one of a supposedly pitch dark patch where light over 11 days were collected in 2003/2004. And it was shown to full of galaxies and other stuff [wikipedia.org].
(Score: 3, Insightful) by Techwolf on Friday April 24 2015, @10:54PM
That image was just amazing and humbling when taken into context of just how small a spot in the sky was used to create it.
(Score: 5, Insightful) by bob_super on Friday April 24 2015, @08:40PM
Thanks.
(Score: 2, Funny) by Anonymous Coward on Friday April 24 2015, @10:19PM
> What are your most memorable recollections of the Hubble Space Telescope's accomplishments?
> Did you see the launch of the telescope or one of the servicing missions?
> Did you play a role in any of its projects?
I particularly remember on the day of the 25th anniversary reading some cheesy questions on some website trying to elicit posts. Heh, still makes me queasy even now. What would YOU do?
(Score: 4, Informative) by takyon on Friday April 24 2015, @11:24PM
It's easy to play a "role" in its "projects":
http://www.galaxyzoo.org/ [galaxyzoo.org]
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 4, Interesting) by MichaelDavidCrawford on Saturday April 25 2015, @12:17AM
The most common way to test a telescope mirror is the Foucault Test, in which a pinhole or slit with a lamp behind it illuminates the mirror. The refocused beam is a little bit to one side as the pinhole is moved a little bit to the other side. At the focus the image of the pinhole is partially interrupted with a knife edge. This has the effect of greatly magnifying any deviation of the mirror from a sphere. You can even see the thermal expansion of the glass if you put your thumb on it for a moment.
But the space telescope's mirror was not a sphere, I think it was a hyperbola, with the whole system to form a Ritchey-Chretien. A variation of the Foucault Test uses a "Null Adaptor" consisting of a short metal tube of a precise length as well as a plano-convex lens. It was that metal tube that was the wrong length.
I often wondered about this as I could have gotten that tube right in the garage of the house where I lived while in high school. using a piece of copper drainpipe, a hacksaw and a cheap plastic vernier caliper.
The ultimate cause?
Whoever calculated the length of that tube dropped a sign.
Yes I Have No Bananas. [gofundme.com]
(Score: 4, Interesting) by Yog-Yogguth on Saturday April 25 2015, @01:32PM
There's the official version of events [wikipedia.org] as described on Wikipedia. That version reeks of bullshit and you've already pointed out why as you (and lots of other people making their own optics and telescopes) would have done a better job.
Optics are like Mars rovers or any other piece of highly specialized equipment: the additional cost of making “one more” is only a small fraction of the cost of making “only one” (or only two, or three, four…) because so much of the initial cost is connected to doing something new (not necessarily a new concept but to new limits and/or different design restraints, and perhaps with new technologies and/or new methods and new materials or coatings) for the first time. It's the price of initial setbacks, failures, and acquiring practical knowledge.
More likely what happened is that the optics of the Hubble Space Telescope (HST) weren't designed to look at stars but instead had other design constraints. The optics would have been designed for the Hubble's sibling(s) which paid for most or all of the initial cost of the optics. That would be the KH-11 Kennan [wikipedia.org] which was made to look at Earth and which had adjustable secondary mirrors (and the HST doesn't have that). Here's a photo [wikipedia.org] believed to be from one of those, a photo released in 1997 or so and thought to be taken in 1984, it has been modified to be fit for public release thus most likely been given an artificial lower resolution so as to not betray the true capabilities. The bomber in the picture is nearly 35 meters wide and long.
One can compare it to the recent situation with the more modern surplus optics donated to the NASA from the NRO. It's basically the same situation only more public and those new mirrors are from the NRO programs that upgraded or expanded upon KH-11 (at the point in time where they had stopped with the KH naming). Great optics but unlikely to ever be put to use as space telescopes because it will be so expensive to use them.
Remember that KH-11 was launched into space in 1976 and the HST was launched into space in 1990 fourteen years later. Considering all available information the HST is practically guaranteed to have been using spare outdated NRO optics.
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