Happy 25th anniversary Hubble! As of April 24, it has been a whopping quarter of a century since the Hubble Space Telescope (HST) rocketed out of Earth's atmosphere to begin its mission of surveying the stars. Since then, it's had a hand in... well, just about any space research you can think of. Now, on the advent of this landmark anniversary, we take a look at what the Hubble has accomplished, and what the future has in store for it.

All Hail the Hubble

So what is it that makes Hubble so special? Built by NASA with contributions from the European Space Agency (ESA), the telescope was the first large-scale, multi-purpose optical observatory ever sent into space.

Since its mission began, it has completed more than 130,000 orbits around Earth and captured more than one million images of astronomical objects - anything ranging from jaw-dropping galaxy clusters to moats of drifting dust.

And the data that has come from these observations has proven invaluable. In a recent Nature commentary about the telescope, Mario Livio, an astrophysicist at the Telescope Science Institute (STScI) in Baltimore, Md. even deduced that "more than 12,800 scientific articles have used HST results, and have been cited more than 550,000 times, making the telescope one of the most productive scientific instruments ever built." (Scroll to read on...)

So what are the secrets to Hubble's incredible fame and success?

Astronomer Patrick McCarthy, a prestigious Hubble Fellow and someone who spent a decade working towards upgrading the space telescope, recently explained to Nature World News (NWN) that one of Hubble's most obvious advantages over even some younger ground-based telescopes is that it is in space.

"A major part of Hubble's impact has been its ability to produce images of unrivaled sharpness due to its being above the Earth's atmosphere and the distortions that this introduces into the images," he explained. "This has led to breakthroughs in our understanding of galaxies and many other celestial phenomena." (Scroll to read on...)

[Credit: NASA/ESA] A brilliant display of Hubble's capabilities, this "anniversary fireworks" video showcases a giant cluster of about 3,000 stars called Westerlund 2, located in the constellation Carina 20,000 light-years away.

For instance, Hubble is often used to observe parts of the electromagnetic spectrum, such as infrared and ultraviolet light, that most other telescopes cannot detect. Those capabilities allow it to see deep into the Universe, peering past the blinding light of galaxy clusters to see ancient worlds a stunning 15 billion light-years away. Similarly, it can look nearby, closely observing new star nurseries that are flooded in ultraviolet light - information that hints at how our own Sun formed.

And while that's a lot to digest at once, it certainly isn't hard to at least appreciate the beauty of the images that Hubble captures. Just last year, NASA and the ESA teamed up to have Hubble recapture an image of the iconic Eagle Nebula (M16) that first earned its fame in 1995 as the so-called "Pillars of Creation."

McCarthy called the original image something that "captures the beauty of science in a way that few things do," but the new high-definition image is arguably even more breathtaking. (Scroll to read on...)

Released the first week into the 2015 year, NASA announced the image was captured "in celebration of [Hubble's] 25th anniversary," and showed that while Hubble is an 'old dog,' she certainly isn't out of new tricks.

"Even though the HST is celebrating its 25th anniversary, because it has been serviced regularly... its technology is very modern and it is now more powerful than ever," McCarthy said.

She's Still Kicking, But At What Cost?

The occasional servicing, some of it very drastic, has kept Hubble both 'afloat' and relevant. However, a NASA independent review panel determined that as of 2010, the HST has cost a stunning $10 billion (USD) in cumulative expenses.

That's why, for many years now, various committees and groups have been calling for the retirement of Hubble, especially following the announcement that the soon-to-launch James Webb Space Telescope (JWST) would be taking over many of its functions. (Scroll to read on...)

As the newcomer has sharper instruments, an orbit that takes it deeper into space, and a committed NASA team, many feel that Hubble's days are numbered.

However, even as the Director of the Giant Magellan Telescope (GMT) project - an instrument that will likely be able to replace a great deal of Hubble's infrared observations with images 10 times sharper - McCarthy strongly believes that the HST was and will continue to be worth its costs.

"If one looks at HST from a financial perspective, its $10B life-cycle cost amounts to $1.30 per American per year. This is the equivalent of one iTunes download," he said in amusement. "I doubt that one would have any argument with the proposition that the annual images from Hubble are worth at least as much as one pop song."

Even Astronaut Mike Massimino, who recently spoke with our sister-site's Kimberly M. Aquilina about his last mission servicing the incredible telescope, said he thinks that Hubble still has some time.

"[The JWST] will have more discovery power than the Hubble, but even if that goes successfully, the Hubble will continue to work until it doesn't work anymore," Massimino said with confidence. "Until it dies or fails, it will keep providing great discoveries." (Scroll to read on...)

A Steamroller For Science

And what more could we ask of a telescope that has so easily paved the way for successors like the JWST and the GMT? A strong proponent for STEM fields, McCarthy says that he's most appreciative of Hubble not for its scientific value, but for its ability to inspire new generations of astronomers and explorers.

"Spectacular images have brought astronomy to the forefront of the public's imagination, and hopefully caused humanity to think a little more about its place in the Universe," he said.

McCarthy added that he and his colleagues working on the GMT now hope they can fill those very big shoes.

"We have a strong desire to share all our stories, our progress and our science with the world, and allow those who are interested to have access to what inspires them," he explained. "We look to the example that the HST has set, and hope to do at least as well."

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