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Hubble telescope discovers oldest galaxy
October 29, 2013 - Stephen Browne
z8_GND_5296 is not what you call a real exciting name, but the reality is exciting enough.
Observations by the Hubble Space Telescope and Keck Observatory in Hawaii have confirmed the galaxy with that unexciting moniker is the oldest and most distant in the universe found to date.
z8_GND_5296 formed within 700 million years after the Big Bang, making it about 95 percent of the age of the universe. It is about 13.1 billion light-years away, which means that we're seeing it as it was 13.1 billion years ago when it was young and generating new stars at a furious rate.
The Hubble Space Telescope was launched into low Earth orbit in 1990. The idea for space-based telescopes has been around since at least 1923. The advantage of a space telescope versus ground-based astronomy is on Earth the atmosphere creates optical distortions we see as the twinkle in little stars, and absorbs much of the infrared and ultraviolet light.
After the Hubble was launched it was discovered its mirror had been ground incorrectly and it wouldn't perform at the optimal level expected. It still preformed scientifically useful observations though, and in 1993 the first of four servicing missions conducted from the Space Shuttle repaired and upgraded the Hubble.
The things accomplished using the Hubble, though largely unheralded, are breathtaking. Because of the Hubble we now know the rate of expansion of the universe, a phenomenon first discovered by astronomer Edwin Hubble (1889-1953) for whom the telescope is named. And that's only one of many breakthroughs in astrophysics that have come from Hubble observations.
The Hubble is expected to keep operating through at least 2014, maybe until 2020. Considering that Mars Exploration Rover, which landed on Mars on January 25, 2004, is still functioning under much greater environmental stress than the Hubble that's probably not too much to hope for.
A successor the James Webb Space Telescope (JWST) is scheduled for launch in 2018. It will orbit far higher than the Hubble and benefit from all the advances in space hardware made since 1990. Given what the Hubble has accomplished, we can hardly imagine what will come from the JWST.
The Hubble's cumulative costs were estimated at about $10 billion as of 2010. For the JWST they're talking about $8 billion, but with the way the government works one might expect cost overruns.
Nevertheless I am reminded of something I once heard scientist and SciFi author Jerry Pournelle say at a presentation at Oklahoma University once.
Pournelle observed that when the government gives lots of money to social scientists and educators, very often the results are either nothing or downright counterproductive. You give money to scientists and engineers and though there may be massive waste - at least you get something for it.
I wonder if future generations will look back and think we lived in the most exciting time in history, and never noticed it.
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