Slashdot Mirror
World's Largest Space Telescope Is Complete, Expected To Launch In 2018 (space.com)
An anonymous reader quotes a report from Space.com: After more than 20 years of construction, the James Webb Space Telescope (JWST) is complete and, following in-depth testing, the largest-ever space telescope is expected to launch within two years, NASA officials announced today (Nov. 2). NASA Administrator Charles Bolden hosted a news conference to announce the milestone this morning at the agency's Goddard Space Flight Center in Maryland, overlooking the 18 large mirrors that will collect infrared light, sheltered behind a tennis-court-size sun shield. JWST is considered the successor to NASA's iconic Hubble Space Telescope. The telescope will be much more powerful than even Hubble for two main reasons, Mather said at the conference. First, it will be the biggest telescope mirror to fly in space. "You can see this beautiful, gold telescope is seven times the collecting area of the Hubble telescope," Mather said. And second, it is designed to collect infrared light, which Hubble is not very sensitive to. Earth's atmosphere glows in the infrared, so such measurements can't be made from the ground. Hubble emits its own heat, which would obscure infrared readings. JWST will run close to absolute zero in temperature and rest at a point in space called the Lagrange Point 2, which is directly behind Earth from the sun's perspective. That way, Earth can shield the telescope from the sun's infrared emission, and the sun shield can protect the telescope from both bodies' heat. The telescope's infrared view will pierce through obscuring cosmic dust to reveal the universe's first galaxies and spy on newly forming planetary systems. It also will be sensitive enough to analyze the atmospheres of exoplanets that pass in front of their stars, perhaps to search for signs of life, Mather said. The telescope would be able to see a bumblebee a moon's distance away, he added -- both in reflected light and in the body heat the bee emitted. Its mirrors are so smooth that if you stretched the array to the size of the U.S., the hills and valleys of irregularity would be only a few inches high, Mather said.
20 years? That's a long time for something that has been done before. Maybe they were extra careful as the website suggests but 20 years is a bit excessive.
Don't be apathetic. Procrastinate!
Americans you are ridiculous. Ok I get it you have a two party system and therefore you are not accustomed to have different opinions in politics. It is always there team against ours. The truth is, it is you country. The country of all of you. Conservatives, liberals, socialists, Christians, Muslims, Buddhists, Jews, Atheists, Indians, etc. and you all life there. Unfortunately, for the next president you have two choices. They both have a big ego. And I am not sure if you could trust them, but you have to look at the potential outcome of each presidency. Clinton will not demolish your health care system, even if it sucks compared to European systems, Trump will. She will not start a war, but will continue with the drone program. With Trump, you do not know what he will do. Will he terminate NATO? Then many EU countries will try to build their own nuclear weapons. This is not in the interest of the US. Will he break up with China? This could be a disaster, as China has so much dollars in their pockets, they could just ruin the US. And even if he is not doing all of that. He is not the guy who stays cool and on top of things. He is super emotional. This is dangerous (in case you want to be the only super power, a.k.a. Empire).
if China stopped investing in US Treasury notes and bills, do you really think that that nobody else wouldn't be having the same thoughts and start unloading their holdings?
I don't think so. If China dumped, the price would fall, raising the effective interest rate. So others would see a really good deal, and buy. In fact, the Fed might just buy it all. $1.185 trillion is about the same as one year of QE2 ($80B/month). It would hurt the USA somewhat, but it would hurt China far more. Not only would they lose billions on their investment, but the weakened dollar would depress American imports, putting millions of Chinese into unemployment.
Did they double-check the mirror this time?
The thing with the Hubble telescope mirror is that engineers at Perkin-Elmer did double-check the mirror with accurate instruments and knew that it was flawed after the figuring was complete. But refiguring it would have cost a lot of money, and delayed delivery (already late), and the improperly assembled null corrector test instrument that was used to figure the mirror was also the contractual acceptance test. So managers and execs and Perkin-Elmer decided to deliver the mirror to NASA anyway, in conformance with contract, without conveying the internal information that the mirror didn't work.
This echos the situation with the Challenger disaster when management at Thiokol decided (after hours of complaint from a very unhappy NASA) to authorize the cold weather launch despite knowing that disaster was almost certain.
Starships were meant to fly, Hands up and touch the sky - Nicky Minaj