2006-01-12, 02:31 | Link #1 |
Disheartened and Retired
Join Date: Jan 2004
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The Astronomy Discussion Thread
I remember there was an astronomy thread, so I searched the forums for astro/astronomy but did not find it. Perhaps it was lost due to the hack incident. Hence, here's a new thread to have casual or critical discussions related to astronomy. Anyways, the news I want to bring is:
The most detailed observation of the Messier object 42 (M42, or more commonly known as The Orion Nebula) has just been completed by The Hubble Space Telescope. Over 100 Hubble orbits, Hubble snapshotted mosaics of M42 amounting to a billion pixels, creating one of the most detailed and largest astronomical image ever released to the public. The resolution is so high that, even spectral M stars (low mass dim red stars) and the even dimmer brown dwarfs (multiple Jupiter mass objects that lack sufficient mass to compress their core enough to initiate fusion), can be seen in the visible spectrum. In fact, the first brown dwarf binary is possibly discovered in this observation. Check out moderately sized images and the full story here. Or grab the image in its full sized glory of 18000x18000 pixels. The full size image has sufficient resolution to make a fine 12ftx12ft print wallpaper (in 300 dpi), according to my friend in photography. 12ftx12ft print wallpaper is much too large, I but think 5ftx5ft of this image in print is splendid enough...ahhhh, beauty isn't it? |
2006-01-12, 03:51 | Link #2 |
Aria Company
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The images taken by the hubble never fail to amaze me.
It's a shame it's future is so uncertain. Though even if NASA does decide to do a repair mission, it won't last forever. I can only hope they seriously consider building a replacement for the hubble. It would be a shame to be left without such a vital tool in our quest to understand the universe.
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2006-01-12, 04:25 | Link #3 | ||
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Quite an ambitious project, its kind of worrisome because unlike the Hubble, we wont be able to service it once it's put out in space, but the ability to view passed the obsticles that have always stood in our way, and truly see into deep space is an amazing feat. I've got my fingers crossed for it, but I can foresee a lot of problems that could easily arise to stop their progress, not to mention ruin it entirly. Imagine if they pulled a Hubble type mistake on this one, and its all the way at the moon. |
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2006-01-12, 05:23 | Link #4 | |
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Hopefully it'll prove to be a worthy successor to the hubble. Looks like it'll be a long wait, but the images this should be capable of will make it worthwhile.
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2006-01-12, 05:32 | Link #5 | |
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Like "tenth planet" http://en.wikipedia.org/wiki/UB313 Even thought Hubble had plenty of troubles, it has expanded our view of universe more than any other single instrument. But maybe it is better to put money to new telescope rather than trying to maintain the old (if it is going to be replaced anyway), NASA is running short of funds, I believe. Also, I don't believe that any of the current manned spacecrafts can reach it, if it is going to be placed 1,5 million km from Earth. But the new shuttles maybe ready at that time too. |
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2006-01-12, 08:15 | Link #6 |
nya`
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Join Date: Feb 2004
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After watching Twin Spica few days ago, the question pop into my mind. Is it true Spica are actually 2 stars? From reference book I only know it was part of Virgo constelation and also known as Alpha Virgo. I'm just wondering if anyone know more?
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2006-01-12, 16:24 | Link #7 |
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Yes, Spica is twin star system. I had to dig some information:
http://en.wikipedia.org/wiki/Spica http://www.glyphweb.com/esky/stars/spica.html Looking that data, Spica makes our Sun look very puny. |
2006-01-13, 10:12 | Link #8 | |
nya`
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Having several moons orbiting your planet is probably interesting to see, but having two suns in the sky that would be quite a sight. Altho it'll be too hot to live in. ^^;; |
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2006-01-13, 18:28 | Link #9 |
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They orbit each other, but not symmetrically, I don't know how things are in reality, but by looking their masses ( heavier star has a mass of 11 sun masses and the smaller one has a mass 7 sun masses), their common point of gravity is near the heavier star, so heavier star makes a smaller orbit. Like if you put a weight of 11 kg on the one end of stick and a weight of 7 kg on the other end, you have to lift it near heavier weight to keep it in balance.
Also, in a few days NASA is going to lauch a fastest probe ever, New Horizons will explore Pluto and other Kuiper Belt objects. Now it looks like the lauch is going to take palce January 17th. After the lauch probe will reach Moon's orbit in just 9 hours (it took couple of days for Apollo spacecrafts to reach Moon) and the probe will travel as fast as 21 km/s (47,000 miles per hour), but it still takes 9 years to reach Pluto, flyby is expected to take place 2015. Website: http://pluto.jhuapl.edu/ |
2006-01-23, 20:11 | Link #10 | |
I am mowing clowns
Join Date: Dec 2005
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National Geographic News has a nice little piece called Hubble's Top Ten Discoveries.
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I've also been quite fascinated with the SOHO (Extreme ultraviolet Imaging Telescope) work: -> http://umbra.nascom.nasa.gov/eit/EIT.html -> http://soho.nascom.nasa.gov/ -> http://umbra.nascom.nasa.gov/eit/eit_full_res.html |
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2006-01-24, 11:21 | Link #11 |
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Just a question, who was the first to discover that a stars position is not what we look at every night ? I mean the nearest star is light years away right ? so what we see every night at a star is the image of that star like many years ago... Can someone please tell me who was the first to discover that ? PLEASE BE 100% SURE!!
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2006-01-24, 11:47 | Link #12 |
Paranoid Android
Join Date: Dec 2005
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I’ll jump into this thread..
I want to buy one telescope of good quality. I am a beginner in astronomy, and want to make this one of my hobbies. I’ve heard that Meade has good models, so I went there and there are a lot of choices between reflectors and refractors. I’m willing to spend around U$ 300 on it. Any advices? |
2006-01-24, 22:41 | Link #13 | ||
Disheartened and Retired
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2006-01-25, 13:41 | Link #14 | |
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Ahh....more new planet goodness.
Scientists spot a new Earthlike planet Quote:
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2006-01-25, 14:09 | Link #15 | |
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Still, 5.5 times the earth's mass doesn't seem very "earthlike"... Though I guess it's a lot closer than the planets several times the mass of jupiter.
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2006-01-25, 17:27 | Link #16 | ||
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2006-01-25, 21:49 | Link #17 | |
ロリ is life~
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2006-01-26, 02:22 | Link #18 | |
Disheartened and Retired
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For your interest (FYI): We are able to measure differences in light intensity (photometry) quite accurately. Canada's MOST telescope (nicknamed "The Humble Space Telescope", and somewhat modeled after Spongebob Squarepants) does this job extremely well. Imagine the city of Toronto at night, and all the lights are on in that city. Turn off one light. MOST is able to measure that difference in intensity of light coming from Toronto. My astronomy 201 professor last semester, Dr. Jaymie Matthews, was actually involved in the construction of this telescope and heads the MOST project. He has a colorful background as an astronomer and professor... The Hipparcos satellite, however, is able to measure parallaxes down to about the 1 milliarcsec range (1/1000ths of an arcsec [denoted "]; 1" = 1/60' [arcmin] =1/3600°). Let's put this in more tangible words. Imagine a person in front of you about 3 meters away. Wait ten seconds. In that ten seconds, that person's hair has grown about 1millarcsec with respect to your position, and the Hipparcos satellite can measure that angle. Last edited by Muir Woods; 2006-01-26 at 12:17. |
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2006-01-26, 13:34 | Link #19 |
I am mowing clowns
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Here's an interesting article that takes on some of the myths surrounding the Challenger shuttle disaster.
As a side note: I did watch this event "live". I was in Grad school at the time and had the day off. I was with two other college friends at my house and we were all watching the Challenger launch on CNN and saw the disaster that followed. I'll quote the myth and a bit of the write up (no need to quote the enitre story). There's more to the story (and the myths), so follow the link below if you're interested. I found it to be quite interesting, but then I was very much alive at the time it happened. ------------------8<---------------- 7 myths about the Challenger shuttle disaster It didn't explode, the crew didn't die instantly and it wasn't inevitable Myth #1: A nation watched as tragedy unfolded Few people actually saw what happened live on television. The flight occurred during the early years of cable news, and although CNN was indeed carrying the launch when the shuttle was destroyed, all major broadcast stations had cut away — only to quickly return with taped relays. Myth #2: Challenger exploded The shuttle did not explode in the common definition of that word. There was no shock wave, no detonation, no "bang" — viewers on the ground just heard the roar of the engines stop as the shuttle’s fuel tank tore apart, spilling liquid oxygen and hydrogen which formed a huge fireball at an altitude of 46,000 ft. (Some television documentaries later added the sound of an explosion to these images.) But both solid-fuel strap-on boosters climbed up out of the cloud, still firing and unharmed by any explosion. Myth #3: The crew died instantly The flight, and the astronauts’ lives, did not end at that point, 73 seconds after launch. After Challenger was torn apart, the pieces continued upward from their own momentum, reaching a peak altitude of 65,000 ft before arching back down into the water. The cabin hit the surface 2 minutes and 45 seconds after breakup, and all investigations indicate the crew was still alive until then. What's less clear is whether they were conscious. Myth #4: Dangerous booster flaws result of meddling The side-mounted booster rockets, which help propel the shuttle at launch then drop off during ascent, did possess flaws subject to improvement. But these flaws were neither especially dangerous if operated properly, nor the result of political interference. Each of the pair of solid-fuel boosters was made from four separate segments that bolted end-to-end-to-end together, and flame escaping from one of the interfaces was what destroyed the shuttle. Myth #5: Environmental ban led to weaker sealant A favorite of the Internet, this myth states that a major factor in the disaster was that NASA had been ordered by regulatory agencies to abandon a working pressure sealant because it contained too much asbestos, and use a weaker replacement. But the replacement of the seal was unrelated to the disaster — and occurred prior to any environmental ban. Even the original putty had persistent sealing problems, and after it was replaced by another putty that also contained asbestos, the higher level of breaches was connected not to the putty itself, but to a new test procedure being used. “We discovered that it was this leak check which was a likely cause of the dangerous bubbles in the putty that I had heard about," wrote physicist Richard Feynman, a member of the Challenger investigation board. Myth #6: Political pressure forced the launch There were pressures on the flight schedule, but none of any recognizable political origin. Launch officials clearly felt pressure to get the mission off after repeated delays, and they were embarrassed by repeated mockery on the television news of previous scrubs, but the driving factor in their minds seems to have been two shuttle-launched planetary probes. The first ever probes of this kind, they had an unmovable launch window just four months in the future. The persistent rumor that the White House had ordered the flight to proceed in order to spice up President Reagan’s scheduled State of the Union address seems based on political motivations, not any direct testimony or other first-hand evidence. Feynman personally checked out the rumor and never found any substantiation. Myth #7: An unavoidable price for progress Rationalizations that the disaster was the unavoidable price to be paid for pioneering a new frontier were self-serving cover-ups of those responsible for incompetent engineering management — the disaster should have been avoidable. NASA managers made a bad call for the launch decision, and engineers who had qualms about the O-rings were bullied or bamboozled into acquiescence. The skeptics’ argument that launching with record cold temperatures is valid, but it probably was not argued as persuasively as it might have been, in hindsight. ------------------8<---------------- |
2006-01-26, 16:23 | Link #20 |
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That was indeed very interesting, before this I had thought that NASA was under some pressure to lauch the shuttle. I vaguely remember the disaster, of course I wasn't watching it live, but it was on the news as soon as it happened.
Sadly, accidents happens, no matter what you do, but not listening warnings and then learning nothing from the disaster and trying to cover their own asses is just low. What is more amazing that the Columbia disaster wasn't handled much better. |
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