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My personal experience is that even the largest and most sensitive AO system in the world (NIRC II on Keck II with laser guide star) still really struggles make an observation in 20 minutes that Hubble can do in 5 minutes. If anyone were to launch a >3 m aperture visual-band space telescope (NOT JWST, that's IR), it would blow all these AO systems out of the water.

Yes, but "Hubble resolution, at a price" makes it sound like Hubble was the expensive one.

From its original total cost estimate of about US$400 million, the telescope had by now cost over $2.5 billion to construct. Hubble's cumulative costs up to this day are estimated to be several times higher still, roughly US$10 billion as of 2010.

Compared to that, the Magellan telescopes

Total annual costs $10,437,639

That figure is including amortization of the $73 million dollar ($3,665,250*20) investment so $200 million total over 20 years. This means you can get 50 AOs for the cost of one Hubble, now which one comes "at a price" again?

Yes, NRAO and NOAO are very different and in charge of different things.

But contrast NRAO's initial response (here) to that of NOAO (here) or even AURA (here, sorry its a PDF) to see the different approaches that are possible.

NRAO essentially criticize the portfolio review process and reject the results outright without consideration and essentially hopes that the NSF figures out a better way: "AUI and NRAO encourage the NSF to work with its other federal agency counterparts to consider a more balanced approach with additional funding scenarios for the entire U.S. federal astronomy portfolio." Compare that to NOAO's response which creates an online discussion point, lays out specific details about each relevant point, encourages all astronomers to talk to their congress people, as well as making observations about the situation between NRAO and ALMA being similar to NOAO and LSST.

This isn't a time to complain about losing one or two specific facilities, this is a time for talking about the entire picture of how bad this would really be if divestment goes through and facilities are either closed or put into private (closed) consortiums. NRAO's response honestly comes across as sour grapes defending their own stuff with little concern of the greater picture.

If you don't mind driving up long, windy roads and turning off your cell phone, the National Optical Astronomy Observatory has a visitor center at Kitt Peak -- they have a bunch of telescopes there, including a solar telescope, so it's possible that they might be observing if it's not too windy. (it was too windy when I went there).

http://www.noao.edu/outreach/kpoutreach.html

Maybe this change is a Y2K style jobs program. Nah, too few types of code are affected. It's not like my bank needs UT1 or barycentric dynamical time to the microsecond.

Y2K was a non-millennial event precisely because squadrons of crack programmers were deployed to fight the good fight. A Y2K inventory such as: http://iraf.noao.edu/projects/y2k/y2kplan.html, was a relatively straightforward exercise in pattern matching, but still required the examination of the entire codebase.

A similar UTC-clean inventory will be needed against a similarly broad codebase. It will not be a simple exercise in pattern matching. The assumption has been that whole industries and communities can ignore the whole thing. This assumption results from viewing the issue as being about ceasing leap seconds.

Rather, like the curious incident of the dog that didn't bark, the absence of leap seconds has broader implications, namely UTC will no longer be a type of universal time. Rather than simplifying civil timekeeping, suddenly two types of time must become explicit in the source and libraries of diverse systems that previously could assume they were the same thing.

Banks may not need "UT1 or barycentric dynamical time to the microsecond". But the error will accumulate six orders of magnitude larger than that annually, and many of the systems funded by the banks - air, land and sea transportation, GIS, communications, logistics in addition to science and tech - may certainly care.

The point is - nobody has looked. This is Y2K under an invisibility cloak.

Astronomy indeed.

Firstly, amateur observation is an awesome hobby. But beyond that, there are areas where professional astronomical research depends on amateur observations. For example, research about variable stars requires numerous observations over time. You can read about this at the American Association of Variable Star Observers website. You may also want to see if there is an amateur observing group near you (there probably is). This is a great contact to establish since they will have considered many of the questions you're going to encounter, and since it's always fun to talk to others who share your interests.

A few more words about astro research since my undergrad degree was in astronomy. A good telescope does a lot to expand the targets you can observe and a good CCD and filter set does wonders for the data you can take...but you can do interesting things ranging from naked eye on up. There is also a lot of publicly-available astronomy data which you could do analysis on, either because the observer chose to publish it or because it came from public sources. More than anyone will ever have time to exhaust. Learn how to work with it and keep good records of your reduction and analysis process. IRAF is one of the main tools here - and it's FOSS, as are a number of other useful tools. For understanding existing data files or for taking your own observations, Steve Howell's "Handbook of CCD Astronomy" is a good read. It helps if you can program at some level, although you can always pick that up.

More broadly, what's the difference between hacking together something interesting and doing scientific research? Mainly, it has to do with what you do afterwords in order to test your results, the rigor with which you approach the capture and analysis of data, and how you go about framing and presenting what you did when sharing it with others. Depending on what you want to do, maybe that requires a bit of extra equipment, and certainly it involves a lot of extra time, thought, and probably training. But the added expense is not always prohibitive, or even usually. Not every research project has to be run on a high-energy supercollider or on a top-tier computing cluster. Academic research projects have to worry about facilities costs, stipends for graduate students, et cetera...you as a hobbyist do not. You can also often gain access to articles in academic and professional journals by visiting your local college campuses - their libraries will usually make these available to anyone who cares to come in and use them. This will be no end of helpful when trying to understand what has already been done and how.

What you will be missing as an amateur is the support network surrounding an academic or industrial researcher, and the experience which you can get by working for and with more experienced researchers. This is the main thing which will limit the contributions you can make, not your access to facilities and equipment. But what is your real goal here? Do you want to explore and have fun, and maybe share some results in a way which inspires your fellow researchers? Is getting credit through publication in a formal journal even important to you since that's not your career? Do cool things, take risks, explore! It's 2010 and a new frontier thanks to the internet - you can publish to a blog or on Youtube. Interesting results will get picked up on sites like Slashdot or Hack a Day, people will see them, "real" researchers will see them. If you do interesting work and present it in "scientific" way, it can be a real contribution to humanity. And it will be fun!

First, there is no proof there's a conspiracy to deny publication of dissenting papers. Several investigations have decided that there is no conspiracy. There is an outside chance that one little corner of science may have slipped into pseudoscience, but that's hardly justification for your statements about science in general.

The nondisclosure of data is a serious issue, but it's also not universal and even in this case it sounds like it's more due to the CRU not having the legal right to disclose the data in question, NOT to their unwillingness to do so. That's a problem with the law or with the commercial right-holders, not science. Again, even in the worst case scenario, it's not a justification for your statements about science in general.

Following are a few examples of large, publicly available scientific datasets that were assembled at considerable cost, entirely voluntarily (a small selection, several that I have personal experience with and others that I've included to try to give some breadth to the list):

http://physionet.org/
http://mouldy.bic.mni.mcgill.ca/brainweb/
http://www.med.harvard.edu/AANLIB/home.html
http://archive.eso.org/skycat/servers/usnoa
http://www.astrometry.net/data.html
http://www.ncbi.nlm.nih.gov/genbank/GenbankOverview.html
http://www.ncbi.nlm.nih.gov/guide/data-software/

And some publicly available code:

http://noodles.bic.mni.mcgill.ca/ServicesSoftware/HomePage (the MINC tools are apparently available from Debian as well)
http://www.bic.mni.mcgill.ca/~ilana/diffusion/diffusion_tools.html
http://www.vlfeat.org/~vedaldi/code/sift.html
http://www.itk.org/
http://www.cs.cmu.edu/~cil/v-source.html
http://iraf.noao.edu/

There's hardly an overwhelming culture of closed and proprietary secret keeping in science as you suggest. Quite the opposite. Sure, some of the non-scientific appendages to science do have issues in that area (journals, for example) but scientists are usually all too willing to do end runs around such things. If you want to read a paper, e-mail the author and he's likely to send you a PDF despite that often being technically a violation of copyright. Failing that, go to a library and they'll let you read it, free.

go to Kitt Peak

See here, for example, for more information.

There are wavelength ranges in the NIR where the atmosphere is indeed transparent (J,H and K bands, for example); but the atmosphere is opaque at most NIR wavelengths (and, even at those IR wavelengths where the atmosphere is transparent, the transmittance is lower than at visible or radio wavelengths). See here for more info.

Now, as to his claims, there are many. Most, if not all, seem to me to rely on his concept of "gravitational transverse redshift" GTR, which in turn (he claims) follows from "a simple thought experiment" on slide 6 of his first lecture, "A Correction to the Gravitational Model". A little though shows his conclusions on slides 6 and 7 to be incorrect. If A sees B's clock running slowly and B sees A's clock running slowly this leads inevitably to a contradiction - an inescapable paradox.

Say both A and B set their clocks simultaneously to zero, according to an observer at rest at a point O, halfway between A and B, while the spacecraft is at rest. The observer at O also sets their clock to zero at the same time. At this point both Mayer and Einstein would say that all three clocks are observed by A, B and O to be running at the same rate.

Let the spacecraft accelerate at rate g for t seconds according to the clock at O, which continues to be halfway between A and B. Then let the spacecraft coast - becoming an inertial frame again. Now all three clocks are again observed to be running at the same rate. According to Mayer though, O sees the clocks at both A and B to be lagging the clock at O, A sees the clocks at O and B to be lagging the clock at A, B sees the clocks at O and A to be lagging the clock at A.

We now move the observers and clocks at A and B to the location of O, taking great care to do so completely symmetrically, so that there is no reason to distinguish between A and B. Here is the paradox - according to Mayer, A continues to see B's clock lagging A, and B continues to see A's clock lagging B.

This is not the same as the twins paradox. According to O, who has been sitting in the middle all this time, the movement of A and B has been completely symmetrical and there is no reason to favour one over the other.

Since the rest of Mayer's argument, especially GTR, seems to me to depend on this thought experiment, and since his conclusions from the thought experiment are wrong, his remaining theoretical arguments will fall, unless they follow from other principles.

It looks like heavier elements (past Iron) were largely formed earlier in the history of our galaxy. As best we can tell, the first stars to form in our galaxy were supermassive stars that quickly went supernova. Then we see stars with masses 8-10 our sun going supernova and creating more heavy elements.

Eventually we see stars with masses 3-7 times the sun which create strontium, barium, and some lanthanides, but not by supernova.

Finally up until 10 billion years ago, it looks like supernovae from white dwarfs was responsible for adding more iron to the galaxy. The article I got this from (http://www.noao.edu/outreach/press/pr00/pr0004.ht ml) indicates that the current epoch shows a gradual addition of Lithium but the source is unknown.

I am not an astrophysicist, but it seems to me that given that there is no stable isotope at mass 5, the only ways you could get to mass 6 or 7 is either by beta decay from mass 10 or 11 (most likely Boron, though Boron 10 and 11 are both pretty stable) or by fusing Helium-4 with Hydrogen-2 (as a final and perhaps trace stage of the PP chain). Lithium-6 could then fuse with Hydrogen-1 to become Lithium-7. The other option might be for larger stars (red giants) to create, as an alternative to the triple alpha capture resulting in Carbon, a two-alphas and a Hydrogen2 capture resulting in Boron-10 (through the same beta decay which is involved in creating Hydrogen-2 from two protons). Boron-10 could alpha decay into Lithium. It seems that these are the only two logical ways that Lithium could be created at masses of 6 and 7. I would argue that the former mechanism seems far more plausible than the latter. Lithium could then be fused with another alpha to create Boron where necessary. In this model, Lithium 6 and 7 become the precursors to Boron 10 and 11, and probably don't relate much to anything else.

Milky Way won't collide with another galaxy for several million more years, when Andromeda MAY hit us.

Don't panic! That's billon, not million:

http://www.space.com/scienceastronomy/astronomy/ga laxy_collides_020507-1.html

Reassure your children:

http://www.nasa.gov/audience/forstudents/5-8/featu res/F_When_Gallaxies_Collide.html

Don't show them messy pictures like this:

http://www.noao.edu/outreach/current/collide_hilit e.html

SOAR appears to be still in a commissioning phase, so it would be easier to get time on the telescope.

Other ways to get fast time on a telescope: queue scheduling; calling a friend who has time that night; just happening to be there at the right time.

SOAR appears to be still in a commissioning phase, so it would be easier to get time on the telescope.

Other ways to get fast time on a telescope: queue scheduling; calling a friend who has time that night; just happening to be there at the right time.

Hardly. Consider the following, slightly unrelated tale. It demonstrates how LITTLE can happen in 13 billion years. English prose uses 26 lower-case letters and 26 upper case letters. Throw in 10 digits, and the following 18 common pucntuation marks: .!?,;:'"$#%&()/-+* and we get roughly 80 characters ( 26+26+10+18=80 ) that are used in common english prose. This is conservative considering that most modern keyboards have 100+ keys. For our purposes, we will say that one monkey pressing one key will therefore have a chance of 1 in 80 of typing any particular letter, say T. One monkey pressing two keys will have a chance of 1/80 times 1/80 of typing any two particular letters, say Th. That is, a monkey has a chance of 1 in 6400 of randomly typing "Th". To type the word "The", the chances are 1 in 512000 (1/3^80). In general, for N characters, the probability would be 1/N^80. Now let's examine a longer sentence: "The quick brown fox jumped over the lazy dog's back." This sentence has 52 characters. So the probability of monkey typing this in randomly is 1/52^80. Or, 1 chance in: 19066346913841944036898935159067571914007532772132 2538326368101913940\ 54066195372127089220252400916515660459655214049797 8921601884724658176 That looks like a pretty big number. That's 138 digits. Or in scientific notation, about 2 x 10^137. Let's say our monkey could type one character per second (he's very coordinated and very disciplined). How long would it take to type 19066346913841944036898935159067571914007532772132 2538326368101913940\ 54066195372127089220252400916515660459655214049797 8921601884724658176 characters? Well, there are 60 seconds per minute, so this would be: 31777244856403240061498225265112619856679221286887 089721061350318990\ 09011032562021181536708733486085943409942535674966 315360031412077636 minutes. Or, with 60 minutes per hour: 52962074760672066769163708775187699761132035478145 149535102250531650\ 15018387603368635894514555810143239016570892791610 5256000523534627 hours. Or, with 24 hours per day: 22067531150280027820484878656328208233805014782560 478972959271054854\ 22924328168070264956047731587559682923571205329837 719000021813942 days. Ok, there are 365.25 days per year, so that's: 60417607529856339002011988107674765869418247180179 271657657141833960\ 92879748577878891050096458829732191440304463599829 483915186348 years. Now, the universe is about 13.7 billon years old ( http://www.space.com/scienceastronomy/map_discover y_030211.html ). That's 13,700,000,000 years. So how many ages of the universe would it take that monkey to enter that many characters? Oh, only: 44100443452449882483220429275675011583516968744656 402669822731265664\ 91153101151736416824887926153089190832339024525422 98 AGES OF THE UNIVERSE. That's a long time for one monkey to be working on that one problem. So let's put more than one monkey to work. Hmm, how about one monkey per atom in the universe (these are very small monkeys). For our purposes, we can estimate the number of ATOMS IN THE UNIVERSE to be 4 x 10^78 ( http://www.sunspot.noao.edu/sunspot/pr/answerbook/ universe.html#q70 ). So, using 4 x 10^78 monkeys, how long would it take all of them? Ok, this is getting better. Only: 110251108631124706208051073189187528958792 AGES OF THE UNIVERSE. That's still a big number, about 10^41. Well, maybe the monkeys could work faster than one character per second. Maybe a monkey could work as fast (or faster than) today's modern desktop CPU. Let's be generous and say 10 GHz (10,000,000,000 operations per second,

Just an interesting tidbit, it has not rained in the Atacama desert for 100s of years.

As others have pointed out, it's only some parts of the Atacama that haven't had rain in hundreds of years. It stretches from the coast to the Andes, so it's big enough for some rain to occur.

In fact, a wonderful event happens every once in a while. Some seeds remain dormant in the sand, and when it rains, they are revived, and thousands of flowers suddenly blossom covering large patches of desert. We call it "desierto florido" (the flowering desert, look it up, here's an english link). It's really quite remarkable.

- PeeCee

And from Wikipedia:
"Moore's law is an empirical observation stating, in effect, that at our rate of technological development and advances in the semiconductor industry, the complexity of integrated circuits doubles every 18 months"

Hence, it can't be a law.The law of gravitation isn't going anywhere any time soon.

Please read my post again. There is no law (of physics) that is not based on empirical observations (including the law of gravity), and thus it's pointless to point out that this particular law is.

Meanwhile, nothing prevents AMD and Intel from stopping the improvement of their processors.

Something does. Namely, AMD is stopped by Intel and Intel by AMD. In this particular instance, capitalism seems to be working pretty well.

Besides, it doesn't even say anything about computing power, but the number of transistors.

Actually, the quote you showed speaks of complexity; better to speak of it, since we might switch to light/quantum computing soon enough, at which point the word "transistor" is going to be obsolete.

In any case, the number of transistors directly translates to computing power (barring any truly stupid design decisions), because two transistors can do twice the information handling in a time unit than one transistor could.

Parallel processing or not, the fact remains that it is possible to make a key long enough so that while a computer will be able to use it easily, the power of the entire universe, with each atom operating at 100 GHz for longer than its current age won't be enough to search the whole keyspace.

The number of (hydrogen) atoms in the universe is estimated to be at least 4 * 10^78 by http://www.sunspot.noao.edu/sunspot/pr/answerbook/ universe.html. This means that, if the work is divided evenly, each atom would have to search through 2^128 / 4 * 10^78 keys. 2^128 is a bit over 3.4 * 10^38, which is much smaller than the number of atoms in the universe, so the time to search the whole keyspace would take as much time as it takes to check a single key by a single atom processor.

2^256 is about 1.2 * 10^77, which would still fail to give a key to each atom of the universe.

But, of course, there's nothing stopping one from just adding bits to the key...

http://www.sunspot.noao.edu/sunspot/pr/answerbook/ universe.html

Says that there are "at least about 4e78, but perhaps as many as 6e79" atoms in the universe, while 2^128 = 3,4e38. But 256 bit would be enough. :)

Ground based astronomy isn't as sexy as space based astronomy, but has one big advantage -- light gathering power. We can build 8-meter (SUBARU and GEMINI), 10-meter (KECK), and in the near future 30 to 50-meter telescopes. The JWST, by comparison, is only 6.5 meters, and that's still 7 years away (at least). It's expensive to get telescopes into orbit, first off, and to send a probe up, well, you only get one look at the system with that! Additionally, launching anything drives the cost up by tens of millions of dollars. Ground based telescopes are easier to service, last virtually forever, and only have the disadvantage of having the atmosphere to fight with. Adaptive optics, and camera technology have significantly advanced in recent years, so that ground based telescopes with adaptive optics have huge advantages over those without it. They haven't caught the space telescopes yet, but the gap is closing. I'm a huge advocate of hubble, chandra and other space-based missions, but what can be accomplished on the ground (such as this) should NOT be overlooked!

• 38 inches according to a page at Arkansas State University and another at Microflex Technologies. Well the conversion (1 meter = 38 inches) is mentioned actually by some apparently russian website which is linked on this page at the arkansas state university
• 38.16 inches according to a rounding-happy math teacher at Norfolk Collegiate School in Virginia.
• Couldnt test this one, because the website was down (probably slashdotted)
• 38.37 inches according to Honeywell's Sensotec folks.
• Ok, well, this is indeed incorrect. However, on the same PDF it is mentioned that 1 inch = 2.54 cm, 1m = 1.0936 yards, which are both correct values. So I seriously believe that (1 m = 38.37in) is just a typo and should have actually been 1m=39.37 in.
• 38.8 inches according to some numerological babble
• Well, if it is "babble",then why consider it at all?
• 39 inches according to Fife Products and some folks who sell quilting products.
• That makes sense, doesn't it? Quilt and other such manufacturers would want to save on by "trimming" or low-rounding such conversions wouldnt they? For selling 1000m of their product, they save 37 inches!
• 39.14 inches according to the specifications on a measuring wheel for engineers. (uh-oh!)
• This does look incorrect. I can't think of why they'd equate 1m=39.14 inches.
• 39.15 inches according to an October 30 2002 entry in a blog.
• Why would you be concerned about what's on a blog. People put whatever they want to.
• 39.21 inches according to Richard Bowles.
• Again, who is richard bowles? I've no idea.. do other slashdotters know? Even if he is an authority on metric systems, why would you use an individual's figures as a source of reference? Would you not prefer to look at a metrics standards body or other such resource?
• 39.27 inches according to pages at University of Wisconsin Stevens Point and the National Optical Astronomy Observatory.
• On the same page you'd notice: "Since many of our students travel to Europe or Australia, we've prepared the chart below to show you how to estimate foreign measurements. We hope you find it helpful:"...Did you notice the word "estimate"? Well, if anything, it wasn't at helpful to you I presume :-)
• 39.28 inches according to Jonathan Brooks at Penn State University.
• Again, I think this "Jonathan Brooks" is a user/student at Penn State University, and this URL you posted isnt an authoritative advisory from the University itself.
• 39.3 inches according to some

This evening, I learned that one meter equals 39.3700787 inches. While this may come as no surprise to some people, it was one to me - for years, I had mistakenly believed a meter was 39.77 inches, and now I know it's basically 39.37.

Of course, I'm not alone in my confusion. A bit of research on Google revealed quite a few different conversions from meters to inches. Here are some of them:

• 38 inches according to a page at Arkansas State University and another at Microflex Technologies.
• 38.16 inches according to a rounding-happy math teacher at Norfolk Collegiate School in Virginia.
• 38.37 inches according to Honeywell's Sensotec folks.
• 38.8 inches according to some numerological babble
• 39 inches according to Fife Products and some folks who sell quilting products.
• 39.14 inches according to the specifications on a measuring wheel for engineers. (uh-oh!)
• 39.15 inches according to an October 30 2002 entry in a blog.
• 39.21 inches according to Richard Bowles.
• 39.27 inches according to pages at University of Wisconsin Stevens Point and the National Optical Astronomy Observatory.
• 39.28 inches according to Jonathan Brooks at Penn State University.
• 39.3 inches according to some laser folks.
• 39.34 inches according to a page about photography, and another about a role-playing game. Hey, it's only a game, their meters can be whatever length they want.
• 39.36 inches according to some ham radio sorts and some NASA folks among others. Pretty close... but... shouldn't NASA know better by now?
• 39.38 inches according to people who race 1-meter model yachts, talk about prehistory in California, and, um, other NASA folks. Again, pretty close!
• 39.39 inches according to someone ranting against metric (how ironic), as well as a page about UFOs.
• 39.4 inches according to a list of conversions from a company that makes electric motors and such things, and the Secretary of the Navy.
• 39.45 inches according to a set of math problems f

the telescope/instrument control systems are/will not be linux, as far as i know, but the data will be archived and reduced on linux (some reduction might also be on suns and max osx).

i work at ctio, writing iraf software for noao - iraf is multi-platform, but we develop on linux (currently red hat, about to move to fedora, although i also have it running in debian on my laptop - well, i did until yesterday, when i messed up a kernel recompile/install and lost linux completely (it's an x31, so i need to do a network boot to get it back etc etc) :o)

Blue of course! The night sky is the same color as the day.

Here is a night-sky spectrum at Kitt Peak. Note the OH emission in the red. Also important is sodium light pollution ("Na D" and "HPS") even well outside the nearest city.

Hope that was useful.

I thought I'd introduce some more facts into the discussion. There were, until recently, two major independent efforts to develop a 30 m optical/IR telescope:

• The California Extremely Large Telescope project, brought to you by the same folks responsible for the Keck telescopes - that is, the University of California and Caltech.
• The Giant Segmented Mirror Telescope project, by the National Observatories, headquartered in Arizona.

As part of this, both groups applied for about $35M of funding for the next stage of the development, which will involve doing more detailed design studies, simulations, and construction of subsystem mockups to test performance. The plan is after about three years of this to have a completed design and then be able to break ground around 2008 or so, and become operational around a decade from now.

Incidentally, NOAO asked for their $35M from the National Science Foundation, while the UC/Caltech team approached the Moore Foundation, Gordon Moore's philanthropic organization. So a tiny fraction of every dollar you spend on an Intel chip may someday help to make this telescope a reality!

The current concensus seems to be around 10e80 atoms.
A 70kg human will have around 7e27 atoms.

this magnificent galaxy is nearly one-fifth the diameter of the full moon

This reminds me of an image I seen lately, here.

It was really a suprise to learn just how big these objects are in the sky despite the unimaginable distance. That and just how dim they are! Even our own galaxy is a faint band of light despite us being right inside it. It's a shame really, imagine seeing the Andromeda galaxy like in that picture high in the sky!

Definitely, the Very Large Array radio telescope outside Socorro, New Mexico. Also Kitt Peak National Observatory,/a>.

Parent may be Trolling, but I'll bite.

Get some on who can talk on your level to tell you about relativity and then maybee youll understand why we dont send manned missions to jupiter.

I'll confess right away that my knowledge of Einstein's physics is extremely limited. I've allocated those brain cells to the Grammar, Punctuation, Spelling and Capitalization Department. :) But what would it be about Relativity that would preclude a manned mission to Jupiter?

Yes, the speed of light would cause a huge latency in communications -- anywhere from 35 to 51 minutes according to these calculations. But that's hardly a restriction. The communications lag between Europe and the Americas was measured in months, and that didn't prevent exploration and migration (though it sure made it tough). On the other hand, it does make it hard to teleoperate a robotic craft... an awful lot can go wrong in an hour. Is "meltdown" even an appropriate term when there is no "down"?

The only other effect of relativity I can think of would be the part where the faster you go, the slower time is. That's a huge over simplification, I know! But I believe this effect is negligible over non-relativistic speeds -- and we're not looking at anything approaching the speed of light for a trip to Jupiter.

Besides, while the proposal bounced around in the article and discussion is about a Jupiter mission, there's no reason the first nuclear-powered space flight must be (or even should be) to a far-away destination. Just fly around the moon a few times, or something. :)

Or did you mean the kind of "relativity" that happens around the table at Thanksgiving?

At NOAO the Unix lpd has long been used as the mechanism for Save the Bits, which is the means by which they and several other observatories archive all of the data acquired at their telescopes.

At NOAO the Unix lpd has long been used as the mechanism for Save the Bits, which is the means by which they and several other observatories archive all of the data acquired at their telescopes.

I don't think the big profs count the 2.2 and 3.6 meter telescopes as a top tier toy. As an undergrad at Arizona I had regular access to a 2.3 meter and a 2.4 meter telescope on Kitt Peak immediately after my freshman year. Part of this was due to having a nice advisor and some of it was because everyone else was trying to use bigger telescopes like the MMT and Magellan.

Seeing as this guy is at Hawaii I'm betting the fights over the 2 to 3 meter class telescopes is no where near the fights people would get into over the much bigger (10 meter class) WM Keck telescopes

And after only an undergrad degree I have a cushy job in astronomy at the SIRTF Science Center that pays more than some astro postdocs. . . .

No, but I could exceed the speed of light via a poor explanation really easily.

Want to get to Alpha Centauri in, say, a year? No problem - that's about gamma = 4, or about 0.97 c. Of course, someone not familiar with relativity would say that you're travelling at 4c, but that's because of an improper definition of distance - in truth, you only traveled 1 light year, not 4 - the distance Lorentz-contracts.

Same situation here. Standard stupid way of calculating speeds against the sky don't work because your estimation of what the distance travelled is is wrong. It's just geometry.

Here for the math. You're not tacking. It's assuming that a distance in one reference frame holds in another, highly relativistic frame.

There are plenty of places to attack standard current astrophysics: the measurement of the fine structure constant changing? Very weak. SN 1a distance determination? A little odd, considering we don't really understand all the classifications we have. But superluminal motion is just a reference frame mistake.

There's a lot of information available at the page linked to by the /. post. It's dense, though. Readers might find this page a little easier to digest.

Yes, that is interesting indeed.

I think in general there may be interesting research to be done in the area of mapping/visualization of complex data: for instance this project of mapping the internet.

Does this really help in general? Are there many cases where such visual maps would help understanding of complex data?
Think for example, it may be interesting to produce such a map of everything2, which is a sort of hyperlinked online encyclopedia, to see where the clustering is.

In astrophysics, 3D maps of the universe have been produced for some time, and the human-eye understanding of large-scale structure was at first more direct than statistical analysis--for instance, people would see the famous filaments, but stats wouldn't.

A post above quoted the possible use in spotting "usefulness" of code contributions, by looking at their interdependencies for example.

Tcl runs the operator interface of Shell Oil's Auger, a drilling rig in the Gulf of Mexico. See pictures of the rig here, and read about the system integrators here.

Don't like oil rigs? Well, it's highly unlikely that you can mod this post down without the Tcl that's built into practically every Cisco router on the planet. Read Cisco's tesimonial.

Once you've done that, go log off and watch TV. Oh yeah, did you know that the NBC network control system is a Tcl application? It is; it's been in the digital broadcast system from prototype all the way to full 24x7 operation. ComputerWorld ran an article about the project.

Science geeks will be interested that a Tcl interface is used to program the Hubble Space Telescope

Database heavies will be intrigued by the intimate role that Tcl has in Oracle Enterprise Manager.

I could go on all evening, this is just the tip of the proverbial iceberg.

All of these measurements are made under the purview of the International Earth Rotation Service. There are models for all manner of astrophysical and geophysical effects considered in the Conventions that are used when reducing the data.

The way that solar noon is kept at civil time noon is by inserting leap seconds. In most places civil time is offset directly from UTC. When a leap second is inserted the day is 86401 seconds long.

This irregularity upsets some kinds of timekeeping systems, and as a result there has been discussion that leap seconds should be abolished. That would cause noon to drift away from noon. That may not be a good thing.

Yes, that is interesting indeed.

I think in general there may be interesting research to be done in the area of mapping/visualization of complex data: for instance this project of mapping the internet.

Does this really help in general? Are there many cases where such visual maps would help understanding of complex data?
Think for example, it may be interesting to produce such a map of everything2, which is a sort of hyperlinked online encyclopedia, to see where the clustering is.

In astrophysics, 3D maps of the universe have been produced for some time, and the human-eye understanding of large-scale structure was at first more direct than statistical analysis--for instance, people would see the famous filaments, but stats wouldn't.

A post above quoted the possible use in spotting "usefulness" of code contributions, by looking at their interdependencies for example.

The total number of Space Shuttles that ever left the ground is now six. The first one, Enterprise, could not lift off on its own and was instead launched from the back of a Boeing 747 airplane and then glided to the ground. The other five Space Shuttles (Columbia, Challenger, Discovery, Atlantis, and Endeavor) have been launched into space. The Challenger exploded just after takeoff on January 28, 1986, but the other four orbiters are still in use.

The loss of Mt. Stromlo Observatory facility is very great loss.

A number of the obvious sites related to Stromlo are down, due to the fire or due to the wide spread power outages in the area. I will make links to indirect and cached pages.

Established in 1924, the Commonwealth Observatory at Mount Stromlo, on the outskirts of Canberra. Commonwealth Observatory was recognized for its important research into the origin and future of the universe.

Astronomers at Mount Stromlo made outstanding contributions to astronomy. It would be difficult to list all of the important contributions to Astronomy made by the people working at Mt. Stromlo. Now, a few come to mind:

• Stromlo research in the 1950s provided the first clue that the Magellanic Clouds had evolved differently from our own galaxy. These results gave us important insights into galactic evolution.
• In the 1990's, astronomers from Stromlo and Sliding Springs (many km away from the fire area) showed that about 90% of disc galaxies (such as our own) are greatly influenced by ''dark matter'', in their galaxies' halos.
• They made important observations in the first hours after Supernova 1987A (the first naked eye supernova in several centuries of years) was discovered.
• Then there is the sort of work such as the Stromlo Abell Cluster Supernova Search
• The Massive Compact Halo Objects (Macho project that was the first to record many microlensing events in our Galaxy as well as in the LMC.
• Then there was all of that tedious, but vital work of spectral classification of southern stars.
• Many of the first parallax distances to Southern stars were first made at Stromlo.
• The list goes on and on ... I am sorry that I must leave out so many other significant contributions!

One of the principal instruments at Stromlo was the 74-inch (188-cm) reflecting telescope. The 74-inch telescope was erected in 1953, and until the completion in 1974 of the 3.9m Anglo-Australian Telescope at Siding Spring, this was the largest telescope in the Southern Hemisphere. In 1982, it was used to discover the fossil star CD-38245: a star so old that it is made almost purely of gases left over from the big bang.

It also was home scopes such as the robotic 50-inch (127-cm). It was an excellent example of how an older telescope could be outfitted with new controls and instruments to perform innovative work. The MACHO project was conducted on the 50 inch.

Two historical scopes come to mind, the Oddie, and the Yale-Columbia telescope:

The Oddie, was a wonderful 9-inch Newtonian telescope. The Victorian MP, James Oddie, presented this telescope to the Commonwealth government for use in the proposed Commonwealth Observatory. It was installed on the site at "Mt Strom" (as Stromlo was originally known) in September 1911. Over the years the Oddie telescope has made valuable contributions to Southern Hemisphere astronomy; it did some of the first measurements of the brightness, color and spectral classification of southern stars.

The Yale-Columbia telescope, 26-inch Grubb long-focus refractor was erected at this site for the determination of parallaxes of southern stars (it was the largest refractor in the southern hemisphere when first installed.

Moreover, there were other scopes as well ... But alas, from what can be seen from the air at this time, most, if not all of those telescopes have been lost. At appears that heat from the burning of the nearby bush /trees was hot enough to melt many of the domes at the observatory.

The Canberra Astronomical Society used the Stromlo lecture hall for their monthly meetings. During public nights, the public had access to a domed C14 scope, the Oddie, and a number of scopes brought to the site by members ... all through the hard work and generous efforts of the Canberra Astronomical Society.

I had the privilege of observing at Mt Stromlo several times and spoke at one of the CAS meetings. I still can recall flying down from the US to a CAS member's home to see SN1987, . I was there only 36 hours after the naked eye supernova was first observed. I still recall seeing the single star, at a distance of over 168,000 light-years, change in color and rightness over the course of an evening. I was one of the most important astronomical events I have had the honor to witness. I recall that every scope up at Mt Stromlo was all pointed at the Large Magellanic Could where SN 1987A was blazing away. The previous observing board schedule was cancelled as people raced to collect as much early critical data as they could in the early hours of the event.

I had the privilege of being with the members of the Canberra Astronomical Society on two of my several total solar eclipses: 1991 in Hawaii, US and most recently the 2001 eclipse in Ceduna, AU.

(Both trips count among my several successful viewings of solar totality. Although the 1991 Hawaii was a close call that was saved because my friend (the one who introduced me to the CAS) broke his arm a very short time before the Eclipse ... which allowed both of us to have a full view of Totality in Hawaii ... but that is another story!)

My best wishes and heart felt sorrow go out to all of those people who worked so hard to make Mt. Stromlo such a wonderful place for the public to visit and who helped the observatory make many important contributions to Astronomy. Much of what was lost cannot be replaced. Still it is my hope that those who are left will be able to rebuild something anew out this tragedy.

Check out Kit Peak Observatory and Arcosanti.

I've seen the stamement that there're more positions in chess than atoms in the universe many times. It's false.

Some estimates of number of atoms in the (visible) universe courtesy of Google:

• 4e78 - 6e79
• 1e78 - 1e81
• 3e78

• An upper bound of the number of chess positions: assume each square can have 15 states (white pawn, black pawn, white rook, black rook, ..., empty). Number of board states: 15^64, or about 1.96e71.

  The vast majority of those states are invalid. I've seen estimates of as little as 1e40 valid boards.

NGC 4013 was also the subject of the Hubble Heritage image for March 2001. Here's a ground-based image from the WIYN telescope at Kitt Peak. It's supposed to be visible in a 6-inch telescope. Next clear night I'll take a look.

Adaptive/Active optics can work in two ways. One way is to use a bright (and it has to be damn bright) star near the target that one's hoping to look at. Then, by seeing how the atmosphere distorts this (supposedly point-source) star, we can adjust the mirror to compensate. There are different ways to do this that involve just moving the image around or re-shaping the mirror altogether, but I won't go into that here. The trouble with this plan is that it's hard to find a star bright enough in the part of the sky that you happen to be observing. It has to be damn bright, since you have to read out the CCD several times a second in order to compensate for the atmosphere fast enough. The second method uses a sodium-type laser that excites a layer in the atmosphere very high up (i.e. above most of the clouds/water vapor/crap). This behaves as a sort of artificial bright star that one can have anywhere in the sky.

The Center for Adaptive Optics (at UCSC) has a decent simple explanation here.

All of this aside, this will probably NOT render HST obsolete any time soon, since this is rediculously hard to do and has yet to really be done convincingly in any large-scale way, as people at my institution are finding out.

M74 is 30 million light years away so this supernova went off 30 million years ago. This is about 15 times farther away than the Andromeda galaxy, which is the closest "true" galaxy to the Milky Way.

No criticism intended, but if you are wondering if something visible in a distant galaxy occurred days, weeks or months ago, you need to get a fast update on just how BIG the universe is. I recommend a quick trip to the Powers of Ten website....

However here are the puppies you really want. Spectacular as a desktop.

Actually, I think ESO's is a clear winner.
Compare ESO's version (largest is 4.6MB JPEG @ 1951x2366)
and
any on Hubble's page (wide @ 800x813, closeup @ 1000x800).

NOAO has better images than Hubble's too, but they're also wide angle (but still really nice)...
Hubble's MPEG movie animation is very cool though.

The first thing you should get hold of Xephem - a pretty good starmap/night sky program useful for locating things you want to observe. Once you have that, you should get some heavy duty image software, such as IRAF which I used extensively during my PhD. Take time to read the documentation available and absorb the methods used for analysing optical images - plenty of papers reveal in detail the methods used to identify objects and classify them according to morphology, colour profile or similar.

There are other sky plate analysis packages out there. Look for SExtractor (Source extractor) which some people prefer and which may make a better job of analysing nearby galaxies.

Also look out for tools in the links off a lot of these academic pages - there are lots of tricks available to flat-field images properly and get good catalogues built. If you are used to driving things from the command line you'll feel right at home. If you are used to GUIs with everything the learning curve will be steeper... But read papers on analysing optical CCD images - the http://xxx.lanl.gov/ preprint server gives you searchable access to lots of astro-ph preprints.

Cheers,

Toby Haynes

A very readable article, but I was surprised to see no other information on the referenced large telescopes. To save others from searching as I did, take a look at:

• VLT (Very Large Telescope)
  
• OWL (OverWhelmingly Large telescope)
  
• CELT (California Extremely Large Telescope)
  
• GSMT (Giant Segmented Mirror Telescope)