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Bla bla bla... You really don't know when to quit, do you?

When I said "make up stuff" I was obviously talking about vaguely defining some model that is not backed up by observation whatsoever. When you say that "we cannot simply deduce the behaviors of plasmas", then you're basically admitting that you can't model them, so you don't even have an hypothesis to test.

I keep repeating: if you want to take on mainstream cosmology, then create a consistent and testable hypothesis, and publish it. Blabbering about it on Slashdot to a single person is not going to help. Even assuming I work in the field, nothing you said has convinced me, quite the contrary.

The simple truth is, our Lambda-CDM computer models produce results that are strikingly similar to the actual universe.
Your models are basically, hey it's electric plasma with a bunch of new physics, but we don't know how it works yet, so we can't simulate it. And then you are surprised that the former is mainstream and the latter is fringe.

You are not even wrong. I feel like I'm getting dumber just by reading your posts. That's the last I'm going to say about it. I have better things to do with my life.

And the support for Big Bang style cosmic inflation (universe ballooning up from nothing in a trillionth of second) is sparse. (As opposed to the normal expanding universe we see that even old Steady State theory said existed.)

If cosmic inflation happened, everything real far away should be in its infancy, but we see sprial galaxies 13 billion years away.

Quasars are supposed to only be in the beginning of the universe in early times according to the Big Bang, and there are 2 of them within 800 million miles of us which should not even be possible. http://www.sdss.org/news/relea...

So we have old structures very far away well-developed with plenty of metal, which shouldn't happen.

We have "newer" structures nearby, which shouldn't happen.

Add to the fact there are no metal-free stars (Pop III) ever seen, it is difficult to see what aspect of Big Bang Theory holds true. Astronomy might be better off if it were discarded because a number of the popular conclusions double-down on bad science and result in wild goose chases (dark energy only need exist to support the Big Bang because only the Big Bang says expansion must be accelerating.)

• Immediately: take an introductory astronomy course at a local community college or continuing education program at your local university to demonstrate your interest,
• Then: assess your IT skills, and apply them directly to the support of an upcoming large ground- or space-based observatory. This is an especially sensible route if you do any database related work. The future of astronomy is big data and massive virtual observatories which collect together and make useful petabytes of information from a wide variety of facilities.
• Check the job listings at the American Astronomical Society, looking in particular for IT support positions where your domain knowledge would outrank that of PhD-trained astronomers (who learn to program "on the job" and rarely master grittier back-end systems). Realize that almost all existing and (especially) new astronomical facilities have substantial IT/engineering staff, and that your skills do not exist among traditional PhD scientists. Example: the LSST will produce 30 TB of data per night, which needs to be processed in semi-real time. Example #2: the incredibly successful Sloan Digital Sky Survey partnered with Microsoft database engineers to build its (at the time) state-of-the-art public-facing data archive. The late Jim Gray was instrumental in building the Sloan backend, and said his favorite thing about astronomical data is that it was "worthless" (by which he meant the usual access control layers were not necessary, freeing him to focus on much more rewarding and useful tools).
• Relocate to a mission control or operations center for the facility. These are often located at major research universities, or equivalent national facilities like the Space Telescope Science Institute in Baltimore, the National Radio Observatory in Charlottesville, VA, the Gemini Observatories (Hawaii/Tucson/Chile), etc. Advantage? You will very likely be immediately mixed in with groups of professional astronomers. You will be strongly encouraged to learn to speak their language, and to become more involved in the scientific aspects of the project. You will learn a great deal just through osmosis. You will likely be able to attend seminars, sit in on classes, bend the ear of willing faculty, etc. And the most significant advantage? You could be contributing directly to the forefront of astrophysics research within 3-5 years. Disadvantages: the pay might be somewhat less than similar background applied in the financial or health industries. Often the intellectual rewards bring talented engineers anyway. Also, may projects are time limited, so you positions are typically not permanent (but new projects are coming online all the time).

The data volume issue is brought up occasionally, but is a red herring. The SDSS dataset is comparable in size to that of Fermilab and CERN and is available to the public (hundreds of TB). No one said anyone should publish raw data either. A processed, manageable form is preferable. If the datasets are that large, then we should be working on publicly-funded data warehouses, just as we once built libraries across the country.

Astronomy has a history of sharing data, unlike particle physics. Furthermore, the NSF has data sharing requirements, and the NSF funds most astronomy activities in the US. The DOE funds particle physics (mostly). Data is also not available "on request" at all from particle physics experiments. There are some efforts to change this, but at the tail end of an experiment there is generally not a lot of manpower, money, or motivation to make data public. It's a big effort, really, and the culture of particle physics results in jealously guarded data.

So the best situation is that grant agencies require data sharing as a contingency for all publicly funded activities. (As the NSF has done) And I think we should put effort into data warehousing for publicly funded projects. Hell, give us DNA sequences, drug studies, pesticide tests, EPA water quality, everything publicly funded. Generally everyone wants a subset of the data. Giving anyone that asks the entire dataset is like sending them the library of congress because they want to read one book...

I'm sure the folks over at SDSS (Sloan Digital Sky Survey) would be happy to make use of a sensor like this.

I hope you're wrong too :-)

Oh wait... the source material from the SDSS (Sloan Digital Sky Survey) runs the hardware with the help of... drum roll... Linux (ref page 24)

BAM!

This MS product does indeed sound very similar to Google Sky.

I think the difference between both of these and e.g. Stellarium/Celestia is the database that sits behind them. Usually "planetarium" software consists of a bunch of points for stars, with perhaps a few objects represented by pixels. You can upload images but you have to do it yourself.

In contrast, Google Sky (and presumably the MS telescope) show you pixels from large databases such as the Sloan Digital Sky Survey. The latter covers roughly 1/4 of the whole sky.

Google is heavily involved with the LSST project.
MS has been involved in the Sloan Digital Sky Survey for quite some time via the late Jim Gray.
Its great for astronomy that both of these companies are competing in an area with little prospects for "monetization".

More than just simulations -- if you look at the SDSS data, you can clearly see the filaments. Mitaka is a good way to see a summary of the data on a PC; Switch to launch mode, and then zoom all the way out. You'll see the filament form as you get closer to the present (the center,) and see things more homogeneous at the edges (in the past.)

there is no workable cosmology being presented

Indeed, there is no alternative, scientific cosmology being presented.

When you get a chance, would you mind providing links to material on any such alternative that addresses (quantitatively, of course) the following:
* why the night sky is dark
* the Hubble relationship (i.e. the relationship between observed redshift and distance, for galaxies, quasars, GRBs, etc)
* the primordial abundance of light nuclides (H, D, 3He, 4He, and 6Li)
* the SED (spectral energy distribution) of the cosmic microwave background (CMB) - i.e. its 2.73K blackbody spectrum
* the CMB dipole
* the CMB angular power spectrum
* the observed large-scale structure of the universe (here's an example: http://www.sdss.org/news/releases/20031028.powerspectrum.html).

You act as if there is only one possible cosmology that can possibly be created

No need to read the APODNereid tea leaves ... I'll say it directly, loudly, and clearly: I think the number of possible cosmologies (to use pln2bz's term) is certainly greater than one. Further, only a few decades ago at least two possible cosmologies seemed consistent with the relevant astronomical observations and experimental results (today there's only one, that I know of).

many very intelligent people have backed the plasma-based cosmology approach

I thought you'd've given up using this kind of argument; you've certainly been beaten up for it many times, here in SD.

Once upon a time, many very intelligent people backed the "Earth is flat" idea too, and the élan vital approach. The universe cares not one jot what people, intelligent or not, back.

I can tell that you have not read the materials because you consistently assume that the arguments are less powerful than they actually are.

Right, like the one about magnetic reconnection has never been observed in a laboratory (URL:http://science.slashdot.org/comments.pl?sid=426528&no_d2=1&cid=22144874>), or the solar wind continues to accelerate even as it passes the planets! (http://science.slashdot.org/comments.pl?sid=426528&no_d2=1&cid=22148864), or Arguing that space must be charge neutral on some scale is tantamount to declaring that we've reached a conclusion on a metaphysical question (http://science.slashdot.org/comments.pl?sid=358211&cid=21392029).

your objections to it would give way to more nuanced feeling towards it

If you care to read my previous SD comment, in this thread, you'll see what I'm planning to do. In a nutshell, I will examine - using standard methods found in science - "the plasma-based cosmology approach"; specifically, the extent to which it is internally consistent, independently verifiable (or can be independently validated, if you prefer), and key characteristics of the methods used to classify things as "facts" (and "evidence"). I intend to use an empirical approach.

the telescopes are getting better

Indeed they are!

Let's do a little "what if" experiment, shall we?

Imagine you were granted 1 million seconds of time on the Hubble Space Telescope, using any instruments (or combination), and spread out over as much as a year. What would you use your time to observe?

Imagine the same, on any (or combo) of the VLTs (http://www.eso.org/public/astronomy/teles-instr/whitebook/).

On Spitzer (http://ssc.spitzer.caltech.edu/), XMM-Newton (http://xmm.vilspa.esa.es/), any of the ATNF (

I don't think so; My understanding is that it's the force of gravity.

Here is the picture I have heard:

The universe basically, from any point, stretches out in all directions. Gravity pulls a given lump in all directions at a given time. But local things are more powerful by the law of gravity, than far things. So things start lumping with their neighbors.

Some lumpings occur earlier than other lumpings, which cause then to exert a stronger pull. These become the super-clusters (joining points between filament; such as the Virgo Cluster.)

So masses are basically pulled towards the closest super-cluster. But, ah-hah, some are pulled strongly by *two* super-clusters. These become the filament ("bubble walls.")

If you download Mitaka, you can see a lot of these things first hand, with data directly from the Sloan Digital Sky Survey.

Anyone know what this is?
588298661962973323

This is one of the most beatiful pictures.
I am not an astronomer, but I think it is a huge colision of an eliptical galaxy sucking a huge eliptical one.
http://cas.sdss.org/astro/en/tools/chart/chart.asp ?ra=156.44275121&dec=13.71685856

Here !

I find myself thinking "Are these the arms of a spiral?", then I close one eye, squint the other, stand on my head and rub my tummy for 2 minutes, then I click "Star/Don't know".

They should a "Fuzz" button. Sometimes, that helps.

The most interesting object I've seen so far wasn't in the middle, so I wasn't asked about it but... Any astronomer in the audience can tell me what the object to the North-East of center is in http://cas.sdss.org/astro/en/tools/explore/obj.asp ?id=588017677691715886? Can I name it the "Mammaire galaxy"? :)

Yup. There was a paper a few years back entitled "terascale sneakernet", by jim gray and a couple of guys at MSFT research division on this. You can find it in the arxiv.

This concept has also been applied to such things as the Sloan Digital Sky Survey. Astronomers do tend to generate a lot of data with large surveys such as this.

Lots more than that --- just a quick search of The Sloan Digital Sky Survey yields over 15,000. Probably even a lot more than that are known.

FWIW, I have had very good experiences running postgres in astronomy applications, including for of order millions of galaxies with of order hundreds of attributes in the Sloan Digital Sky Survey. For scientific applications, open-source is a must, because (a) you have to be sure that the db is doing what you think it is, (b) you have to be able to rely on support or self-maintainance into the asymptotic future, and (c) (usually) you end up having to make small customizations.

Point (b) is especially big: in the Sloan Survey early days we had a proprietary database with our only copy of some of our data; when the company went belly-up (I think is was Objectivity), our data was effectively "encrypted" in whatever proprietary internal format was used by Objectivity and we had no way to reverse-engineer it, and no-one to call.

On point (c), try calling Oracle or Microsoft and asking for customizations that astronomers want. Evidently they don't consider us an important part of their market!?

The Sloan Digital Sky Survey. 8,216 square degrees imaged and over 6 terabytes of data collected to date, and counting.

Depending on what you consider a "single picture," I think SDSS (see http://sdss.org/) has them beat. SDSS scans aren't generally stored in a single file, but they are taken in a single exposure (sort of; see http://www.sdss.org/dr3/instruments for more information on drift scanning), and have vastly more pixels than the one presented in the article. The pixels are stored in many files for convenience, but I think it unreasonable to claim that a stripe is not a single picture, but that a single file constructed by stitching together many files is.

If having all the pixels stitched together, but not in a single file, is enough for it to be considered a single image, an argument can be made that the entire survey is a single picture!

-Hil

Depending on what you consider a "single picture," I think SDSS (see http://sdss.org/) has them beat. SDSS scans aren't generally stored in a single file, but they are taken in a single exposure (sort of; see http://www.sdss.org/dr3/instruments for more information on drift scanning), and have vastly more pixels than the one presented in the article. The pixels are stored in many files for convenience, but I think it unreasonable to claim that a stripe is not a single picture, but that a single file constructed by stitching together many files is.

If having all the pixels stitched together, but not in a single file, is enough for it to be considered a single image, an argument can be made that the entire survey is a single picture!

-Hil

I don't think you understand what a survey is.

In fact, the Sloan Digital Sky Survey (in which Fermilab also plays a major role) transfers its imaging data from the the observatory to Fermilab (where it is reduced) by FedExing DLT tapes. I do not know what it planned for the DEC.

You asked a very good question, and it is one that every astronomer gets confronted with at one time or another. I'll give you a quote I borrowed first, and then my opinion second. From a report by the National Science Foundation, here is a good summary of why astronomy is important in general:

The essential purpose of fundamental scientific cutting-edge research is to advance knowledge. Regardless of whether information of potential relevance to particular applications is sought at the time the research is initiated, the insights produced by the research enlarge the knowledge base on which future scientific and technological advances can draw. For example, studies of quantum mechanics in the 1920s were considered to be "pure esoterica" by many at the time--few people understood the theory. However, in the succeeding fifty years, results of this work in combination with findings and applications from other fields produced transistors, lasers, and electronic devices used today in a wide array of activities, including information processing, communications, and video imagery.

Here is my opinion, second: Astronomy research does not produce tangible results that improve your day to day life. I can point to technology spinoffs (X-ray machines at airports, CCD imaging - i.e., digital cameras) that you can attribute to astronomy, or you can argue came more directly from somewhere else (military). I could point to the fact that astronomy as an "industry" drives IT development (our storage needs are growing exponentially - check out the Sloan Digital Sky Survey and look up their daily data flow). However, what I would say is that what drives almost everyone in astronomy to do what we do is our strong desire to understand the universe AND communicate that to Homer, Marge, Bart, Lisa, and Maggie. The fact is that astronomy consistently rates as the #1 or #2 science most interesting to the public (the other is paleontology). We all have a desire to understand the universe, and I have personally been thanked many times by people for explaining how our Solar System works, where we are in the Milky Way Galaxy, and how we know the Universe is expanding. It is up to the tax paying public to decide if that is worth funding (BTW, our funding is a tiny fraction of the national budget compared to cancer research, and rightfully so!).

I really don't have an axe to grind about this. If Hubble is cancelled, my job won't be affected. However, my motivation for posting on this topic frequently is to try and combat a few misconceptions, and the previous poster struck a nerve. The fact is that the tax paying public has invested billions of dollars in Hubble, and it has paid the public back by being one of the most (if not the most) productive telescopes ever built. Please check out HubbleSite and page through the immense archive of fabulous imagery (I recommend looking for the V838 Mon light echo image, the Antennae Galaxies, Stephan's Quintet and/or Seyfert's Sextet, and any of the Solar System images). I do not dispute that we should have a dialogue about the future of Hubble. We should weigh the risks of servicing it to keep it in service for another decade. My position is that if the Shuttle (or a replacement) flies, servicing Hubble is a worthwhile mission because it simply can't be replaced by ground-based telescopes, and there is no space-based telescope that will have the capability of Hubble that will fly within the next 10 years.

World's Best Telescope (including those that orbit it) You can even see stars in the southern hemisphere without going there. Doh!

Oh, and not only is diving, expensive, difficult, relatively less than safe. It's also slow. It wastes a lot of time and resources. One of the reasons we know so little, is because of how long it takes to get there. Jennycam for hydrothermal vents or the grey goo wastelands would likely reveal much.

I've been working in the Grid Computing area for the last two and a half years, and would like to make a stand for all of us who aren't just worried about bigger supercomputers.

Supercomputers are great, but the number of big computing problems that can handle being run on distributed groups of supercomputers is small. That's why things such as the Earth Simulator and the ASCI programme still exist - sometimes it's just better to build a bigger box!

Where Grid Computing might take off in the science and business mainstream is collaboration and sharing of resources. In particular, I work on producing middleware to try and share and unify data resources. In the astronomy community for instance, they have spent many years standardising the naming schemes for their databases and as a result, projects such as Skyserver and SkyQuery are becoming possible. Now consider the bioinformatics field: hundreds of competing standards for naming things as simple as gene expression ids. Grid computing should provide some of the tools to make knowledge extraction from the many disparate scientific databases possible.

This has applications in business, and it's something we're already seeing in the uptake of Web Services. One recent Grid Computing initiative - Grid Services - is pushing the boundaries of Web Services, and extending them to standardise functionality such as state and lifetime management which should make them more useful for the kinds of collaborative problems which are cropping up in both business and science.

For instance: a car manufacturer has an agreement with different suppliers of airbags - obviously information exchange must take place to ensure safety of the passengers, but both the car manufacturer and airbag supplier will not necessarily want the other to be able to see all data for their parts, just use it. As suppliers change, the manufacturer must ensure that data is properly traced and expired. This is not much different from scientific collaborations, financial collaborations or even network gaming where we have a huge number of swiftly changing, transient resources.

It is these problems of dynamic collaboration and maintenance of resources that Grid Computing may eventually solve.

-T

This looks really interesting and I'm looking forward to playing around with it. I was wondering how it compares with other similar-sounding astronomical survey projects that combine existing data such as the Sloan Digital Sky Survey. Is it expected to replace the existing ones?

Take a look at SkyServer for an "inverse TerraServer". It was co-developed by Jim Gray of Microsoft Research, one of the developers of the inverse TerraServer. In fact, that is how he describes the new project :-)

... or perhaps that should read, amounts of astronomical data. The Sloan Digital Sky Survey participants often need to be able to replicate their database of astronomical objects. This is about a terabyte of data. One of their collaborators has a (ugh, Microsoft Word document) on why Tera-Scale Sneaker Net is the cheapest and fastest way to do it.

Alex and his team design and build databases used for distributing results to astronomers and the general public. See the SDSS skyserver to see what they have done.

• SDSS image gallery
  
• SDSS Project Book
• Astro's webpage

'A really creative way to add "depth" to the image'

Well, this superlative piqued my interest. Unfortunately I then read the linked article (yes I do realize that isn't the done thing). The "really creative" way?

Red shift

I don't mean to undermine the goals of the project, which are clearly noble. But the top level comment is rather tabloidy.

I do have a serious question. What kind of accuracy do you get from this data? I understand latitude and longitude (or psi and phi) can be given to a tiny fraction of an arcsecond, but how about distance from earth? +-10%?

A flame may be fleeting but obscurity is forever.

Well, ok, camera resolution might not be so important in most research, but I would imagine that doing the Palomar sky survey (hundreds of huge plates) with CCDs would be impossible (it would probably require trillions of pictures).

The Sloan Digital Sky Survey is using CCDs to map one quarter of the entire sky, in five passbands. Its main camera uses a mosaic of 30 2048x2048 CCDs to cover an area about 2.5 degrees across (although there are gaps between the chips). Other mosaic cameras have even more pixels.

Future ground-based surveys will use electronic detectors, not photographic plates. The increased sensitivity and linearity of electronic detectors, plus their inherent digital output, make them far superior to plates.

One can extend this idea to geological surveys, amongst others.

That's not very different from how Napster operates. One querys a central server, and the peers who hold the actual data return the result.

So you see, there are many ways in which peer to peer is not about piracy at all!

[RANT] I become increasingly frustrated with the way science (especially astronomy) is portrayed on /. Although I'm happy that ppl take interest in this field, I feel that creating hypes or suggesting breakthroughs in every little article is just not the way to go. It may be the american way... I dunno. For NASA, pumped PR is essential for its survival. I'm also amazed that whereas /. readers are in general critical and sceptical, when the subjects changes to science they believe everything without actually trying to understand what is being said.[/RANT]

Finding clusters @ z = 0.3 is no big deal and wont challenge our current understanding of how quickly the Universe evolved into its current hierarchical structure of stars, galaxies and clusters. The current theoretical (numerical) view of the deep universe comes from the Virgo Consortium and predicts the existence of clusters on much higher redshifts. Wat is interesting is that it appears to be relatively easy to image large amounts of cluster. Clusters have been found out to a redshift of 1.2 (universe 40% of current age) and protoclusters at z = 2.2 (universe 25% of current age). CAVEAT: this MACS sample are selected on basis of their X-RAY properties; they were snatched from the ROSAT source list. Only heavy clusters with lots of infalling gas will produce much X-RAY emission, therefore biasing against smaller/less gass rich clusters. It is completely unclear if the study of high density regions (ie clusters) is representative of global picture galaxy and cluster evolution.

There is also a program underway called the Sloan Digital Sky Survey; a huge project where they (amongst other things) try to find clusters by optical selection in an automated way.

Finally, the article states "The analysis is not yet complete, but it is already clear that our observations are in conflict with a high value of omega."

Translation: this does not mean that our current picture is challenged. To the contrary: this study very crudely confirms other analysis (spatial structure in cosmic microwave background) and arguments for low omega_matter. Low Omega_matter is the currently favoured model. Trying to present this study as a breakthrough in this respect is false.

Well, could this be made into an app like SETI@Home? A nice distributed app that runs on all sorts of computers with some pretty screensaver (maybe of the current pics being processed) might be something people really like. Even just a catalogue would be pretty extensive. But if a whole lot of people each proccess one picture, it might be worth it.

There are possibly some applications that could be automated, such as building a complete two-point correlation function for the clustering of the objects in the field, or maybe trying to categorize all the objects by colour, redshift and position into groupings in space and colour. However, most of these tasks are doable in a reasonable amount of computing time - say two-weeks computation on an UltraSparc machine (although the two-point correlation function is an O(n^2) problem, that requires 10^16 comparisons at a rough estimate, with maybe 10^8 comparisons a second, that would require ... umm ... err ... about 3 years of CPU time). So yes - possibly an automated tool might well be worth it. I strongly suspect that few astronomers would bother to do the correlation function for the whole field at all scales, and would settle for looking at the function for scales up to around 4 degrees separation on the sky (that's much bigger than the largest known cluster of galaxies).

However, looking at the automatically processed picture strips, I see all sorts of problems with background level correction (the background appears to be wavey in these pictures so there is definitely room for improvement). Modern astronomical analysis often requires significant time spent on looking at a particular frame of interest - I spent over a year examining and refining an image of a pair of Quasars as part of my thesis - so my feeling is that there is much to be gained by picking an object which interests you, possibly from a Radio or X-ray survey, and following it up with the SDSS survey here. With this much data I think you can be assured that the Astronomy community will get to grips with the important statistical analysis on it's own. What it won't be able to do is follow up every field, every interesting quasar or galaxy and really really work on it. It may be possible to see gravitational lensing (although it won't be very clear since the point spread function will be around an arcsec) or do some funky image processing to try and deconvolve the images to recover more detail. In fact, there are lots of things to play with which are unlikely to ever get done on every part of this image data, so grab yourself a copy of IRAF or Source Extractor and go play.

Cheers,

Toby Haynes

Of course, tcl is also used. Most of the Sloan Digital Sky Survey software is written in Dervish, which is a Fermilab branch of tcl.