I've noticed that some of the Advance Reader Copies of Spider Star are creeping out into the world either via comments on the internet, or for sale on ebay

I came across this cool site about crayon physics. Really neat. Probably not new to some of you reading.

And finally, we'll have a site redesign very soon. It should be more pleasing, easy to read, and comment friendly. Also will have a live journal mirror.

The easy answer is that when you're just poking around, you might discover something important. A number of very important discoveries have been made that could not have easily been anticipated. Plastics and penicillin are two major serendipitous discoveries.

My field, astronomy, is about as basic as it gets, with little likelihood of practical results. The most obvious practical result is the discovery of a near-Earth asteroid a long time before an impact. Less obvious practical results are things like algorithms to detect sources in an image that also apply to things like detecting tumors.

But even aside from these practical applications, astronomy, and other basic research is worth funding.

One of the things that makes human civilization great, in my opinion, is that we care about knowledge for its own sake. Existence isn't only about food, shelter, and mating. There is an inherent value in determining the nature of the universe and our place in it.

I mean, how do you put a cost on determining the age of the universe? On the discovery of gravitational lensing? On determining the origin of gamma ray bursts?

We're not just hear to make life easy, to make a profit, to advance a particular ideology. There's value in basic research leading to fundamental truths. We're not spending the house on such endeavors. We're spending a steady small fraction of our money on these things. Certainly less money than we spend entertaining ourselves with frivolous diversions (which I too enjoy, very very much).

The same case can be made for art, humor, anything that we like to do that isn't for immediate gain. Humans are thinking animals, and that thinking thing really should get us somewhere. We can figure things out. Some of those things will be useful, some won't, but they're all worth knowing.

I'm amazed at some of the things we've been able to figure out. It's cool to be a scientist now.

In the 1990s, that trend hit cosmology with "dark energy." Perhaps I'm being a little unfair, since there was a precedent set already with dark matter, but I'm jumping ahead already. Let's take a few steps back to look at the history of dark energy and what it means in a cosmological context.

The dynamics of the universe, how it expands, contracts, or doesn't, is governed by Einstein's theory of general relativity, and more specifically by something called the Friedmann equation. This equation is basically just a fancy statement of energy conservation and is the equivalent to the more mundane case of tossing a ball in the air. If you give it a lot of energy, it zooms off into space. (OK, not you in this case, but Superman.) If you don't, it slows down, stops, and falls back to Earth like the Hulk taking a big but not infinitely super leap (jumping to infinity and beyond would have made that comic/movie pretty damn short).

So what determines the energy and the effective gravity pulling things back together? Well, it comes from a combination of the equivalent energy density of things (e.g., matter and radiation) and their pressure. Matter and energy we under stand, but general relativity allows for other components: a constant term called the "cosmological constant" and a complicating curvature term, since spatial geometry need not be flat necessarily. Sorry if this is getting complicated, but it is, intrinsically, a little bit.

The so-called cosmological constant term expresses in some poorly understood manner the energy density of space, and can act as extra gravity or as a type of anti-gravity. It has negative pressure, that is, it exerts a tension through space, and Einstein called it his "greatest blunder."

He believed that the universe was static, eternal, and he solved the Friedmann equation with a special value of the cosmological constant that perfectly balanced gravity. This was a decade before Hubble and others discovered the expansion of the universe, which Einstein might have predicted if not for his bias. Einstein's static universe also suffers from being unstable, since the cosmological constant would be smooth over all space while the effects of matter are concentrated, and locally the balance could never be perfect and the universe would not remain static forever.

With the expansion of the universe confirmed and no other evidence in support of a cosmological constant, the idea was set aside as unnecessary. Alan Sandage, Hubble's successor, and others, proposed various tests to look for the deceleration of the universe. Even if the Hulk jumped off into deep space, Earth's gravity should slow him down, a little, over cosmic time.

All it would take, in Sandage's estimation, was to measure the distances to objects some five billion plus light years away with an accuracy of better than ten percent. Well, it turns out that this is really hard to do. The technique usually employed is that of the so-called "standard candle." You take objects of known brightness and see how bright they look at such extreme distances. In a decelerating universe, at a given distance they should look a little brighter than you might expect based on a steady expansion rate. Maybe Superman, or Reed Richards with technology unknown in the real world, could see individual objects that far away. For the most part, even with the Keck telescope, we can't. Best we can do is entire galaxies, quasars, supernovas, and gamma ray bursts.

It wasn't until the 1990s that we learned to determine the intrinsic brightness of any of these well enough to conduct Sandage's test.

There were a couple of competing supernova groups then working on the dual problems of the calibration of supernova luminosity and the detection of supernovas at such extreme distances. A young post-doc in California, Adam Reiss, was the first to put together the data with the appropriate calculations and to measure the deceleration. Except it wasn't there.

The distant supernovas were fainter than expected.

The universe appeared to be accelerating.

In some sense, Reiss was just a person at the right place at the right time to conduct the test and gain fame and fortune for this unexpected discovery (and he has won some big money prizes, been featured in TIME magazine and other places). But in another sense, he has been the right person. Correctly assuming that the community would be skeptical, he performed a tour de force trouble shooting all the possible objections to his conclusions, and they have held up over the last decade. He's followed up the work and extended the results, and they continue to look real.

So, what's up with this acceleration? For one thing, it hasn't surprised everyone. The amount of the acceleration implies an energy density that, together with the known matter, makes the universe "flat." That is, it obeys Euclidean geometry on large scales. Theorists like Stephen Hawking (and Dr. Stephen Strange, perhaps?) already believed the universe to be flat on other grounds, and with the observers claiming insufficient matter, something like this energy density associated with, well, nothing, fit the bill. Like dark matter, exerting its effects without being seen, this component was dubbed "dark energy."

And mathematically, the dark energy can be described exactly by the cosmological constant. Even so, we don't know what it is physically, if that interpretation is correct. It could be vacuum energy, associated with virtual particles appearing and disappearing in such short periods of time that they can't be seen. Our current understanding of vacuum energy, however, suggests that this explanation is something like 150 orders of magnitude off. That's pretty wrong for astronomers or the Tick. Even the Dark Tick.

Particle physicists have suggested another component of the universe, something called "quintessence," that could also explain the acceleration. Quintessence would have similar but not identical effects as the cosmological constant. Current experiments are designed to distinguish between these two possibilities. NASA has recently approved an Einstein Probe, the Joint Dark Energy Mission (JDEM) that will focus on investigating dark energy.

Why is it important to figure out what is powering the acceleration? Beyond just knowing the answer, the ultimate fate of the universe depends on the question in a bigger way than even Dark Phoenix could affect.

If the cosmological constant, some form of vacuum energy, is responsible, someday the acceleration will become so large that even nearby galaxies will be moving away from the Milky Way at greater than lightspeed. The extragalactic universe will go dark as we experience the "Great Empty."

If Quintessence is the dark energy, the results will be more extreme. The accelerative anti-gravity force will become so strong that even atoms themselves will be torn apart in a "Great Rip."

Cool, huh? Well, Dr. Fate might think so.

I remember reading a Jim Starlin WARLOCK comic book in the late 1970s. Adam Warlock had flown into deep space and when he returned to Earth, he was many astronomical units across. Starlin, brilliant writer and artist but confused layperson, suggested that even within the galaxy different regions expanded at radically different rates. Even though it was amazingly wrong, the notion was mind-blowing and cool and inspired me to look into cosmology more seriously.

Today, as a hard science fiction writer, I'd never let myself make an error like Starlin's, but the possibilities are as mind-blowing. The dark astronomers like Adam Reiss will continue to let us know what they are.

SPACE.com -- SETI: Is It Worth It?

This article mirrors my thoughts on basic research and a lot of the points made apply not to just SETI, but to astronomy in general. It behooves us as a curious and thoughtful people to take some time and effort to look around us and see what's out there. For any species this should be as natural as breathing.

What does it take to become a professional scientist? To get into graduate school, persevere, collect a PhD and land a job in the field?

A lot of things, but not all obvious to the uninitiated.

I used to like to tell people that it took three qualities, two of which might not be obvious. I now think it takes five.

First, it takes brain power. Intelligence. Talent. The ability to do the hard work.

This is probably obvious to most, but is sometimes ignored when people want to put down a scientist reporting results they don't like. Every scientist has some native intelligence above and beyond that of the general population. Perhaps not a lot more, but above average. Scientists get not only through college, but into graduate school and through it. Few graduate programs let in students with GPAs below 3.0, which is pretty good at colleges other than Princeton or Harvard.

Now, I will admit that there are plenty of gradations of intelligence above average, and that there are some stupid smart people and some smart stupid people, but that's the subject of another, future post. PhD-level scientists are all smart, but plenty fall way short of genius level and fail to apply their brains to every problem before them.

OK, second: stick-to-itivness. You don't get a PhD for pointing out small things. You have to show that you can produce a significant step in our understanding of the universe, and that requires many months to years of sustained effort to complete. Usually at least three years. If you can't start, sustain, and finish a project that takes longer than a year, forget about being a scientist. There are plenty of smart people, including geniuses, who can't be scientists because they're flighty, lazy dilettantes. We all know them, and most of them make me shake my head. I've had a couple of promising, smart students who will never make it for this weakness. They make good points, have good criticisms, but never produce anything of their own all that worthwhile.

Third item: communication skills. Maybe it's possible to be a scientist without good communication skills, but, oh, wow...how will the career suffer. Scientists must write papers, proposals, and give talks. Referee papers. Review proposals and papers. The ones who can't communicate clearly and effectively will not get their work considered seriously and will have poor careers, assuming they can even get through writing a thesis and defending it successfully. Staying in science without being able to secure funding is tough. Very tough.

That was my original list, but I finally decided that I had to add two other items.

Curiosity and attention to detail.

Curiosity is what drives any decent scientist. Having a PhD and securing a permanent position means having independence to pursue a line of research. That requires curiosity. Grad students who blow away the GRE but need to be told what to do every step do not make good scientists. They're technicians at best, which is fine, but a different career. Scientists are curious and need that to do research. There is a scientific method, but there's no algorithm to how to develop and test the next hypothesis. It does require that spark.

Finally, attention to detail. This was something I was never great about growing up and had to learn myself. It's amazing how many details must be addressed in bringing a research project to publication. Ideally every journal article describes every project in enough detail to duplicate it. That's a big responsibility, and anyone who can't be bothered to get those details right nearly all the time or better can't be a good scientist. Mistakes are always going to happen, but they shouldn't be too common. And sometimes in science, the results and their interpretation turn on those details as they do in few other fields.

Summarizing, every would-be scientist needs:

1. Raw brain power
2. Dedication to finish long-term projects
3. Communication skills (writing, speaking)
4. Curiosity
5. Attention to detail

There's no crime in not becoming a scientist. Not every smart person has these qualities. And there are plenty of smart people who aren't geniuses who make great scientists. As a professor mentoring students, I see some of the brightest fail on some of these points every year, and others less gifted succeed on their other strengths.

Another day I'll rant about the stupid smart people who are the bane of the system all too often...

This is an older article, not quite current, but still a valid description of the current thrust of research in my primary area of quasars. I'm getting caught up after Milehicon and Halloween stuff, and not doing a great job of it just yet. I hope that will change this weekend, with more science, science fiction, blogging, and more.

SPACE.com -- Obscure Comet Brightens Suddenly

Naked eye comets don't happen all that often (remember Hale-Bopp, or do we forget so quickly?). Holmes was a known comet, unlike Hale-Bopp, and brightened without warning. Probably a reaction to Bruce Willis approaching, no doubt.

In a more recent update, the comet is apparently developing a tail, as expected.

SPACE.com -- Scientists Say Dark Matter Doesn't Exist

OK, this one is about a forthcoming paper now available as a preprint. After results last year on the Bullet Cluster seemed to be a direct proof of the existence of dark matter, a couple of modified gravity theorists have gone through some contortions to argue that modified Newtonian gravity can still explain the results. I've printed the paper to take a look, but I'm skeptical. This is a case where dark matter offers an immediate and predictable explanation, but modified gravity must struggle after the fact. In my opinion, without a close read. I'm also suspicious of the submission/revision history. The paper was apparently submitted the first time to the preprint server before being refereed, a very bad practice, then resubmitted after acceptance, and resubmitted a third time after additional unspecified revisions. Funny that it's only now getting popular press, at least that I've seen.

Anyway, their basic idea is that if you take out the dark matter, and modify gravity to account for the lensing, you can somehow account for the separation in the center of the lensing mass and the center of the baryonic mass (dominated by the hot X-ray gas rather than the galaxies).

Some interesting commentary about this modified galaxy (MOG) theory and the bullet cluster results can be found here. My own bias as a simple-minded observer is that the MOG people are jumping through a lot of hoops with some extra parameters that might not be fair, while the very straightforward interpretation favors dark matter.

Some meatier posts to follow soon...

"The Right Brain vs Left Brain test ... do you see the dancer turning clockwise or anti-clockwise? If clockwise, then you use more of the right side of the brain and vice versa.

"Most of us would see the dancer turning anti-clockwise though you can try to focus and change the direction; see if you can do it."

It took me a minute, but I could make her spin both ways even though I was sure at first it was only one.

So today, it was a request to review proposals for the Hubble Space Telesope (AKA "HST" -- this is NASA associated, so expect more three letter acronyms, AKA "TLA"s).

I'm busy now, and will be busy in May when they hold the review, but I'm likely to say "yes." I said "no" last year, and I've said "yes" to HST once or twice over the years. I've reviewed for the National Science Foundation (NSF), for the Spitzer Space Telescope, for NASA's Infrared Telescope Facility, for the Chandra X-ray Observatory, and been asked to be on review panels for several other telescopes/programs.

When you first start getting these requests, it's flattering. You're a recognized expert in your field and your help is wanted at the national level. And the stakes are high, with the telescope time and analysis funds being awarded worth millions of dollars and sometimes even careers. The process is amazingly educational and worth doing for that reason alone. But boy, is it a lot of work!

A few weeks before a two-day face-to-face meeting (in Baltimore for HST), you get sent about 60 proposals. Each is about eight pages long, with most of those pages dedicated to the scientific justification. You have to read them carefully and critically to discuss with other world experts, and no one wants to look like an idiot. Furthermore, some astronomer, or group of astronomers more likely, has put their blood, sweat, and tears in each proposal, requesting some small portion of HST's time over the next year (AKA "cycle" since it usually doesn't match a calendar year). Out of those 60 proposals, about a dozen on average will make it through and be done by HST.

At the two-day meeting, about a dozen panels of about eight astronomers each discuss the strengths and weaknesses of their group of 60 proposals. Well, almost. There are preliminary grades submitted, and usually the bottom quarter is triaged and not even discussed. Experiments over the years have shown that essentially never does a proposal in the bottom of the preliminary rankings get time even after a more thorough discussion. It might seem unfair, but it's efficient and people are volunteering their time. The proposers do get informed about their low ranking and get comments from primary and secondary reviewers about the pros and cons of their proposal to help them revise it for resubmission later.

Each panel is specialized into a subfield of astronomy, like stars, galaxies, cosmology, etc., and the relative amount of time awarded to each subfield to distribute is goverened by the proposal pressure -- how many proposals there are in each subfield. Oh, and there are proposals to use archival data or conduct theoretical research in support of HST science, but these only ask for money, not telescope time. The proposals for telescope time also get money, analysis funds from NASA, to help ensure quality, timely analysis of data obtained.

The discussions sometimes become heated, and sometimes hinge on individual egos or individual biases (which is why there's a group making the decision). They tend to be fair, but sometimes a little arbitrary; a lot of high-quality projects don't get done. But essentially every approved program is very worthwhile, and the slate usually includes a range of big, solid projects to small, speculative projects that might have a big payoffs.

There are more details, and it's more complicated than this, but that's the gist of it. This year is especially crucial, assuming that Hubble is serviced by the Space Shuttle and its suite of crippled instruments replaced by new ones. The community has been waiting for years for this, and there's a lot of pent-up ideas about what to do waiting to turned into proposals. I have a few of my own (I've had several projects get through the process myself).

So who decideds where HST points?

The answer this year is me, along with another hundred astronomers or so, sifting through about a thousand proposals from around the world.

This is the beta test of the Scientific American community, which should be going gold next week as I understand it. I've posted my brief history of dark matter there, and will likely often double up by blogging the same entries here and there (automatically, I hope). But I might keep some things separate, too...I'll let you all know.

But check it out -- a lot of scientists and sf writers blogging over there!

OK, I'm going to have to do one of these now. I can get a lot stranger, and keep it real...