Every day, every night, all over my whole life through; Just let me be in the dark with you

Yesterday's NSF Astronomy and Astrophysics Post-doctoral Fellows symposium was inspiring, like they always are. It's amazing how a bunch of people talking about doing what they love will remind you that you are doing what you love, and how great a privilege it is. I'll try to write more about the life of a post-doc in the future, but for today, I'll go over some of the the bad (silly media coverage) and good (inspiration) that comes with being a scientist.

Bad media; no donut!

For those not familiar with it, Slashdot is one of the leading, if not the leading, techie sites out there. The website name can even be used as a verb: a small website is considered "slashdotted" when Slashdot throws so much traffic its way that it shuts down the server. As a general rule, Slashdot gathers up stories on all sorts of technical topics, posts a link to them with a quick abstract, and allows people to discuss them endlessly. Sadly enough, given that many people out there have a legitimate interest in science, the quality of the posts is often extremely poor. The two most recent ones are cases in point.

How a Pulsar Gets Its Spin: Until now, the assumption has been that the rapid spin of a pulsar comes from the spin of the original star. The problem was that this only explained the fastest observed pulsars. Now, researchers at Oak Ridge have shown that the spin of a pulsar is determined by the shock wave created when the star's massive iron core collapses.

Rule number one for any journalist or media-related site: never quote a press release; it is an advertisement and you are likely being played a bit by them. In this case, the researchers from Oak Ridge, one of whom I've met and both of whom I respect, haven't "shown" that anything is conclusively "determined" by anything else. They've suggested something, and provided numerical evidence, but that is nowhere near as conclusive as the press release would indicate. Like most active research fields, this is still an open question. Science is not a progression of certainties, it is a series of hypotheses with supporting evidence where eventually the claims become strong enough that they can be considered essentially settled, barring future evidence to the contrary. From the paper itself:

This provides a new mechanism for the generation of neutron star spin and weakens, if not breaks, the assumed correlation between the rotational periods of supernova progenitor cores and pulsar spin.

Note the language here: "provides a new mechanism". This is science, in its suggestive glory. Nothing is certain yet, but they think they are on to something. The press release is a media staple, but it is vastly different than science; try to remember that the next time you read another breathless story...like this next one:

Black Hole Found Inside Globular Cluster: Contrary to the prediction of some computer models, scientists have found a black hole resting peacefully in a dense nest of stars called a globular cluster. Previously discovered black holes are either similar in size to a large star, or super massive holes which are millions of times bigger than a star is able to remain stable. This finding indicates there may be an intermediate size range of holes residing within these star clusters.

First of all, the author is incoherent. He meant to say all confirmed black holes are either comparable in mass to something ten times more massive than the sun (give or take a factor of a few), or are larger than about a million times the mass of the sun (these latter ones are known as Supermassive Black Holes, and are found at the center of just about all galaxies, including our own). All black holes are stable, regardless of size. The observation here reports on what is known as an Intermediate Mass Black Hole, which is somewhere in the neighborhood of a few hundred to a thousand times the mass of the sun. The leading candidate host site for these IMBH's, as they are known, has long been globular clusters, groups of anywhere from tens of thousands to about a million stars that look like this [click on the link!]. A search of the leading astronomy database returns 77 hits for the terms "globular cluster" and 'intermediate mass black hole" both appearing in the same abstract over the past four years, including one by the author of this paper, my former advisor, and a number of my former colleagues suggesting that there was a growing consensus we'd find black holes like these in place just like where they looked. From what I can tell, the press release botches what could be called the "king of the mountain" phenomenon: the biggest black hole in a cluster tends to eject all the others near it, but nothing can knock out the biggest one, which ends up falling to the center of the cluster, as they found here. The breathless headline is one of the few I've ever seen in the sciences to use a strawman argument, "some computer models", and does it just about as successfully as your standard political strawman, "some liberals suggest that...".

Good astronomy: the wonders of the cosmos

At a discussion today of teaching the night's sky, I was reminded of how nice it is to take a moment now and again to really look at the sky. Many people assume that they live in places too bright to see anything, but they are actually running into a problem of patience. It takes your eyes a little while to adjust to darkness by having your pupils dilate fully. Until they do, your night vision won't be that good. Thus, next time you decide to look up, try to find a spot without streetlights directly in your line of sight, and wait a minute or two. You will find the sky contains a lot more than you thought it did. While it may be tough to see all that much in the middle of a city, I've seen numerous meteors on the North Shore of Long Island (hardly an ideal viewing location), and the view from the Berkshires is absolutely stunning, with the Milky Way visible as a hazy band running across the sky and clusters of stars making it hard to determine which are the Pleiades. Even in a city it is trivial to find a planet or two so long, assuming you can find an open patch of sky to the east, south, or west.

Still, it is dark skies that really seem required for feeling the full distance to our nearest celestial neighbors. In the Berkshires and Arizona, to name two that I've enjoyed, stars feel millions of miles away (this is a radical underestimate), and it is very hard not to feel correspondingly small. This is good for the soul; we go through life with a magnified sense of our importance, humanity's importance, the Earth's importance. Sometimes it is useful to remind yourself that just one star over, no one really gives a hoot. We are transient creatures, on a realtively small planet with a funky atmosphere, liquid water on the surface, and not too much else of note. It makes it all the more impressive that we've managed to come so far so fast (only a few hundred million years of evolution since our ancestors were protozoa). Someday in the future, we might actually travel to one of these, traveling almost one one-hundreth of one percent across the galaxy towards the furthest stars we can clearly resolve on a dark night. It's amazing just to think about it.