The Astronomy Fire Hose Continues to Flow

The press conferences at AAS meetings are always featuring cutting-edge science, attended by a really good press corps with members with very good science backgrounds. I remember attending a press presentation once that presented some very exciting science and good images. The topic was on black holes and the Q&A after the main presentation reminded me of a science colloquium back when I was in research. Very probing and astute questions were asked and the astronomers were kept hopping. After it was over, I overheard one of the presenters say to a colleague, “That was like defending my thesis!”

It helps that many scientists DO get into the swing of working with the writers, and work hard to give their stories good hooks that allow journalists to make the complex stories clear to their audiences.

One of my favorite stories/headlines from this meeting (so far) came this morning. The headline is SLOAN AND THE SEVEN – make that eight — DWARFS—Many More Predicted.” The story is that with Sloan Digital Sky Survey data, a team has been able to find a number of dwarf galaxies near our own Milky Way. This is great news, but there’s an underlying story that identifies dark matter (yes, that ubiquitous dark matter component of the universe) as a player in everything from the formation history of these dwarfs to their distribution (and possible links to our galaxy). It’s one of those headlines that fronts a multiple set of stories, all in one press release. So, speaking of cool headlines, Gemini Observatory (for which I do a lot of editing and writing work) put out a pair of press releases today. They describe some fairly complex science done with studies of rare abnormal stars in our own galaxy and a ring of warm material that is thought to be encircling the active galactic nucleus of galaxy Centaurus A (NGC 5128). The first one is Some Rare Abnormal Stars may have White Dwarf Parents. The story focuses on two types of stars that seem to have really high amounts of oxygen-18, a type of oxygen not often seen in stars.

The cute headline for Centaurus A and its circumnuclear ring was Small Warm Doughnut Feeds Theories of Extragalactic Black Holes. The story describes efforts to find a torus (ring-shaped object) around the center of this galaxy. It’s there because there are emissions that imply it’s there. But, no one has been able to “see” it, leading people to assume that it’s smaller than we can resolve with our existing telescopes. It’s important to find these rings of material because they can tell us a lot about what’s happening in and around the cores of active galaxies. And, it was fun coming up with a headline that would hook people’s attention to what might, at first glance, look like a story too complex to tell to a general audience. You be the judge—do the headlines help sell the stories?

Eavesdropping on the Universe

There’s a law of unintended consequences that seems to operate everywhere: if you find a way to do or discover something, there’s almost always another thing you can do or discover with your method. So, for example, when Ball Aerospace was developing detectors for an instrument on the Hubble Space Telescope that would look at distant objects bright in ultraviolet light, someone figured out that you could use the same detectors in another setting: to detect breast cancers. You’ve probably done something like that around your home—found a different use for a familiar tool. My dad used to tease us kids (I have five sisters and two brothers) that we could be fair mechanics, just using hairpins.

The image below is a shot of an array being built in Western Australia called the Mileura Wide-field Array (now renamed Murchisan Wide-field Array. A consortium of groups is working on this, including MIT Haystack Observatory near my home. I’ve been working with Haystack on some projects, and have been following the MWA with great interest.

MWA is being built to survey the sky at radio frequencies below 1.6 GHz. What can we see at these low frequencies? Since it’s located in a radio-quiet area (free of interference from our own radio, TV, satellite radio, military radars, etc.), this array is expected to see objects and events in the dynamic radio sky—the active cores of galaxies, for example, or variations in the light coming from quasars. It should be able to help astronomers detect signals from neutral hydrogen that existed back when the universe was being lit up by radiation from the first stars, more than 13 billion years ago—during a time called the “Epoch of Reionization.” (You can read more technical details about MWA at the Low Frequency Demostrator array pages.

So, what unintended consequences do you think might happen as astronomers use MWA to scan the universe? It turns out that the array will be sensitive to waves of light (particularly in radio and radar frequencies) that are streaming from other civilizations around any of the 1,000 nearest stars that happen to have intelligent life on them.

Astronomer Avi Loeb (of Harvard-Smithsonian Center for Astrophysics) and a team of researchers are proposing to use MWA to search between 80-300 MHz (wherein our civilization’s broadcast signals—including military radars— exist) to search for signals similar to those that WE put out to the cosmos. Dr. Loeb presented his ideas this morning at AAS, showing once again that when you build a tool for one purpose, even in astronomy, you can almost always find another equally good and pretty darned exciting use for it to make some cool discoveries. Stay tuned!