September 3, 2011
Q & A With Stephen James O’Meara
In his new book, ℠Deep-Sky Companions: The Secret Deep,´ Stephen James O'Meara presents 109 new objects for stargazers to observe. The Secret Deep contains many exceptional objects, including a planetary nebula whose last thermal pulse produced a circumstellar shell similar to the one expected in the final days of our Sun's life; a piece of the only supernova remnant known visible to the unaided eye; the flattest galaxy known; the largest edge-on galaxy in the heavens; the brightest quasar; and the companion star to one of the first black hole candidates ever discovered. Each object is accompanied by beautiful photographs and sketches, original finder charts, visual histories and up-to-date astrophysical information to enrich the observing experience. Featuring galaxies, clusters and nebulae not covered in other Deep-Sky Companions books, this is a wonderful addition to the series and an essential guide for any deep-sky observer.Q: Dr. O'Meara, tell us about how you became interested in space, and what lead to this book.
A: I've been observing the heavens since the age of ~ 6 (almost 50 years ago), when my mother sat me on her lap and together we watched one of the reddest total lunar eclipses in the 19th century. The image of that blood-red Moon burned deeply into my soul and led to an immediate and uncontrollable desire to study the stars, which I did on my own until, at the age of 14, when I was given the keys to Harvard College Observatory in Cambridge, Massachusetts (where I grew up). I could use their telescopes for research as long as I operated the telescope for public open houses. And so began a long and fruitful career in sharing the wonders of the universe with the public.
The Secret Deep is the fourth and latest book in my Deep-Sky Companions series published by Cambridge University press. Each book spotlights 109 different deep-sky objects (galaxies, nebulae, clusters, and more) that sky lovers with small telescopes (and larger) can explore from the comfort of their favorite observing site. The series reflects my ongoing desire to share my love of the night sky with others; and I believe these books will help others do the same. Observing the splendors of the night sky can be contagious.
Q; Many of us live in urban areas where viewing the night sky is often difficult. Do you have any suggestions for us?
A: First, I'd like it known that I grew up in an urban environment, only 5 miles from Boston, Massachusetts. In the early 1960s, though, the Milky Way was still visible back then. But in later years, the Milky Way all but vanished from view, so I understand the urban observer's plight.
Of course, deep-sky objects are best appreciated visually under dark skies. And this requires travel for many observers who just don't have the sky. But many astronomy clubs/societies have dark-sky observing sites. Joining a club and sharing time under the stars with other observers can be a rewarding experience.
Of course, one of the growing aspects of amateur astronomy is CCD-imaging (electronic camera attached to a "go-to" telescope). With this setup, amateurs can beat light pollution and observe from the comfort of their own homes. Go-To telescope technology also eliminates the requirement for the observer to have to search for objects visually from light-polluted areas. With such a system, amateurs can create stunning images of the objects in my books. In fact, that's why I'm honored to have Mario Motta's CCd images gracing the pages of the Secret Deep. I've been sensitive to the ill-effects of light
pollution and am happy to see so many people in cities thriving in the hobby (and collaborating with professional astronomers) with their home setups.
Still, I love the visual view. Nothing can remove the magic of seeing the corpse of a dying sun, or the grandeur of a globular cluster with its symphony of starlight, or the graceful folds of a gaseous nebula. For me, seeing these objects with the eye somehow colors my soul. And I know I'm not alone
Q: With an eye towards the sky, why the interest in volcanoes?
A: I had a love of volcanoes arguably longer than the night sky; the interest dates, once again, to my very early childhood when my parents bought me a copy of "Dinosaurs: a Little Golden Book" published in 1959 when I was three. On the book's cover was a T-Rex chasing a Brontosaurus (now Apatasaurus) into a swamp. Behind T-Rex is the liquid fire of an erupting volcano. That red fire of prehistory and the red fire on the Moon had the same effect on me.
Of course, being a child in Massachusetts, I could look at the sky but I couldn't chase volcanoes ; So I began to pursue volcanoes (my other passion) once I became old enough to hop on a jet. Turns out that you'll find the darkest night skies in areas surrounding active volcanoes: for instance, my home in Volcano, Hawaii.
Q: Is there any truth to the idea that volcano eruptions are effecting the depletion of the ozone layer?
A: Yes! But it's a variable and usually short-lived phenomenon. NASA satellite studies of ozone depletion caused by the 1991 eruption of Mount Pinatubo in the Philippines, and Mount Hudson, in Chile, for example, showed a 15 to 20 percent ozone loss at high latitudes, and a greater than 50 percent loss over the Antarctic! So, yes, volcanic eruptions can play a significant role in reducing ozone levels. But, as I mentioned the effects are, overall, short-lived, so the ozone lost can recover to "normal" levels, but future eruptions will cause fluctuations. Also, I'd like to point out that we're living in a relatively volcanic quiescent period. We did not have the current technology to measure ozone depletion during eruptions of the magnitude of Krakatau, or Tambora, or Laki, all of which had large consequences on global climate (remember the little Ice Age?) That was volcanically induced.
Q: What makes it difficult for us to predict earthquakes and volcanic eruptions? We can pin point storms and hurricanes...
A: Well, we can see a storm forming and can watch its development with satellites and Doppler imaging, so we can, in a sense, dissect it inn real time and make accurate predications with decent probabilities. We cannot see into the earth and in real time see where magma is moving. We can only infer from instruments on the surface. Studying a volcano from the surface is like a doctor trying to tell a patient what's wrong with him or her just by poking the body or smelling one's breath. But volcanic prediction is much better than earthquake prediction. Until we find a way to monitor crustal stress at key locations and know the strength and weaknesses of the rock involved, we're at the mercy of natural forces taking action. The fact is we live on a dynamic planet.
Q: Can we at least use volcanic activity as some sort of indicator of future weather patterns?
A: Well, I don't know about future "weather" patterns, but certainly we have the capability of monitoring Earth's atmosphere. Not all volcanoes that erupt are sulfur rich. Although we can't look into a crystal ball and predict at this moment whether the Earth will warm or cool owing to volcanic effects, we can, once one of these scary volcanoes erupts, be able to monitor the aerosol output, then make predictions. It's a wait-and-see game at the moment. But at least we're on to it! And we're always learning.
For instance, a few years back, Robert A. Duncan, a professor in the College of Oceanic and Atmospheric Sciences at Oregon State University confirmed a link between massive volcanic eruptions along the east coast of Greenland and in the western British Isles about 55 million years ago and a period of global *warming* that raised sea surface temperatures by five degrees (Celsius) in the tropics and more than six degrees in the Arctic. The study documents the Earth´s response to the release of large amounts of greenhouse gases — carbon dioxide and methane — into the atmosphere, and definitively links a major volcanic event with a period of global warming.
As I mentioned earlier, volcanoes can also lead to global cooling: In 1783 the Laki Icelandic eruption caused the lowest-ever winter average temperature in 1783-84 (In the US & Europe), about 4.8ËC below the 225-year average. The culprit was the large volume of SO2 erupted during what is now considered one of the largest outpourings of fluid lava (like Hawaiian lava) in historic times. The SO2 created a volcanic smog that blocked out of sunlight leading to what we call haze-effect global cooling.
Then, there are effects beyond Earth. For instance, are you aware that Venus, Mars, Jupiter and Saturn (and maybe the other outer planets) are experiencing a period of global warming in concert with the Earth's? Spooky, huh?
Q: Definitely spooky! Other planets? Is it bunk that humans are causing the problems?
A: First, I misspoke about Venus (I meant it's already undergone global warming to the nth degree); no new studies on that.
Now, though it's true that some scientists have shown data to demonstrate warming temperatures on Mars, Jupiter, (Saturn? —— recent huge storm, weak evidence), Triton and Pluto, and argue that the warming trend appears to be solar induced, such claims have been controversial. Such is science.
I have no sage comments to offer on humanity's affect on the planet. I'm not an expert in the field. I've read arguments on both sides and have come to the conclusion that I'd rather bang my head against the wall. What I can comment on the Earth's past and what we know to be undeniable truths:
Prior to the industrial revolution and the combustion engine, the Earth has had periodic episodes of global cooling and warming —— every 100,000 years or so Earth's climate warms. The last "interglacial period" was about about 18,000 years (after the Pleistocene Ice cap) —— which is about how long they last on average.
That said, and humanity aside, I personally cannot disregard the possibility that the Earth might still be in an interglacial thaw —— before the next Ice Age hits! (How's that for a curve ball). You know, even Mauna Kea here in Hawaii was capped with a glacier in the Pleistocene Age! Or maybe the current warming trend is a rebound effects from the Little Ice Age combined with the human factor. I don't know, I'm just trying to stir thoughts into your mind for a night of reflection.
Q: In your book, you mention "the flattest galaxy known." Can you explain that?
A: Sure. The galaxy is NGC 4762 in Virgo. We see it perfectly edge-on. The galaxy spans 170,000 light-years in length but is only 40 light-years thick.
Q: What makes this book different from other books you have written?
A: Well, like the third book in the Deep-Sky Companions series, the list of 109 deep-sky objects is new and has never been published before. It includes many superlative objects for the visual observer or the CCD imager. All the objects in the book were imaged with a CCD camera attached to a home-built 32-inch reflector designed and owned by my friend Mario Motta in Gloucester, Massachusetts. Everything in the book —— Mario's photos, my drawings, the astrophysics, the history, the help on how to find the objects, and the detailed descriptions of each object as seen through telescopes —— works together to provide the observer an invaluable insight into the working of our universe, as well as a rich observing experience.