Science Musings Blog

Each week I receive via email Sky & Telescope Magazine's free Skywatcher's Bulletin. It provides a good summary of any interesting celestial events for the coming week. The bulletin provides an excellent starting point for beginner stargazers looking for guidance on what to look for under a canopy of stars.

This week's bulletin sent me out into the cold New England air last night in hopes of spying Comet Machholz. By star-hopping from Aldeberan, I soon spotted the comet in binoculars. It appears as just a fuzzy patch of dim light. Nothing spectacular.

Standing in the cold, looking for a run-of-the-mill comet, may seem like an pointless exercise to some. The joy in such an endeavor, of course, is actually finding something so nondescript and recognizing in the mind's eye what it represents. This dim smudge of light is in fact a large ball of dust and ice hurtling through the inner solar system on a highly elliptical orbit. Its visit in our sky will be short before it recedes in the vastness of space. While it was here, I can say I saw it. There's some pleasure to be derived in that...I think...

Took the grandkids back to the bat caves yesterday, a secret Tom-Sawyerish place on the back side of the island. The bat colony in the upper cave has pretty much vanished this year, just a few old "grandfather" bats hanging out by themselves. The colony in the lower cave is thriving. I'm sure the bats don't appreciate us awakening their pitch-dark daytime slumber.

The floor of the cave is deep in guano, decorated with the wings of hundreds of giant bat moths (Noctuidae), a big black insect with a six-inch wingspan that flies at night -- obviously a favorite food of bats.

The moths are called "bat moths" not because they are bat food but because they look like bats as they flit around at night. The locals call them money bats because of the intricate currencylike designs on their wings. In Cuba they are called brujas, witches, and considered to be spirits of the dead.

Bat moths love sweets. They have perched on the rims of our wine glasses as we sit on the terrace in the evening.

This is the week each year I traditionally peruse Guy Ottewell's Astronomical Calendar for the coming year, to prepare myself for the many pleasures the sky will offer. This is the book I recommend to friends and strangers more often than any other.

Guy has a gift for the graphic presentation of astronomical events -- comets, eclipses, occultations, conjunctions, meteor showers, you name it. Skywatching without Guy is like going to a play without a program. His annual inside-the-cover essay alone is worth the price of the book (a large format 80-page compendium).

And while you are ordering your copy, check out Guy's homepage for his many other publications. He is quite simply one of the cleverest guys around.

Yow! Take a look at this. After almost a year roving the surface of Mars, the Opportunity rover has approached the remains of it's discarded heat shield. The shield detached from the descending rover moments before landing and crashed down onto the surface of the Meridiani Plains.

For more good stuff like this, be sure to watch Nova on PBS, January 4th. They will be airing Welcome to Mars, a follow up on their terrific program of last January, MARS Dead or Alive. It should provide a good overview of the hugely successful Mars Expedition Rover missions.

These islands are riddled with caves and sinkholes. During the last ice age the sea level was much lower than today, and rainwater percolating down through porous limestone dissolved underground cavities and channels along faults and fissures. The roofs of some of the larger cavities collapsed to form sinkholes.

Yesterday we found deep in the bush what I believe to be the biggest sinkhole on Exuma, perhaps a hundred meters across and ten meters deep. We climbed down the wall to find a unique flora of giant ferns, soaring fig trees, and air plants. A journey to the Lost World.

Tom's post on the Asian tsunami has me involuntarily glancing out the window at the sea. Here on the island of Exuma in the Bahamas, we are only a few dozen feet from the shore and about 10 feet above sea level -- highly vulnerable to a wave such as the one that devastated communities along the Indian Ocean.

Fortunately, if history is a guide, we don't have much to worry about. In the 500 years since European colonization, there have only been about a half-dozen recorded tsunamis in the Caribbean region, with a total of about 50 deaths. Most were caused by local earthquakes, but one resulted from the Great Lisbon Earthquake of 1755.

The latter quake occurred on an active fault in the Atlantic off Portugal and is sure to be repeated, although no one knows when. As for the predicted Canary Island landslide, triggered by a volcanic eruption, well, there's quite a bit of controversy about that. A possible meteorite impact in the Atlantic, although utterly certain to happen someday, won't keep me awake at night.

But storm surges due to hurricanes, now that's another story. Hurricane Andrew in 1992 caused surges in these islands of over 4 meters. The old folks here still talk about the 1926 hurricane that sent waters 5 or 6 meters deep across Exuma.

The reports of the devastation caused by the tsunami in south east Asia are truly depressing. The massive tidal wave was the result of an undersea earthquake off the coast of Sumatra. The ocean floor suddenly ruptured and rose up sending an enormous swell of water northwards toward India and Sri Lanka. Those unlucky souls by the coastline had little or no warning of the impending wave.

Could something like this happen to the United States? Some scientists report that a powerful volcanic eruption in the Canary Islands off the coast of Africa could trigger a tsunami which could devastate the east coast of the U.S.. In such a scenario, a 50 meter high wave would reach New York City about 8 hours after the eruption, completely subsuming the city.

Is it time to sell your beach front property? No, although this kind of tsunami is possible in the Atlantic, it's highly unlikely to occur in your lifetime.

On the other hand, newly discovered asteroid 2004 MN4 is currently estimated to have a 1 in 37 probability (!) of striking the Earth in 2029. Yikes!

Boxing Day morning, the day after Christmas (actually two days this year, since the next day was Sunday), the island celebrates with a uniquely Bahamian pre-dawn celebration of music, dance and extravagant floats and costumes. A full moon in the west and Venus and Mercury in the East , all framed by dramatic moonlit clouds, made the morning especially memorable.

The two planets appear to draw closer. Actually they are 50 million miles apart along the same line of sight.

I thought I would share my artist sister's Christmas e-card. Her sources of inspiration are rather more eclectic than mine, ranging from eastern religion to Buckminster Fuller. She is an avid reader of Scientific American, and science often figures in her work.

Here she takes off from the information that "Five million high energy solar neutrinos pass through every square centimeter of your body every second." The neutrinos have their origin at the center of the Sun, where hydrogen nuclei fuse to form helium, turning part of their mass into pure energy. Neutrinos are a byproduct of the reaction. They pour out of the Sun in every direction (they hardly interact at all with matter), race across space and pass through the Earth "like dustmaids down a drafty hall." During the day they pour down through your scalp. At night, they pierce you from underneath the bed.

When we built our house on the beach in Exuma, we added a screened porch off the bedroom facing southeast. I had spent thirty years looking unsuccessfully for the green flash -- a blaze of emerald light that can sometimes be seen just as the sun is rising or setting over a sea horizon -- and I was determined that this would be the place to see it.

And I did. Many times now. But the practice of getting up before the dawn remains. There is no more perfect time of the day, in my opinion, especially in the tropics.

Over the next week or two I will watch Venus and Mercury almost kiss in the predawn sky, with Mars and Jupiter looking on approvingly.

On the low cliff down along the beach, the rock has broken away revealing...a plastic bottle!

I would have thought these sandstone cliffs were at least some tens of thousands of years old, perhaps deposited as windblown inland dunes during the last ice age, when the sea level was lower. and the islands of the Bahamas were considerably larger.

Can sand consolidate so fast, and in the face of the sea? I await the comment here of my soft-rock geologist daughter.

OK, so George W. Bush is Time's Man of the Year. That was predictable.

What was Science magazine's Scientific Breakthrough of the Year? That's a no-brainer too. The two Mars rovers, Spirit and Opportunity.

The plucky robots dropped onto the surface of the red planet, took a few big bounces, and got right to work. Opportunity was especially lucky, finding itself among rock outcrops that offered convincing evidence of a previous water environment on Mars.

The real significance of the story, says Science, is the demonstrated value of robotic space exploration. There is now even talk of using a robot to rescue the aging Hubble Space Telescope.

And what was the magazine's Science Breakdown of the Year. Another gimme. Increasing tension between the scientific community and the Bush administration and its Evangelical constituency.

Our feeder is up and we are open for guests.

No other bird can perform their tricks of flight - flying backwards, hovering in place. It takes energy for a hummingbird to move its wings so fast - an invisible 80 beats per second, which is why it must consume its weight each day in nectar -- or sugar water.

I never cease to wonder at the innate system of chemical command and control that lets the bird perform a dozen intricate maneuvers more quickly than I can turn my head. Every cell of the hummingbird's body is a buzzing conversation of proteins, speaking a language of shape - shapes as various as the words in a human vocabulary.

"The power of the visible is the invisible," said poet Marianne Moore. The sleek, iridescent body, the soda-straw beak, the whirring helicopter wings. What we see is dazzling enough. What we cannot see is even more dazzling.

My paleoclimatologist daughter has cautioned me about my recent post on global warming. Yes, most scientists agree that climate is warming, she says, but it's impossible to say how much of the warming is due to humans. Maybe 5%, maybe 75%; it's hard to say.

She also suggests that the Kyoto Protocol is a drop in the bucket, and would probably have little noticeable effect on climate. Does that make Kyoto political, as the Bushies say? Maybe, she says.

My own gut feeling is that the recent warming trend is almost certainly human-induced; call it circumstantial evidence. But she's the expert, so let's say "case unproved." We agree that government-mandated conservation can't be a bad thing.

If you are looking for the perfect gift for the space nut on your list -- or for anyone who appreciates the sheer beauty of the universe -- check out this week's Musing.

Often when I'm sitting on our terrace here, looking out into the Atlantic, I wonder what it must have been like on October 12, 1492, when the Lucayan people of the Bahamas saw what must have seemed like winged gods come sailing over the horizon.

Nothing in their experience could have prepared them for what they saw, and perhaps never before or since in history have two so different cultures clashed.

The Europeans had sailing ships, steel blades, gunpowder, germs and militant religion. The peaceable, gentle Lucayans lived a Club Med sort of life, with shell beads, pointed sticks, and no metal (except perhaps a few imported gold trinkets).

At the time of first European contact, there were perhaps 50,000 to 80,000 people living in the Bahamas , about the same density as today, excluding the urban centers of Nassau and Freeport. The people were the only useful resource of these scruffy, carbonate islands. They were rounded up by the Spaniards to work as slaves in the gold mines of Hispaniola and the pearl fisheries of Venezuela, where they died of malnutrition, harsh treatment, or European diseases.

Within twenty-five years, not a single Lucayan remained alive and the islands were deserted.

Since my last post I have translated myself 1300 miles south and sixty degrees up the temperature scale. I am on an island in the southern Bahamas, with a dial-up connection to the internet. One gets used to wireless, broadband.

On the other hand, I love life here without a TV. Working with hand tools. No answering machines. All of that by choice. The only two accouterments of modern times I can't do without are my PowerBook and my iPod. Words and music.

And, of course, a dark night sky.

So expect some tropical Musings for the next several months.

The chicken has now become the first bird to have its genome sequenced.

Direct descendants of dinosaurs, birds diverged from our own ancestors more than 310 million years ago. The chicken genome is only about a third the size of our own, but contains approximately the same number of genes. About a fourth of the chicken's base-pair sequences are similar to those of humans. These genes are most likely associated with function rather than form.

By function, of course, I don't mean hen parties, playing chicken or crossing roads. I'm taking about the basic chemical machinery of life that lets an adult creature develop from a single fertilized cell, and then maintains it (more or less) intact for the allotted number of years.

When a visitor asked the 15th-century zen master Ikkyu the meaning of life, the master responded, "Attention." "Is that all?" the visitor reiterated, inpatient. "Attention, attention," said Ikkyu.

"Attentiveness is the natural prayer of the soul," wrote the 17th-century philosopher Nicholas Malebranche. "To pay attention, this is our endless and proper work," agrees the contemporary poet Mary Oliver. "I don't know exactly what a prayer is," she writes in another poem; "I do know how to pay attention."

Sounds so simple, but so hard. To stay awake. To see the flower in the crannied wall, the grain of sand. To listen to the almost inaudible glide of black water under the bridge, the tip-tip of the nuthatch.

The world is inexhaustibly strange, beautiful, terrible. John Ruskin wrote in Modern Painters: "The greatest thing the human soul ever does in this world is to see something, and to tell what it saw."

As recently as last week the Bush administration was still insisting that the Kyoto Protocol on reducing greenhouse gases was based on politics, not science. This is nonsense.

The ever-growing scientific consensus on global warming is clearly expressed in the reports of the Intergovernmental Panel on Climate Change. The American Meteorological Society, the American Geophysical Union, and the American Association for the Advancement of Science have all issued statements asserting that the evidence is compelling for human modification of climate.

There is room for honest disagreement on what to do about global warming, but to suggest that the scientific community is divided on the reality of human-induced climate change is disingenuous. The concensus may not be universal, but it is overwhelmingly lolpsided.

My Musing this week is about a possible Irish record of the 1054 A. D. supernova, the progenitor of the famed Crab Nebula, as discussed by Irish scholars Daniel McCarthy and Aidan Breen. Here is another celestial event they discuss.

On May 1, 664 A.D., a total solar eclipse occurred in northern England. The track of darkness was centered upon the town and monastery of Whitby, site of the famous Synod of Whitby, at which King Oswy of Northumbria aligned the liturgical practice of the Celtic church with Rome.

Here is the Whitby eclipse as viewed by my Starry Night Pro sky simulation software. The Sun and Moon were in Taurus. That's the Hyades to the left, the Pleiades to right, and Mercury below.

McCarthy and Breen believe the the synod was called in that year and held in that place because the eclipse was taken as a sign of imminent Apocalypse. Presumably, King Oswy wanted to get his spiritual ducks in a row before he met his Maker.

As I say in my Musing, nature will always provide signs and portents to minds predisposed to superstition.

It was a story that barely made a blip in the national media so I'd like to give a little tip of the hat to a personal hero of mine -- NASA astronaut John W. Young. This past week he announced his retirement from NASA at the age of 74 years.

Young began his career at NASA in 1962 when he was selected to be among the second group of astronauts (after the Mercury Seven) in the fledging U.S. space program. His first flight into space, in 1965 during the Gemini program, was with another NASA legend, Gus Grissom.

Later during the Apollo program, twelve Americans became the only human beings in history to walk on the surface of another world, the Moon. John Young was one of them as commander of Apollo 16 in 1972.

When the Apollo flights came to an end and NASA began the transition to the Space Shuttle era, most of the veteran astronauts left NASA and enjoyed successful careers in the private sector. John Young stayed on and continued to serve his country.

In 1981, on the first space shuttle flight, Young was at the helm as commander of the Columbia. This was followed by a second Shuttle flight in 1983.

Even after his flying days were over, Young continued at NASA working as Chief of the Astronaut Office.

At the end of December, Young will end his 42 year career at NASA leaving an incredible legacy which includes two flights to the Moon and two generations of admiring space fans, myself included.

A few days ago my wife spotted an unfamiliar bird at our bird feeder. We pulled out our Stokes guide and identified him as a male Red-Bellied Woodpecker. I mentioned seeing it to the expert bird watcher in our family, Chet. I was delighted to discover that he had never seen one in Massachusetts.

My curiosity piqued, this led me to a Google search where I discovered a terrific website called eBird.org. Run by the Cornell Lab of Ornithology and the National Audubon Society, eBird allows birders from across the country to record their observations in one central database.

Red-Bellied Woodpeckers are common in the Southeast United States, but are slowly moving north. According to observations submitted to eBird, Massachusetts is now at the northern boundary of their range.

Using their mapping tools I discovered that the last reported sighting of a Red Belly in my area of Massachusetts was in October. I dutifully reported our sighting using their submission form. I will keep a look out to see if he returns to the feeder...

A cute little graph in the January Scientific American show the exponential increase in computing power since the first digital machines of the 1940s.

The Mac G5/Dual 2.0 GHz computer is now at the top of the desktop line, executing 10 billion instruction per second. This is about the brain power of a guppy, says roboticist Hans Moravec. Extend the graph and you reach the processing equivalent of the human brain in about 2040.

I figure my kids will take the car keys away from me in about 5 years. By 2040 we will have cars that drive themselves, more reliably than you or me, to wherever we want to go, unassisted, through heavy traffic. I was born about 30 years too soon.

There are tens of trillions of cells in my body and every one of them has about an arm's length of DNA, packed as 23 pairs of chromosomes. Now I know it sounds impossible that molecules several feet long could be packed into the nucleus of a cell too small to see with the eye, but take my word for it, I've done the math, and it fits nicely.

Each strand of DNA is terminated at both ends by a sort of aglet (the little plastic cap on the ends of shoe laces), called a telomere. The telomere insures that the meaningful part of DNA is accurately replicated.

Each time a cell reproduces the telomere gets a bit shorter, and many biologists believe that's one reason we age. All those DNA shoe laces unraveling at the ends.

Now they tell us that the integrity of telomeres is diminished by stress. No surprise there, but I can feel my aglets peeling away even as I write. Just thinking about those diminishing telomeres is stressing me out.

My new novel has just been published in Ireland/UK, a love story of the physician Valentine and blind Julia, set in the 3rd-century Roman Empire. Yes, this is the man who gave his name to lovers, but not quite the saint you expect. The novel addresses many of the themes of Science Musings: reason vs. superstition, empiricism vs. revelation, naturalism vs. supernaturalism. For the time being, you can get it through AmazonUK.

In his book The Future of Life, biologist E. O. Wilson suggests that we are hardwired for the nearby and the short term.

"The human brain evidently evolved to commit itself emotionally only to a small piece of geography, a limited band of kinsmen, and two or three generations into the future." Anything else was counterproductive from a Darwinian point of view.

If Wilson is right, it is against our biological nature to worry about rain forests in Bolivia, higher sea levels in 2100, or AIDS in Africa.

Our capacious, adaptable brains may not have evolved to take the wide, long view, but they make it possible to do so. Our higher human nature is to transcend our biological nature.

1. The universe is big. Human space is not cosmic space.

2. The universe is old. Human time is not cosmic time.

3. The universe evolves -- galaxies, stars, planets, life, consciousness.

4. The universe perceived by the senses is all we can know. The more we learn about the universe -- including ourselves -- the more we understand the depths of our ignorance.

5. The more we learn, the more we appreciate the universe as the revelation of a Mystery worthy of our wonder, awe, reverence, praise.

I'm a bit late posting my Musing this week. I was traveling over the weekend, to see my Mom in Chattanooga. As I passed through the airport last evening I noticed that Newsweek has a cover story on The Quest for Memory Drugs. A timely connection to my Musing.

Tomorrow morning looks like a washout for the Jupiter occultation here in New England. Check the weather report for clear skies in your area. For you folks out west the show will be over by the time the Moon rises.

Meanwhile, at Saturn, Cassini is in the middle of her second orbit of the ringed planet. The images released by the Cassini team this past week or so have been incredible. Included are intriguing views of the moons Titan, Tethys and Rhea. But most stunning is a color view of the tiny moon Mimas against a backdrop of enormous ring shadows. Wow!

A heads up for observers in the Eastern U. S. and Canada. The moon will move in front of Jupiter during the predawn hours on Tuesday, December 7, high in the southeastern sky. In the Northeastern Corridor this will occur between about 4 and 5 AM. You can check for exact times at Sky & Telescope's website.

You'll want to get out at least a half hour before the occultation begins to see the crescent Moon almost on top of bright Jupiter, then watch as the Moon devours the planet. About an hour later Jupiter will emerge from the dark limb of the Moon.

California reader Jennifer shared by e-mail some photos taken on a recent hike into the Sierras, including this one of glacial gouging and polishing of rocks where no glaciers exist today.

In the fall of 1831, young Charles Darwin accompanied his geology teacher Adam Sedgwick on a field trip to the mountains of North Wales. Half-a-century later he wrote: "We spent many hours in Cwm Idwal, examining all the rocks with extreme care, as Sedgwick was anxious to find fossils in them; but neither of us saw a trace of the wonderful glacial phenomena all around us; we did not notice the plainly scoured rocks, the perched boulders, the lateral and terminal moraines. Yet these phenomena are so conspicuous that...a house burnt down by fire did not tell its story more plainly than did this valley."

We only see what we expect to see. Because the theory of the ice ages had not yet been invented in 1831, Darwin and Sedgwick were blind. Later, with a theory in mind, the evidence of ice was obvious and irresistible.

Notre Dame Magazine has asked me to write an article on geneticist Dean Hamer's fine little book The God Gene: How Faith Is Hardwired into Our Genes.

Hamer claims to have identified a gene, rather prosaically called VMAT2, that appears to be related to spirituality.

It is not faith in God that the gene correlates with, but a trait called self-transcendence, a feeling of connectedness to the universe and everything in it. Self-transcendent people may or may not believe in God.

I look forward to the assignment. For the moment, in preparation, I am reading again a book I first read almost half-a-century ago, as an intensely religious undergraduate, William James's The Varieties of Religious Experience, a work that stands at the root of all attempts to trace the natural origins of religion.

Here is a re-creation of Galileo's view of Jupiter. This is what he would have seen on the evening of January 7th, 1610.
Jupiter and Uranus are about 2.5 degrees separated in the sky--about two fingers width held at arms length. The small circle is the approximate field of view of Galileo's first telescope. I think we can forgive Galileo not spotting the undiscovered Uranus. What he saw through his eyepiece, moons orbiting another celestial body, was the discovery of a lifetime and literally an earth-moving event.

My daughter on the phone this evening: "Pop, what are the zillions of little brown moths around my house? They are everywhere!"

Yep, and they've been an early winter fixture for a few years now. Only the males have wings, so it's the boys you see frolicking at your back door. The larvas will raise havoc in the spring.

Apparently, these are a European invader, and have no natural enemies here. If you live in eastern New England, get used to them.

The smallest shadow is Io's. The shadow at Jupiter's left edge is Ganymede's. The shadow at the right edge is Callisto's. Callisto would be a few inches off to the right of its shadow.

Back in 1988 I had a program called MacStronomy for my Mac Plus (my third Mac!) that I used to recreate Jupiter's position in the sky in the winter of 1609-10 when Galileo first observed Jupiter's moons. I noticed that the yet undiscovered planet Uranus was only a few degrees away, and easily bright enough to have been visible in Galileo's scope. It was one of the brighter objects in that part of the sky. Was Galileo the first to see Uranus? Unable to resolve its tiny disk, he would have thought it to be a star.

I had a little note on this published in Sky & Telescope in February 1988.