Bang, Or No Bang?

Science can be great. The world of science, in most cases, allows for vigorous debate, even about the most fundamental, basic, long considered to be settled concepts–and as new data comes in, the process happens over and over again. Sometimes the novel theory actually topples the old assumptions–as when Copernicus argued that the Earth revolves around the Sun, or Einstein’s thought experiments and calculations dislodged Newtonian theories about gravity. At other times, the new theory is shown to be a bunch of hooey, and the product of shoddy science and cherry-picked data.

There’s a vigorous argument along those lines going on now in the world of astronomy and cosmology. The issue is whether the incredible photographs being produced by the James Webb Space Telescope are inconsistent with the “Big Bang” theory–the widely accepted concept that the universe started billions of years ago with an enormous explosion that occurred everywhere at once and has been expanding in all directions ever since.

An article published in early August argued that the Webb telescope photos are inconsistent with the Big Bang theory because the distant galaxies shown in the photos look different than what the Big Bang theory predicts. Other scientists reject that argument as science denialism; they note that while the Webb telescope images of faraway galaxies show structures that are more evolved and coherent than was expected, that result does not undercut the Big Bang and in fact is consistent with the theory. As one article published earlier this month on puts it: “The surprising finding that galaxies in the early universe are more plentiful, and a little more massive and structured than expected, doesn’t mean that the Big Bang is wrong. It just means that some of the cosmology that follows the Big Bang requires a little bit of tweaking.” 

The constant revisiting and revision of theories as new data comes in is what makes science so cool. The Webb telescope, the data it is gathering, and the discussion it is generating, are doing exactly what the process of science contemplates.

The Webb Space Telescope Delivers

This week NASA released the first images captured by the James Webb Space Telescope, and it is pretty amazing stuff.

The Webb Telescope is a joint effort by NASA, the European Space Agency, and the Canadian Space Agency. From its position far out in space, without having to peer through the Earth’s atmosphere, the Webb Telescope can see infrared light that is not detectable by the human eye and can position its powerful mirror assembly to peer into the deepest recesses of the universe. The images from the first five targets of the Telescope show its versatility; they range from a look at objects that are basically in our stellar neighborhood, only a few thousand light years distant, to a look at SMACS 0723, a cluster of galaxies that are 4.6 billion light years away.

And we can give NASA and its partners credit for a bit of whimsy in their choices, too. They decided one of the targets should be a cluster of galaxies called Stephan’s Quintet–familiar to anyone who has watched It’s A Wonderful Life as the home territory of the angel Clarence–and the image at the bottom of this post shows how the galaxies interact with each other and form new stars in a kind of exquisite gravitational dance.

My favorite images from the first five targets are of the amoeba-like Southern Ring planetary nebula, shown above. The nebula, which is a mere 2,500 light years from Earth, was formed by shells of gas and dust that were ejected by the two dying stars in the center of the array, shown clearly in the photo on the right. Carl Sagan would call the wispy material radiating out into the void “star stuff,” and it’s breathtaking to see.

The Webb Space Telescope has just begun its operations, and its five targets are only a tiny, infinitesimal part of the universe that the telescope will be exploring. Simply put, there’s lots to look at. Prepare to be amazed.

A Supernova In The Offing?

The red giant Betelgeuse — don’t say it three times in a row unless you want Michael Keaton to show up and make your dinner guests dance to the Banana Boat Song — is one of the most familiar stars in the sky for people who live in the northern hemisphere.  It’s the right shoulder, and one of the brighter stars, in the constellation Orion, the hunter, which is visible even in the night sky of Columbus, with all of its light pollution.

betelgeuse-rigel-orionBut lately, Betelgeuse is acting strangely.  It’s become noticeably dimmer, and fallen out of the ranks of the top ten brightest stars in the northern sky.  That might mean nothing, because Betelgeuse is a variable star that shifts in brightness, or it might mean something extraordinary:  some scientists think we might be witnessing the death throes of Betelgeuse, and in short order we might see a supernova where Betelgeuse once was.  Supernovas occur when the lifecycle of a star of a particular size ends, and the star’s mass is ejected in a titanic explosion.  If Betelgeuse were to go supernova it would be brighter in the night sky than the Moon and might even be visible during the day.

Supernovas don’t happen every day, every decade, or every century.  One famous example occurred in 1054 A.D., when Chinese, Japanese, Arab, and Korean astronomers all reported observing a new star in the heavens, in the constellation of Taurus the bull, that was so bright it could be seen during the day for weeks and did not fade from view at night until two years later.  Modern astronomers believe that the ancient astronomers were seeing a supernova that now appears as the Crab Nebula.  Being able to observe a supernova in real time, with the sophisticated technology that is now available, would undoubtedly allow humanity to add significantly to its understanding of the death throes of a star.

And here’s a mind-blowing point.  As I write this, Betelgeuse may already have exploded.  In fact, it might have already exploded when Columbus sailed for the New World in 1492, or the American Revoluation began in 1776, or World War II ended in 1945.  We don’t know for sure, because the light from Betelgeuse takes about 600 years to reach Earth.  Whenever you look up at the stars in the night sky, you’re always looking into the past.

The Bright Universe Below

IMG_1898Astronomers bemoan the amount of light produced by cities and suburbs at night. The bright glow from below interferes with their ability to see the stars above.

I saw a good example of the “light pollution” as I flew into Newark on a clear night earlier this week. Ironically, the light from the houses, parking lots, and shopping centers on the ground reminded me of the stars and constellations of the evening sky.

Alpha Centauri’s Earth-Sized Planet

Science continues to achieve amazing advances in our ability to detect, measure, and analyze planets orbiting stars far outside our solar system.

So far, scientists have discovered and confirmed the existence of more than 800 planets.  Most of the planets, however, are huge gas giants, like Jupiter or Saturn in our solar system.  The latest advance in detection capabilities came this week, when scientists announced that they have detected the lightest planet to orbit a Sun-like star — and the star just happens to be Alpha Centauri, a weird, triple-star system that is the Sun’s nearest galactic neighbor.

Alpha Centauri, for those who fell asleep during astronomy class, is a mere 4.3 light years away.  Of course, one light year is 6 trillion (6,000,000,000,000) miles away, but who’s counting?  The planet scientists have detected is about the mass of our good Earth.

Before you start worrying that little green men might appear on your doorstep tonight, take a deep breath:  the Earth-sized planet is closer to Alpha Centauri B than Mercury is to the Sun, so it’s probably not conducive to life.  Still, the discovery is remarkable.  In the not too distant future, scientists will use this detection technology to find a planet about the size and mass of Earth, orbiting a star a lot like Sol, at a distance that would suggest that it is likely to be temperate.  What will that mean?  My guess is that we will train every radio telescope and sensory device we have in the direction of that planet, listen as hard as we can, and hope.


Venus On The Move

Venus is on the move today and tomorrow.  It’s traveling slowly across the face of the Sun, on a journey that astronomers call being “in transit” — as if Venus were hopping a subway to get from one side of the solar system to another.

These kind of astronomical events are very cool, because they happen so rarely.  There’s a “music of the spheres” sort of celestial harmony to Venus’ journey that reflects a special, highly unusual confluence of positioning of the Sun, Venus, and Earth.  It won’t happen again for 105 years.  By then, we hope, the European debt crisis will have been resolved.  In fact, some astrologers are saying that the transit of Venus might help to solve such problems.  It’s is supposed to herald in a new era of spiritual and technological revolution . . . or, it’s supposed to strongly accentuate feelings of love and hate.  With astrology, it always seems to be one or the other.

As with any solar celestial phenomenon, the news stories always caution people not to look directly at old Sol.  It’s hard to believe anyone would try to use the naked eye to check out the Venus transit, because Venus will be only a small speck against the enormous disk of the Sun.  You supposedly can see it safely by creating one of those pinhole-in-a-box projectors that the news stories typically mention in these circumstances.  I tried to make one of those devices when there was a solar eclipse during my childhood, and I gave up in frustration when it didn’t work.  This time, I’ll just rely on the photos, and in the meantime wish Venus well on her cross-town travel.

The Coming Big Bang

The universe began with the Big Bang billions of years ago, and now astronomers say we’ll be dealing with another big bang — in about four billion years or so.

The coming big bang will occur when our galaxy, the Milky Way, collides with and merges into Andromeda, a neighboring galaxy.  The two galaxies are being pulled together by their mutual gravities, and in fact are rushing toward each other at the breathtaking speed of 250,000 miles per hour.  At such astronomical (pun intended) speeds, it’s hard to believe that all Earth-dwellers aren’t experiencing a touch of cosmic motion sickness.

Of course, galaxies are mostly empty space, so whoever is left on Earth when the galactic convergence occurs isn’t likely to see suns and planets smashing into each other.  But the night sky will look different.  Orion and Taurus and Ursa Major will have lots of company.

Trillions Of Planets, And Still Counting

Continuing developments in telescope technology are causing astronomers to increase their estimates of the number of Earth-like worlds in the universe.

The latest disclosure deals with the existence of “red dwarf” stars, which are dimmer and smaller than the Sun.  Until recently, telescopes have not been sufficiently powerful to detect such stars in other galaxies.  Enhancements to telescopes, however, have allowed astronomers to determine that red dwarf stars are far more common than was previously suspected.  Indeed, astronomers believe that such stars are 20 times more prevalent in older galaxies than in our galaxy.  As a result, astronomers also are concluding that there likely are many more Earth-like planets orbiting those stars — possibly trillions of Earth-like worlds.

Trillions of Earth-like planets?  The concept is provocative, because increases in the number of planets logically also increases the likelihood of life, and therefore intelligent life, on at least some of those faraway planets.  And the follow-up question is even more provocative:  would the existence of intelligent extraterrestrial life be good or bad?  Would we rather be the only intelligent life forms in the universe, or would we prefer to learn that we are not alone — indeed, that intelligent life is as common as the fish in the sea?  How comfortable would humans be with the knowledge that they live in a crowded neighborhood, where neighbors might drop in for a visit at any moment?

Unimaginably Distant, Unimaginably Old

The space-based telescopes keep making amazing discoveries.  The latest is the Hubble space telescope’s identification of the most distant galaxy ever detected — a galaxy that is more than 13 billion light years distant from Earth.  That means that the light we are seeing now has traveled for 13 billion years to reach our space.  In fact, the light we are seeing from that galaxy emanates from stars that blazed only 600 million years after the Big Bang.  Those stars almost certainly exist no longer, having long ago gone supernova or turned into one of the other stellar objects that are created when stars die.  In that sense, the Hubble telescope is a real-life time machine that allows us to peer into the distant past.

The Hubble space telescope

Astronomers will study the new discovery with great interest, because it may help to provide answers to some very provocative questions.  What was the life cycle of early stars, whose intense heat produced the heavy element “star stuff” (to use Carl Sagan’s phrase) of which our universe is made?  How did the earliest galaxies form?  Why is light from such galaxies visible through the “fog” of hydrogen that should have resulted from the Big Bang?

We can expect more amazing discoveries along these lines as new ground-based and space-based telescopes using new technology come on line and begin to probe the heavens.