Staring into space

But what to look at next? The Hubble people had to pick targets to demonstrate the revamped telescopes abilities. They would call these images the Early Release Observations,or ERO at NASA,everything has an abbreviation. They wanted to produce pictures with lots of their term Wow Factor.

The rollout came in early September at NASA headquarters in Washington. Two huge flat-screens flashed fancy graphics. After much hoo-ha and throat-clearing,the moment came. The ERO! The journalists pounded out their stories,which all said pretty much the same thing: Wow.

You see the danger here: Wow can turn into Whatever. So heres our challenge: Well go back and look once again at these new pictures,but this time well probe deeper and search for any messages in the light that careens into Hubbles mirror. Well do a deep reading of the cosmic text. And well ask the hard question: What is space telling us?

Lets start with the Butterfly Nebula,technically known as Planetary Nebula NGC 6302. Its so delicate,so sublime. You can see it fluttering through space. The Butterfly Nebula is the product of a star in its death throes. The star is about 3,800 light-years away,in the constellation Scorpius. Those wings are actually hot streams of particles being ejected by the star into interstellar space. As the star starts to run out of hydrogen and helium fuel,its core contracts,and,simultaneously,the intense radiation of the star blows the outer layers into space. Its not an explosion but more of a spewing. Here,the star itself is unseen,obscured by dust. The dust and slower-moving gas form a torus,like a napkin ring,which forces the spew to be conical rather than spherical. Before the rise of scientific astronomy,stars were boring. No one knew that a star and our sun were the same thing. And yet the butterfly tells us the truth: The universe is wild. The universe evolves,and change is the norm. Theres something of a cosmic ecosystem out there. And the death of a star is cosmic fertiliser.

Next up,the stellar jet in the Carina Nebula. This is a double image that tells us that theres no single way that the universe looks. The top image shows a star-forming gas and dust cloud as seen in visible light. The bottom image shows the same structure as seen in infrared light. If Earth were directly in the path of a relatively nearby stellar jet,it would be lights out for all of us. Ditto if we were close to a supernova or to two super-dense neutron stars colliding and emitting a burst of gamma rays. The universe is violent. Almost every galaxy has a black hole at its core. At the centre of our galaxy,which we call the Milky Way,theres a black hole with the mass of millions of stars. Fortunately,thats about 26,000 light-years away. Were in Sleepyville.

A light-year is about 6 trillion miles. The cloud were looking at in the Carina Nebula is about three light-years from top to bottom. Earth has a diameter of about 8,000 miles,so if Earth were in this picture,it would be imperceptibly tiny. Other than some dust here and there,the universe is fundamentally transparent. This is why astronomy is possible. You can see stuff far away.

Now we come to the globular star cluster Omega Centauri. And thats a lot of stars. This single image shows a region containing about 100,000 stars,out of roughly 10 million in the globular cluster. The stars are different colours because they have different masses or are at different stages of their lives,which affect their temperature and brilliance. In a sense,this image of the Omega Centauri cluster is a chart of star life. Until the late 1800s,scientists doubted that Earth had been around for billions of years because they couldnt see how the sun could be on fire for such a long time. But its not on fire. A star is a fusion reactor. Life on Earth can evolve for a long time because stars are fairly efficient at transforming matter into sunshine.

Its hard to look at the Omega Centauri image without thinking,we are not alone. How could we be? The universe is so flamboyantly abundant and huge and awesome. J. William Schopf,a legendary UCLA professor who studies the origin of life,says: I find it really,really difficult to imagine that the universe is not teeming with life. I dont know about intelligent life,but I think there must be a bunch of that out there,too.

The final picture is called Stephans Quintet. At first glance,it looks like four galaxies,but then you see that the central object is two merging galaxies,with two galactic cores,like a double-yolk egg. The four orange-yellow galaxies will probably merge into a single galaxy; the blue-white galaxy is much closer to us and just happens to be in the line of sight of the other four.

But wait: There arent just five galaxies here. There are hundreds of them. Only the round objects with X-shaped spikes are stars. Most of the other dots,streaks and smudges are distant galaxies. This is,in a sense,a four-dimensional scene. With this two-dimensional image,were looking at three-dimensional structures,but were also looking back in timethe fourth dimension. Each layer of the image represents a different epoch of cosmic history. We see the faintest galaxies as they were billions of years ago. To me,its like a geologists core sample, astronomer Eric Chaisson of Tufts University says of the image.

This has been humbling,this investigation of space. Even the matter were made of,the ordinary protons and neutrons and electrons,is trivial,compared with the much more abundant dark matter that weve yet to detect directly but are certain is out there.

But wait: Perhaps were just getting started. Well star-trek across the cosmos! Well seed the universe with human intelligence and meet fascinating alien races and,occasionally,you know,mate with the ones with nice tentacles. The problem with this scenario is that NASA has put the Buck Rogers stuff on hold for the moment. Costs too much. Nowhere to go thats worth the trip. We could fly to the moon,but we already did that they say. We could head to a near-Earth asteroid,but that would be exciting only if NASA promised to blow it up on live TV. Mars is enticing,but a Mars mission is a budget buster. So,it doesnt look as if were going to be visiting Stephans Quintet anytime soon.