Hubble's Canvas

Hubble was created to dispense with the biggest problem in astronomy, the interference caused by earth’s atmosphere. The project was almost a failure because of a fatal problem with the camera, the lens was misshapen. A daring rescue turned a billion dollar failure into the most stunning instrument ever created for studying the universe. Universe in Bloom – Monet had his water lilies, Hubble has its planetary nebula, the most colourful, delicate and beautiful objects in the universe. Each of these cosmic butterflies is composed of a puff of gas, expelled and illuminated by a dying star. They come in a variety of shapes, which helps astronomers understand what the stars were doing in their final stages of life. They also seed the galaxy with the dust and molecules that will eventually become a part of a new generation of stars.

The universe paints pictures with light, so to understand what a Hubble picture can reveal about the universe, it’s necessary to understand how light is emitted, absorbed and reflected by stars, gas and dust. Light can even echo like sound, illuminating different parts of a dust cloud at different times. These simple physical processes give rise to a great variety and complexity among Hubble images and lead to views of astounding beauty. Masterpiece – This is the best look HDTV can provide at the single largest and best Hubble image ever acquired, the giant mosaic of the Orion Nebula. It’s the nearest star-forming region, a place where stars and planets are being born before our eyes. Two large views elaborate the science within this dazzling image. The first is the Hubble image; the second is a composite with infrared data from the Spitzer space telescope.

Every Hubble image begins in black and white, so why are Hubble’s pictures so colourful? The telescope has a wide range of filters that can be assigned different colours. Sometimes they are assigned to be as close as possible to what the human eye sees and sometimes they are made to look vivid and unnatural to bring out hidden detail. Red and blue stars reveal different temperatures and stages in the life of a star cluster, while different colours in a nebula correspond to different chemical elements. In this segment we show how those vivid hues actually are telling us what the universe is made of. Violent Endings – Not all stars will bow out gracefully, like celestial flowers. The largest stars explode with a terrifying force and briefly shine like beacons across the universe. A supernova’s swift burst of incredible energy forges the entire universe’s supply of precious metals like gold, silver and platinum. Hubble can show us the remnants of these massive explosions in exquisite detail.

Our ancestors thought the sky was flat, but we now know it as a place of infinite depth. Only Hubble can make the jump across those huge distances with stunning clarity. This is an outward-bound journey from “here to infinity” showing all the scales where Hubble operates, from the solar system to the most remote reaches of the cosmos. Etched in Time – Hubble not only looks out into space, it looks back in time. The further light travels to reach the telescope the further back in time we see the object that emitted the light. Solar system objects are seen minutes to hours in the past, and the galaxies millions to billions of years in the past. With the long exposure Ultra Deep Field, Hubble can actually look to the time when the galaxies were still assembling. It’s a violent process that carries on today as massive galaxies collide. These images also foreshadow the fate of our own galaxy, which is even now moving towards an inevitable collision with its nearest neighbour.

The forces of nature, operating at large and small scales create a universe of symmetry and form. Now we consider the interplay of those forces in creating structures as dramatic as Saturn’s rings and the Whirlpool Galaxy, a classic example of a grand design spiral. Stretching the Canvas – The matter we see, both the bright stars and gas and the dark dust, is really just the tip of the iceberg. By watching how galaxies rotate, astronomers realized there must be something else there that is invisible but exerts a powerful gravitational pull. This is dark matter. It has an amazing influence on the universe, forming a “gravitational lens” which distorts our view of distant stars, but also keeping gravity from pulling the universe in on itself. The Hubble Space Telescope not only has allowed us to learn more about dark matter, but about dark energy, the mysterious force that is causing the universe to accelerate outwards. That discovery helped resolve one of science’s great mysteries, the age of the universe.

There are monsters loose in the cosmos, giant black holes that devour matter and spit out high-speed jets of atoms. These monster black holes offer our best chance to study how the laws of physics operate under the most extreme circumstances. The challenge is that these black holes are buried in the hearts of galaxies. Hubble is the best tool we have for peering into these dense regions of space and showing us what’s really going on. In fact, we have our own monster black hole in the Milky Way. Still Life? – Hubble has revealed a universe of stirring beauty, one that seems tailor made to produce creatures that can view and enjoy it. Our understanding of star formation tells us that we are a species created by the stars. We are, in effect, pieces of the universe looking back at itself. The question is: are we the only ones doing this, have the laws of nature brought the right materials together in the right way to make other Earth-like planets, and foster other life and civilizations? This is still an open question, but Hubble is paving the way to our discovery of new planets, and setting the stage for one of the biggest discoveries in astronomy expected in the next generation, namely, the discovery of other planets like Earth.