Happy birthday HST! (Image credit: NASA/ESA)
That amazing instrument, the Hubble Space Telescope (HST), has just celebrated its twentieth anniversary since it was placed in orbit. Since then, (after a rocky start, remember that dodgy mirror?) it has revolutionised not only what we know about cosmology, star formation, exoplanets and so on, but also how we see the Universe. If you donòÀÙt believe me, look at the pictures in a glossy astronomy book from the 1980s; the cosmos was fuzzier, duller and somehow less three dimensional back then!
To celebrate, the anniversary, NASA, ESA and the Space Telescope Science Institute have issued an especially striking image (above). It is a close-up of part of the Carina Nebula, a huge cloud of gas, mainly hydrogen, and dust some 7500 light years (2400 parsecs) from Earth. The Carina Nebula cannot be seen from EarthòÀÙs northern hemisphere but is a naked eye object in the southern hemisphere. This is a false-colour image coded so that oxygen appears blue, nitrogen and hydrogen as green and sulphur as red. This helps astronomers understand the dynamic processes inside the nebula which is a star-forming region.
The image shows a spectral column of gas molecules and dust, three light years (less than a parsec) tall. This pillar is being sculpted into a phantasmagorical shape by the fierce starlight and winds of particles from its newborn stellar companions and the super-hot hatchling stars within. The Hubble team have named this image òÀØMystic MountainòÀÙ. To me it is an image suggestive of boiling, turbulent motion. On vast time scales the Universe throbs with motion and action. If we could observe the nebula as closely as this for millennia, taking pictures over the years and stringing them together into a movie, I imagine we would see it pulse and writhe like some huge cosmic living creature, eventually vaporising in the onslaught of radiation from the stars it has birthed.
The HST is reaching the end of its planned life, being last serviced by astronauts in May 2009. All being well the HST will be superseded by the much larger James Webb Space Telescope in three years time. I wonder what marvels this gigantic observatory will reveal?
