The Hubble Space Telescope has created some amazing pictures of the cosmos during its 25 years in orbit, but that’s not the only thing the telescope has accomplished. Information gathered by the long-serving telescope has changed the way we understand the universe
Studying the cosmos for over a quarter-century, the Hubble Space Telescope has made more than a million observations and changed our fundamental understanding of the universe. Still at the peak of its investigative capabilities and in high demand from astronomers worldwide, Hubble remains one of the most productive scientific instruments ever built.
1. Estimating the age of the Universe
One of Hubble’s main tasks was to figure out the age and size of the universe. Researchers now know that the universe is about 13.7 billion-years-old thanks to research performed using Hubble’s data.
“Knowing the age of the universe isn’t just a matter of curiosity,” Hubble scientists said in a statement. “By giving us a time scale for the development of stars and galaxies, it helps us refine our models of how the universe — and everything in it — formed.”
2. Understanding seasons on other planets
Scientists using Hubble have also been able to track seasonal changes on planets. Hubble tracked Jupiter’s weather, for example, allowing researchers to see color changes in bands of clouds in the huge gas giant’s atmosphere.
Hubble also gave people on the ground an amazing view of a comet impacting another planetary body when Comet Shoemaker-Levy 9 crashed into Jupiter in 1994.
3. Seeing galaxies in the early universe
In 1995, mission controllers directed Hubble to take a series of images looking at one small spot in the sky, and the results were astonishing.
The image created from that series of exposures revealed thousands of galaxies and quickly became one of Hubble’s most iconic views of the universe, called the telescope’s first deep field. The Hubble continued to take images of the deep universe through the course of its lifetime after multiple servicing missions by astronauts replaced cameras on the telescope.
“A series of deep fields taken with Hubble over the past 20 years — with each generation of Hubble’s cameras — has allowed astronomers to probe the star formation history of the universe over 95% of its lifetime,” Hubble astronomer Jennifer Lotz said during a press conference Monday.
4. Supermassive black holes
But by measuring the speed of material that surrounds a black-hole, it is possible to calculate its mass using the laws of gravity. If there is more mass than is accounted for by the stars we see, the rest could be due to a black hole. Soon after its launch, Hubble confirmed earlier SMBH (supermassive black hole) detections by taking images five times sharper than those obtained from the ground. The Hubble Space Telescope became known as a ‘black hole hunter’, due to its ability to measure the speed of surrounding gas and stars.
5. Dark matter
The galaxies, stars and planets that we can see make up just 15 per cent of the Universe’s matter. The rest – the other 85 per cent – is dark matter and it neither emits nor absorbs any known wavelength of light. To construct it, half a million galaxies were observed by the Hubble Space Telescope. The dark matter bends the light in a ‘gravitational lensing’ effect, making the galaxies appear distorted. By observing this, it’s possible to deduce where dark matter lies.
6. Accelerating expansion of the universe
Not only is the expansion of the Universe accelerating, but it is also being fuelled by ‘dark energy’. In 1998, astronomers released new data on how the brightness of supernovae changed over time. It showed that the light coming from the most distant exploding stars was fainter and more stretched (red-shifted) than predicted. It meant that they were further away than astronomers calculated – a result that didn’t fit with the existing idea that the tug of gravity was causing the expansion of the Universe to slow down. For the team leading the project, this could mean only one thing: the expansion rate is not slowing at all. It’s speeding up.
7. Alien worlds
Most of the more than 400 or so extrasolar planets found so far were actually discovered by telescopes on the ground. Still, Hubble has made some important advances in our research into alien worlds, such as determining the composition of the atmosphere of an exoplanet for the first time and actually imaging the visible light of Fomalhaut b.
8. Quasars and active galaxies
Before Hubble, quasars were considered to be isolated star-like objects of a mysterious nature. Hubble has observed several quasars and found that they all reside at galactic centres. Today most scientists believe that supermassive black holes at the galactic centres are the “engines” that power the quasars. They also believe that quasars, radio galaxies and the centres of so-called active galaxies just are different views of more or less the same phenomenon: a black hole with energetic jets beaming out from two sides.
9. Composition of the Universe
How Hubble studied what the
Universe is made of, and came to some startling conclusions.
All over the Universe stars work as giant reprocessing plants
taking light chemical elements and transforming them into heavier ones. The
original, primordial, composition of the Universe is studied in such fine
detail because it is one of the keys to our understanding of processes in the
very early Universe.
10. 2014’s Mangalyaan or MOM
The Hubble telescope has discovered 5 moons orbiting Pluto namely, Charon, Hydra, Kerberos, Nix and Stynx. Besides just discovering these moons, Hubble has revealed many more startling facts like Nix and Hydra, are in a chaotic rotation. This means that an observer on these two moons Pluto would not see the same face of the moons from one night to the next. For visitors on the moons themselves, things would get even more confusing, as every day would be a different length to the one that preceded it.
