Stunning is the word, if you can at all describe it! Vista Data Flow System has just mapped the Milky Way Galaxy and has produced a spectacular image of the galactic disk, showing nearly a billion stars. Such is the detail of each region of the mapped galaxy that it is impossible to grasp even when zoomed in. The entire image has been built up from thousands of individual images taken over a decade. The detailing is amazing and it’s not only for the pleasure of the visual organ – the scientific data is also enormous!
Says Dr. Nick Cross from the University of Edinburgh, one of the people involved in the study
There are about one billion stars in there – this is more than has been in any other image produced by surveys. When it was first produced, I played with it for hours; it’s just stunning.
Even hard-nosed scientists, bombarded year-after-year with raw numerical data, have a little child lurking in their somewhere.
The data used in building this image has been taken from UKIDSS/GPS sky survey acquired by the UK Infrared Telescope (UKIRT) in Hawaii and from the Vista telescope in Chile.
Just to help everyone out, there is an online tool, created by Dr Cross and collaborators, which can be used to zoom into smaller and smaller regions of the image. The image itself is a long extended disc of the galaxy and too big to comprehend it at one go!
Do play around with the software. Zoom in and at each level, wait a bit – it takes a few seconds to load fully. It’s well worth the wait! I recommend that you watch it full-screen. Oh, and you might need to bump up the brightness of your monitor a bit.
Scientists are hoping to use this technique for future studies, for mapping starburst galaxies and regions around compact objects. But no matter what, imagination and amazement shall never be lost!
They are firecrackers in the sky and they are massive. The ultra-modern Chandra X-ray Telescope has observed numerous supernovae and copious amount of X-rays in the Carina Nebula. NASA recently released pictures it snapped up using a radio telescope that shows a black hole gobbling up matter in the Centaurus A galaxy. In cosmic terms, both Carina and Centaurus A are close by, but not too close. We are lucky enough to have a great view of the violent and stunning explosions and be awed by them, while coming to no harm. We examine both in this article, and with stunning pictures.
Violent Scene 1:
Location: Carina, a stellar nursery and a violent neighborhood, about 7500 light years from Earth
Protagonist: The Chandra X-ray telescope, the best eye we have to see the X-ray band with
Observation: Streams of X-rays detected, which are signatures of massive supernovae explosions
Let’s get straight to the image.
Get a bigger image here. (And you know you want to… you just have to get a bigger image!)
This is a false color image, because we are actually seeing in X-rays. The red is for low energy X-rays and blue is for the high energy ones. Shades of green and yellow represent intermediate energies.
Here’s what magical about the image: It has been made up of 22 separate images through an exposure time of 1.2 million seconds! It’s ultra-high resolution, and amazingly detailed. We get to see through a lot of dust, that optical radiation just cannot penetrate.
Remember that all the light in the image represents X-rays, which are very energetic. Look at the halo, the diffused purple glow around the central arc. That represents the X-rays being thrown out by ejected materials and charged stellar winds ramming into interstellar matter, and being shocked into X-rays emission. (Here’s the simple rule of thumb from physics: If you have charged particles moving fast and you suddenly stop them, the energy is emitted suddenly as electromagnetic waves, which, in this case, is X-rays. The energy of the EM waves is dependent on how fast the particles were moving and how suddenly they were stopped.)
What’s the big deal? Well, it seems that Carina has been producing very massive stars over the last few millions of years. These stars are so massive that they do not survive too long (Our Sun is a medium sized star and thus it is billed to last for 10 billion years; not so for many giant stars, which can die after living brightly for a short period of 10 million years). These stars die in extravagant explosions, called supernovae, which can outshine an entire galaxy for a few seconds. Further, Chandra has actually managed to count the number of heavy stars (those emitting X-rays) in the neighborhood and it turns out to be greater than previously thought.
We just wanted to show you, as a bonus, what the Carina actually looks like in optical light. It reveals a whole lot more stars, since there are many which don’t emit X-rays.
Location: Centaurus A, a local galaxy in the Centaurus constellation; about 12 million light years away from Earth
Protagonist: The TANAMI project, various radio telescopes
Observation: Radio images reveal giant plumes of radio waves in jets driven by the galactic supermassive black hole
Verdict: Scary and beautiful
The Centaurus A galaxy is an elliptic galaxy (our Milky Way is a spiral galaxy), having a central supermassive black hole. NASA’s radio telescopes, under the TANAMI project, have now glimpsed the very heart of the galaxy and what they see is awe-inspiring. The central black hole throws out matter in jets, as matter from surrounding stars are yanked in by the black hole.
The black hole is estimated to be 55 milliontimes more massive than the Sun. Advanced interferometry techniques enhance the quality of the images. Interestingly, NASA’s Fermi Gamma Ray Space Telescope has detected very high energy in the central parts of Centaurus A. Where these come from is a mystery.
Enjoy the images. Also, there is more information in a nice little video NASA has prepared. Hereit is!
Remember the golden words. The Universe is not queerer than we suppose; it is queerer than we can suppose.
If the Cosmos is the place of all things beautiful and unusual, the Hubble Space telescope (known simply as Hubble’ or HST) is the ultimate eye to see it with. Launched on 20th April, 1990, aboard the Discovery space shuttle by NASA, as the best of the space-based optical telescopes, Hubble has reached out to all.
Hubble’s images have filled the hard disks of active researchers and eager school students alike, and these have endeared the large floating eye in space to millions worldwide. It has captured stunning, but violent galaxy collisions, seen never-before seen nebular formations, glimpsed the merging of galactic black holes and captured the awe-inspiring and data rich alleys of star-forming nurseries, all the while enthralling us and challenging our own perception of the vastness of the universe. In fact, the word Hubble’ today bears more resonance with the telescope rather than the famed astronomer, Edwin Hubble, after whom it is named.
Hubble also happens to be the only telescope that was serviced by astronauts in space. When Hubble started acquiring images, a flaw was found in the positioning of the main mirror. A collective sigh and gasp throughout the astronomy fraternity around the world was followed by a daring and successful mission by NASA technicians, which involved them going into space and correcting the incorrect alignment of the main mirror. Hubble has never looked back since.
Enjoy the brilliant images below (they may take a second to load). Don’t forget to wish a very Happy Birthday to Hubble. To get more, click here.
Astronomers released this brilliant new snap by Hubble in order to celebrate its 21st birthday. (Go to link for a bigger image!)
Hubble is supposed to function till 2014, after which its successor the James Webb Space Telescope is expected to take over.
I expect a few moist eyes when Hubble is finally plunged into the ocean. I know that my eyes will be wet.