“When we observed the universe only with optical light, we thought all was serene. When we began observing with radio waves, we learned that there are events in our universe that are violently explosive beyond imagining. Being able to detect gravitational waves will let us observe the universe in a new way again … and we can’t predict what marvels might unfold.“~earthsky.org
Galaxies hidden by Milky Way revealed
For the first time, astronomers peered through stars and dust in the Milky Way galaxy to find … more galaxies. The work helps explain a mystery Great Attractor. (This Mystery is NOT to be avoided!!~L)
Artist’s impression of galaxies found in the ‘Zone of Avoidance’ behind our Milky Way galaxy. The artist created this scene using the actual positional data of newly studied hidden galaxies and randomly populating the region with galaxies of different sizes, types and colours. Image via the International Centre for Radio Astronomy Research (ICRAR), in Australia.
You know how, on a dark night, you can sometimes see the edgewise view of our own Milky Way galaxy? This lovely starlit trail is wonderful to see, and astronomers love to study what’s inside it, but our galaxy is so crowded with stars and dust (Remember the three grains of sand and the cathedral?~L) that they can’t see through it at optical wavelengths. And thus, since the 1800s, astronomers have spoken of some 20% of the sky as a Zone of Avoidance. It’s the region of sky located in the direction of our galaxy’s flat plane. This week, astronomers said, for the first time they’ve been able to use a radio telescope peer through the galactic plane and view hundreds of formerly hidden galaxies. Thus they’ve shed light on a mysterious gravitational tugging from what they had dubbed simply the Great Attractor. These researchers published their work in the Astronomical Journal on February 9, 2016.
In other words, since the 1970s and 1980s, we’ve known there was some Great Attractor in this region – some diffuse, hidden concentration of mass 250 million light-years away – pulling our Milky Way galaxy and hundreds of thousands of other galaxies towards it. We knew the Great Attractor has a gravitational force equivalent to some million billion suns.
Now we now there are some 883 galaxies, at least, in this region of space. A third of these galaxies had never been seen prior to this study.~earthsky.org
(If you don’t subscribe to the newsletter, it might be time. You’re getting less than 1% of it through me and I have a bias, possibly.~L)
And just like that, in a single day, your universe got 883 times bigger. Tell me that’s not a good day. Not even noon yet. Better buckle up and hang on, Hannah!
Here we go!