Cosmic thoughts
It makes our world seem small, when you consider the vastness of the cosmic universe.
Last week, the world's most powerful space telescope unveiled its first images and they are mesmerizing. For a person standing on Earth looking up, these images are approximately the size of a grain of sand held at arm’s length. This deep field uses a lensing galaxy cluster to find some of the most distant galaxies ever detected.
Southern Ring Nebula, courtesy NASA Webb Space Telescope.
For example, the planetary nebula shown above is an expanding cloud of gas that surrounds a dying star, approximately 2,000 light years away. Webb’s powerful infrared eyes bring a second dying star into full view for the first time. From birth to death as a planetary nebula, Webb can explore the expelling shells of dust and gas of aging stars that may one day become a new star or planet.
Amazing!
When I used to gaze at the moon as a kid, I always felt it astounding that no matter where people were on the planet we are all gazing up at the same moon. When you think of it like that, it sure makes the world we know as Earth seem pretty small.
With stars it’s a little different. At any point on Earth at any given time, about half of the entire possible sky is visible to us. Basically, we can think of the sky above us as a giant “dome” which is equal to half of the entire sphere around the Earth.
The next time the night skies are clear, lay on the grass and take it all in. It’s a very real possibility that someone somewhere in another galaxy might be looking back 🔭
Images: A large galaxy cluster known as SMACS 0723 showing thousands of galaxies of all shapes, sizes and ages that correspond to different wavelengths of infrared light, by NASA Webb Space Telescope; stars and northern lights in the Keweenaw, by George C. Bailey.