Look up at the sky and you see stars and galaxies and planets. But way in the background lurks an interesting form of radiation known as the Cosmic Microwave Background. That's the universe's baby picture, and when we study that picture, we don't only see its past — we also see its future.
Next time you pull out your baby pictures, take a look at the details: what you looked like, who you were with, what you were doing. Often, we can "see" a bit of ourselves today by looking at what we used to be long ago. Our parents, friends, and activities all shaped us into the person we became.
This concept not only works for people, but it's also a useful analogy for science. Even our 13.8-billion-year-old universe was a baby in a time long, long ago – just after the universe was formed in an event known as the Big Bang. Shortly after birth, the universe was so hot and so dense that not even light could penetrate the tiny cocoon. Then space expanded rapidly, allowing light to shine through and molecules to come together. The first stars and galaxies turned on, and just after them came the first planets.
Funny enough, we can still see evidence of all that activity by using microwaves. Light is in a spectrum; we can see some of it with our eyes, but there are other forms of light, like X-rays and microwaves, that we can't see except with telescopes or other scientific instruments. Microwaves have extremely long wavelengths, and by using them, we can peer all the way back to the universe's first few thousand years. Scientists call this "baby picture" the Cosmic Microwave Background, or CMB.
Follow @shashastro for more...
#space #universe #cosmos #astrophysics #astroworld #nightphotography #photography #astronomy #astrofacts #science #nasa #galaxy #alien #moon #astronomer #astronauts #hubbletelescope #hubble #deepspace #spacex #nebula #milkyway #cmb