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hello! i've got some GROUNDBREAKING space news for you!

scientists have uncovered evidence for a gravitational wave background (GWB) in our universe, and the way they went about it is fascinating.

To fully understand what's going on here, we need to go into a bit of background information.

First of all: what are gravitational waves? gravitational waves are often called 'ripples' in spacetime, often caused by extremely energetic processes such as black holes colliding, or two neutron stars orbiting each other closely.

So, how did scientists figure this out? They used 67 pulsars (known as the Pulsar Timing Array) throughout the Milky Way, practically creating a galaxy-sized telescope in order to study this.

Pulsars are the extremely dense cores of massive stars, left over after they go supernova. These are fascinating on their own, but for this project, they had an essential feature: Pulsars rapidly rotate (think up to hundreds of rotations per second), spewing radiation out in pulses from their magnetic poles. For some pulsars, these radiation jets cross Earth's line of sight, and we get incredibly constant bursts of radio signals, which can be catalogued and used as a sort of standard, universal clock.

Here is a link to a gif showing the rotation of a pulsar. Please be warned for flashing and eyestrain.

For 15 years, a team of astronomers working for the North American Nanohertz Observatory for Gravitational Waves (NANOGrav), used radio telescopes around the globe to track minuscule changes in the signal patterns from pulsars. The changes they found are due to the slight movement of spacetime between us and the pulsars, stretching and compressing the paths of their radio waves as extremely low frequency gravitational waves pass through the universe (yes, that includes you. your atoms, as well as the atoms making up everything around you, are very slowly shifting position, dancing along to the heartbeat of the universe).

At the moment, scientists are still debating what could have caused this gravitational wave background, but some there are some leading theories: the GWB could be caused by trillions of binary black hole systems (black holes orbiting each other) throughout the universe. It could also be due to cosmic inflation, or even the big bang itself. Scientists just don't know yet, but the opportunities this discovery opens up are incredible.

The knowledge of the GWB could help us better understand the formation of early galaxies, or even help us understand the origin of the universe.

If you’re a Non-Muslim and you see a Muslim praying in public, could you please not pass in front of them?

Go behind them, but not in front. 👍

[REDACTED] if you agree

Is it just me or is anyone else terribly, horribly, mixed with both a love for science yet love for the arts. I love music and I love studying new things, I want to play piano and read poetry but I am also filled with the longing to learn biology, physics, math, chemistry and so much much more. My heart and mind both ache to do everything but I don’t know how to or even if I can. I’m just stuck jumping back and forth between the two.

PHYSICS APPRECIATION: CHERENKOV RADIATION

I'm a student, enthusiast and massive nerd, this is my best attempt at sharing all the awesome little secrets and tid bits, beyond your average high school science class. (It's cool I swear).

In a visit to Sizewell power station last year (highly reccomend), I learned that nuclear reactors don't glow the radioactive green we see in cartoons:

But rather a brilliant blue:

It's cause is simmilar to that of a sonic boom. Normally, matter can't accelerate past the speed of light, however, the speed of light in water, is much slower than the speed of light in a vacuum (around 75%). This means that, charged particles emitted during nuclear reactions, are able to exceed the speed of light in their medium (water), and things get weird.

Water is dielectric (able to be electrically polarised), so when charged paricles faster than the speed of light travel through it, its particles become polarised. In order to return to their ground state, the particles emit photons.

The photos travel as waves with high frequencies and short wavelengths (remember ROYGBIV?), which tend towards the blue/violet end of the visible light spectrum, hence the blue. (And perhaps even ultraviolet, which we can't see).

If anyone wants me to go more in depth, or if I've made any mistakes, please lmk!!