Majors

first black hole photo 📸

in 2017, a decade of work at the EHT (event horizon telescope) finally paid off when they were able to take a photo of a real black hole. the EHT is a combination of eight telescopes spread worldwide, which were all used to piece together images of black holes - sort of like an earth sized telescope!

galileo galilei postulated that in EVERY inertial reference frame, the laws of motion held up.

variable stars are stars whose visibility and brightness as seen from earth varies over time.

black holes will only form from stars that are massive enough - as in mass, not size.

small stars expand into red giants at the end of their life, and then they puff out their edges and they become a white dwarf (which are also pretty dense).

large stars, however, expand into red SUPERgiants, and terminate their life via a cataclysmic, bright supernova. the remnants of the supernova can form nebulae, and super dense celestial objects known as neutron stars. but they can also form something else, something much more ominous; a black hole.

the colour of a star actually depends on its temperature, due to something known as black body radiation. a perfect 'black body' absorbs all radiation and is the best emitter.

hotter objects emit electromagnetic waves with shorter wavelengths, and slightly colder objects emit longer wavelengths (which could be seen as a bit counterintuitive).