Tag Archives: our dynamic universe

Hubble discovers our universe is expanding⤴

from @ fizzics

In the 1920s, Edwin Hubble had access to the Hooker telescope on Mount Wilson, Los Angeles.  This was the largest telescope in the world at that time.  His first breakthrough was the discovery of a cepheid variable star in the Andromeda nebula.  This enabled him to calculate the distance to Andromeda and he quickly realised this was ... Read more

redshift⤴

from @ fizzics

more redshift   and Yoker Uni’s video about Doppler and stuff   While redshift can be used to tell us about the recession velocity of (non relativistic) galaxies, we also need to find a way to measure the distance to these galaxies.  Astronomers have two main methods to measure these distances; parallax (more parallax here) and cepheid ... Read more

special relativity⤴

from @ fizzics

Special relativity is tricky get get your head round.  Let’s start with a video about the speed of light. This video follows Einstein’s thought process as he worked through his special theory of relativity. special relativity from mr mackenzie on Vimeo. time dilation A Tale of Two Twins from Oliver Luo on Vimeo. another take on ... Read more

revision notes for higher ODU resit⤴

from @ fizzics

I’ve attached a set of notes to help with your revision for the Our Dynamic Universe resit on Tuesday.  Remember that the resit paper will have knowledge questions only, so focus on the unit content during your revision rather than practising numerical problems. Thanks to Mr Noble for sharing his ODU notes.

cosmic microwave background radiation⤴

from @ fizzics

The cosmic microwave background radiation (CMB) is radiation left over from the big bang.  When the universe was very young, just as space became transparent to light, electromagnetic energy would have propagated through space at a much shorter wavelength.  Nowadays, the temperature of space has fallen to approximately 2.7 K (that’s 2.7 K above absolute zero!) ... Read more

star colours⤴

from @ fizzics

Astronomers often refer to the colour of a star, which seems a bit odd because we mostly see stars as white twinkly objects.  However, even with the naked eye, we can look closely at certain stars and detect a hint of colour – just look at this image of the Orion constellation.  As we view ... Read more