Exam 2 ASTRO

Each element in the periodic table has a unique..

Emission spectrum

if light coming from a stellar object is blue shifted, that means the object is…

towards us

out of all the visible matter (baryonic matter), about what percentage of helium is there in the universe?

24%

which unit of distance is longer?

1) 5,000,000 meters

2) 300,000 AU

3) 6 light years

4) 2 parsecs

2 parsecs

Let’s talk about redshift. If we have an absorption line here on earth at 300 nm, but that same absorption line is seen at 500 nm coming from an object in space, is the object moving towards us or away from us?

moving away from us

If you see a spectrum with dark lines on it, what name does this spectrum have?

absorption spectrum

what particles make up protons and neutrons?

quarks

how much dark energy is there in the universe?

75%

talking about exoplanets, what does the distance between 2 dips tell us?

their orbital period

the expansion and contraction of a Cepheid variable (pulsating star) has a direct correlation to its?

luminosity

At the end of which era of the universe did we first start having matter (sub atomic matter)?

GUT Era

What era do we currently live in?

era of galaxies (Stelliferous Era)

From our perspective on earth, which object seems to be receding (moving away) the fastest from us?

a galaxy 1 million light years from us

which method first gave us understanding that there are other galaxies outside our own?

standard candle method