Two major scientific discoveries provide strong support for the Big Bang theory: •
Hubble’s discovery in the 1920s of a relationship between a galaxy’s distance from Earth and its speed
; and • the discovery in the 1960s of cosmic microwave background radiation.
What evidence supports the Big Bang theory quizlet?
Some pieces of evidence used to prove the big bang theory are
moving galaxies, cosmic background, and the age of the universe
. The main three types of galaxies are spiral, which bullets in the middle with arms that Kirby out words.
What are 3 pieces of evidence for the Big Bang?
Three key pieces of observational evidence lend support to the Big Bang theory:
the measured abundances of elements, the observed expansion of space, and the discovery of the cosmic microwave background (CMB)
. The CMB refers to the uniform distribution of radiation that pervades the entire universe.
What did Hubble’s law prove?
In his short paper, Hubble presented the observational evidence for one of science’s greatest discoveries—the expanding universe. Hubble showed that
galaxies are receding away from us with a velocity that is proportional to their distance from us
: more distant galaxies recede faster than nearby galaxies.
Why is Hubble’s Constant not constant?
In the standard cosmological picture, the
expansion rate
of the universe is constantly changing as the cosmos evolves, but the Hubble constant is a fixed number – it’s the expansion rate of the universe right now.
Why is Hubble’s law important?
Because the exact value of the Hubble constant, H, is so important in extragalactic astronomy and cosmology – it leads to
an estimate of the age of the universe
, helps test theories of Dark Matter and Dark Energy, and much more – a great deal of effort has gone into working it out. …
Is Hubble’s Law accurate?
If the theory is not correct, the distances determined in this way are all nonsense. Most astronomers believe that Hubble’s Law does, however,
hold true for a large range of distances in the universe
. It should be noted that, on very large scales, Einstein’s theory predicts departures from a strictly linear Hubble law.
Is Hubble constant constant in time?
But the “Hubble constant” itself is a misnomer. It has a value today that’s the same everywhere in the Universe, making it a constant in space, but
it’s not a constant in time
.
Is Hubble’s constant decreasing?
If the universe is decelerating,
the Hubble constant is decreasing
. … The velocity of individual galaxies is increasing, but it takes longer and longer for the universe to double in size. Said yet another way: Hubble’s Law relates the velocity v of a galaxy to its distance d via v = H d.
Why can’t a closed universe have a center?
Why can’t a closed universe have a center? A.
It is infinite
. … We think that much of the matter and energy in the universe is “dark.” A.
What are the limitations of Hubble’s law?
Limitations of Hubble’s Law
By using Hubble’s equation,
it is possible to determine a galaxy’s distance from us, once we have measured its velocity of recession
. This is calculated by determining by how much the observed light has been shifted into the red part of the spectrum.
Where is the center of the universe?
There is no centre of the universe
! According to the standard theories of cosmology, the universe started with a “Big Bang” about 14 thousand million years ago and has been expanding ever since. Yet there is no centre to the expansion; it is the same everywhere.
Who created Hubble’s Law?
Edwin Hubble
sought to find a relationship between their distance from us and their speed. He plotted recessional velocity determined by the doppler shift of stellar spectra as a function distance and established what is now know as Hubble’s Law.
Why does Hubble’s law not work all that well for galaxies very close to the Milky Way?
Hubble’s Law
only works for distant galaxies
. … For nearby galaxies, though, their peculiar velocity is larger than their velocity from the expansion, so their peculiar velocity dominates their total velocity, causing them to lie far from the line relating velocity to distance.
What does Hubble’s constant in the equation V Ho D mean?
Hubble’s Law – One of the most important formulas of the 20th century. It shows
the expansion of the Universe by
showing how distant galaxies are moving away from us. Formula: v = H
o
d where: … H
o
= Hubble Constant, measured in km/s/Mpc. d = distance of a galaxy, in Mpc (mega-parsecs)
What is a red shifted galaxy?
Ever since 1929, when Edwin Hubble discovered that the Universe is expanding, we have known that most other galaxies are moving away from us.
Light from these galaxies is shifted to longer
(and this means redder) wavelengths – in other words, it is ‘red-shifted’.
