Hubble, who, in the 1920’s, found galaxies beyond the Milky Way and discovered
that the universe is expanding
.
What did Edwin Hubble discover quizlet?
What did Edwin Hubble be the first to identify and what did he discover about galaxies? The first astronomer to
identify other galaxies besides from the Milky Way Galaxy
. By the year 1929, he had estimated the distance from Earth to 46 galaxies.
What did Hubble discover in the 1920s *?
In the 1920s, Hubble was among the first to recognize that there is
a universe of galaxies located beyond the boundaries of our Milky Way
. During the 1920s, Edwin Hubble observed stars that vary in brightness in a patch of light known at the time as the Andromeda nebula.
What observations show that the universe is expanding quizlet?
What evidence do we have that the universe is expanding?
The amount of redshift in the spectra of distant galaxies is proportional to their distances.
What observational evidence leads Hubble to conclude that the universe is expanding quizlet?
Hubble’s brilliant observation was that
the red shift of galaxies was directly proportional to the distance of the galaxy from earth
. That meant that things farther away from Earth were moving away faster. In other words, the universe must be expanding. He announced his finding in 1929.
How did we discover other galaxies?
Hubble
used the P-L relation to find the distance to the Cepheid he was studying in M31, and proved that it was located outside of our own Galaxy. This finally ended the debate on the nature of the spiral nebulae – they were indeed distant galaxies like our Milky Way.
What is the big BNAG theory?
At its simplest, it says the universe as we know it started with an infinitely hot, infinitely dense singularity, then inflated — first at unimaginable speed, and then at a more measurable rate — over the next
13.8 billion years
to the cosmos that we know today.
What did Edwin Hubble discover that led to the formulation of his law?
Hubble’s law is the
theory that the farther the galaxies the farther they move
. What did astronomer Edwin Hubble discover that led to the formation of his law? When he saw galaxies moving through his telescope. You just studied 10 terms!
What did Edwin Hubble discover by observing absorption lines?
American astronomer Edwin Hubble (who the Hubble Space Telescope is named after) was the first to describe the redshift phenomenon and tie it to an expanding universe. His observations, revealed in 1929, showed that
nearly all galaxies he observed are moving away
, NASA said.
Why was the Hubble Space Telescope placed in orbit quizlet?
Why was the Hubble Space Telescope placed in orbit?
To eliminate the distorting effect of the Earth’s atmosphere
. Radio astronomy and optical astronomy each have attractions over the other.
What is inflationary theory quizlet?
What is inflationary theory?
The idea that there was a time during the early universe where the expansion was greater than at any other time in the history of the universe
.
flatness problem
.
Why is dark matter called dark matter?
Dark matter is called dark because
it does not appear to interact with the electromagnetic field
, which means it does not absorb, reflect or emit electromagnetic radiation, and is therefore difficult to detect.
What is the meaning of a closed universe quizlet?
What is the meaning of a “closed” universe?
The universe will someday stop expanding and start to collapse
. If the density of the universe is greater than the critical density this means that. the universe is expanding at a rate less than the escape speed of the universe.
What kind of object do we think lies in the center of the Milky Way galaxy?
At the very centre of the Galaxy lies a remarkable object—
a massive black hole surrounded by an accretion disk of high-temperature gas
. Neither the central object nor any of the material immediately around it can be observed at optical wavelengths because of the thick screen of intervening dust in the Milky Way.
In which order did the events forming our solar system occur quizlet?
In which order did the events forming our solar system occur?
The solar nebula spun faster and faster and flattened into a rotating disk. Most of the gas was pulled toward the center, where it became hot and dense, forming the Sun
. Which statements describe planetesimals?
Why couldn’t atomic nuclei exist when the universe was less than about 2 minutes old quizlet?
Why couldn’t atomic nuclei exist when the universe was less than two minutes?
Photons with high enough energy can break up atomic nuclei so stable nuclei could not be formed until the universe had cooled
. At two minutes protons and neutrons could link to form deuterium (nucleus of a heavy hydrogen atom).
