Table of Contents
- 1 What happened when the universe was about 380000 years old that allowed light to escape and move freely throughout the universe?
- 2 How long would it take for light to reach the most distant object in the universe?
- 3 Why did the universe become transparent to light after 380000 years?
- 4 Who first calculated the age of the universe?
- 5 What happens when dust and gas collide around a star?
- 6 What is cosmic dust and why does it matter?
What happened when the universe was about 380000 years old that allowed light to escape and move freely throughout the universe?
The Universe is uneven, and so are the stars and galaxies and clumps of matter that form within it. The Universe became transparent to the light left over from the Big Bang when it was roughly 380,000 years old, and remained transparent to long-wavelength light thereafter.
How long would it take for light to reach the most distant object in the universe?
Travel Time At the rate of 17.3 km/sec (the rate Voyager is traveling away from the Sun), it would take around 225,000,000,000,000 years to reach this distance. At the speed of light, it would take 13 billion years!
How can you estimate the age of the universe using the Hubble constant?
But, from Hubble’s Law, we know that v=H0D . So, t=D/v=D/(H0×D)=1/H0 . So, you can take 1/H0 as an estimate for the age of the Universe.
How was cosmic microwave background radiation discovered?
But the CMB was first found by accident. In 1965, two researchers with Bell Telephone Laboratories (Arno Penzias and Robert Wilson) were creating a radio receiver, and were puzzled by the noise it was picking up. Dicke’s team got wind of the Bell experiment and realized the CMB had been found.
Why did the universe become transparent to light after 380000 years?
After the recombination of the two particles, the photons could move freely, later to become the CMBR. We can read here: The Universe became transparent to the light leftover from the Big Bang when it was roughly 380,000 years old, and remained transparent to long-wavelength light thereafter.
Who first calculated the age of the universe?
Planck
In 2013, Planck measured the age of the universe at 13.82 billion years.
What was used to prove that the universe is expanding?
History. In 1912, Vesto Slipher discovered that light from remote galaxies was redshifted, which was later interpreted as galaxies receding from the Earth. In 1922, Alexander Friedmann used Einstein field equations to provide theoretical evidence that the universe is expanding.
How much of the universe is Dusty?
Despite all the research on dust, it is only a small fraction of the universe. Even in moderately dusty galaxies like our own, dust accounts for less than 1\% of the mass. Yet its ability to transform the light passing through it completely changes the way we see the universe.
What happens when dust and gas collide around a star?
Some of the remaining dust and gas begins to spin around the star and flatten into a disk. Specks of dust collide, and as their gravity increases, they pull more dust and gas onto their surface, accreting material. Over time, they become pebbles, then boulders and, sometimes, a few million years later, planets.
What is cosmic dust and why does it matter?
Cosmic dust, which collects in galaxies in loose fogs or thick clouds, has often plagued astronomers. The tiny grains, each 10,000 times smaller than the eye of a needle, absorb light, scatter it, or change its wavelength so it’s invisible to the eye. In doing so, dust steals some of the few clues we have to understand the nature of the universe.
What is the relationship between gas and dust in space?
Gas and dust are generally intermixed in space, although the proportions are not exactly the same everywhere. The presence of dust is apparent in many photographs of emission nebulae in the constellation of Sagittarius, where we see an H II region surrounded by a blue reflection nebula.