What was the first matter in the universe?
As the universe continued to expand and cool, things began to happen more slowly. It took 380,000 years for electrons to be trapped in orbits around nuclei, forming the first atoms. These were mainly helium and hydrogen, which are still by far the most abundant elements in the universe.
What is the evidence that the universe was very uniform during its first 400 000 years?
What is the evidence that the universe was very uniform during its first 400,000? It was too hot for atoms to form so everything was just an opaque sea of subatomic particles.
What does it mean that for the first 30000 years of its existence the universe was radiation dominated?
First 30,000 years. universe was radiation dominated. photons prevented matter from forming clumps. Then it was matter dominated where super clusters and smaller clumps of matter formed. Today it’s dark energy dominated.
What is the oldest light in the universe?
Bottom line: New observations of the oldest light in the universe indicate that the cosmos is 13.77 billion years old, and help resolve inconsistencies with other previous estimates.
How long was the universe dominated by radiation?
Radiation-dominated era After Inflation, and until about 47,000 years after the Big Bang, the dynamics of the early universe were set by radiation (referring generally to the constituents of the universe which moved relativistically, principally photons and neutrinos).
How many times has Universe existed?
Our universe has existed for nearly 14 billion years, and as far as most people are concerned, the universe should continue to exist for billions of years more.
Will universe last forever?
Theories about the end of the universe. The fate of the universe is determined by its density. The preponderance of evidence to date, based on measurements of the rate of expansion and the mass density, favors a universe that will continue to expand indefinitely, resulting in the “Big Freeze” scenario below.
Does the universe have an end?
Expansion forever. The expansion starts off fast, and there isn’t enough matter and energy to overcome that initial expansion. The expansion rate drops but never reaches zero; the Universe expands forever and ends in a Big Freeze.
Does space have an end?
No, they don’t believe there’s an end to space. However, we can only see a certain volume of all that’s out there. Since the universe is 13.8 billion years old, light from a galaxy more than 13.8 billion light-years away hasn’t had time to reach us yet, so we have no way of knowing such a galaxy exists.
What would happen if you kept going up in space?
Your spacecraft would be much heavier, and much larger than this one, and you would still be limited in fuel, oxygen, water, and food. You would have to plan to return to the Earth before you left the launch pad.
How does astronauts poop in space?
Today, astronauts at the International Space Station go to the bathroom into a little plate-sized toilet hole, and a fan vacuum sucks their excrement away and a separate funnel equipped with a fan suction their pee away.
Does space have a smell?
As it turns out, space actually does have a distinct odor. Astronauts returning from space claim that their suits smell, in a word, burnt. The lingering scent of space is “acrid” and “metallic,” reminding the astronauts of charred meat or welding fumes.
Is an hour in space 7 years on earth?
No. The time-dilation effect of Einstein’s relativity has nothing to do with space. The faster you’re moving, the slower time goes for you. So if you were on some planet moving extremely fast through space, like in the movie Interstellar, then you could miss 7 years on Earth every hour.
Do female astronauts wear bras in space?
According to this Salon article, yes they do. They don’t need the support, but the bra keeps their wobbly bits in place while floating around in microgravity. They also like having an extra layer between said bits and the cameras all over the space station.
Do astronauts shower?
The astronauts wipe their body clean by using a wet towel, and wash their hair by using waterless shampoo. Since water does not flow in a zero-gravity environment, the astronauts cannot wash their hands under a faucet as you do on Earth. So, there are no sinks or showers inside the space shuttle.
Why is space silent?
In space, no one can hear you scream. This is because there is no air in space – it is a vacuum. Sound waves cannot travel through a vacuum. ‘Outer space’ begins about 100 km above the Earth, where the shell of air around our planet disappears.
Why we Cannot talk in space?
Because there is nothing out in space (like an atmosphere), the sound waves from one astronaut’s whistling can’t travel over to the other astronaut’s ears. That’s why the astronauts use radios to communicate—even if they’re floating in space right next to each other!
Where is the quietest place on Earth?
Is there air on the moon?
Based on lunar rock samples returned to Earth during the Apollo missions, scientists know that the moon’s soil, or regolith, contains about 40 to 45 percent oxygen by weight. This makes oxygen the most abundant element on the moon’s surface. But harvesting it is difficult.
Does Moon have wind?
Doubters say there wouldn’t be wind on the Moon as there is no air. The truth to this is that although it looks like it is moving, it isn’t. When it was stuck in the ground it would have been disturbed and kept that bent shape. In videos, it also appears to wave back and forth.