How many chemical elements are there known to exist in the universe?

Answer 1

It has been suggested that "the total number of stars in the universe is greater than all the grains of sand on all the beaches on Earth."

There may be more stars, as there are likely more than 170 billion galaxies in the observable universe, and there may be considerably more we cannot see.

Galaxies have been observed that have as few as tens of millions of stars and as many as a hundred trillion stars (1 x 1014).

Answer 2

The visible universe is estimated to contain between 1078 and 1080 atoms.

(One estimate at the higher end of the range is 4 x 1079.)

This is the estimated number of atoms in the observableuniverse, but since we do not know the absolute size of the universe, we cannot be certain.

(Most of the matter in the universe is still hydrogen.)

Answer 3

Astronomer Carl Sagan, in his TV series "Cosmos", said "BIL-lions and BIL-lions of galaxies". His exaggerated pronunciation of this phrase attracted a lot of attention, and not a little mockery. In truth, however, Sagan was wrong.

After the launch of the Hubble Space Telescope, and after the Space Shuttle mission that repaired its defective lens, NASA scientists aimed the Hubble toward an entirely blank area of space, and captured a series of photos of what was in that completely empty area of the sky. The resulting images, called the Hubble Deep Field, revealed that in that "empty" spot in the sky, there were thousands of galaxies. Further observations have confirmed that there are not "billions AND billions" of other galaxies; there are "billions OF billions" of other galaxies.

There is no way to come up with even an approximate answer. Whatever number you can come up with, there are probably a hundred times more.

Follow the link below to the Hubble Deep Field image. There are no stars there; EVERYTHING in that photo is another galaxy. The approximate size of the image is a little smaller than a pinhead held at arms length.

answer2:

There are roughly 10 trillion (10x10E12) galaxies

Answer 4

The number of atoms in the observable universe is somewhere in the vicinity of 1080. We can't even really estimate the number of atoms outside the observable universe ... it could be zero, or it could be infinite, and we have no real way of knowing which.

Answer 5

There are perhaps something on the order of 1080 atoms in the observable universe, or at least that is a figure that seems to be tossed around a bit. A link can be found below.

We know that 1 mole of hydrogen is 1 gram, which has 6.022 x 10^23 atoms in it. We can easily approximate 1 kilogram (1000 grams) of any material to 1000 moles, since all atoms are based on the hydrogen model multiplied by X number of times corresponding to their atomic number.

So, for example, although 1 kg of Iron is not 1000 moles, as Hydrogen is, but about 20 moles, one mole of Iron has 26 protons (29 neutrons) and 26 electrons, and has about 26 times the mass of hydrogen. So 1 kg of Iron is about 6.022x10^23 * 20 = 1.2 x 10^24 ~ 10^24 atoms, this is not far from 10^26 hydrogen's atoms. The most common element and atom in the universe is hydrogen anyway. Therefore 1 kg of any material can reasonably be approximated to about 1000 moles, which is about 6.022 x 10^26 atoms, or about 10^26 atoms per kilogram of mass in the universe.

Earth has ~ 6 x 10^24 kg of mass. This is, 6 x 10^24 * 6 x 10^26 (number of atoms in 1 kg of substance) about 3.6 x 10^51 atoms or roughly 10^51 atoms. Now this might seem like very close to 10^80 atoms, but it is not. It would take approximately 10^30 Earths to reach that number, which is far more than our Galaxy has in mass.

Our Galaxy has 1.4 x 10^42 kg of mass, which is about 10^45 moles. Multiplying that times Avogado's number (6.022 x 10^23, or about 10^23) we get 10^68 atoms in the Milky Way. There are 125 billion galaxies in the observable universe, which is 1.25 x 10^11, which is approximately 10^11 galaxies. From that:

10^68 * 10^11 we get 10^79, or about 10^80 atoms (10^78 if we count atoms as heavy as Iron, above which the universe does not naturally make on any grand scale; it goes up to Uranium, which is about 5 moles/kg) in the observable universe, with about as many electrons (1 hydrogen atom as per our model has 1 proton and 1 electron).

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A second way is to use the known length of the observable universe. The observable universe is about 93 billion light years. Taking the volume of the universe as a sphere: 4/3*pi*R^3, the volume of the universe would be:

(4/3)*3.141592*46.5^3 = ~ 4.2 x 10^23 cubic lightyears as the volume of the observable universe.

Knowing that the universe is about 0.0000000000000000000042 percent matter, multiplying 4.2 x 10^23 by that gives us ~ 1.77 cubic lightyears of matter.

1 lightyear is 10 trillion kilometers, which is 1 million trillion centimeters or 10^18 cm in 1 lightyear. 1 cubic lightyear would then be (10^18)*(10^18)*(10^18)=10^54 cubic centimeters in 1 cubic lightyear so about 1.77x10^54 cubic cm of matter in the universe. It's estimated that there are about 10^17 atoms in an average cubic centimeter, so 1.77x10^54 * 10^17 = 1.77 x 10^81 which is about 10^81 atoms in the universe

Answer 6

We're aware of 91 chemical elements which appear to exist "in nature", although it's certain that many of the artificially-created elements have been created naturally before in supernova explosions. It's just that they appear to have such short half-lives that they undergo radioactive decay fairly quickly.

The heaviest "natural" element is Uranium, at Atomic Mass 92. One fairly light element, Technetium at atomic number 43, has no stable isotopes and has never been found in nature. The name of the element depicts its "technical" origin.

Answer 7

(Most of the matter in the universe is still hydrogen.)

Answer 8

To date, the number of people in the Universe is the same as the number of people on Earth.

This could change at any moment.

See related question.

Answer 9

Countless ones. Scientists aren't exactly sure. They don't have the technology to explore out that far, yet.

Answer 10

Most astronomers estimate the number at somewhere between 1070 and 1090.