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How massive is the universe?

Answer 1

It's hard to say, but it's really really big.

If you mean the universe as in everything around us, including outside of our galaxy, then its unknown. The universe is ever-expanding and growing, so we will never have an exact measurement.

Currently our 'observable universe' is 28 billion light-years in diameter . When you calculate that to kilometers, well you get a really really big number.

One Astronomical Unit, or AU for short, is 150 million km. And in a single light year there is 63241.1 AU. And we have 28 billion light-years in diameter that we can see.

So! Here is the math!

63241.1AU x 28,000,000,000ly = 1,770,750,800,000,000AU

1,770,750,800,000,000AU x 150,000,000km = 2.6561262e+23

So our current observable universe is 2.6561262e+23km.

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Answer 2

Luca de

The mass of the universe is estimated to be around 3 x 10^52 kilograms.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.