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What is a Parsec? 539 Views


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Description:

We’re pretty sure that a parsec is the amount of time it takes a golfer to make par, but just in case we’re wrong, let’s check out this video.


Transcript

00:00

Thank you We speak What on earth is a par

00:06

sec A watchman Okay so you're in the kitchen Mom

00:10

ask you to pass her the par sec Well chances

00:12

are she meant to ask for the parsley It would

00:16

be a little hard to hand her a parsecs since

00:17

it's nothing more than a unit of measurement And he

00:20

couldn't exactly set an egg timer to measure one either

00:22

because despite its misleading name ah par sec is not

00:26

a measure of time but a measure of distance Well

00:30

how much distance Well considering we're talking in terms of

00:33

space you can bet it's going to be more than

00:35

on say three or four feet like a light year

00:39

As you may know especially if you've ever time to

00:41

stop Watch light travels at one hundred eighty six thousand

00:44

miles second and there are thirty one million five hundred

00:49

thirty six thousand seconds in a year On a second

00:53

year a light year is the distance light can travel

00:57

in one year so one hundred eighty six thousand times

01:01

thirty one million five hundred six thousand gives us almost

01:03

six trillion miles in a light year Trillian sixteen Yeah

01:13

a par sec is three point two six light years

01:17

for nineteen point two trillion miles a long way But

01:22

why do we need a unit of measurement that seems

01:24

so random aren't lightyears and miles enough Do we really

01:28

need to throw another unit into the next round Like

01:31

all things science there's actually a pretty sensible reason for

01:33

us to use parsecs when calculating interstellar distance well years

01:37

ago Many years ago astronomers and gaze at a star

01:42

from one end of the earth orbit and then they

01:44

see that same star Six months later when earth was

01:47

on the opposite side of its orbit well they realized

01:51

they could get a baseline for a parallax measurement That

01:59

was twice the earth distance to the sun but using

02:03

tried and true measuring methods the numbers and get a

02:05

tad too unwieldy So they pulled the idea of a

02:09

parsecs out of their brains Brains brains where g rated

02:15

insurance the particles the distance at which a star would

02:19

show a one degree arc Wrong Yeah one degree arc

02:25

Second shift if viewed across a baseline of one astronomical

02:28

unit Aii the radius of the earth orbit I got

02:31

this diagram Here's us here's the sun here's the sun

02:36

on weight distance from us to the sun that's one

02:41

You are one astronomical unit So you were on the

02:47

earth and we look at a star located here a

02:50

parallax angle measuring one mark Second is formed See that

02:56

distance from our son too That star yeah one parsecs

02:59

unfortunately it's a little tough to look at a star

03:01

that fits these parameters because well there aren't any No

03:04

stars are even that close thinking really oh snap and

03:10

an arc second is over tiny so parsons won't really

03:14

have too much use to us until telescope for development

03:18

That could make sense of that type of very precise

03:20

information But now that the technology is available it's a

03:26

cinch to measure distances between our son and all the

03:29

other stars out there The next time your mom ask

03:34

you to hand her the part sack while you could

03:35

tell her to go Take a long trip into space 00:03:38.038 --> [endTime] And it won't even be an insult

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