Light-time - Revision history

RichardWSmith: Added how far Mars is from the sun in light minutes.

2024-10-26T20:54:01Z

Added how far Mars is from the sun in light minutes.

RichardWSmith: /* Common units of light-time */ fixed exponent error, was using km not meters.

2024-10-26T20:51:55Z

Common units of light-time: fixed exponent error, was using km not meters.

RichardWSmith: /* Common units of light-time */ fixed typo

2024-10-26T20:50:44Z

Common units of light-time: fixed typo

RichardWSmith: Gave example, fixed columns.

2024-10-26T20:50:09Z

Gave example, fixed columns.

RichardWSmith: /* Common units of light-time */ Added light hour

2024-10-26T20:48:19Z

Common units of light-time: Added light hour

Michel Lamontagne: /* Common units of light-time */

2020-10-27T15:18:02Z

Common units of light-time

Michel Lamontagne at 15:10, 27 October 2020

2020-10-27T15:10:01Z

CZMatt: /* Common units of light-time */

2019-12-07T06:26:59Z

Common units of light-time

CZMatt at 06:23, 7 December 2019

2019-12-07T06:23:09Z

CZMatt: Created page with " '''Light-time''' is the product of the speed of light in a vacuum and time it takes light to travel a certain distance in space. It is most commonly used in light-years t..."

2019-12-07T06:22:49Z

Created page with " '''Light-time''' is the product of the speed of light in a vacuum and time it takes light to travel a certain distance in space. It is most commonly used in light-years t..."

New page

'''Light-time''' is the product of the [[speed of light]] in a vacuum and time it takes light to travel a certain distance in space. It is most commonly used in light-years to calculate interstellar distances.<ref>[https://www.merriam-webster.com/dictionary/light-time “Light-Time.”] n.d. In ''Marriam-Webster Dictionary''.</ref>

== Common units of light time ==
The light-second, light-minute, and light-year are the most common light-time units used.
{| class="wikitable"
|+Common units of light time
!Unit
!Meters
!Miles
![[Astronomical Unit|Astronomical Units]]
|-
|1 Light-second
|<math>2.9979\times10^{8}\mathsf{m}</math>
|<math>1.8628\times10^{5}\mathsf{mi}</math>
|0.0020 AU
|-
|1 Light-minute
|<math>1.7987\times10^{10}\mathsf{m}</math>
|<math>1.1177\times10^{7}\mathsf{mi}</math>
|0.12 AU
|-
|1 Light-year
|<math>1.7987\times10^{15}\mathsf{m}</math>
|<math>5.8786\times10^{12}\mathsf{mi}</math>
|63000 AU
|}

== References ==
<references />

@@ Line 2: / Line 2: @@
 '''Light-time''' is the product of the [[speed of light]] in a vacuum and time it takes light to travel a certain distance in space. It is most commonly used in light-years to calculate interstellar distances.<ref>[https://www.merriam-webster.com/dictionary/light-time “Light-Time.”] n.d. In ''Marriam-Webster Dictionary''.</ref>
-For example, the Earth can be said to be 8.3 light minutes from the sun, since it takes 8.3 minutes for light to cross that distance.
+For example, the Earth can be said to be 8.3 light minutes from the sun, since it takes 8.3 minutes for light to cross that distance.  Mars is 13.4 light minutes from the sun.
 ==Common units of light-time==

@@ Line 24: / Line 24: @@
 |-
 |1 Light-hour
-|<math>1.079\times10^{9}\mathsf{m}</math>
+|<math>1.079\times10^{12}\mathsf{m}</math>
 |<math>6.706\times10^{8}\mathsf{mi}</math>
 |7.214 AU

@@ Line 24: / Line 24: @@
 |-
 |1 Light-hour
-|<math>1.079\times10^{9}\mathsf{mi}</math>
+|<math>1.079\times10^{9}\mathsf{m}</math>
-|<math>6.706\times10^{8}\mathsf{m}</math>
+|<math>6.706\times10^{8}\mathsf{mi}</math>
 |7.214 AU
 |-

@@ Line 1: / Line 1: @@
 '''Light-time''' is the product of the [[speed of light]] in a vacuum and time it takes light to travel a certain distance in space. It is most commonly used in light-years to calculate interstellar distances.<ref>[https://www.merriam-webster.com/dictionary/light-time “Light-Time.”] n.d. In ''Marriam-Webster Dictionary''.</ref>
 ==Common units of light-time==
@@ Line 22: / Line 24: @@
 |-
 |1 Light-hour
 |<math>6.706\times10^{8}\mathsf{m}</math>
 |7.214 AU
 |-

@@ Line 26: / Line 26: @@
 |63000 AU
 |}
-For Mars, light time translates into communication times.  For example, it could be said that at its closest Mars is xx minutes away from Earth, while at maximum separation it is xx minutes away.
+For Mars, light time translates into communication times.  For example, it could be said that at its closest Mars is about 4 minutes away from Earth, while at maximum separation it is about 20 minutes away.
 ==References==
 <references />

@@ Line 3: / Line 3: @@
 ==Common units of light-time==
-The light-second, light-minute, and light-year are the most common light-time units used.
+The light-second, light-minute, and light-year (and to a lesser extent light-hour) are the most common light-time units used.
 {| class="wikitable"
 |+Common units of light-time
@@ Line 20: / Line 20: @@
 |<math>1.1177\times10^{7}\mathsf{mi}</math>
 |0.12 AU
 |-
 |1 Light-year

@@ Line 22: / Line 22: @@
 |-
 |1 Light-year
-|<math>1.7987\times10^{15}\mathsf{m}</math>
+|<math>9.4607\times10^{15}\mathsf{m}</math>
 |<math>5.8786\times10^{12}\mathsf{mi}</math>
 |63000 AU