New Mars Forums

Bill White

Member

Registered: 2001-09-09

Posts: 2,114

Re: Can I mooch some free help? - A Mars related question

I was reading today that given our current close proximity to Mars, a radio message (or light) would take 186 seconds to travel from Earth to the Red Planet.

As many of you know, I am writing (quite slowly) a novel-like story about Mars. Here is one nagging technical question perhaps some one could help me with.

Assume it is April 6, 2030. What is the radio transit time (light speed interval) between Earth and Mars as of that date? Is there an easy way to figure out the precise relay time for any particular date?

Bill White

Member

Registered: 2001-09-09

Posts: 2,114

Re: Can I mooch some free help? - A Mars related question

12:01 a.m. on April 6, 2030

US Mountain Time. Daylight or Standard? I don't care. . .

clark

Member

Registered: 2001-09-20

Posts: 6,362

Re: Can I mooch some free help? - A Mars related question

Sorry, the .711 Au is for the Sun- should be 2.409 AU, which translates into 1,245 seconds (one way). Or about 20.75  minutes

April 6th, 2030.

clark

Member

Registered: 2001-09-20

Posts: 6,362

Re: Can I mooch some free help? - A Mars related question

Here is a website to help you out in the future (pardon the pun)

http://www.fourmilab.ch/cgi-bin/uncgi/Solar

you can enter in any date, and it will give you the distance from Earth in AU. From that, just convert 1 AU to 93,000,000 miles (sorry, you foreigners will have to do your own metric conversion) 

Speed of light ? is 186,000.

The rest is math.

Bill White

Member

Registered: 2001-09-09

Posts: 2,114

Re: Can I mooch some free help? - A Mars related question

Awesome website - Many thanks!

Josh Cryer

Moderator

Registered: 2001-09-29

Posts: 3,830

Re: Can I mooch some free help? - A Mars related question

Heh, we're 3 minutes from Mars? That puts it in to perspective more. Wow. Profound.

---

Some useful links while MER are active. [url=http://marsrovers.jpl.nasa.gov/home/index.html]Offical site[/url] [url=http://www.nasa.gov/multimedia/nasatv/MM_NTV_Web.html]NASA TV[/url] [url=http://www.jpl.nasa.gov/mer2004/]JPL MER2004[/url] [url=http://www.spaceflightnow.com/mars/mera/statustextonly.html]Text feed[/url]
--------
The amount of solar radiation reaching the surface of the earth totals some 3.9 million exajoules a year.

Free Spirit

Banned

Registered: 2003-06-12

Posts: 167

Re: Can I mooch some free help? - A Mars related question

Earlier today I read an article about some soothsayers who think the approach of Mars is a portent of doom for all humanity.  Bill maybe you should have some fortune tellers in your story.  Fortune tellers and Mars go hand in hand.

---

My people don't call themselves Sioux or Dakota.  We call ourselves Ikce Wicasa, the natural humans, the free, wild, common people.  I am pleased to call myself that.  -Lame Deer

Shaun Barrett

Member

From: Cairns, Queensland, Australia

Registered: 2001-12-28

Posts: 2,843

Re: Can I mooch some free help? - A Mars related question

Nice work, Clark.   

---

The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down.   - Rita Rudner

Palomar

Member

From: USA

Registered: 2002-05-30

Posts: 9,734

Re: Can I mooch some free help? - A Mars related question

I was reading today that given our current close proximity to Mars, a radio message (or light) would take 186 seconds to travel from Earth to the Red Planet.

*My goodness.  Radio transmission times can vary this much?  I thought I read in _The Case for Mars_ that an average radio transmission takes 40+ minutes to reach Earth (and vice versa). 

Talk about your elliptical orbit factor.

--Cindy

---

We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

clark

Member

Registered: 2001-09-20

Posts: 6,362

Re: Can I mooch some free help? - A Mars related question

Thanks Shaun!

I am a far cry from some of the more mathmatically gifted individuals here, so your praise is appreciated. Especially considering what I have seen of your science and mathmatical understanding.

Algol

Member

From: London

Registered: 2003-04-25

Posts: 196

Re: Can I mooch some free help? - A Mars related question

*My goodness.  Radio transmission times can vary this much?  I thought I read in _The Case for Mars_ that an average radio transmission takes 40+ minutes to reach Earth (and vice versa).

The longest radio transmission time in either direction is roughly 20 minutes, the shortest, i assume is 186 seconds. The 40 minutes is the time it takes to get a response in a conversation or if you ask a question - and thats if you reply instatntly!