It would be more scientific to say "How long is seven sols (Martian days)?" instead of "How long is one week on Mars?" Anyway, let's do this calculation in simple mathematical steps:
We first have to find out how many hours 7 sols is equivalent to. We know that a sol is 24.6 hrs (24 hrs and 39 mins) long, so we have to multiply 24.6 by 7 to see how many hrs 7 sols is equal to.
24.6 X 7 = 172.2 hrs
So we have found out that 7 sols (one Martian week) is equal to 172.2 hrs. Now, we have to convert 172.2 hrs to earth days by dividing 172.2 hrs by 24 hrs (the length of an Earth Day).
172.2 / 24 = 7.175 Earth days
Finally, we have to convert the .175 days to hrs and mins. We do this by multiplying .175 by 24 to convert into hrs and then multiplying the decimal part of the result by 60 to also get the mins.
.175 X 24 = 4.2 hrs
.2 X 60 = 12 mins
So in conclusion, we have found that one Martian week (7 Martian days) is equivalent to 7 Earth days, 4 hrs, and 12 mins, which is 4 hrs and 12 mins longer than an Earth week (seven Earth days).
A week is defined as a period of 7 days. So a Mar's week is also seven days. Curiously a day on Mars is only 24.622 Earth hours
Friday
Mars has no rivers.
For ever!
It's Jupiter that has the long lived storm, not Mars
Mars is 6,794 km in diameter
A mars day is about a hundred hours!
Curiousity Rover You can know more about it at Wikepedia, the free encyclopedia
Grenade by Bruno Mars
mars Saturn Pluto
This week it is When I was Your Man by Bruno Mars
Holy week is one entire week.