Talk:Olympus Mons

Height of Olympus Mons is given in this article as 27 km, but was given as 25 km in the [[Mars (planet) article. I have adjusted to make both articles read the same. BUT there is no mention of how these different heights are calculated. As there is no "sea level" on Mars, as there is no sea of free water, what height datum is used? On Mars is the height above mean surface level used or is the height based on elevation above surrounding landscape? I understand Olympus Mons sits in a depression 2 km below mean surface level - this would account for the 2 km discrepancy between the articles. -- kiwiinapanic 09:18 12 Jul 2003 (UTC)

According to the Mars Team Online the measurement of elevation is from the mean. Just as you suspected. I would go with that until somebody has a more authoritative answer.

http://quest.arc.nasa.gov/mars/ask/terrain-geo/Lowest_Elevation_on_Mars.txt

mirwin

My copy of The New Atlas of the Universe lists the height as 25 km above surface level. --Dante Alighieri 10:06 12 Jul 2003 (UTC)

Average surface level or local surface level? ;) -- Oliver P. 10:18 12 Jul 2003 (UTC)

Hehe, I forgot to type that in. Mean. --Dante Alighieri 20:01 12 Jul 2003 (UTC)

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So - how big is Olympus Mons?! I found a variety of answers:

[1] (http://hypertextbook.com/facts/2001/MarinaTsukerman.shtml)	29 km above base	600 km diameter
[2] (http://hypertextbook.com/facts/2001/MarinaTsukerman.shtml)	29 km high	500 km dia
[3] (http://hypertextbook.com/facts/2001/KevinSookdeo.shtml)	27 km high	700 km dia
[4] (http://hypertextbook.com/facts/2001/KevinSookdeo.shtml)	27 km high	>600 km dia
[5] (http://www.lpi.usra.edu/publications/slidesets/hawaiivolcanoes/slidespages/slide_01.html)	27 km above base	600 km dia
[6] (http://quest.arc.nasa.gov/mars/ask/terrain-geo/highest_and_lowest_points_on_Mars.txt)	27 km above datum
[7] (http://quest.arc.nasa.gov/mars/ask/terrain-geo/Height_of_Martian_vs__Earth_mountains.txt)	27 km above datum
[8] (http://www.lpi.usra.edu/publications/slidesets/ss_tour/slide_16.html)	26 km above base	500 km dia
[9] (http://hypertextbook.com/facts/2001/KevinSookdeo.shtml)	25 km above base	800 km dia
[10] (http://hypertextbook.com/facts/2001/KevinSookdeo.shtml)	25 km high	700 km dia
[11] (http://marsprogram.jpl.nasa.gov/gallery/atlas/olympus-mons.html)	25 km above base	624 km dia
[12] (http://starryskies.com/solar_system/mars_html/mars_surface.html)	25 km above base	600 km dia
[13] (http://www.space.com/imageoftheday/image_of_day_040211.html)	25 km above base	550 km dia
[14] (http://www.lpi.usra.edu/publications/slidesets/redplanet2/slide_11.html)	<25 km above base	600 km dia
[15] (http://quest.arc.nasa.gov/mars/ask/terrain-geo/Determining_0_DATUM_or_Sea_Level_on_Mars.txt)	25 km above datum
[16] (http://www.solarviews.com/eng/marsvolc.htm)	24 km above base (to caldera?)	550 km diameter	2.4-2.8 km deep caldera
[17] (http://hypertextbook.com/facts/2001/MarinaTsukerman.shtml)	24 km above base	>500 km dia
[18] (http://hypertextbook.com/facts/2001/MarinaTsukerman.shtml)	24 km high	480 km dia
[19] (http://www.math.montana.edu/~nmp/materials/ess/geosphere/expert/activities/)	24 km above datum
[20] (http://hypertextbook.com/facts/2001/MarinaTsukerman.shtml)	22 ±1 km above base
[21] (http://www.newscientist.com/news/news.jsp?id=ns99994673)	22 km above base
[22] (http://216.239.57.104/search?q=cache:kHFAM6-rVrEJ:www.lpi.usra.edu/meetings/lpsc2002/pdf/1409.pdf+olympus+mons+height+caldera+mars&hl=en&ie=UTF-8)	21.618 km high
[23] (http://216.239.57.104/u/lpi?q=cache:J4OpgxMG12oJ:www.lpi.usra.edu/education/MarsMillennium/olym.pdf+olympus+mons&hl=en&ie=UTF-8)	21 km high	600 km dia
[24] (http://www.lpi.usra.edu/expmars/basicfacts.html)	21 km high	600 km dia

The bit about Olympus standing "in a two-kilometre-deep depression" is wrong - see the topo map o' Mars (http://en.wikipedia.org/wiki/Image:MarsTopoMap-PIA02031_modest.jpg) - though it makes a difference if you measure the "height from the base" on the east or west side. --wwoods 08:14, 7 May 2004 (UTC)

First ascent

In the style of the Wikipedia:Million pool, in which participants attempt to name the day on which the English Wikipedia reaches one million articles, I suggest we all place bets on the timing of the first ascent of Olympus Mons, so that future generations of Wikipedians will be able to laugh at our comically inaccurate predictions. The competition closes to new entries on the day the first manned mission reaches Mars. Nearest person wins eternal fame and a Mars Bar. — Trilobite (Talk) 06:53, 28 Feb 2005 (UTC)

• 29 May 2053 — Trilobite (Talk) 06:53, 28 Feb 2005 (UTC)
• 9 July 2078 — same day Wikipedia reaches 5 million articles :) Worldtraveller 12:46, 3 Mar 2005 (UTC)
• Never — The human race will be replace by cybrogs, robots, ect, thus it's unlike "man" will ever ascend Olympus (i'm serious), perhaps some form of human successor or transhuman being will climb it though, if i'm wrong it will at least make a good laugh.--BerserkerBen 03:34, 9 May 2005 (UTC)
• 17 March 2087 — the day I would supposedly turn 100. I doubt I'll be alive then so if by some weird chance I win, give the Mars Bar to my pal Ashleigh. 青い(Aoi) 05:10, 9 May 2005 (UTC)
• 19 October 2067 bob rulz 11:54, Jun 21, 2005 (UTC)

Atmosphere of Mars and Olympus

According to charts like these [25] (http://www.daviddarling.info/images/Mars_atmosphere1.jpg) at Olympus mon's peak the atmospheric pressure is 1/60 average Martian surface pressure and that high altitude cloud cover is still possible, thus Olympus mons is still within the Martian atmosphere. Despite the Martian average atmospheric pressure being .006th our’s, the much lower gravity at mars allows it’s atmosphere to extend much higher. --BerserkerBen 03:34, 9 May 2005 (UTC)

I slightly adjusted your paragraph, in amongst other changes I made to the article like sectioning and moving some paragraphs around. Didn't change the sense of it, just slightly adjusted the wording and did some copyediting. Worldtraveller 10:21, 9 May 2005 (UTC)