APOD: Valles Marineris: The Grand Canyon... (2016 May 29)

Comments and questions about the APOD on the main view screen.
Post Reply
User avatar
APOD Robot
Otto Posterman
Posts: 5344
Joined: Fri Dec 04, 2009 3:27 am
Contact:

APOD: Valles Marineris: The Grand Canyon... (2016 May 29)

Post by APOD Robot » Sun May 29, 2016 4:06 am

Image Valles Marineris: The Grand Canyon of Mars

Explanation: Mars will look good in Earth's skies over the next few days -- but not this good. To get a view this amazing, a spacecraft had to actually visit the red planet. Running across the image center, though, is one the largest canyons in the Solar System. Named Valles Marineris, the grand valley extends over 3,000 kilometers long, spans as much as 600 kilometers across, and delves as much as 8 kilometers deep. By comparison, the Earth's Grand Canyon in Arizona, USA is 800 kilometers long, 30 kilometers across, and 1.8 kilometers deep. The origin of the Valles Marineris remains unknown, although a leading hypothesis holds that it started as a crack billions of years ago as the planet cooled. Several geologic processes have been identified in the canyon. The featured mosaic was created from over 100 images of Mars taken by Viking Orbiters in the 1970s. Tomorrow, Mars and Earth will pass the closest in 11 years, resulting in the red planet being quite noticeable toward the southeast after sunset.

<< Previous APOD This Day in APOD Next APOD >>
[/b]

old dude

Re: APOD: Valles Marineris: The Grand Canyon... (2016 May 29)

Post by old dude » Sun May 29, 2016 4:42 am

What's 'The Grand Canyon'?

Boomer12k
:---[===] *
Posts: 2691
Joined: Sun Apr 22, 2007 12:07 am

Re: APOD: Valles Marineris: The Grand Canyon... (2016 May 29)

Post by Boomer12k » Sun May 29, 2016 5:36 am

Would like to get out and get a shot, I could do that tonight, but don't feel well, and it is breezy, and I just am not up to it... in a few days it will be warmer... so, hopefully...

:---[===] *

mugs1

Re: APOD: Valles Marineris: The Grand Canyon... (2016 May 29)

Post by mugs1 » Sun May 29, 2016 12:50 pm

How accurate is the 11 year cycle of the earth and mars being at their closest proximity as stated in todays discussion? I ask this as I wonder if it is not perhaps more accurate at a time frame of 10.75 years which aligns with the Pi number cycle as it relates mankinds time numbering system.?

User avatar
Case
Commander
Posts: 616
Joined: Sat Jun 09, 2007 10:08 pm
Location: (52°N, 06°E)

Re: APOD: Valles Marineris: The Grand Canyon... (2016 May 29)

Post by Case » Sun May 29, 2016 2:58 pm

mugs1 wrote:How accurate is the 11 year cycle of the earth and mars being at their closest proximity as stated in todays discussion?
It is not an 11 year cycle. It was 11 years ago (2005) that Mars was a bit closer to Earth than this year. 2003 was even closer, 2018 will be closer, too.

User avatar
Fred the Cat
Theoretic Apothekitty
Posts: 958
Joined: Mon Feb 22, 2016 4:09 pm
AKA: Ron
Location: Eagle, Idaho

Re: APOD: Valles Marineris: The Grand Canyon... (2016 May 29)

Post by Fred the Cat » Sun May 29, 2016 3:41 pm

As the link today says "Vallis Marineris" stretches 3,000 miles. That would change the US's highway system! Imagine the bridges? :roll:
Freddy's Felicity "Only ascertain as a cat box survivor"

User avatar
neufer
Vacationer at Tralfamadore
Posts: 18805
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

Re: APOD: Valles Marineris: The Grand Canyon... (2016 May 29)

Post by neufer » Sun May 29, 2016 6:41 pm

Fred the Cat wrote:
As the link today says "Vallis Marineris" stretches 3,000 miles.
That would change the US's highway system! Imagine the bridges? :roll:
That would change The Intracoastal Waterway system.
https://en.wikipedia.org/wiki/Intracoastal_Waterway wrote:
<<The Intracoastal Waterway (ICW) is a 3,000-mile inland waterway along the Atlantic and Gulf of Mexico coasts of the United States. Some sections of the waterway consist of natural inlets, saltwater rivers, bays, and sounds, while others are artificial canals. It provides a navigable route along its length without many of the hazards of travel on the open sea.>>
Art Neuendorffer

User avatar
Fred the Cat
Theoretic Apothekitty
Posts: 958
Joined: Mon Feb 22, 2016 4:09 pm
AKA: Ron
Location: Eagle, Idaho

Re: APOD: Valles Marineris: The Grand Canyon... (2016 May 29)

Post by Fred the Cat » Mon May 30, 2016 4:13 pm

neufer wrote:
Fred the Cat wrote:
As the link today says "Vallis Marineris" stretches 3,000 miles.
That would change the US's highway system! Imagine the bridges? :roll:
That would change The Intracoastal Waterway system.
https://en.wikipedia.org/wiki/Intracoastal_Waterway wrote:
<<The Intracoastal Waterway (ICW) is a 3,000-mile inland waterway along the Atlantic and Gulf of Mexico coasts of the United States. Some sections of the waterway consist of natural inlets, saltwater rivers, bays, and sounds, while others are artificial canals. It provides a navigable route along its length without many of the hazards of travel on the open sea.>>

Yes and maybe the Basque who settled in the US could have continued as fisherman instead of settling as sheepherders in Idaho. :?: I'm glad it turned out as it did. We love their culture here. And their food :!:
Freddy's Felicity "Only ascertain as a cat box survivor"

User avatar
Asterhole
Ensign
Posts: 62
Joined: Fri Oct 30, 2015 2:27 pm
Location: Solar System

Re: APOD: Valles Marineris: The Grand Canyon... (2016 May 29)

Post by Asterhole » Tue May 31, 2016 4:55 pm

What is obvious to me is that in this image the scale of Valles Marineris is way too large. It looks to stretch across a third of the planet at the equator when it's actually something more like a tenth located in the northern hemisphere. Oh and it's 3000 kilometers, not miles so...
They're all wasted!

User avatar
Chris Peterson
Abominable Snowman
Posts: 18111
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA
Contact:

Re: APOD: Valles Marineris: The Grand Canyon... (2016 May 29)

Post by Chris Peterson » Tue May 31, 2016 5:19 pm

Asterhole wrote:What is obvious to me is that in this image the scale of Valles Marineris is way too large. It looks to stretch across a third of the planet at the equator when it's actually something more like a tenth located in the northern hemisphere. Oh and it's 3000 kilometers, not miles so...
The scale is fine. This image was constructed based on an observation height of 2500 km. That means that we're seeing 110° of Mars from horizon to horizon, or a distance of 6500 km. It also means that there's a lot of foreshortening towards the edges. Here's the geometry of the image, showing the observation point, horizons, and the angle subtended by VM, assuming a 3000 km length.
Capture.PNG
Capture.PNG (6.05 KiB) Viewed 2614 times
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
https://www.cloudbait.com

Post Reply