APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

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APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

Post by APOD Robot » Fri Jan 26, 2018 5:11 am

Image Selfie at Vera Rubin Ridge

Explanation: On sol 1943 of its journey of exploration across the surface of Mars, the Curiosity Rover recorded this selfie at the south rim of Vera Rubin Ridge. Of course a sol is a Martian solar day, about 40 minutes longer than an Earth day. Curiosity's sol 1943 corresponds to Earth date January 23, 2018. Also composed as an interactive 360 degree VR, the mosaicked panorama combines 61 exposures taken by the car-sized rover's Mars Hand Lens Imager (MAHLI). Frames containing the imager's arm have been edited out while the extended background used was taken by the rover's Mastcam on sol 1903. At the top of the rover's mast, sitting above the Mastcam, the laser-firing ChemCam housing blocks out the distant peak of Mount Sharp.

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heehaw

Re: APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

Post by heehaw » Fri Jan 26, 2018 9:58 am

It looks like it is in orbit AROUND Mars!

Mountainjim62

Re: APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

Post by Mountainjim62 » Fri Jan 26, 2018 9:00 pm

Seeing the Sun in the 360 degree view made me wonder, are there any pictures of Mars moon taken from Mars?

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Re: APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

Post by Chris Peterson » Fri Jan 26, 2018 9:07 pm

Mountainjim62 wrote:Seeing the Sun in the 360 degree view made me wonder, are there any pictures of Mars moon taken from Mars?
Yes. Daytime and nighttime pictures of both, as well as a solar transit by Deimos.
Chris

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mountainjim62

Re: APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

Post by mountainjim62 » Fri Jan 26, 2018 9:30 pm

Chris Peterson wrote:
Mountainjim62 wrote:Seeing the Sun in the 360 degree view made me wonder, are there any pictures of Mars moon taken from Mars?
Yes. Daytime and nighttime pictures of both, as well as a solar transit by Deimos.
Thank you. Just check a few out. Very cool. I still have a copy of Life magazine from May 1, 1991 on which the cover has a picture of Mars and says "Our Next Home". Fascinating to see where we are now compared to the Article written nearly 30 years ago.

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Re: APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

Post by FLPhotoCatcher » Fri Jan 26, 2018 10:46 pm

Seeing that Earth's moon is slowing the rotation of Earth, and Mars' moon is not (much?), how long will it be before the two planet's days are the same length?

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Re: APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

Post by Boomer12k » Fri Jan 26, 2018 11:26 pm

Really nice.... I half expect a giant worm to rise up and eat it....

There is a blue arrow when you turn around in the picture on their website.... hovering on it says..."Psychiatric Hospital".....?????

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Re: APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

Post by Boomer12k » Fri Jan 26, 2018 11:33 pm

FLPhotoCatcher wrote:Seeing that Earth's moon is slowing the rotation of Earth, and Mars' moon is not (much?), how long will it be before the two planet's days are the same length?
I hate "Story Problems".... I was really bad at them...

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Re: APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

Post by neufer » Fri Jan 26, 2018 11:53 pm

FLPhotoCatcher wrote:
Seeing that Earth's moon is slowing the rotation of Earth, and Mars' moon is not (much?),
how long will it be before the two planet's days are the same length?
About 132 million years.

Phobos will be destroyed (i.e., turned into a ring) in ~40 million years.
Art Neuendorffer

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Re: APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

Post by MarkBour » Sat Jan 27, 2018 1:26 am

neufer wrote:
FLPhotoCatcher wrote:
Seeing that Earth's moon is slowing the rotation of Earth, and Mars' moon is not (much?),
how long will it be before the two planet's days are the same length?
About 132 million years.

Phobos will be destroyed (i.e., turned into a ring) in ~40 million years.
I'm putting my money on 104 million years. Care to make a small wager on it?
Mark Goldfain

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Re: APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

Post by neufer » Sat Jan 27, 2018 4:49 am

MarkBour wrote:
neufer wrote:
FLPhotoCatcher wrote:
Seeing that Earth's moon is slowing the rotation of Earth, and Mars' moon is not (much?),
how long will it be before the two planet's days are the same length?
About 132 million years.

Phobos will be destroyed (i.e., turned into a ring) in ~40 million years.
I'm putting my money on 104 million years. Care to make a small wager on it?
Assuming man ain't going to be around for another 6 million years to muck up the planet...sure you're on, Mark :!:
https://en.wikipedia.org/wiki/Tidal_acceleration#Angular_momentum_and_energy wrote:
The geological record is consistent with these conditions:
620 million years ago the day was 21.9±0.4 hours
The day has lengthened ~126 minutes in 620 million years.

Ergo: the day should lengthened ~37.37 minutes in 184 million years
(or longer as the receding moon's effect drops over time).
Art Neuendorffer

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Chris Peterson
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Re: APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

Post by Chris Peterson » Sat Jan 27, 2018 5:10 am

neufer wrote: The day has lengthened ~126 minutes in 620 million years.

Ergo: the day should lengthened ~37.37 minutes in 184 million years
(or longer as the receding moon's effect drops over time).
It's a reasonable estimate, but it could be quite a bit off. The geological record also suggests that the rate has been very nonuniform, possibly remaining unchanged for millions of years at a time and undergoing rapid shifts at other times, subject perhaps to changes in crust position and glaciation.
Chris

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Re: APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

Post by MarkBour » Sun Jan 28, 2018 2:53 am

Chris Peterson wrote:
neufer wrote: The day has lengthened ~126 minutes in 620 million years.

Ergo: the day should lengthened ~37.37 minutes in 184 million years
(or longer as the receding moon's effect drops over time).
It's a reasonable estimate, but it could be quite a bit off. The geological record also suggests that the rate has been very nonuniform, possibly remaining unchanged for millions of years at a time and undergoing rapid shifts at other times, subject perhaps to changes in crust position and glaciation.
You two can out-reason me on orbital mechanics any day. But with so many unknowns, I'll stand by my guess for now.
  • If you give us 100 million years, humanity might get into the act. Every time Elon fires another rocket into a prograde orbit (especially a BFR) ...
  • And what about those gravity assists towards outer planets? Don't those slow down the Earth's rotation ?
  • With any luck, we'll be transporting some material to the Moon (but material moved the other way would favor the longer estimate).
  • Of course asteroid mining is just going to screw everything up.
I know -- you'll probably prove mathematically that it would take 50,000 rockets to have a measurable effect.

Anyway, if I'm way off, then in about 110 million years, when Earth's day is still not quite as long as the Martian day, I'll gladly pay up. :-)
Mark Goldfain

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Re: APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

Post by neufer » Sun Jan 28, 2018 7:43 pm

MarkBour wrote:
Anyway, if I'm way off, then in about 110 million years, when Earth's day is still not quite as long as the Martian day, I'll gladly pay up. :-)
I hope that you will take inflation into account.
Art Neuendorffer

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Re: APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

Post by MarkBour » Mon Jan 29, 2018 5:14 pm

neufer wrote:
MarkBour wrote: Anyway, if I'm way off, then in about 110 million years, when Earth's day is still not quite as long as the Martian day, I'll gladly pay up. :-)
I hope that you will take inflation into account.
Perhaps ... I was thinking to make it a fixed amount of bitcoin.
Mark Goldfain

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Re: APOD: Selfie at Vera Rubin Ridge (2018 Jan 26)

Post by neufer » Tue Mar 27, 2018 8:21 pm

Click to play embedded YouTube video.
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