Explanation: Lighter than typically dark, smooth, mare the Mare Frigoris lies in the far lunar north. Also known as the Sea of Cold, it stretches across the familiar lunar nearside in this close up of the waxing gibbous Moon's north polar region. Dark-floored, 95 kilometer wide crater Plato is just left of the center. Sunlit peaks of the lunar Alps (Montes Alpes) are highlighted below and right of Plato, between the more southern Mare Imbrium (Sea of Rains) and Mare Frigoris. The prominent straight feature cutting through the mountains is the lunar Alpine Valley (Vallis Alpes). Joining the Mare Imbrium and Mare Frigoris, the lunar valley is about 160 kilometers long and up to 10 kilometers wide.
Ann wrote: ↑Thu Oct 08, 2020 4:18 am
I can see two lunar marias here:
Mare Frigoris.png
Which one is Mare Frigoris?
Ann
The top one is Frigoris while the bottom one is Mare Imbrium. Valles Alpes is a handy route that connects the two if you ever go driving there!
Re: APOD: Mare Frigoris (2020 Oct 08)
Posted: Thu Oct 08, 2020 8:23 am
by DL MARTIN
With all the impact craters evident, does the Moon serve serve as a sort of protective fly trap for Earth?
Re: APOD: Mare Frigoris (2020 Oct 08)
Posted: Thu Oct 08, 2020 10:54 am
by orin stepanek
This must be a more moderate zone on Luna! Possibly a good colony
site? 🏕
Re: APOD: Mare Frigoris (2020 Oct 08)
Posted: Thu Oct 08, 2020 12:39 pm
by De58te
Which one is Mare Frigoris? If we can go by the Jet Propulsion Laboratory Link under Mare Frigoris text, the JPL seem to have drawn it just above Plato Crater. However of the large crater(s) to the right that you included in Mare Frigoris, the JPL have drawn it not to be in the Mare. Frigoris swings around the north sides of the crater.
Re: APOD: Mare Frigoris (2020 Oct 08)
Posted: Thu Oct 08, 2020 2:05 pm
by johnnydeep
DL MARTIN wrote: ↑Thu Oct 08, 2020 8:23 am
With all the impact craters evident, does the Moon serve serve as a sort of protective fly trap for Earth?
Well, I'm sure there were some meteorites that hit the moon instead of hitting the earth had the moon not been there, but because of the moon's small size and large distance (currently about 30 earth diameters) I don't think it is a very effective shield. The profusion of craters on the moon is due to the vastness of time and almost no errosional processes being active on the moon (besides newer impacts wiping out older craters!). That said, lunar impacts seem to be pretty frequent, as these stories from 2013 and 2019 indicate:
Video footage of the record-breaking meteorite strike on the moon, which occurred on Sept. 11, 2013 and was unveiled today (Feb. 24), shows a long flash that was almost as bright as the North Star Polaris. That means the boulder-sized meteorite's lunar crash could have been visible to anyone on Earth who happened to be staring up at the moon at 8:07 p.m. GMT, weather permitting.
...
The space rock hit at a staggering speed of 37,900 mph (61,000 km/h), gouging out a new crater roughly 131 feet (40 meters) wide in an ancient lava-filled lunar basin known as Mare Nubium, Madiedo and colleagues said. The scientists think the boulder behind the crash was about 880 lbs. (400 kg) and measured between 2 and 4.5 feet (0.6 and 1.4 meters) in diameter.
If a space rock this size hit the Earth, it might create some spectacular fireball meteors, but it likely would not pose a threat to people on the ground, researchers explained. But the moon lacks an atmosphere like the one enshrouding our planet, making it quite vulnerable to incoming asteroids.
A meteorite smashed into the moon's surface at 38,000 miles per hour (61,000 kilometers per hour) while our lunar neighbor was in total eclipse in January, a new report reveals.
Observers saw a flash during the Jan. 20 to 21 [2019] eclipse, when the object collided with the moon and carved out a crater about 10 to 15 meters (33 to 50 feet) in diameter. It was traveling fast enough to have been able to cross the United States in just a few minutes, but, luckily for Earth, it slammed into the moon instead.
Astronomers measured a 0.28-second flash from the impact, the first ever filmed during a lunar eclipse. Lunar eclipses happen when the moon passes into the Earth's shadow during its normal orbit around our planet. The moon turns a reddish or orange color, because only sunlight around the edges of Earth's shadow can reach the moon's surface.
Re: APOD: Mare Frigoris (2020 Oct 08)
Posted: Thu Oct 08, 2020 2:26 pm
by DL MARTIN
Thanks for clarifying my query regarding the Moon's possible protective role.
Re: APOD: Mare Frigoris (2020 Oct 08)
Posted: Thu Oct 08, 2020 3:31 pm
by rj rl
johnnydeep wrote: ↑Thu Oct 08, 2020 2:05 pm
lunar impacts seem to be pretty frequent, as these stories from 2013 and 2019 indicate:
measured between 2 and 4.5 feet (0.6 and 1.4 meters) in diameter.
quite a flash for how small it was.
Re: APOD: Mare Frigoris (2020 Oct 08)
Posted: Thu Oct 08, 2020 3:34 pm
by Dtuggy
Hey, you all, learn the Latin plurals of these wierd names: mare - maria , nebula - nebulae and so forth. It is embarrassing to have them misrepresented in so public and prestigious a forum as APOD is.
Re: APOD: Mare Frigoris (2020 Oct 08)
Posted: Thu Oct 08, 2020 5:35 pm
by Ann
Dtuggy wrote: ↑Thu Oct 08, 2020 3:34 pm
Hey, you all, learn the Latin plurals of these wierd names: mare - maria , nebula - nebulae and so forth. It is embarrassing to have them misrepresented in so public and prestigious a forum as APOD is.
Hey, Dtuggy, I have started writing "nebulas" because our resident astronomer, Chris Peterson, urged me to do so.
But I did write "maria", because "mares" just didn't seem right to me.
Dtuggy wrote: ↑Thu Oct 08, 2020 3:34 pm
Hey, you all, learn the Latin plurals of these wierd names: mare - maria , nebula - nebulae and so forth. It is embarrassing to have them misrepresented in so public and prestigious a forum as APOD is.
Hey, Dtuggy, I have started writing "nebulas" because our resident astronomer, Chris Peterson, urged me to do so.
But I did write "maria", because "mares" just didn't seem right to me.
Dtuggy wrote: ↑Thu Oct 08, 2020 3:34 pm
Hey, you all, learn the Latin plurals of these wierd names: mare - maria , nebula - nebulae and so forth. It is embarrassing to have them misrepresented in so public and prestigious a forum as APOD is.
Hey, Dtuggy, I have started writing "nebulas" because our resident astronomer, Chris Peterson, urged me to do so.
But I did write "maria", because "mares" just didn't seem right to me.
And "nebulas" is pretty nebulous. (So you saw horse in "mares" )
Re: APOD: Mare Frigoris (2020 Oct 08)
Posted: Thu Oct 08, 2020 8:23 pm
by Ann
neufer wrote: ↑Thu Oct 08, 2020 7:09 pm
And "nebulas" is pretty nebulous. (So you saw horse in "mares" )
https://oz.fandom.com/wiki/Sawhorse wrote:
"The Saw-Horse, finding himself alive, seemed even more astonished than Tip. He rolled his knotty eyes from side to side, taking a first wondering view of the world in which he had now so important an existence. Then he tried to look at himself; but he had, indeed, no neck to turn; so that in the endeavor to see his body he kept circling around and around, without catching even a glimpse of it. His legs were stiff and awkward, for there were no knee-joints in them; so that presently he bumped against Jack Pumpkinhead and sent that personage tumbling upon the moss that lined the roadside." ―The Marvelous Land of Oz (1904)
Re: APOD: Mare Frigoris (2020 Oct 08)
Posted: Fri Oct 09, 2020 1:17 am
by MarkBour
Dtuggy wrote: ↑Thu Oct 08, 2020 3:34 pm
Hey, you all, learn the Latin plurals of these wierd names: mare - maria , nebula - nebulae and so forth. It is embarrassing to have them misrepresented in so public and prestigious a forum as APOD is.
My Latin is weaker than hobo's tea on a rainy night. Hmmm . . . maybe Google will help.
Always fun to do a translation round-trip (It works a bit better if we correct the spelling of "wierd") :
=---> Latin:
Heus, vos omnes disce Latinam plural horum fatum nomina: mare - maria, nebula - nebulae vel aliquid huiusmodi. Ad hoc incommodi, quod apud eos tam publica detorta ac pro prestigious a foro APOD sit.
=---> English
Hey, you learn Latin plural of these weird names: Sea - seas, fog - fog or the like. To this disadvantage, that they are with them as much as it is the public could warp, APOD from the market, and for the most prestigious.
And after 5 round trips, it stabilizes at:
Hey you learn Latin plural of these weird names: Sea - seas, fog - fog or the like. That flaw not only of the glory of the state of the course of the warp, apad.
Anyway, it's nice to learn that it's prestigious here.
Dtuggy wrote: ↑Thu Oct 08, 2020 3:34 pm
Hey, you all, learn the Latin plurals of these wierd names: mare - maria , nebula - nebulae and so forth. It is embarrassing to have them misrepresented in so public and prestigious a forum as APOD is.
My Latin is weaker than hobo's tea on a rainy night. Hmmm . . . maybe Google will help.
Always fun to do a translation round-trip (It works a bit better if we correct the spelling of "wierd") :
=---> Latin:
Heus, vos omnes disce Latinam plural horum fatum nomina: mare - maria, nebula - nebulae vel aliquid huiusmodi. Ad hoc incommodi, quod apud eos tam publica detorta ac pro prestigious a foro APOD sit.
=---> English
Hey, you learn Latin plural of these weird names: Sea - seas, fog - fog or the like. To this disadvantage, that they are with them as much as it is the public could warp, APOD from the market, and for the most prestigious.
And after 5 round trips, it stabilizes at:
Hey you learn Latin plural of these weird names: Sea - seas, fog - fog or the like. That flaw not only of the glory of the state of the course of the warp, apad.
Anyway, it's nice to learn that it's prestigious here.
Mark, I love it. My mastery of German being (very) questionable, I once used Google translate to translate a German-language article about Eta Carina (Carinae, for those so inclined) into English.
It should come as no surprise that the Homonculus nebula was described as a fog. More interesting to me was that Eta Carina - oops, dropped the "e" - was referred to as an "asterisk", like in Starship! ➽ ✱
Ah, Eta Carina-e, Sic transit gloria cosmi!
Ann
Re: APOD: Mare Frigoris (2020 Oct 08)
Posted: Fri Oct 09, 2020 9:49 am
by MarkBour
Ann wrote: ↑Fri Oct 09, 2020 4:45 am
Ah, Eta Carina-e, Sic transit gloria cosmi!
Ann
Ah, Eta Carina ! Sic transit gloria cosmi -- thus passeth the glory of the heavens, in ictu supernovae, with such haste to become but an asterisk in a fog.
Ann, I think you have the beginnings of a grand poem.
Re: APOD: Mare Frigoris (2020 Oct 08)
Posted: Fri Oct 09, 2020 3:46 pm
by johnnydeep
MarkBour wrote: ↑Fri Oct 09, 2020 1:50 am
It's interesting to look just a bit to the south of the APOD
field of view. Wikipedia has a wonderful image of
Mare Imbrium, a composed mosaic:
- pic elided -
I cannot imagine the impact that caused this (but I enjoy trying!)
The entire range of the Lunar Alps appear to be just one part
of the result.
Plato, at top center, appears relatively small compared to it.
Wikipedia indicates that Plato was formed after Mare Imbrium.
Since I'd bet that we probably know the relative ages of a great many of the craters on the moon, I would love to see a time-lapse movie compressing the last 4 billion years of lunar impacts into maybe 5 minutes. 'Twould make for quite a show, especially on July Fourth! (at least for my American friends)
Re: APOD: Mare Frigoris (2020 Oct 08)
Posted: Sat Oct 10, 2020 11:58 pm
by MarkBour
johnnydeep wrote: ↑Fri Oct 09, 2020 3:46 pm
Since I'd bet that we probably know the relative ages of a great many of the craters on the moon, I would love to see a time-lapse movie compressing the last 4 billion years of lunar impacts into maybe 5 minutes. 'Twould make for quite a show, especially on July Fourth! (at least for my American friends)
Mare Frigoris
🏕 
)
➽ ✱ 
