APOD: Harvest Moon Trail (2021 Sep 23)

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: Harvest Moon Trail (2021 Sep 23)

Post by APOD Robot » Thu Sep 23, 2021 4:05 am

Image Harvest Moon Trail

Explanation: Famed in festival, story, and song the best known full moon is the Harvest Moon. For northern hemisphere dwellers that's a traditional name of the full moon nearest the September equinox. Seen from Saunderstown, Rhode Island, planet Earth, this Harvest Moon left a broad streak of warm hues as it rose through a twilight sky over the Newport Bridge. On September 20 its trail was captured in a single 22 minute exposure using a dense filter and a digital camera. Only two days later the September equinox marked a change of season and the beginning of autumn in the north. In fact, recognizing a season as the time between solstice and equinox, this Harvest Moon was the fourth full moon of the season, coming just before the astronomical end of northern summer.

<< Previous APOD This Day in APOD Next APOD >>

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

Re: APOD: Harvest Moon Trail (2021 Sep 23)

Post by neufer » Thu Sep 23, 2021 1:21 pm

https://en.wikipedia.org/wiki/The_Pont_Neuf_Wrapped wrote:
Click to play embedded YouTube video.
<<The Pont Neuf Wrapped, Paris, 1975–1985 was a 1985 environmental artwork in which artists Christo and Jeanne-Claude wrapped the Pont Neuf in fabric. Planning for the project started in 1979. The artists put a model of the project in the window of La Samaritaine, a department store close to the bridge, in late 1981. Paris Mayor Jacques Chirac rejected the project in early 1982. An aide to the mayor snuck the permit approval into a pile of the mayor's papers, which he signed inadvertently in August 1984. When the mayor attempted to repeal the approval, Jeanne-Claude said she would show the press the letter as a symbol of his signature's worth, after which he dropped his case. In September 1985, the artists wrapped the bridge and its 44 streetlamps in a sandstone-colored fabric. The two-week installation attracted three million visitors.>>
Art Neuendorffer

User avatar
orin stepanek
Plutopian
Posts: 8200
Joined: Wed Jul 27, 2005 3:41 pm
Location: Nebraska

Re: APOD: Harvest Moon Trail (2021 Sep 23)

Post by orin stepanek » Thu Sep 23, 2021 2:11 pm

full-harvest-moon-california-garry-hayes-oct1-2020-e1601750292749.jpeg
Moon was so bright the other night that it pretty much lit up my
whole bedroom! Twas a beautiful moon! 8-)
Orin

Smile today; tomorrow's another day!

User avatar
johnnydeep
Commodore
Posts: 2777
Joined: Sun Feb 20, 2011 8:57 pm

Re: APOD: Harvest Moon Trail (2021 Sep 23)

Post by johnnydeep » Thu Sep 23, 2021 3:23 pm

From Mike Cohea's twitter feed:


Also from there, the "dense filter" used was a "10-stop ND filter", presumably like one of these - https://www.the-digital-picture.com/Rev ... ilter.aspx:
Why Select a 10-Stop ND Filter
A 10-stop neutral density filter is an extreme version of a neutral density filter, reducing the amount of light transmitted by 1000x. Ten stops, 3.0 density, 1000x and #110 all refer to the same extreme density – practically black. I like to refer to these filters as "Black Filters".

While I selected a 10-stop ND filter for this review, the 9-stop variant is nearly as extreme and is also both commonly available and quite popular. That said, a 10 stop ND [Neutral Density] filter allows 1/2 as much light to pass through as a 9 stop ND filter does. If the 9 stop filter results in a 30 second exposure, a 10 stop filter will provide a 2x longer 60 second exposure that will make a noticeable difference with certain subjects. For example, clouds will create blur paths that are twice as long.
Just another aspect of astrophotography I know nothing about...
--
"To B̬̻̋̚o̞̮̚̚l̘̲̀᷾d̫͓᷅ͩḷ̯᷁ͮȳ͙᷊͠ Go......Beyond The F͇̤i̙̖e̤̟l̡͓d͈̹s̙͚ We Know."{ʲₒʰₙNYᵈₑᵉₚ}

User avatar
Ann
4725 Å
Posts: 13369
Joined: Sat May 29, 2010 5:33 am

Re: APOD: Harvest Moon Trail (2021 Sep 23)

Post by Ann » Thu Sep 23, 2021 4:02 pm


Ha ha, that's so funny!

Ann
Color Commentator

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

Re: APOD: Harvest Moon Trail (2021 Sep 23)

Post by Fred the Cat » Thu Sep 23, 2021 4:25 pm

Here in Mammoth Lakes, CA for my daughter's wedding
IMG_2709.JPG

that same Harvest moon
IMG_2749 (2).JPG
was setting over Mammoth Mountain
IMG_2754 (2).JPG
Freddy's Felicity "Only ascertain as a cat box survivor"

User avatar
Ann
4725 Å
Posts: 13369
Joined: Sat May 29, 2010 5:33 am

Re: APOD: Harvest Moon Trail (2021 Sep 23)

Post by Ann » Thu Sep 23, 2021 6:30 pm

Fred the Cat wrote: Thu Sep 23, 2021 4:25 pm Here in Mammoth Lakes, CA for my daughter's wedding
that same Harvest moon was setting over Mammoth Mountain
Is that a gibbous moon? Really? How can it be so faint? Are those daytime photos?

But gibbous moons are never high in the sky in the daytime, are they?

Ann
Color Commentator

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

Re: APOD: Harvest Moon Trail (2021 Sep 23)

Post by neufer » Thu Sep 23, 2021 8:01 pm

Ann wrote: Thu Sep 23, 2021 6:30 pm
Is that a gibbous moon? Really? How can it be so faint? Are those daytime photos?

But gibbous moons are never high in the sky in the daytime, are they?
https://www.etymonline.com/search?q=gibbous wrote:
Click to play embedded YouTube video.
gibbous (adj.) c. 1400, "bulging, convex," from Late Latin gibbus "hunchbacked," from Latin gibbus "a hump, a hunch," as an adjective, "bulging," from Proto-Italic *gifri- "hump," *gifro- "hump-backed," of uncertain origin. De Vaan suggests a possible cognates in Lithuanian geibus "gawky, plump," geibstu, geibti "become weak;" Norwegian dialect keiv "slanted, wrong," keiva "left hand," perhaps united by a general sense of "bodily defect." Of the moon from early 15c.; also used from 15c. of hunchbacks.
Art Neuendorffer

User avatar
Chris Peterson
Abominable Snowman
Posts: 18102
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA
Contact:

Re: APOD: Harvest Moon Trail (2021 Sep 23)

Post by Chris Peterson » Thu Sep 23, 2021 8:32 pm

Ann wrote: Thu Sep 23, 2021 6:30 pm
Fred the Cat wrote: Thu Sep 23, 2021 4:25 pm Here in Mammoth Lakes, CA for my daughter's wedding
that same Harvest moon was setting over Mammoth Mountain
Is that a gibbous moon? Really? How can it be so faint? Are those daytime photos?

But gibbous moons are never high in the sky in the daytime, are they?

Ann
Looks like it might have been taken today, between 8 and 9 am. The Moon low in the west, the Sun low in the East.
Chris

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

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

Re: APOD: Harvest Moon Trail (2021 Sep 23)

Post by Fred the Cat » Fri Sep 24, 2021 3:46 am

I woke up this morning around 7 and noticed the moon setting. Two years we were here and the crescent was setting in the evening.
IMG_7971 (3).JPG
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: Harvest Moon Trail (2021 Sep 23)

Post by neufer » Fri Sep 24, 2021 2:04 pm

https://en.wikipedia.org/wiki/Mammoth_Mountain#Volcanic_gas_discharge wrote:
<<Mammoth Mountain was formed in a series of eruptions that ended 57,000 years ago. Mammoth is still outgassing large amounts of carbon dioxide out of its south flank, near Horseshoe Lake, causing mazuku in that area. Measurements around the lake found that restrooms and tents had a greater than 1% CO2 concentration (toxic) and a deadly 25% concentration of CO2 in a small cabin. CO2 concentrations of less than 1% are typical and healthy in most soils; however, soil concentrations of CO2 in the tree-kill areas ranged from 20% to 90%. This overabundance of CO2 was found to be the cause of the tree-kills because tree roots need to absorb O2 directly and the high CO2 level reduced available O2. Researchers also determined that Mammoth releases about 1,200 tonnes of CO2 every day. As of 2003, the concentration of carbon dioxide in soil gas at Mammoth Mountain is being monitored on a continuous, year-round basis at four sites—three at Horseshoe Lake and one near the base of Chair 19 at the ski area. In April 2006, three members of the Mammoth Mountain Ski Area ski patrol died while on duty. All three died from suffocation by carbon dioxide when they fell into a fumarole on the slopes of the mountain.

The most likely sources of the CO2 are degassing of intruded magma and gas release from limestone-rich metasedimentary rocks that are heated by magmatic intrusions. The remarkable uniformity in chemical and isotopic composition of the CO2 and accompanying gases at different locations around Mammoth Mountain indicates that there may actually be a large reservoir of gas deep below the mountain from which gas escapes along faults to the surface. Measurements of helium emissions support the theory that the gases emitted in the tree kill area have the same source as those discharged from Mammoth Mountain Fumarole.>>
Art Neuendorffer

Post Reply