Astronomy Group

[SeanPatrick]

Originally Posted by Astrochef

I [...] am very intrigued by celestial navigation, but starting this late in life, odds are I'm just an aspiring coastal cruiser at best. I can see myself sort of "dabbling" though, just to see if I can learn it... eventually.

If you have any questions or need any kind of assistance at all, I'd be more than happy to help! Celestial navigation doesn't have to be difficult or tedious. And it still has it's place as an independent cross-check on other position finding systems, such as GNSS (GPS). Besides that, I've found it to be a very satisfying endeavor. Finding your position on this earth using only the stars and a couple of mirrors feels almost like magic.

Cheers!

[ChrisJHC]

Originally Posted by SeanPatrick

Yes! That's exactly what I think every time I look up at the night sky!

BTW, I just joined the astronomy group (even though it appears there has been no activity there since about 2018). Anyway, here is a copy of my recent post there:



This is my new Celestron Omni XLT 120mm telescope. A gift to myself for my 45th birthday. It has a focal length of 1000mm. So, with the 25mm, 20mm and 10mm eyepieces I have, combined with my 2x and 3x Barlow lenses, I can choose from magnifications of 40x, 50x, 80x, 100x, 120x, 150x, 200x and 300x.

I also bought a "zoom" lens, which can be set anywhere from 8mm to 24mm, giving a range of magnification of 41.6666...x to 375x with the 3x Barlow. However, the maximum useful magnification of this telescope is 283x, so I only use the 2x Barlow with it for a maximum magnification of 250x.

So far, I have observed Jupiter, Saturn and the Moon. The views were amazing, and that is an understatement. I could clearly see the Galilean Moons and some of the bands in Jupiter's atmosphere. I could just barely make out the Cassini Division in Saturn's rings. And I could see details of the mountains in the middle of the Moon's craters.

I assume the guitar is there to help you fine tune your sights?

[Jamme]

Originally Posted by ChrisJHC

I assume the guitar is there to help you fine tune your sights?

To write wonderful new songs after getting inspired by the stars! 🤩

[GordMay]

The Full Moon of October 28-29 is 2023's "Hunter's Moon".

If you have clear skies Saturday night, look up at moonrise, to check out the Full Hunter's Moon, and you might catch a lunar eclipse in progress.

October's Full Moon rises on the night of the 28th. Named the "Hunter's Moon", this particular Full Moon may appear a bit strange to observers, at the start of the night — not as bright as it should be, and from some regions of Atlantic Canada, and the Far North, it will look as though it is partly dipped in shadow.

[CaptTom]

OK, since this is an Astronomy thread, I think I can get away with airing a pet peeve of mine.

It's a full moon. They happen every 28 days or so. No need to give them cute names like "Hunter." We already have names for the months, and the seasons. We even have a name for the second full moon of the month.

Along the same theme, the spring tide near the moon's perigee already has a name: perigean tide. "Super tide" is just a phrase coined by some journalist looking for click bait, or maybe they couldn't spell perigean. These, too, happen 2-3 times per year. It's not headline material. We shouldn't encourage this silliness by repeating it.

And don't get me started about The Weather Channel naming every little snowstorm. We know it snows here in the mid and northern latitudes. We live here. Just give us a prediction as to how much. You don't need to name it.

Sorry. I'm done. I feel better now.

[SeanPatrick]

Originally Posted by ChrisJHC

I assume the guitar is there to help you fine tune your sights?

It was the nearest thing I had for scale. Yes, I have no bananas.

Originally Posted by CaptTom

We even have a name for the second full moon of the month.

Ah, yes!

[GordMay]

Up next the Taurids and Leonids

The Taurid meteor shower and the Leonids meteor shower will each peak in November.
➥ https://earthsky.org/astronomy-essen...-shower-guide/

The Taurids come from dust and debris, left behind by Comet Encke, and can be seen throughout November and December.
The Taurid meteor shower actually consists of two streams — the Southern Taurids, which peaked between November 4 and 5, and the Northern Taurids, which peak between November 11 and 12.

The Leonid meteor shower will peak on November 18, offering the chance to see fast-moving, bright shooting stars.
In fact, the Leonids, which come from Comet 55P/Tempel-Tuttle, are considered to be some of the fastest meteors, traveling at speeds of 71 kilometers per second, according to NASA.
To see the Leonids at their peak, it's recommended that viewers look for the shooting stars at about midnight, local time, on November 18, in an area well away from the city or street lights.

Taurid meteor shower 2023: When, where & how to see it
➥ https://www.space.com/taurid-meteor-shower

The Taurid Swarm is Upon Us!
➥ https://blogs.nasa.gov/Watch_the_Ski...rm-is-upon-us/

Leonid meteor shower 2023: When, where & how to see it
➥ https://www.space.com/34500-leonid-m...wer-guide.html

Leonid meteor shower: All you need to know in 2023
➥ https://earthsky.org/astronomy-essen...meteor-shower/

Leonids ➥ https://science.nasa.gov/solar-syste...rites/leonids/

[GordMay]

Saturn's system of rings will [likely] completely disappear, due to “ring rain” , over the next 15 to 400 million years; but, over the next two years, we're going to get a preview of this, thanks to a relatively rare celestial event.

Just like Earth, Saturn is tilted on its axis. So, as it orbits around the solar system, it goes through seasons, with the northern hemisphere pointed more towards the Sun for one half of that journey, and the southern hemisphere pointed more towards the Sun for the rest. Since the planet's rings are aligned with Saturn's equator, they follow the same pattern.
So, as we approach March of 2025, the rings are going to gradually fade from our sight [temporarily], over the next fifteen months.

More ➥ https://www.smithsonianmag.com/smart...ary-180983244/

[GordMay]

The bright red star “Betelgeuse” [AKA: ‘Alpha Orionis’], a prominent member of the Orion constellation, is set to be occulted, by the asteroid “Leona”, on December 11.
This occurrence, expected to last no more than 10 seconds, will cause the star to temporarily vanish from sight, a phenomenon visible along a narrow path on Earth.

The path of totality, where the occultation will be observable, stretches across a narrow band, starting near Guadalajara, Mexico, and extends through south Florida, the Bahamas, southern parts of Spain and Italy, through to regions in Greece, Turkey, and central Asia.

Lasting for nearly 18 minutes, the occultation will start at 8:08 p.m. ET and end at 8:26 p.m. ET [December 12 at 01:08:23 UT to 01:26:00 UT].

The Virtual Telescope 2.0 project will livestream the event:
➥ https://www.virtualtelescope.eu/
➥ https://youtu.be/ELQx7SCadM4

[GordMay]

Geminid Meteor Showers:
We get meteor showers, when Earth passes through a trail of leftover debris, shed from a comet or asteroid.
In the case of this month’s Geminids, we are passing through that of an asteroid, called “3200 Phaethon”.
In ideal conditions, under dark skies, there could be upward of 100 to 150 meteors an hour, this week.
The shower will be at its peak, on Wednesday night and early Thursday morning, though you'll likely see some meteors, in the nights before and after.
The meteors will seem to shoot out of the constellation Gemini, but could streak across pretty much any part of the sky. So, if you can find a dark place, with a good view of the sky in any direction, you could get a good view of the Geminids.
The constellation will rise in the east, some time after 7:30 p.m. local time. While it's best to look for meteors when the constellation is overhead, viewers may be able to spot some "earth-grazers" [bright, slow-moving meteors], that cross the sky horizontally, earlier in the evening.

[GordMay]

The Geminid Meteor Shower:
Everything you need to know about the annual Geminid meteor shower.
➥ https://www.planetary.org/articles/y...SAAEgIkK_D_BwE

Video ➥ https://youtu.be/Tw42L5o-7wU

[GordMay]

AP PHOTOS: Moon, asteroids and new rockets topped the world's space news in 2023
➥ https://apnews.com/article/space-yea...9d4a94a441481e




Ring of Fire Eclipse

[GordMay]

A Star Is Born


Stars begin as clumps of dust and gas rotating in a disk. As the matter in the disk coalesces, the gravity at the center of the disk fuses and glows, as a nascent star. We’ve seen such disks around forming stars, in our own galaxy, before, but now astronomers have, for the very first time, detected the rotating disk of material around a very young star, in another galaxy, writes astronomer Phil Plait in his latest column [1], for Scientific American.

The young star, called HH 1177, has jets of matter shooting out from its disk -each spanning 33 light-years, end to end. Astronomers believe that because of the direction the jets are pointed in space, there must be a d isk around the star, feeding the jets. This disk appears more massive and “bulky” than counterparts in the Milky Way, where such dense disks break apart.

Being able to see diverse types of star formation is crucial. “By seeing how the process unfolds under different conditions, we can push the limits of our models to learn how they perform under stress,” writes Plait [1]. “If they remain intact, so, too, does our confidence in their correctness; if they break, then important gaps must linger in our accounts of stellar birth.”

[1] ➥ https://www.scientificamerican.com/a...the-milky-way/


Artist's impression ➘

[GordMay]

Uranus, as seen by Webb’s NIRCam, surrounded by bluish-white rings.

Uranus, the seventh planet from the Sun, still holds plenty of secrets.
We know it’s an ice giant, thought to be mostly (80% or more) icy water, ammonia, and methane, surrounding a rocky core, and that it has skies rich with hydrogen sulfide. It also has a ring system, one that’s far less familiar to us, than the circles around Saturn.

Though Uranus’ rings were imaged before (by Hubble in November 2014 and November 2022 and by Webb in April), the new, gorgeous image adds some detail. For one, this Webb image, taken by the observatory’s Near-Infrared Camera (NIRCam), captures the planet’s faint Zeta ring, the ring closest to the planet.

The close-up above shows nine of the planet’s moons. In clockwise order, starting at 2 o’ clock, they are Rosalind, Puck, Belinda, Desdemona, Cressida, Bianca, Portia, Juliet, and Perdita. Uranus’ moons are sometimes called the “literary moons,” NASA’s website states [1], because they are named for characters in the works of William Shakespeare and Alexander Pope.
Uranus has 27 known moons, according to an ESA release.[2]

[1] Uranus Moons: Overview
➥ https://science.nasa.gov/uranus/moons/

[2] Uranus widefield view (NIRCam compass image)
➥ https://esawebb.org/images/weic2332c/

Bonus:
Potential formation of atmosphere on Uranus' moons
“Moons around Uranus may suddenly develop atmospheres in the spring”
The moons of Uranus may have short-lived atmospheres every time the seasons change. The seasons there are so intense that these tenuous atmospheres, called exospheres, could exist briefly twice every Uranian year before freezing and falling back down to the surface.
More ➥ https://www.newscientist.com/article...in-the-spring/

[belizesailor]

https://youtu.be/tg7EZCM7IlY?si=otIjCcgzj03D4TYh