Any Astronomy Buffs Here?

[OldPhiKap]

(pun intended)

Careful. You do not know the power of the evil that you just unwittingly summoned.

[DevilHorse]

Careful. You do not know the power of the evil that you just unwittingly summoned.

Can it be used to destroy or relieve 'roids?

Larry
DevilHorse

[DevilHorse]

A most interesting video on the orientation of tornadoes. I really never thought much about it before, but evidently people have:
https://www.youtube.com/watch?v=cYsznAuvKLs

Certainly there have been tornado outbreaks, where tornadoes have have been in close proximity. The inverse vorticity makes a lot of sense (conservation of angular momentum). Although this principle doesn't necessarily apply in all cases of tornado production, it would seem that in the case of updrafts, it would be reasonable that pairs of tornadoes could be produced, although cyclonic tornadoes may be sustained more easily as they evolve. [just spitballing]

Larry
DevilHorse

[DevilHorse]

holloweenSaturn1.jpg

All Sirius-ness aside.

Larry
DevilHorse

[PackMan97]

Possible chance to see the Northern lights as far south as TN, VA and NC as a CME is headed our way.

https://www.wral.com/solar-flare-cou...ight/19950636/

[DevilHorse]

Possible chance to see the Northern lights as far south as TN, VA and NC as a CME is headed our way.

https://www.wral.com/solar-flare-cou...ight/19950636/

https://twitter.com/i/status/1454277205815595011
Your close-up Mr. DeMille.

Larry
DevilHorse

[DevilHorse]

Now this is interesting:
https://apod.nasa.gov/apod/ap120524.html

Apparently there is alot of water out there in the solar system. In these times of drought and global warming (and polar ice cap melting) figuring out what resources we have and how to get them where they are needed is a big problem. Interesting to note that there are other sources out (out out) there.

Larry
DevilHorse

[DevilHorse]

Speaking of Telescopes, the following article about the James Webb Telescope crossed my attention today:
https://www.airspacemag.com/airspace...EwMDM0NTQ2NwS2

Next great telescope, yadda yadda..

What caught my attention was that unlike the Hubble Telescope (which orbits the earth, although thanks to Newton's conservation of inertia, always faces the same direction in space), the James Webb would be placed at the L2 Lagrangian Point of the Earth.

Not sure how many of you are familiar with Lagrange, his many contributions to celestial mechanics, or specifically, the Lagrangian Points.
https://solarsystem.nasa.gov/resourc...agrange-point/
The James Webb will take a month to be 'placed' in the L2 Lagrangian point which is along the Sun/Earth access, but the one on the far side of the Earth from the Sun, and about 4 times the distance from the moon (1.5M km or 1M miles about). There are 5 Lagrangian Points between any 2 rotating masses; 3 unstable ones along the line between the masses, and 2 that are off to the sides of the rotating bodies (if you are familiar with the Trojan Asteroids that precede and follow Jupiter in a 60 degree triangle, they are in the 2 off to the side Lagrangian points of the Jupiter/Sun system).

The L2 Lagrangian point of the Earth/Sun system is where the Webb Telescope will find its new home and apparently it is where other satellites will be placed in the future because of desirable properties. Anyone with DirecTV or Dish network knows about GEOsynchronous satellites, which seem to sit in the sky at 22.2 KMile orbits above the equator. The L2 Lagrangian point is yet another stable point, relative to the sun, where the James Webb aperture and electronics can be protected (the Earth shades it from the sun). Some of these points are stable (i.e., the L4 and L5 where the Trojan asteroids are) and the others along the 2 body access are not (you can understand that with a little thought experiment that with 2 rotating bodies, a third body can be in perfect equilibrium between them, or outside of them, along the access as they spin, but the slightest perturbation, and the third body will fly off). This means that any satellite at the L2 Lagrange point will have to occasionally correct its position to stay at the L2 Lagrange point.

You may not have come across Lagrange Points unless you read Astronomy articles, took an intermediate mechanics physics class, or astronomy classes.

Larry
DevilHorse

Glad JD King posted about the James Webb Telescope on the DBR front page. The video was interesting/informative. The only quibble (and it is small) that I had was the pronunciation of Lagrange. Every physicist I've ever heard pronounce it says it like Orange with an accent on the second syllable; Loh-GRANGE with soft Gee's. I'm sure this pronunciation was handed down by word of mouth from people who knew the guy (only 3 centuries ago, and well known), so it isn't open to interpretation!

The video didn't talk much about the G2 point "hiding" behind the moon so sunlight is blocked out, which I thought was pretty cool. They just talked about the equipment blocking out some direct light (also cool).

Anyway, the Hubble produced eye-opening views of the heavens. The James Webb may provide some nifty pictures, but better yet, it might provide information, data, and revelations. There have been no exoplanets found outside of our galaxy. Cool if we find some in Andromeda or the Megallanic Clouds. So much to explore.

Larry
DevilHorse

[-jk]

Glad JD King posted about the James Webb Telescope on the DBR front page. The video was interesting/informative. The only quibble (and it is small) that I had was the pronunciation of Lagrange. Every physicist I've ever heard pronounce it says it like Orange with an accent on the second syllable; Loh-GRANGE with soft Gee's. I'm sure this pronunciation was handed down by word of mouth from people who knew the guy (only 3 centuries ago, and well known), so it isn't open to interpretation!

The video didn't talk much about the G2 point "hiding" behind the moon so sunlight is blocked out, which I thought was pretty cool. They just talked about the equipment blocking out some direct light (also cool).

Anyway, the Hubble produced eye-opening views of the heavens. The James Webb may provide some nifty pictures, but better yet, it might provide information, data, and revelations. There have been no exoplanets found outside of our galaxy. Cool if we find some in Andromeda or the Megallanic Clouds. So much to explore.

Larry
DevilHorse

Not so fast!

https://exoplanets.nasa.gov/news/169...nd-our-galaxy/

"Signs of a planet transiting a star outside of the Milky Way galaxy may have been detected for the first time. This intriguing result, using NASA’s Chandra X-ray Observatory, opens up a new window to search for exoplanets at greater distances than ever before."

-jk

[DevilHorse]

Not so fast!

https://exoplanets.nasa.gov/news/169...nd-our-galaxy/

"Signs of a planet transiting a star outside of the Milky Way galaxy may have been detected for the first time. This intriguing result, using NASA’s Chandra X-ray Observatory, opens up a new window to search for exoplanets at greater distances than ever before."

-jk

How fast was it? 3 hours ?? Obviously not Neutron Star fast. Not rotating. But what else could have passed between that star and us? Interesting case. Would we wait 70 or so years for another event? Assuming Newtonian Mechanics would keep the plane of that Solar System stable so we could observe still observe that occultation. Galaxies rotate. Interesting problem. Nice that Chandra is looking at such things. Updated 12 days ago.

Larry
DevilHorse

[DevilHorse]

We've touched on the subject of light pollution from the many satellites from the Elon Musk Starlink venture.

Many of you have no doubt also seen the movie Gravity with Sandra Bullock, where a collision in space creates a huge amount of space debris that causes a huge calamity for an astronaut crew.

Well yesterday that narrative appeared to be happening for real.
https://www.space.com/space-debris-a...-november-2021
The russians were apparently testing an Anti-Satellite (ASAT) space weapon and attempted to shoot down one of their own satellites. Of course, these things don't get destroyed in a lump and fall to earth; they become a large debris field that orbits the earth in a thousand small, fast moving shards.

The 7 astronauts on the International Space Station had to take cover as it moved through the debris field. But it will not be a one time event unless the ISS is moved to a different orbit to avoid this (now) 'permanent' debris field.

Astro Alexandra provides some additional perspective:
https://twitter.com/i/status/1460374669794713604

Larry
DevilHorse

[DevilHorse]

And, a lunar eclipse coming for North America on Friday early morning:
https://pbs.twimg.com/media/FDW7M0NV...png&name=small

Larry
DevilHorse

[-jk]

And, a lunar eclipse coming for North America on Friday early morning:
https://pbs.twimg.com/media/FDW7M0NV...png&name=small

Larry
DevilHorse

Thanks. I think I won't stay up for this one!

-jk

[OldPhiKap]

Thanks. I think I won't stay up for this one!

-jk

Yeah, why don’t they schedule lunar eclipses in the daytime when it would be more convenient?

[wavedukefan70s]

My kid is jonesing for a telescope .he jas a older model like 30 yrs old plus the astronomical binoculars.
I purchased this today for his birthday so hopefully it will do the job. It needed to be mobile .
Celestron - StarSense Explorer 130mm Newtonian Reflector Telescope -
Anyone ever used this model?

[CameronBornAndBred]

My kid is jonesing for a telescope .he jas a older model like 30 yrs old plus the astronomical binoculars.
I purchased this today for his birthday so hopefully it will do the job. It needed to be mobile .
Celestron - StarSense Explorer 130mm Newtonian Reflector Telescope -
Anyone ever used this model?

I have a Celestron Astromaster 130, and have enjoyed it lots. For most of my viewing, I use my larger 8" dobsonian, but the 130 has lots of benefits that I have no doubt that your kid will enjoy. Primarily, the one you got is way easier to transport due to size and weight. The mirror is nice enough size that you can really enjoy planetary viewing, and it looks like the phone app will be helpful in finding targets. It will still take patience finding what you are looking at since it isn't computer controlled, but he will get used to it. It also looks like the mount and tripod are pretty user friendly. My Astromaster has an equatorial mount, which while having lots of advantages, can also be headache inducing. (A big reason why I love my dobsonian.)

He's going to have fun!

[wavedukefan70s]

I have a Celestron Astromaster 130, and have enjoyed it lots. For most of my viewing, I use my larger 8" dobsonian, but the 130 has lots of benefits that I have no doubt that your kid will enjoy. Primarily, the one you got is way easier to transport due to size and weight. The mirror is nice enough size that you can really enjoy planetary viewing, and it looks like the phone app will be helpful in finding targets. It will still take patience finding what you are looking at since it isn't computer controlled, but he will get used to it. It also looks like the mount and tripod are pretty user friendly. My Astromaster has an equatorial mount, which while having lots of advantages, can also be headache inducing. (A big reason why I love my dobsonian.)

He's going to have fun!

Thanks for the input .

[DevilHorse]

Thanks. I think I won't stay up for this one!

-jk

Most interesting. My initial thought was to get up just a wee bit early.

BTW, eclipses tend to cluster as you (might) know. Solar eclipses (rarer and more geographically local on earth events) are sometimes preceded by (or followed by) lunar eclipses; and sometimes a second lunar eclipse in a month (not this time I'm afraid). This is obviously because the moon's revolution around the earth each 27 days 8 hour, and its' position relative to the sun, allows the ecliptic (earth/moon/sun plane) cross every ~14 days.

It just so happens that in 2 weeks there will be a solar eclipse on Dec 4, 2021.

The next solar eclipse will be a total solar eclipse on Dec. 4, 2021. It will be the only total solar eclipse of the year and the last total solar eclipse until 2023. Totality will be visible from Antarctica; skywatchers in South Africa, Namibia, the southern tip of South America and some islands in the South Atlantic will be able to see at least a partial solar eclipse.

Larry
DevilHorse

[budwom]

Yeah, why don’t they schedule lunar eclipses in the daytime when it would be more convenient?

Your thinking is right up there with Ali G, who asked Buzz Aldrin why astronauts couldn't travel to the sun in Winter when it is, of course, cooler. Great minds!

[camion]

Your thinking is right up there with Ali G, who asked Buzz Aldrin why astronauts couldn't travel to the sun in Winter when it is, of course, cooler. Great minds!

Don't have to wait til winter. Just go at night.*





*Old, old joke. Older than dirt's grandfather.