The Night Sky

Betelgeuse may go supernova, was once in the top 10 brightest stars but now doesn't even make the top 20.
If it does it would be visible in the daytime, which would be amazing.

Betelgeuse may go supernova, was once in the top 10 brightest starts but now doesn't even make the top 20.
If it does it would be visible in the daytime, which would be amazing.

One can only hope that it does this in our lifetime. Stellar lifelines are a bit more protracted than ours...

[SIZE=7]Waiting for Betelgeuse: what's up with the tempestuous star?[/SIZE]
by David Dickinson, [Universe Today]('https://www.universetoday.com/')
[IMG alt="Waiting for betelgeuse: what’s up with the tempestuous star?"]https://scx1.b-cdn.net/csz/news/800/2019/waitingforbe.jpg[/IMG]
Have you noticed that Orion the Hunter—one of the most iconic and familiar of the wintertime constellations—is looking a little… different as of late? The culprit is its upper shoulder star Alpha Orionis, aka Betelgeuse, which is looking markedly faint, the faintest it has been for the 21st century.

When will this nearby [supernova]('https://phys.org/tags/supernova/') candidate pop, and what would look like if it did?

The story starts, as all good astronomy and space stories seem to, on Friday night going into a holiday weekend. We started seeing discussion on Betelgeuse trending on social media on the evening of Friday, December 20th, and dug down to the source of the excitement: a December 8th paper, "[The Fainting of the Nearby Red Supergiant Betelgeuse]('http://www.astronomerstelegram.org/?read=13341')," by researchers at Villanova University. Light curve estimates courtesy of the American Association of Variable Star Observers (AAVSO) verified the assertion that the star had, indeed, faded about one magnitude, or a little over one-half from its usual magnitude +0.5 to +1.5. Noticing the sky was clear, we headed up to our parking garage rooftop observing site in downtown Norfolk, Virginia, to take a look. Betelgeuse was, indeed, noticeably fainter, about a shade dimmer than nearby +1 magnitude Aldebaran.

Now, a change in one magnitude isn't unusual for a [variable star]('https://phys.org/tags/variable+star/') such as Betelgeuse. But such a large dip always gives the astronomical community pause. A [red giant star]('https://phys.org/tags/red+giant+star/') 12 times as massive as the sun and about 700 [light years]('https://phys.org/tags/light+years/') distant, the variability of red-orange Betelgeuse was first noted by astronomer Sir John Herschel in 1836. Physically, the star is currently bloated out to a radius of perhaps eight astronomical units (AU). If you plopped it down in the center of our solar system, Betelgeuse might extend all the way out past the orbit of Jupiter.

[IMG alt="Waiting for betelgeuse: what’s up with the tempestuous star?"]https://scx1.b-cdn.net/csz/news/800/2019/1-waitingforbe.jpg[/IMG]
Our (puny) host star, versus the neighbors, including Betelgeuse. Credit: Dave Dickinson

This fact also allowed astronomers to use the first crude optical interferometric measurements from the 2.5 meter telescope at Mount Wilson Observatory to measure Betelgeuse's physical diameter of 50 milliarcseconds. In the late 1980s, astronomers used an emerging technique of aperture masking interferometry to obtain the first direct 'image' of Betelgeuse.

Betelgeuse is always worth keeping an eye on, as it's one of the closest candidates in our galaxy for a nearby supernova. We see supernovae frequently in distant galaxies, but such an event has not been witnessed in our galaxy in the telescopic era: Kepler's Star in 1604 in the constellation Ophiuchus was the last supernova observed in the Milky Way, though a supernova in the nearby Large Magellanic Cloud put on a good show in 1987. A red giant like Betelgeuse lives fast and dies young, exhausting its supply of hydrogen fuel in just under 10 million years. The star is destined to undergo a core implosion and massive collapse and rebound as a Type II supernova. Such an explosion could occur 100,000 years from now… or tonight.

Is the fading act a prelude to a truly spectacular show, or a false alarm? Astronomers are unsure, but a supernova event just 700-odd light-years away would be an unrepresented opportunity to study one up close. Not only would every optical telescope get trained on the exploding star, but assets such as the Laser Interferometry Gravitational Wave Observatory (LIGO) could detect gravitational waves from a nearby supernova, and neutrino observatories such as Ice Cube buried in the Antarctic ice could detect the event, as well.
[IMG alt="Waiting for betelgeuse: what’s up with the tempestuous star?"]https://scx1.b-cdn.net/csz/news/800/2019/2-waitingforbe.jpg[/IMG]

A pulsating Betelgeuse in the ultraviolet. Credit: NASA/HST

Fortunately for us, we're safely out of the 50 light-year 'kill zone' for receiving any inbound lethal radiation from Betelgeuse: A supernova would simply be a scientifically interesting event, and put on a good show. Ancient supernovae may have had a hand in the evolution of life on Earth, and a recent study suggests that one might even have forced early humans to walk upright.

What would a supernova in Orion look like? Well, using the last supernova in the Large Magellanic Cloud (also a Type IIb event) as a guide, we calculate that when it does blow, Betelgeuse would shine at magnitude -10. That's 16 times fainter than a full moon, but 100 times brighter than Venus, making it easily visible in the daytime sky. A Betelgeuse-gone-supernova would also easily cast noticeable nighttime shadows.
[IMG alt="Waiting for betelgeuse: what’s up with the tempestuous star?"]https://scx1.b-cdn.net/csz/news/800/2019/3-waitingforbe.jpg[/IMG]
Nearby supernova candidates out to 1,000 light-years. Credit: Dave Dickinson

But see the ongoing fading event for yourself. Betelgeuse is easy to find in December, rising to the east at dusk. In fact, northern hemisphere winter is the very best time for the star to blow, as it's roughly opposite to the sun, and would dominate the night sky. Summer would be the worst time, as it would tease us from beyond the far side with the sun in the daytime sky.
[IMG alt="Waiting for betelgeuse: what’s up with the tempestuous star?"]https://scx1.b-cdn.net/csz/news/800/2019/4-waitingforbe.jpg[/IMG]
Betelgeuse, versus the stars of the Winter Hexagon with annotated magnitudes (note: this was taken prior to the current dimming event). Credit: Steve Brown.

What's next? Well, expect Betelgeuse to brighten again in early 2020… though if it rebounds into negative magnitude territory past Rigel and Sirius, well, then things could get really exciting.

For now though, we're in a wait-and-see-mode for any New Year's Eve fireworks from Betelgeuse. Such an occurrence would be bittersweet: We would be extraordinarily lucky to see Betelgeuse go supernova in our lifetime… but familiar Orion the Hunter would never look the same again.

Another good discussion about Betelgeuse's brightness fluctuations...

[[SIZE=5]Betelgeuse, Betelgeuse, Betelgeuse[/SIZE]]('https://apod.nasa.gov/apod/ap200101.html')

Another good discussion about Betelgeuse's brightness fluctuations...

If it were to go supernova we would be one blessed generation to be able to see something like that.

So far Hale-Bopp in 1997 has been my celestial highlight, Kohoutek was a dud when I was a kid.
For some reason I don't remember Hyakutake as well as Hale-Bopp.

Well because we pretty much have nothing else to do & no where to go.
So why not?

[URL unfurl="true"]https://www.yahoo.com/lifestyle/attention-stargazers-weekend-best-time-153000462.html[/URL]

Get ready for the "PINK MOON" tomorrow night!! No, it's not a Victoria's Secret special, just named pink because phlox is blooming in some areas of the country, sure as heck isn't happening here, mine are still brown...

It WILL be the brightest moon of the year. It is a Super Moon because the moon is in perigee, closest to earth. It also means the tides will be extreme so get your clam rakes ready!!

Get ready for the "PINK MOON" tomorrow night!! No, it's not a Victoria's Secret special, just named pink because phlox is blooming in some areas of the country, sure as heck isn't happening here, mine are still brown...

It WILL be the brightest moon of the year. It is a Super Moon because the moon is in perigee, closest to earth. It also means the tides will be extreme so get your clam rakes ready!!

NO !! Stay home !!!!! You don't want to be near all those guys on the flats. :)

NO !! Stay home !!!!! You don't want to be near all those guys on the flats. :)

First, the only other guy on my flats was YOU!! :ROFLMAO: :ROFLMAO: :ROFLMAO:

Second, the Maine clam diggers are in real trouble. Those soft shell, steamers for our LI brotheren, are almost exclusively sold to restaurants, so the market has tanked with the closures. Add to that, unlike hard shell clams, steamers don't last long out of water so storage isn't an option. Basically prices are horrible and many folks aren't digging...

Makes sense to me. Now if we could just get the lobstermen to stay home .:)
I'm not even going to bring up Bluefin. :(

Amazing compilation

[URL unfurl="true"]https://thewildchild.co.za/photographer-captures-worlds-clearest-picture-of-the-moon-ever-taken/[/URL]

[URL unfurl="true"]http://www.physics-astronomy.com/2020/04/set-your-alarm-jupiter-venus-and-moon.html?m=1&fbclid=IwAR0w86Y-P76y9GRiWlBc4wMN2pEko3ppHtl3-E79MrnDH5LGJGogZrUc8hQ[/URL]

Earth and the Moon as seen from Saturn. We're that little dot and the Moon is the tiny dot...

Another cool one it's NOT a faint star and the crescent moon, but a crescent Venus and the planet Mercury!!

Real good streak going. You've heard of Green Flashes of the sun, right? It is cool when you actually see one, as I have on a very few occasions. However, what about Green Flashes of the Moon, Venus and Mercury??? Hell, I've only seen Mercury once!!!

Comet NEOWISE from the ISS...

Dang, this comet is an Internet Star. Hopefully it will clear up at dusk next week so I espy it...

Finally got a glimpse of Comet NEOWISE (Near-Earth Object Wide-field Infrared Survey Explorer satellite) this evening. It's NO Comet Hale-Bopp that magnificent one we saw in 1997, but it's better than Comet Halley back in 1986 (telescope only) or Comet Kohoutek in 1976 (invisible). I could make it out with naked eye, but it was better in binoculars so you could catch it's long tail. I took some crude photos and included one below, but the really suck.

With an orbit that takes 6800 years, it's interesting to think what was happening the last time humans saw this comet. In Mesopotamia, the Sumerians were just starting to write with a proto-cuneiform system. In Europe, the Minoan culture was kicking off and in Egypt, the first pharaoh hadn't been seated yet.

If you want to see it, now is the time. Get yourself in an area with a clear view of the NW horizon and bring you binoculars. Here's a picture to help you find it:

And here's my crappy photo, taken with my cell phone. The comet is circled in the tiny white line

More Comet NEOWISE Porn, this time from Bavaria with the Trifecta of the comet, a meteor and the iconic Castle Neuswchanstein.

Jupiter & Saturn high inda sky right now, check it out... cellie...

.

Mars is in meridian right now, look up... cellie...