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Re:Stars may collide in a “red nova” in 2022 by jcrites on Sunday January 08, 2017 @06:38AM (#13349304)
Fascinating. It will be wondrous to see if it occurs.

It also reminds me of a premise in one of my favorite science fiction novels, Diaspora by Greg Egan. In the story, the characters are monitoring the orbit of a binary star system. The orbit is decaying and a collision is expected at some point. However, soon the characters realize that the orbit is decaying far faster than expected. Extrapolating, and discovering new properties of stellar physics, the characters realize that the stars are mysteriously losing angular momentum, which will lead to them spiraling downward into a prompt collision that will produce supernova-scale energies. The binary star is in Earth's neighborhood, so this will put all life on the planet at risk. It will be brighter than the sun in daylight.

There's a great deal more to the plot than that (I don't want to spoil it) -- that's just the event that kicks things off. It's a great book and I'd highly encourage all sci-fi fans to read it. Hopefully nothing like this happens in real life, and we are confident and correct about the amount of energy that will be released :-)

While thinking about these topics, it is difficult not to ponder the frailty of life, and the astonishing vastness and expanse of the cosmos. How easy it would be for a star to snuff out all life on a world.

Re:Stars may collide in a “red nova” in 2022 by david-given on Sunday January 08, 2017 @07:11AM (#13349387)
Seconded --- it's a great book. Egan has an amazing talent for off-handedly mentioning and then casting aside multiple mind-expanding ideas per chapter that other authors would expand into a complete novel.

Non-spoiler: I believe this book features the biggest sculpture in fiction.

(Currently reading _Incandescence_.)

Re:Stars may collide in a “red nova” in 2022 by pavel_lishin on Sunday January 08, 2017 @03:45PM (#13351898)
It's been awhile since I've read it; I'm going to try and ask this question in a spoiler-free way: are you talking about the thing they end up 'chasing' through the 4-6-4-6 (or arguably 3-5-3-5, etc)?
Re:Stars may collide in a “red nova” in 2022 by netcraft on Sunday January 08, 2017 @05:07PM (#13352338)
thats it. Another vote for it being a great book - lots of amazing ideas.
Re:Stars may collide in a “red nova” in 2022 by DrScump on Monday January 09, 2017 @05:12PM (#13360287)

  Fascinating. It will be wondrous to see if it occurs.
It's 1800 light-years away. It already happened a long time ago. Unless it didn't.

  mysteriously losing angular momentum
Did it discuss a scenario how that would be possible (lack of conservation of total angular momentum)?
Re:Stars may collide in a “red nova” in 2022 by perseusprime11 on Sunday January 08, 2017 @12:56PM (#13350952)
Can anyone recommend a good telescope that wont break my bank? I would love to get into watching celestial events. Any recommendations?
Re:Stars may collide in a “red nova” in 2022 by MPSimmons on Sunday January 08, 2017 @02:46PM (#13351549)
There are tons of good advice threads on the internet for this, because it's actually a really hard decision.

I looked into it a year ago or so, and pretty much universally, the advice was, "start with really good binoculars, because even relatively expensive beginner telescopes aren't all that much better, and it's more important to understand what you're looking at than to see it well".

Then, by the time you know whether or not you're going to be "into it", you'll know if you want to spend a few grand on a Dobsonian (which isn't necessarily the best answer, but is a good example).

Re:Stars may collide in a “red nova” in 2022 by hengheng on Sunday January 08, 2017 @03:03PM (#13351652)
A bit of meta discussion that usually isn't mentioned in those advice threads:

There's a big divide between visual telescopes that you can use to see things 'live' with your naked eye, and observing telescopes that are mainly used for photography.

The visual ones are more fun, used e.g. for the Messier rally where you try to spot all Messier objects in one night. Let's say it'll be a 12" f/4 to f/10 mirror, giving you suboptimal magnification but nice and bright images. Easy handholdability, difficult to attach a camera, imprecise tracking if any at all. Telescope usually fits in your trunk and is made to be assembled each night.

The telescopes that are used for photography are more akin to classical observatories. Guiding motors are now mandatory, usually you'll have a stationary place (concrete foundation and all) to have your scope perfectly aligned. You'll use it almost exclusively computer-operated, timing the images across different color channels and working only remotely. This way it is actually possible to do research even as an amateur ... but also to capture deep sky objects like nebulae in their full color detail.

There are hybrids, but those are quite niche, and usually not best bang-for-buck. Personally I'm considering to get myself a tele lens or two, and a cheap outdated digital camera body along with it. That way I'll only need a tracking mount, and I'll have enough to dip my feet into the water.

Re:Stars may collide in a “red nova” in 2022 by DrScump on Monday January 09, 2017 @05:05PM (#13360250)
There are lots of good homebuilt options. The site of the late John Dobson, founder of San Francisco Sidewalk Astronomers, has some resources:

http://www.sfsidewalkastronomers.org/index.php?page=telescop...

Re:Stars may collide in a “red nova” in 2022 by ISL on Tuesday January 10, 2017 @04:08AM (#13363616)
Make friends with a friendly local astronomy club. It'll be free, you'll meet nice people, you'll get to use their glass, and you'll get as much advice as you want.

Or, as MPSimmons suggests, get some wonderful binoculars (in a pinch, the ones with the largest objective lenses you can find), a comfortable clear moonless night, and a blanket to lay on.

Mostly, though, just go look.

Re:Stars may collide in a “red nova” in 2022 by Achshar on Sunday January 08, 2017 @01:49PM (#13351225)
If a "nearby" supernova is happening, I don't think looking at it through a telescope is a good idea. Don't quote me on it though.
Re:Stars may collide in a “red nova” in 2022 by schoen on Sunday January 08, 2017 @02:47PM (#13351554)
That doesn't feel right to me (though it all depends on how nearby is nearby).

https://en.wikipedia.org/wiki/SN_1987A

"Its brightness peaked in May with an apparent magnitude of about 3"

(a few million times fainter than the full Moon)

Re:Stars may collide in a “red nova” in 2022 by kordless on Sunday January 08, 2017 @05:12PM (#13352367)
That nova was in another galaxy, albeit a close one. The one we're talking about here is about 1-2K light years away.
Re:Stars may collide in a “red nova” in 2022 by schoen on Sunday January 08, 2017 @10:56PM (#13353888)
Great point, thanks!

Wikipedia says KIC 9832227 is "almost 1800 light years away" while SN 1987a is "167885 ly" from us. There should be an inverse square relationship for the intensity of light reaching us by our distance from the object, so light from this nova should be

  You have: (167885 ly / 1800 ly)^2
  You want: 
          Definition: 8699.1893
times brighter than that from SN 1987a due to proximity (which would still be much dimmer than the full Moon). However, the expected nova is also far dimmer to begin with:

https://en.wikipedia.org/wiki/Luminous_red_nova#Characterist...

"The luminosity of the explosion occurring in luminous red novae is between that of a supernova (which is brighter) and a nova (dimmer)."

So I'm still going to say "safe to observe with a telescope".