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How many supernova explode every year?

badastronomy.beehiiv.com

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Re: How many supernova explode every year?

#121

Two questions come to mind. 1) When was the last supernova observed in our own galaxy? 2) How close would one have to be to be observed with the naked eye?

1604. One could say we are overdue. I’m not sure about dust or other obstacles blocking it, but based on brightness alone a supernova in our galaxy should be visible with naked eye.

Re: How many supernova explode every year?

#122

Earlier quoted context omitted.

A star "lasts" about 10 billion years, so you'd expect about 1 in 10 billion stars to 'die' each year, but only a tiny proportion (the very largest) go supernova. Numbers are huge. Even tiny ratios mean something like 10-100 stars go supernova every single second somewhere in the universe. Sounds a lot? Only about 1 star per galaxy goes supernova per century. A lot of galaxies. Mindblowing.

what's the rate of Type Ia supernovas? Higher I would guess? (n>=2-aries are common and medium mass main sequence stars are common, though it takes them a while to get to white dwarf)

1/2 as common. https://astrobites.org/2022/04/16/template-post-9/#:~:text=T...

Re: How many supernova explode every year?

#123

First off, dont look at the outer wilds discussion on here, just play the game. Second - they didnt say how many letters we need to encode all of the observable supernova in a given year! So 100 billion galaxies, 1 per year per galaxy, we have around 1 billion to encode. Sorry two edits this moring, first one was right. due to math without coffee. 1e9/26^6 is about 3, 1e9/26^7 is less than one. So we might see 'SN205…

I bought Outer Wilds based on recommendations like yours and I found it kind of boring. The world is mostly empty and the repetitiveness wore me down. I didn't finish it. It's a great looking game though and the first hour or two I had a blast.

Same here. I found the controls to be frustrating and the game-play loop to be kinda dull. The story on the other hand, is very good. I get that the game-play is meant to illicit certain feelings, but it just didn't do it for me. I did enjoy reading a synopsis of the story on the wiki though.

Re: How many supernova explode every year?

#124

That's one of my favourite hints in Outer Wilds. You will see a Supernova. Not with a fancy telescope, it's visible to the naked eye, and if you watch the sky you'll see another soon enough. You can see this right at the start, and unlike the random direction of the probe launch you don't need any game lore to, if you're smart enough, put two and two together.

[flagged]

I recommend deleting this post.

Re: How many supernova explode every year?

#125

Earlier quoted context omitted.

I bought Outer Wilds based on recommendations like yours and I found it kind of boring. The world is mostly empty and the repetitiveness wore me down. I didn't finish it. It's a great looking game though and the first hour or two I had a blast.

Same here. I found the controls to be frustrating and the game-play loop to be kinda dull. The story on the other hand, is very good. I get that the game-play is meant to illicit certain feelings, but it just didn't do it for me. I did enjoy reading a synopsis of the story on the wiki though.

Question for you and commenter above, do you play games with controls similar to Outer Wilds often? Do you play many games in general? I've seen this comment a few times and I'm curious why this is such a common talking point. I thought the controls were very intuitive, so I'm curious if it's a familiarity issue or something else.

Re: How many supernova explode every year?

#126

Earlier quoted context omitted.

Not only that, it happened a long long time ago. I'm no astronomer; would that be more or less supernovae?

Indeed. They didn't say it happened an "int" time ago. They didn't even say a "long" time ago. They said a "long long" time. I'd have to pull up a copy of the C standard to be sure, but even if the units of "time" are plank times, I suspect the implications could easily be that the story occurs before the big bang.

I suspect you're thinking of a double (floating point). A long long is only a 64 bit integer.

2^64 planck times is 9.9e-25 seconds. Planck times are really tiny.

2^64 nanoseconds is 584 years.

Re: How many supernova explode every year?

#127

Earlier quoted context omitted.

Same here. I found the controls to be frustrating and the game-play loop to be kinda dull. The story on the other hand, is very good. I get that the game-play is meant to illicit certain feelings, but it just didn't do it for me. I did enjoy reading a synopsis of the story on the wiki though.

Question for you and commenter above, do you play games with controls similar to Outer Wilds often? Do you play many games in general? I've seen this comment a few times and I'm curious why this is such a common talking point. I thought the controls were very intuitive, so I'm curious if it's a familiarity issue or something else.

I don't recall having any problems with the controls. As long as I can invert the y axis, I'm a happy camper.

Re: How many supernova explode every year?

#128

Earlier quoted context omitted.

Same here. I found the controls to be frustrating and the game-play loop to be kinda dull. The story on the other hand, is very good. I get that the game-play is meant to illicit certain feelings, but it just didn't do it for me. I did enjoy reading a synopsis of the story on the wiki though.

Question for you and commenter above, do you play games with controls similar to Outer Wilds often? Do you play many games in general? I've seen this comment a few times and I'm curious why this is such a common talking point. I thought the controls were very intuitive, so I'm curious if it's a familiarity issue or something else.

I don't play 3D games; I bought Outer Wilds for the experience, was unable to understand the controls. I tried really hard, but had to quit.

Re: How many supernova explode every year?

#129
Near the top he shows two photos of the Cartwheel galaxy, one from 2014 and one from 2021 with the caption:

> Can you spot Supernova 2021 axdf?

Are you supposed to be able to spot the supernova?

All I've noticed is a couple of small stars that disappear in the latter photo, but this mostly seems to be because it's more blurry.

Re: How many supernova explode every year?

#130

Near the top he shows two photos of the Cartwheel galaxy, one from 2014 and one from 2021 with the caption: > Can you spot Supernova 2021 axdf? Are you supposed to be able to spot the supernova? All I've noticed is a couple of small stars that disappear in the latter photo, but this mostly seems to be because it's more blurry.

Use the cross-eye trick to superimpose the two pictures, then it becomes quickly noticeable as it will appear to blink.
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