# The sun is not yet 20 years old **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [August 24, 2023, 3:51pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040 "2023-08-24T15:51:19Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Mijin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mijin/32/9369_2.png) [@Mijin](https://boards.straightdope.com/u/Mijin)\ **Post date:** [August 24, 2023, 3:51pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/1 "2023-08-24T15:51:19Z")
…measured in galactic orbits, that is. If I am measuring _my_ age in solar orbits, it should measure its age in _galactic_ orbits. A single orbit takes 230 million years. Measured against this benchmark, Mr High and Mighty “billions of years old” plasma furnace is still some punk college-kid. On this scaling: The sun’s birth (formation from a collapsing cloud of gas and dust) took about **4 hours** It then went through a difficult period of having intense solar winds for **5 days** (protostar) It has stayed in pretty much it’s current form for the following **19 years** (main sequence) But it will start to expand over the next **23 years** (red giant) It will then _massively_ expand for **6 months** , followed by a **month** in which its size changes frequently. Finally it will exist as a white dwarf. The scaling breaks down here, as white dwarves will likely take trillions of years to fizzle out, so even scaled, we’re talking hundreds of thousands of years. ---
**Author:** ![Mollie\_Magill](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mollie_magill/32/20882_2.png) [@Mollie\_Magill](https://boards.straightdope.com/u/Mollie_Magill)\ **Post date:** [August 24, 2023, 4:05pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/2 "2023-08-24T16:05:45Z")
> [@Mijin](#): > > …measured in galactic orbits, that is. > > If I am measuring _my_ age in solar orbits, it should measure its age in _galactic_ orbits. > A single orbit takes 230 million years. Measured against this benchmark, Mr High and Mighty “billions of years old” plasma furnace is still some punk college-kid. Am I the only person who thought this was some new CT that the world actually began in 2003? ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [August 24, 2023, 8:19pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/3 "2023-08-24T20:19:38Z")
> [@Mollie\_Magill](#): > > Am I the only person No. I do like the OP and this idea, but this was one of those threads where I totally did NOT get what I expected when I unwrapped the package. ---
**Author:** ![Jasmine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jasmine/32/2964_2.png) [@Jasmine](https://boards.straightdope.com/u/Jasmine)\ **Post date:** [August 24, 2023, 8:33pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/4 "2023-08-24T20:33:50Z")
> [@Mijin](#): > > If I am measuring _my_ age in solar orbits, it should measure its age in _galactic_ orbits. Why? The only thing that would accomplish is to create an annoying second step by sending people to Google to find out how old the sun is in “real” years. Not only that, it is a totally relativistic system. Two stars of identical mass are born at the same time, but one is half way towards the center of the galaxy, and the other is in the outskirts of the galaxy. In your system, one would be twice as “old” as the other simply because it was circling the galactic core twice as fast. ---
**Author:** ![Mijin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mijin/32/9369_2.png) [@Mijin](https://boards.straightdope.com/u/Mijin)\ **Post date:** [August 24, 2023, 8:35pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/5 "2023-08-24T20:35:27Z")
It was just meant to be a bit of fun for MPSIMS. I just found it interesting that the sun’s age is on human scales when counted in galactic orbits. Never mind. ---
**Author:** ![Jasmine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jasmine/32/2964_2.png) [@Jasmine](https://boards.straightdope.com/u/Jasmine)\ **Post date:** [August 24, 2023, 8:38pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/6 "2023-08-24T20:38:15Z")
> [@Mijin](#): > > Never mind. Now I feel guilty. 😳 ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [August 24, 2023, 8:47pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/7 "2023-08-24T20:47:48Z")
> [@Mijin](#): > > …measured in galactic orbits, that is. Which puts it somewhere in the vicinity of 521,775,000 microfortnights old, or about 140 dog years. ---
**Author:** ![Happy\_Lendervedder](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/happy_lendervedder/32/8488_2.png) [@Happy\_Lendervedder](https://boards.straightdope.com/u/Happy_Lendervedder)\ **Post date:** [August 24, 2023, 8:59pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/8 "2023-08-24T20:59:29Z")
Almost 664 Galactic Scaramuccis. Not too shabby for an arrogant ball of gas. ---
**Author:** ![Mollie\_Magill](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mollie_magill/32/20882_2.png) [@Mollie\_Magill](https://boards.straightdope.com/u/Mollie_Magill)\ **Post date:** [August 24, 2023, 9:02pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/9 "2023-08-24T21:02:12Z")
> [@Mijin](#): > > It was just meant to be a bit of fun for MPSIMS. > > I just found it interesting that the sun’s age is on human scales when counted in galactic orbits. > > Never mind. I thought it was a fun idea. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [August 24, 2023, 9:08pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/10 "2023-08-24T21:08:10Z")
> [@Happy\_Lendervedder](#): > > Almost 664 Galactic Scaramuccis. Not too shabby for an arrogant ball of gas. Speaking of arrogant bags of gas … Scaramucci certainly qualified. As did / does his erstwhile boss. > [@Mollie\_Magill](#): > > I thought it was a fun idea. Me too. Heck, we already talk about Mars years that are 1.88 Earth years, or Jupiter years that are 11.86 Earth years. Sun years fits right in with that. ---
**Author:** ![Pardel-Lux](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pardel-lux/32/20182_2.png) [@Pardel-Lux](https://boards.straightdope.com/u/Pardel-Lux)\ **Post date:** [August 24, 2023, 9:17pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/11 "2023-08-24T21:17:45Z")
I was intrigued by the title but not expecting a CT at all, quickly thought it was a neat idea when I read the explanation, and found the breakdown (formation → protostar → main sequence → etc) was well developed. **Mijin** , you did well in my opinion. Now I wonder whether this thread can give some interesting angles to the original idea apart from the criticism already expressed. I guess saying that based on my experience the sun should soon run out of spots at this age is not really constructive. I’ll try to think of something better and more relevant. But yeah, I was a punk too at that age and had a lot of fun. I wish the Sun many more happy years! ---
**Author:** ![Digger11](https://avatars.discourse-cdn.com/v4/letter/d/838e76/32.png) [@Digger11](https://boards.straightdope.com/u/Digger11)\ **Post date:** [August 24, 2023, 9:34pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/12 "2023-08-24T21:34:23Z")
> [@Jasmine](#): > > Why? The only thing that would accomplish is to create an annoying second step by sending people to Google to find out how old the sun is in “real” years. Not only that, it is a totally relativistic system. Two stars of identical mass are born at the same time, but one is half way towards the center of the galaxy, and the other is in the outskirts of the galaxy. In your system, one would be twice as “old” as the other simply because it was circling the galactic core twice as fast. That’s precisely what will happen if we ever establish colonies on Mars, etc. People will have to decide on some format for “translating” their ages. ---
**Author:** ![Mijin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mijin/32/9369_2.png) [@Mijin](https://boards.straightdope.com/u/Mijin)\ **Post date:** [August 24, 2023, 9:41pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/13 "2023-08-24T21:41:20Z")
> [@Jasmine](#): > > Now I feel guilty. 😳 Nah it’s all good. Just typical humor fail by me. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [August 24, 2023, 10:18pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/14 "2023-08-24T22:18:04Z")
> [@Jasmine](#): > > Not only that, it is a totally relativistic system. Two stars of identical mass are born at the same time, but one is half way towards the center of the galaxy, and the other is in the outskirts of the galaxy. In your system, one would be twice as “old” as the other simply because it was circling the galactic core twice as fast. Yup, and Podkayne was nine years old when folks started telling her it was about time to think about getting married. > [@engineer\_comp\_geek](#): > > Which puts it somewhere in the vicinity of 521,775,000 microfortnights old, or about 140 dog years. Are you Sirius? ---
**Author:** ![Gatopescado](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gatopescado/32/5711_2.png) [@Gatopescado](https://boards.straightdope.com/u/Gatopescado)\ **Post date:** [August 24, 2023, 11:07pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/15 "2023-08-24T23:07:43Z")
I will expect daily updates. ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [August 25, 2023, 4:39am UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/16 "2023-08-25T04:39:02Z")
> [@Jasmine](#): > > Two stars of identical mass are born at the same time, but one is half way towards the center of the galaxy, and the other is in the outskirts of the galaxy. In your system, one would be twice as “old” as the other simply because it was circling the galactic core twice as fast. Galaxies don’t rotate like that, because of the influence of their dark matter halo. Unlike planets orbiting a star, a galaxy rotates almost like a solid object, with the rotation period largely independent of distance from the center. This breaks down somewhat in the central bulge, but out in the disk part, the [rotation curve](https://en.wikipedia.org/wiki/Galaxy_rotation_curve) is nearly flat. ---
**Author:** ![alovem](https://avatars.discourse-cdn.com/v4/letter/a/b38774/32.png) [@alovem](https://boards.straightdope.com/u/alovem)\ **Post date:** [August 25, 2023, 6:31am UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/17 "2023-08-25T06:31:47Z")
> [@LSLGuy](#): > > I do like the OP and this idea, but this was one of those threads where I totally did NOT get what I expected when I unwrapped the package. I got it just from the thread title, before reading the OP. ---
**Author:** ![blondebear](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/blondebear/32/1022_2.png) [@blondebear](https://boards.straightdope.com/u/blondebear)\ **Post date:** [August 25, 2023, 2:08pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/18 "2023-08-25T14:08:04Z")
It’s not the years, it’s the mileage. ---
**Author:** ![Coriolanus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/coriolanus/32/18769_2.png) [@Coriolanus](https://boards.straightdope.com/u/Coriolanus)\ **Post date:** [August 25, 2023, 9:09pm UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/19 "2023-08-25T21:09:39Z")
> Some 5 billion years from now, there will be a last perfect day on Earth… then the sun will begin to die, life will be extinguished, the oceans will boil and evaporate away. > -Carl Sagan Sucks to be 40+ ---
**Author:** ![Larry\_Borgia](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/larry_borgia/32/156_2.png) [@Larry\_Borgia](https://boards.straightdope.com/u/Larry_Borgia)\ **Post date:** [August 26, 2023, 12:16am UTC](https://boards.straightdope.com/t/the-sun-is-not-yet-20-years-old/989040/20 "2023-08-26T00:16:14Z")
I liked it.