<p>This is more of a question of human perception, than astronomy. I was going to answer your question with this: "One, it just needs to be close to Earth." But, I decided it wasn't THAT funny. Anyway, stars are essentially point sources as far as our eyes are concerned. Typical visual resolution is about 0.02° or 0.0003 radians. Assuming from horizon to horizon is 180° (or π radians) that calculates out to roughly 10,000 stars. I'd probably increase that by 50% or 100% to be sure. You do understand that you can't line stars up side by side, I hope. There's no need, its about the angular distance, not absolute distance between them, that matters. They can be light years apart as long as they appear to be within about 1 arcminute of one another, our eyes will see them as a single object - subject to the psychological aspects of keeping color and apparent magnitude roughly uniform as well.</p>

CC BY-SA 3.0
2016-07-19T04:17:28.413Z
This was going to be my answer, but I have been beat!
Tanenthor
CC BY-SA 3.0
2016-07-19T04:40:33.273Z
I'll vote +1 for "funny" because you were nice enough to continue and leave a remarkably well thought out answer as well! Speaking of pixels, just a factoid for comparison, if a phone has  400 pixes/inch and it's 16 inches from my face, that's about half, or 0.00016 radians and considered below visual resolution.
uhoh
CC BY-SA 3.0
2016-07-19T01:18:41.190Z
2016-07-19T01:18:41.190Z
Li Zhi
<p>I was talking with a friend about how slowly the star field changes (based on the speed that we are moving through the galaxy) and I started to wonder about a star's visible size.  They are basically the pixels that make up our sky.  This made me wonder, how many stars (let's use the north star as a reference.) would it take (lined up side by side) to draw line that appeared solid across the middle of the sky, perpendicular to the horizon which appeared solid?</p>

CC BY-SA 3.0
2016-07-19T04:44:39.437Z
I never would have thought there would be a way to ask "how many pixels does the sky have?" and get away with it, but you pulled it off!
uhoh
CC BY-SA 3.0
2016-07-19T06:28:38.567Z
The milky way is pretty much solid, just not a thin line but a wider band (and not of uniform luminosity).
orion
<star>
How many stars would it take to draw a line across the middle of the sky that appeared solid?
Hoytman
# How many stars would it take to draw a line across the middle of the sky that appeared solid?

(Asked by: username_0 on 2016-07-19)

I was talking with a friend about how slowly the star field changes (based on the speed that we are moving through the galaxy) and I started to wonder about a star's visible size. They are basically the pixels that make up our sky. This made me wonder, how many stars (let's use the north star as a reference.) would it take (lined up side by side) to draw line that appeared solid across the middle of the sky, perpendicular to the horizon which appeared solid?

**Tags:** star
> **Comments:**
> **username_1**: I never would have thought there would be a way to ask "how many pixels does the sky have?" and get away with it, but you pulled it off!  
> **username_2**: The milky way is pretty much solid, just not a thin line but a wider band (and not of uniform luminosity).  

---

## 1 answers

### Answer by username_3 on 2016-07-19. Score: 8 | Accepted answer

This is more of a question of human perception, than astronomy. I was going to answer your question with this: "One, it just needs to be close to Earth." But, I decided it wasn't THAT funny. Anyway, stars are essentially point sources as far as our eyes are concerned. Typical visual resolution is about 0.02° or 0.0003 radians. Assuming from horizon to horizon is 180° (or π radians) that calculates out to roughly 10,000 stars. I'd probably increase that by 50% or 100% to be sure. You do understand that you can't line stars up side by side, I hope. There's no need, its about the angular distance, not absolute distance between them, that matters. They can be light years apart as long as they appear to be within about 1 arcminute of one another, our eyes will see them as a single object - subject to the psychological aspects of keeping color and apparent magnitude roughly uniform as well.

> **Comments:**
> **username_4**: This was going to be my answer, but I have been beat!  
> **username_1**: I'll vote +1 for "funny" because you were nice enough to continue and leave a remarkably well thought out answer as well! Speaking of pixels, just a factoid for comparison, if a phone has  400 pixes/inch and it's 16 inches from my face, that's about half, or 0.00016 radians and considered below visual resolution.  

---

