Unusual Redness of Betelgeuse: A Mystery in the Night Sky?

  • Thread starter Thread starter scupydog
  • Start date Start date
Click For Summary

Discussion Overview

The discussion centers on the perceived unusual redness of the star Betelgeuse as observed by participants, exploring potential reasons for this observation, including atmospheric conditions and the star's characteristics. The scope includes observational astronomy and the behavior of variable stars.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants note that Betelgeuse is inherently a red star due to its cooler surface temperature.
  • Others suggest that the increased redness observed could be attributed to atmospheric conditions or light pollution rather than an actual change in the star.
  • One participant speculates that Betelgeuse might be evolving, given its high mass and relatively young age in astronomical terms.
  • There are mentions of Betelgeuse's variability, with references to its historical brightness changes and pulsation cycles.
  • Some participants express uncertainty about the visibility of changes in Betelgeuse's color over short time frames, emphasizing the difficulty in predicting stellar events like supernovae.
  • One participant shares a personal anecdote about observing a red moon, suggesting that terrestrial factors can influence color perception in celestial observations.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the cause of the observed redness, with multiple competing views regarding atmospheric effects versus potential changes in the star itself. The discussion remains unresolved regarding the specific reasons for the perceived increase in redness.

Contextual Notes

Participants acknowledge that the variability of Betelgeuse's brightness and color may not be easily noticeable on a night-to-night basis, and there are references to its pulsation cycle and historical brightness data that may influence observations.

scupydog
Messages
101
Reaction score
0
Hello all I'm here in the uk just lookin at Betelgeuse and for some reason it looks redder tonight has anyone any idea why? thx
 
Last edited:
Astronomy news on Phys.org
scupydog said:
Hello all I'm here in the uk just lookin at Betelgeuse and for some reason it looks red tonight has anyone any idea why? thx

Betelgeuse looks red every night...
 
Betelgeuse is a red star... it always looks red because it's surface temp is quite cool.

When Betelgeuse supernova's, we will know it. It will be brighter than a full moon due to it's relatively close proximity with Earth.

Editing because I just noticed you said 'redder'. Betelgeuse will likely get more red over time, but that's not a change we'd be able to observe with the naked eye. If it's looking redder to you, I'd assume it's just atmospheric conditions where you're at or possibly light pollution in your location. Or, your mind is just playing tricks on you.
 
Guys, I think he means that it's redder than usual.
It might be evolving?
It's only a few million years old, but it does evolve faster than others because of it's high mass. But I have to admit, to be seen from 640 light years away, it is pretty bright. :)
 
Debyule said:
Betelgeuse is a red star... it always looks red because it's surface temp is quite cool.

When Betelgeuse supernova's, we will know it. It will be brighter than a full moon due to it's relatively close proximity with Earth.

Editing because I just noticed you said 'redder'. Betelgeuse will likely get more red over time, but that's not a change we'd be able to observe with the naked eye. If it's looking redder to you, I'd assume it's just atmospheric conditions where you're at or possibly light pollution in your location. Or, your mind is just playing tricks on you.

Right, it's far more probably that the increased redness is a function of atmospheric conditions or some terrestrial source rather than any actual change in the star. It's notoriously difficult to predict when a star will nova, and when it does, things usually happen very fast, so there's no way of knowing "oh, Betelgeuse is going to nova in the next 48 hours, keep your eyes peeled."

Heck, could've already done it and we wouldn't know yet.
 
scupydog said:
Hello all I'm here in the uk just lookin at Betelgeuse and for some reason it looks redder tonight has anyone any idea why? thx

I don't think in a human life anyone can see a red giant becoming redder just a bit. You saw it redder that night probably because of the atmosphere. I myself one everning saw quite a red moon and it turned out there was a road construction several miles away.
 
Last edited:
I think we are safe. The rotational axis is not pointed in our direction so we need not fear a gamma burst. It will. however, be very, very bright when it goes supernova [which is very likely in the next few million years]
 
Last edited:
scupydog said:
Hello all I'm here in the uk just lookin at Betelgeuse and for some reason it looks redder tonight has anyone any idea why? thx


Not tonight, but in 27 days from now on 3 am Eastern time. Don't miss it!
 
I'm not sure if this is why you saw it as redded than usual but http://www.aavso.org/vstar/vsots/1200.shtml"
 
Last edited by a moderator:
  • #10
variable star...


Observations by the observers of the AAVSO indicate that Betelgeuse probably reached magnitude 0.2 in 1933 and again in 1942.

At minimum brightness, as in 1927 and 1941, the magnitude may drop below 1.2. Betelgeuse is a semi-regular pulsating red super-giant. It is believed to be at least the size of the orbit of Mars and at maximum diameter may possibly equal the orbit of Jupiter. The star is one of the largest known; spectroscopic studies show that the diameter of the star may vary by about 60% during the whole cycle, a difference considerably larger than the radius of the Earth's orbit!
[/Color]
Reference:
http://www.aavso.org/vstar/vsots/1200.shtml"
 
Last edited by a moderator:
  • #11
chemisttree said:
I'm not sure if this is why you saw it as redded than usual but http://www.aavso.org/vstar/vsots/1200.shtml"

But you are not likely to notice a night to night difference, as it varies from a magnitude of 0.3 to 1.2 with a peak to peak cycle of 14 years or so. It is somewhat of a slacker when compared to a star like Mira, which can go from a magnitude of 10.1 to 2 in 100 days, actually going from being not visible to the naked eye to easily noticeable to the naked eye. (It then takes 200 days to dim back down to 10.1)
 
Last edited by a moderator:
  • #12
Thank you for all your replies, its just that it seemed a lot redder than usual that night and i was watching for a few hours its been overcast since so not had a chance to see it recenctly, thanks again all.
 

Similar threads

  • · Replies 60 ·
3
Replies
60
Views
13K
  • · Replies 8 ·
Replies
8
Views
19K
  • · Replies 35 ·
2
Replies
35
Views
34K
  • · Replies 6 ·
Replies
6
Views
5K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 7 ·
Replies
7
Views
4K
  • · Replies 12 ·
Replies
12
Views
5K
  • · Replies 12 ·
Replies
12
Views
3K
  • · Replies 5 ·
Replies
5
Views
5K
  • · Replies 5 ·
Replies
5
Views
2K