6 upvotes, 2 direct replies (showing 2)
View submission: Ask Anything Wednesday - Physics, Astronomy, Earth and Planetary Science
Well direction obviously is just the direction we point in but distance is usual determined either using "standard candles".
The most commonly used standard candles in astronomy are Cepheid Variable stars and RR Lyrae stars. In both cases, the absolute magnitude of the star can be determined from its variability period.
Type Ia supernovae are also normally classed as standard candles, but in reality they are more standardisible candles since they do not all have the same peak brightness. However, the differences in their peak luminosities are correlated with how quickly the light curve declines after maximum light via the luminosity-decline rate relation, and they can be made into standard candles by correcting for this effect. <
Since the star has a known brightness we can look at it's apparent brightness to determine how much distance is required for the light to get to the level we observe.
Also can use parallax which is taking a picture from two places usually we take pictures on opposite sides of earth orbit and by doing some geometry we can figure out the distance from us to the object in question
Comment by dark_enough_to_dance at 20/07/2022 at 20:32 UTC
3 upvotes, 1 direct replies
Thanks for that solid answer. I didn't know that there might be many ways to find the solution.
Comment by ThoughtCenter87 at 20/07/2022 at 21:34 UTC
1 upvotes, 1 direct replies
What is a candle in this context?