Questions tagged [hr-diagram]
Use this tag for questions regarding the Hertzsprung-Russell diagram.
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Using Gaia Passbands with L_nu coordinates
I am trying to find the coordinates of my bundles of gas on the gaia ($G, G_{bp}-G_{rp}$) hr diagram. I have its spectrum in $\nu L_\nu$ coordinates. Thus far, my attempts have mainly been to ...
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Unusual amount of white dwarfs in star clusters in my analysis
I'm trying to plot H-R Diagrams of open clusters using data from Gaia DR3. My workflow is something like this:
Plot apparent magnitude vs log(distance) in pc. An overdensity would indicate the ...
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How do nuJ(nu) units work?
I'm working with (Nublado) Cloudy, which is essentially a spectral modelling tool for stellar matter. Using the software, I model my own stellar object and obtain its continuum.
According to Hazy, ...
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How do you use Gaia Passbands to find Gbp-Grp Coordinates?
I've never used Gaia passbands, or any type of passbands before for that matter. I have a theoretical model of a stellar object, and its corresponding emissions as a function of wavelength. I'd like ...
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Difference in HR diagram clusters
I was wondering what the difference in an HR-diagram would be between an open and globular cluster.
I've trying to compare both by looking up diagrams online, but can't find diagrams with same axes. I ...
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Is there a general way to plot the evolutionary track of a star on HR diagram?
HR diagrams for stars are available on the internet and it is also easy to plot this for thousands of stars from their absolute magnitude and color index values (obtainable from any catalog). However, ...
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What would the HR diagram look like if the axes were scaled linearly instead of logarithmically?
The Hertzsprung-Russell diagram typically has its axes scaled logarithmically, and with good reason. The hottest stars are about 20 times as hot as the coldest ones (at least at the surface), and the ...
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Which star has the faintest absolute magnitude (largest magnitude) yet is still visible with the naked eye from Earth (either hemisphere)?
I am thinking about the Bright Star Catalogue and how it is not a good representation of a typical population of stars. The Bright Star Catalogue includes all the visible stars from Earth when viewing ...
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Why do blue horizontal branch stars turn downwards on the HR diagram as opposed to red horizontal branch stars which remain fairly constant?
Horizontal branch stars (HB) burn helium at their cores. Red horizontal branch (RHB) stars experience an increase in temperature while their radii decrease so their luminosity remains somewhat ...
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What is the wiggle in the AGB branch?
In many HR diagrams, the asymptotic giant branch includes a wiggle. I thought that these are thermal pulses, but now I realise there are many thermal pulses, and I find only one wiggle. The wiggle ...
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Is a branch on HR diagram a line formed by stars in the same evolutionary phase, or the evolutionary track of an individual star?
Here is a HR diagram from Wikipedia, in the well-known form:
Here is another one from the Stellar evolution article:
I know that when stars leave the main sequence, they go to the giant branch ...
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Graphing the evolution of stars on an HR diagram with timesteps
I have found countless images regarding the evolution of stars, plotted on an HR Diagram, like so (found on Wikipedia):
Although this displays the time in each stage, it does not include any points ...
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HR diagram x-axis (color) and redshift?
I've read several articles and watched some videos on the HR diagram, but no-one seems to mention the effect of redshift on the color of a star. Is there some calibration step that needs to be applied ...
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Is there a formula to calculate any star mass from Luminosity, Radius, and/or Temperature (K)? [duplicate]
I know there is the Mass-Luminosity relationship, but I am wondering if there is a more accurate formula I can use based on the data points I have generated:
Absolute Magnitude (based on class and ...
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How does the stellar evolution for low and intermediate mass stars differ?
I'm trying to understand stellar evolutionary tracks for different masses. So far I have the general understanding from a cloud of gas and dust to a white dwarf, neutron star or black hole.
What I don'...
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