Unanswered Questions
114 questions with no upvoted or accepted answers
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What could be observed with LOFAR in 230 MHz - 10.0 MHz wavelength?
Nuclear astrophysics greatly interests me and i was wondering if there is something that could be observed with the LOFAR project in this wavelength that would benefit the field?
Also some general ...
- 30.7k
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How to convert Log(g) vs T_eff to y vs (v-y)?
I have a plot in Log(g) vs T_eff coordinates from my stellar evolution model. The parameters of the model are M=0.8 M_solar, [Fe/H]=-1.19, Y=0.245. I want to convert it to the y vs (v-y) coordinates (...
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Why does D4000 affect stellar age?
From my understanding D4000 is a ratio between the 'flux densities between 4050 and 4250 Angstroms and that between 3750 and 3950 Angstrom', from Poggianti et al (1997). However I do not understand ...
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How does one interpret the definition of "accretion" in galaxy formation?
I am having trouble finding a solidifying definition of accretion when it comes to galaxy formation models and galaxy evolutions. Where as, in the context of satellite galaxies, dwarf galaxies, or ...
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magnetic shield for spacecraft outside of Earths shield
I'd like to know if it's possible to create a strong enough onboard magnetic field, similar to Earths' that would protect deep space spacecrafts from the solar wind?
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DESDM COADD image access
I'm just starting a project to analyze some of the images obtained from the Dark Energy Survey (DES), and I'd like to get some of the COADD images from the SV data.
For example, this paper: https://...
- 111
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Help With Transit Radio Telescope Data Analysis
My high school teacher and I recently built a 10 ft. mesh dish transit radio telescope. In order to compete this year at Nationals for our science fair, we came up with the idea of using a bluetooth ...
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Stars as nozzles; how important is thermodynamics and the de Laval nozzle equation for understanding the speed of the solar wind vs distance?
Seeing What determines the speed of a star's solar wind? I'm having flashbacks from undergraduate days where the professor started their lecture on solar wind by writing something that they called ...
- 30.7k
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How to compute the perihelion precession of Earth's orbit?
I want to simulate the perihelion precession of Earth. I tried searching other posts in stack exchange as well relating this question but may be it's my fault that I couldn't understand their answers....
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Project Analog Hypothetical Planet
For my story Project Analog, I was wondering if a hypothetical planet (Let's call it Suria). It has the same size and conditions as Earth with the same axis, tilt, and rotation, as well as one moon. ...
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Deriving Faber-Jackson Relation from Milgrom's Law
I am reading Famaey & McGaugh 2011, a review paper on Modified Newtonian Dynamics. My question concerns bullet 3 in Sec 5.2, where the authors try to explain how Faber-Jackson Relation can be ...
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Flux from the Sun on the Earth using the Stefan-Boltzmann law
What is wrong with this computation, plase? I am getting the result of 4291.65 W m^{-2} instead of 1361 W m^{-2}. Thank you very much
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Consistent values for density of galaxies between degree squared and steradian
I have a table of densities of galaxies :
Expected number density of galaxies for photometric survey per unit area and redshift intervals, $\mathrm{d} N / \mathrm{d} \Omega \mathrm{d} z\left[\mathrm{...
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How to plot different curves in the same polar cordinates in matplotlib?
I tried to plot the paths of particle of different sizes in the same polar coordinate using the code given below using matplotlib. somewhat like this:
Instead I got this plot:
while the path for ...
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Crop a FITS file in shape of another
I have a FITS file, let us say file A. I have another FITS file, file B. File B has a smaller footprint than file A. I want to crop file A in shape of file B. How do I go about doing that?
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