Questions tagged [data-analysis]
Analysis of data is a process of inspecting, cleaning, transforming, and modeling data with the goal of discovering useful information, suggesting conclusions, and supporting decision making.
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Request for Information on how to make a FITS Image
I know that at the end of the Receivers in Radio Telescopes, after the final Amplifier the analog signal will be given to the ADC. Now this ADC converts the analog signal into a stream of binary bits. ...
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Using data from the Fine Guidance System (HST)
Has anyone been able to successfully use data from the Hubble Space Telescope's fine guidance system in order to create light curves?
I found a bunch of older papers that reference this instrument, ...
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cross-matched SDSS-WISE catalog
Please where can I find cross-matched SDSS and WISE dataset for a machine learning project?
(Galaxy-star-qso classification task)
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Computing error bar for vertex of parabola-fit lightcurve
I have a long-term lightcurve for my source, to which I have used orthogonal distance regression to fit a quadratic model [expected flux]=a[year]²+b[year]+c.
Part of our data analysis includes finding ...
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Parameters erroneously measured to be negative
I am interested in physical quantities which are strictly non-negative, but which, due to errors, may realistically be estimated as negative. The only examples I can think of are interstellar ...
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Astronomers need Data Analytics or Data Science?
I am aiming to do my masters in Astronomy, and I would prefer it to be on the data side of it. I am looking to skill-up and am confused if I should take up Data Analytics courses or Data Science ...
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plotting light curve for x ray data
how can I plot the light curve for Chandra X-ray data? I want to extract the counts within the specified energy range from the light curve.
e.g., I have to extract the counts within the energy range ...
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Tiling the sky with astropy-healpix
I have a bunch of files containing sources with galactic l and b values. What I want is to redistribute the sources such that each new file contain sources that fall within 15 degrees of a central l,b ...
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Basics of Tracklet-less Heliocentric Orbit Recovery (THOR) - simple breakdown of how it works?
The New York Times's April 30, 2024 Killer Asteroid Hunters Spot 27,500 Overlooked Space Rocks begins:
With the help of Google Cloud, scientists churned through hundreds of thousands of images of the ...
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How can I use SDSS archive to find the radial velocities of binary stars?
I need to plot a radial velocity curve of a given binary star system, and I think that the SDSS apogee survey has what I need, but I havent had any luck finding anything on it. It this the right tool ...
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Which distortion polynomial does the astrometry.net platesolver use?
I am investigating whether it is feasible to predict the distortion of a widefield image platesolved by Astrometry.net and. its documentation says it uses the Simple Image Polynomial to estimate ...
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How could a Dyson Swarm be detected?
My understanding is that a completed Dyson Sphere would be detectable because we would see a star that seemed to produce only infra-red light, and much less than would be expected from an object of ...
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How can I join as contributor to open source code on GitHub? [closed]
I want to join as a contributor, e.g., making pull or merge requests on GitHub, in an existent open source astronomy project. How do I start? What's the typical scenario? Writing directly to the ...
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How to determine semiamplitude from Julian Date data?
How could I determine semiamplitude from these data for NGC300 X-1 without fitting, only with data of phase and JD? This is a common problem for exoplanets, X-ray binaries and other general binary ...
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On building a compatible pipeline for astrometry using both Gaia or Vera-Rubin's data
As the title states, I'm considering building a pipeline for astrometry to analyze Gaia and Vera Rubin's data.
As, being honest, I have little experience with astrometry, I'm not sure if this is (or ...
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What are These Strange Data Spikes in my Catalog Data?
This question has been completely rewritten as I have found a bit more information and been helped enough to hopefully ask this question better.
Hi everyone. I am an undergraduate pursuing an honors ...
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How to Determine Absolute Magnitude of a Galaxy using HST FITS Image
I'm attempting my first serious research project but due to... various circumstances, I am going to mostly be solving problems like this on my own with minimal outside help.
As for the actual problem, ...
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Could an hypothetical hidden black hole companion to the sun be revealed by proper motion data?
If the Sun were in a binary star system with a black hole companion, the Sun would be orbiting the black hole, and this should be reflected in a change in the observed proper motion of nearby stars.
...
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Moon's libration from Mathematica data
Wolfram Mathematica provides "TransitTime" option (for the Moon in particular).
Knowing this time moment, you can get the position of the moon at upper culmination
(for example, for each day ...
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CMB maps analysis (Planck, ESA, FITS)
I wanted to analyze Planck mission FITS files and was wondering about the parameters. So the map uses color coding for temperature-based anisotropies right? So the maximum angular resolution is ...
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Formation of spacecraft instrumentation [closed]
List of spacecraft instruments are selected to meet a mission's science goals.
Let's take New Horizons as an example and study the composition of Pluto's atmosphere, the shape and geological ...
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Calculating intensity of moonlight per unit area
I have a photodiode that can measure intensity in picowatt to milliwatt range.
I have a telescope of 5 inch diameter. I want to calculate the intensity of moonlight received by this area? This will ...
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Radio Astronomy Data Handling (Filtering What One Needs)
Suppose we have some radio astronomy data for some specific moment (not a time series). Can we, using some computer program, filter out and get, say, only the data (EM radiation), whose sources are at ...
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Sloan Digital Sky Survey - Obtaining Spectral and Photometric Datasets
I am working on a soft computing (fuzzy logic), genetic algorithm, explainable AI (XAI) classification system for astronomical objects from the Sloan Digital Sky Survey. The dataset I am currently ...
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How can I compute reasonable errors on my Gaussian fits to the observed strong optical lines of interest?
I'm fitting Gaussians to optical lines spanning from H-beta to Sulfur using Astropy's Gaussian (https://docs.astropy.org/en/latest/api/astropy.modeling.functional_models.Gaussian1D.html) model with a ...
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Bad syntax for region SIMPLE -- dmextract CIAO 4.15
I am trying to perform a radial profile analysis using Chandra's CIAO 4.15 dmextract function but keep getting the following error: "bad syntax for region SIMPLE". I cannot find any relevant ...
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How to get star position from the Gaia data set?
I’m trying to recreate the Milky Way as a particle system inside Houdini, and I wanted to explore using the Gaia data as a starting point.
I’ve downloaded an example source file from the data set but ...
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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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ds9 configuration issue
I'm trying to use DS9 for X-ray image analysis. Before that I have to configure it for use, I need to click on option using web proxy.
Beside use internal web browser checkbox there should be another ...
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What are examples of spatio-temporal data sets such that subjects are observed only once and are, thus, indexed in time only once?
What are examples of spatio-temporal data sets such that subjects are observed only once and are, thus, indexed in time only once?
Here's a hypothetical example in the ecology realm: consider a tree's ...
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How to construct optimal Wiener Filter?
I am trying to construct a Wiener Filter, to filter the ratio of the peak from the cross-correlation function, between a galaxy spectra and a template spectra, with the peak of the auto-correlation ...
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What am I doing wrong in this ppxf application?
I am trying to derive the kinematics of a galaxy spectra. To test my results I want to implement the Penalized Pixel Fitting method. For the galaxy spectrum I use a central line with sufficient S/N. I ...
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How can someone take narrowband data from an OSC narrowband filter
To those who aren’t aware, an OSC narrowband filter is a filter with multiple band passes, for different emission lines. These can include a combination of Hα, Hβ, OIII, SII, and other emission lines. ...
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Where can I get raw photos of planets clicked by HST, Voyager 1 and 2, Cassini for Saturn and Galileo for Jupiter?
I intend to process RAW images of planets clicked by HST,Voyager 1 and 2, Cassini and Gallileo spacecrafts using a few softwares.
I am in search of where I can get these raw images from.
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Convert image from Jy/sr to Jy/pix
I want to convert the units of an image from Jy/sr (Janskys per steradian) to Jy/pix and I know the pixel scale in arcsec. The way I do this, in python, is the following:
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Solar-winds: public NOAA data
I was searching for interesting data from space recently, and stumbled onto https://www.swpc.noaa.gov/.
The long and short is that they offer some interesting solar wind data
Of particular interest to ...
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Finding the uncertainty in period for String-Length Minimization calculation
I wrote a Python script that calculates the period of an unevenly sampled data set using the String-Length Minimization method.
You can read about that method here: A period-finding method for sparse ...
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What's a good example of published astronomy pipeline coding libraries
I am a software engineer and I am preparing a presentation to aspiring astronomy PhDs on how to use best-practice software engineering when publishing code (such as include documentation, modular ...
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Do astronomical datasets exist that receive duplicates or are there multiple datasets that contain the same entities (stars)?
I am currently doing my PhD in computer science, and I have almost no astronomical knowledge. I am currently researching on duplicate detection in databases (so detection of multiple entries referring ...
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2D Galaxy Spectrum taken by long-slit-spectrograph
I have the 2D data (shape(1125,2058) taken by a long slit spectrograph, which looks as follows:
The y-axis corresponds to the distance from the center, where the center is at the most bright green ...
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How did asteroid (7482) 1994 PC1 get its "face"? Is it reconstructed from optical or radar imaging, or something else?
(Image sources linked below)
NPR's March 10, 2023 Newly found asteroid has a 'very small chance' of hitting Earth, NASA says includes an image of what looks like a computer reconstructed 3D surface of ...
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How has the resolution of astronomical spectrographs improved over time?
Is there something like a Moore's law for spectral resolution? Maybe a chart from which one could extrapolate?
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Best resource for exoplanet statistics?
While the number of detected exoplanets is still low, is there a model that, considering the number and duration of made observations, and the fact that (non)detections depend on orbital plane ...
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How does one actually fold a light curve?
I'm studying the variable stars (periodic variables with brightness changes repeating over time), and to examine the shape of the light curve it is useful to fold the data points at this period and ...
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Reduced chi square value
I am currently plotting a continuum of observed data. I need to check the effectiveness of the fitted continuum with the reduced chi-square method. Ideally, should the reduced chi-square value ...
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What is the most common activity of astronomers in the JWST? [closed]
I am no astronomer. I am a computer scientist.
I recently read this article: JWST has changed the speed of discovery, for better or for worse - Astronomers are working at a furious pace to analyze and ...
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How can we make sure that it is physically the same source when we do cross matching?
When we go through multiple astronomy catalogs, we often do Cross-matching. We compare the position parameters $(\alpha, \delta)$ of different sources (galaxies, quasars, etc.) in the equatorial ...
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What determines how accurate a particular method is at finding the period between Lomb-Scargle and String Length Minimization?
I've been using the Lomb-Scargle and String Length Minimization methods to find the periods of various astronomical objects with unevenly spaced data. I wanted to see if I could find any patterns ...
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Database for distant stars
I'm looking for a database of stars that lists as many of the known stars as possible. Ideally, I'd like it to have information on the radius of the stars, the distance from the earth and the ...
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How does one convert between Modified Julian Date (MJD) and a standard (mm/dd/yr, hr:mm:ss)
I looked online and couldn't see an actual formula or anything, so I figured I'd ask here.
If I had an MJD like the following: 59145.6678
How would I convert that to a month, day, and year with the ...
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