astronomy

问题 i'm new to Swift, and now i'm trying to build sky map app like the application "star chart". i already got a sky map image from NASA and cover it on SCNsphere, also already set camera node in the center of this sphere to make it looks like 360 degrees. Furthermore, i used accelerator to check what direction the camera is looking at. i know that the sky map like “star chart” doesn't need internet to update data. so now the biggest problem is that i don't know how to correct the position of my

问题 Hoping this question is not too vague, or asking for too much. Essentially I am analyzing large amounts of spectra, and wanting to create one large webpage that contains these spectra rather than looking at individual spectra. Attached is an example of what the end result should look like. Each individual spectra on there is pulled from a massive library. It has been a long time since I have coded, so this is still a learning experience. I have managed to create a webpage, and pull forward a

问题 I am trying to find out the longitude of ascending/descending moon nodes using Skyfield but unable to find any reference in documentation. Is it possible? Also do any of the JPL Files provide this data already? 回答1: It is easy to at least find them relative to the J2000 ecliptic — which might be fine for dates far from the year 2000 as well, since I think that only the definition of ecliptic longitude changes with the passing years, but not latitude (which is what the nodes care about)? In

问题 I'm trying to build a model of the upcoming total solar eclipse on Aug. 21 in THREE.js. Using NASA's SPICE toolkit, I was able to get extremely accurate rectangular geometric coordinates for the Sun and the Moon for each minute of the day, using the J2000 Earth-centered inertial frame. After setting a DirectionalLight at the location of the Sun and pointing it at Earth, I was able to create a shadow that traverses the earth at the correct time and along the correct map, according to NASA. The

问题 I worked with Sloan Digital Sky Survey (SDSS) data, and got a final data product of this file. The first column is of wLength (wavlength) and second is of flux . Storing the zeros in zero_F variable zero_F = find(a==0) , I removed them from both columns using wLength(zero_F)=[]; and flux(zero_F)=[]; . I want to plot wLength vs flux , flux is dependent on wLength but wLength contains values which are non-unique. How can I get indices of non-unique values in data so that I can remove the

问题 Based on the Healpy/Healpix documentation, I cannot understand the relationship between one pixel in a sky map (which is some measured value) and the spherical harmonic coefficients produced by Healpy's healpy.sphtfunc.map2alm function, which computes an array of the a_lm coefficients for a given map. (This question also applies to anafast.) My understanding is that a given pixel should correspond to a spherical harmonic coefficient. However, it doesn't. At all. Take a map with nside = 8 .

问题 For a school project a friend of mine and I are currently trying to program a simulation of our solar system. The platform we use is Glowscript and we're working with VPython. We have programmed our whole solar system already with all its planets, the sun and the forces between them. Now we're trying to add some extras and one of them is a menu in which the user can select a planet. In our code the selected object (a planet or the sun which are defined in the code) will be labeled as the

问题 I am struggling to find the best way of removing unwanted targets from a list of coordinates. My coordinates (Ra, Dec) are formed using astropy.coordinates.SkyCoord but I have a large number of un-observable targets that are too low in declination, so what I want to do is sort through my list and remove all targets with a declination lower than -10 degrees for example (as my telescope is in the northern hemisphere). This is the line of my code that produces the list, its called radecs for

问题 I am attempting to produce a beam on a healpix map, using healpy. For starters, I would like to be able to produce a 2D gaussian in a mollweide projection, but I really don't know where to begin. I can define a 2D gaussian: import numpy as np def gaussian_2D(x,y,mu_x=0.,mu_y=0.,sig_x=1.,sig_y=1.): return np.exp(-0.5*(((x-mu_x) / sig_x)**2 + ((y-mu_y) / sig_y)**2)) such that I can build up a 3D X, Y, Z space like: delta = 0.025 x = np.arange(-4, 4, delta) y = np.arange(-4, 4, delta) X, Y = np

问题 I'm nearly finished with this program, but I can't get the output quite how I want it. Here is the code: import numpy as np filename = (raw_input("Which file are we loading? ")) header = input("How many header lines? ") # Input variables for column numbers and limiting factors pcol = input("What column number is parallax in? ") vcol = input("What column number is Vmag (or other limiting mag) in? ") pmcol = input("What column number does proper motion begin in (Mu/PA or MuRa MuDec format) ")