Dear students,

this site contains some information on and sample data used in the practical labs.

In a preliminary meeting we will go over the lab procedure again and make sure that all necessary software is running properly. To try out some of the analyses, this site provides some sample data similar to the ones you will acquire and configuration files.  

Prior to the observations, suitable objects have to be determined. They need to be visible on the night sky during the observation time, should be sufficiently bright (the minimal brightness is dependend on the instrument and the observation conditions), and should be in a part of the sky that is observable by the set-up.
The following links might be helpful in finding the right objects.

Planetarium software Stellarium (Link), Stellarium-Wiki (Link)

Planetarium software Cartes du Ciel (Link)

Sky calendar Calsky (Link)

Messier objects (Link)

Objekt selection in the course Astrophysik (Summary, Presentation)

In the course of the practical labs a variety of robotic telescopes will be introduced that can be operated via internet. The use is free of charge and makes it possible to take first astro images. One exception is Slooh. To use their robotic telescopes a fee-based account is necessary.

The use of Slooh will be explained and coordinated by the supervisors.

NASA MicroObservatory (Link), Instructions (Link)

Slooh (Link)

Bradford Robotic Telescope (Link)

Image processing

DeepSkyStacker (Link), Short instructions (pdf)

MicroObservatory Image (Link)

PixInsight, Trial License (Link), Short instructions (pdf)

Photometry and Astrometry

Astrometrica (Link)

Using astronomy it is possible to determine certain characteristics of celestial objects. Some important properties are the position and the orbit of the object. In the course of the lab the softwares Astrometrica and find_orb will be used to compute the orbit data of minor planets. 

Astrometrica (Link)

Analysis

find_Orb (Link)

Orbit Plot (file)

Data

Configuration file Astrometrica (file)

Sample data of Pallas (file)

(Please note that there are more data than necessary for the determination. You can choose some to practice astronomy and get a feel for how many are necessary.)

Important! A tutorial with instructions (file).

There are different methods to create color images (L-RGB - Images) using data acquired with different color filters. For the two methods presented here, the data have to be stacked first. A free software used for that is DeepSkyStacker.

The first method (used in the seminar of the lecture Astrophysics) is based on PixInsight. PixInsight is a pay to use software. However, you can receive a trial licence on the PixInsight homepage. Receiving the licence after applying for it might take a couple of days.

The second method creates RGB color images with the help of DeepSkyStacker and the software Fitswork. You can also use Photoshop to add the luminescence channel to produce a L-RGB image.

1) With PixInsight

DeepSkyStacker (Link), short instructions (pdf)

PixInsight, trial license (Link), short instructions (pdf)

2) With Fitswork and Photoshop

DeepSkyStacker (Link)

Fitswork (Link)

Adobe Photoshop

Video instructions

LRGB_short_instructions.pdf

LRGB_DeepSkyStacker.mp4

LRGB_Fitswork.mp4

LRGB_Photoshop.mp4

Spectroscopy can be used to find the intesities of different wavelength of the light captured by a telescope. The university has a quite simple spectometer for student use to capture the spectum of objects. 

To analyse these spectrums a freeware calles Visual Spec can be used.

The example is a spectrum of Jupiter. It can be used to find the elements that make up its atmosphere. Basically, the light emitted by the sun is reflected from Jupiter's surface towards the Earth. This means that the spectrum that we measured passed Jupiter's atmosphere twice and then the Earth atmosphere. Each time certain wavelengh light is absorbed and can be seen with a decreased intensity in the spectrum. These lines can be used to find the elements of the atmospheres.

To analyse the spectrum we also need a calibration image of iod taken with the same settings.

Visual Spec (file)

Example data Jupiter (file) calibration data (file)

Instructions for Visual Spec (file) [German but with pictures]

Displaying data and images in astronomy often requires special programs. The commonly used data format .FITS cannot be opened with a standard image manipulation program. Nevertheless, there are a range of free programs that work with .FITS files.

DS9 - a powerful visualization package (Link)

FITS Liberator - a small but versatile program by ESA/ESO/NASA (Link)

MicroObservatory Image - to work with MicroObservatory data (Link)