Preliminary work for Lecture 5.2. (coordinates & time)

1. Use a sky map / star chart to familiarise yourself with some of the constellations that can be seen in the night sky at this time of the year, for example Orion, Cassiopeia (in Finnish "Kassiopeia") or Ursa Major ("Iso Karhu") or a famous part of it, Big Dipper ("Otava"), or some other constellation of your choice. 

Use sky map's tools to change the time, and pay attention to how the position of the constellation changes in the sky through the night.

2. If the sky is clear during this week, try to find "your" constellation in the sky with the help of the sky map!  

Note: In sky maps North is up and South is down, but East and West are opposite to what you would be used to in normal maps. Think about this so that if you lift the map over your head to try to match the constellations, then your East and West directions would also match the compass directions.

3. Try to find the same constellations in the sky map also in other months of the year. Pay attention to how the local time for when it is visible in each direction changes.

4. Some planets can be seen in the sky early in the morning now. Find them in the sky map, and if the weather permits, try to find them in the sky! 

5. On January 31st there will be a total Lunar eclipse. Unfortunately, it will not be very well visible in Finland, because the Moon rises in Southern Finland only after the total phase has ended. Try, however, to watch it, if the sky is clear! 

Moon rises in Helsinki at 16:30 on January 31st.

Please note: for watching a Lunar eclipse you need no special equipment, unlike for watching a Solar eclipse, where you absolutely must protect your eyes with a proper filter!

More information about the coming Lunar eclipse:


An easy-to-use sky map for Finland:

You can enter the desired viewing date and time in the box below the map, or fast forward/backward. Unfortunately the names of constellations etc. are here only available in Finnish :(

Lots of sky map apps are available for Anrdoid, iPhone, iPad etc. 

Look for SkyMap, for instance. Some of them (including SkyMap) allow you to point into a certain direction in the sky and use the device's sensors to identify the constellations visible in that direction!

Stellarium, -- a sophisticated free planetarium software available for most platforms.

It takes a while to familiarise yourself with all the various properties of this software, but it is a really powerful tool for astronomy enthusiasts! This may also be useful for checking the

answers that you get for your calculations of the exercises.

To get started: Set the desired location in the location menu of the left side menus, and the desired date & time in the date & time window. Especially if you want to study locations of observatories elsewhere in the world, pay attention to the time zone -- the default is your computer's time zone, so it is advisable to change it to UTC time in order not to get


In the search window you can give in the coordinates of your target source, and in the astronomical calculations window you can study for example the elevation vs. time plot of the selected source.

A web-based sky viewing application that lets you study individual objects in more detail. Not so practical for finding your way in the local night sky, though.

Last modified: Monday, 29 January 2018, 11:33 AM