A good chart nearby when star hopping is a must. Any harder target (a faint fuzzy) needs to be properly identified / compared with the charted area. I first started with printed catalogues and a red light lantern. But that’s a bit cumbersome to use due to humidity for example (the maps get wet during the night). Fast forwarding to a few years later – I rarely use that approach – now the apps installed on my smartphone work like magic. The whole thing is much easier to operate and the additional light from the screen doesn’t ruin your eyes darkness adaptation if you take some precautions (dark night mode app & screen filter).
Whether you want to plan your observation session for tonight or get updated data on comet positions, know when the International Space Station will fly over your observing site or identify other satellites crossing the sky above – then using mobile apps or other online platforms is a must. Let’s have a look at mobile apps. You have a bunch of options to choose from nowadays – depending on your platform of choice – iOS or Android – but most of them are present on both. Then, if there isn’t an app yet to satisfy your requirements then you’ll surely find a site to get that data.
Here’s a list of top 5 apps that are easy to use, intuitive and full of features. Some are more technical and others more visual (you can point your phone to the sky and they’ll identify the constellations – bright stars or other objects – that you’re looking at right in that specific moment.
SkySafari is probably all you need
That’s why SkySafari is probably the one to rule them all (even the free version is amazing). It’s my favorite app due to the huge number of features and ease of use. From planning your observing session to finding objects on the sky (the chart feature) and then saving your observations with tremendous detail; telescope control – it does the job really well.
I’m not gonna perform an exhaustive overview of it’s features (it has a manual and release notes for that) but instead I’d like to talk about those that I think are most practical. It has a night (red) mode, pictures of all the Messier catalogue objects, most NGCs (New General Catalogue), several ICs (Index Catalogue) and more. These pictures often help identifying the object seen in the eyepiece based on different features – dust lanes in galaxies, overall shape, star patterns in the field, etc.
Data about comet orbits or other small planets and asteroids is updated on a regular basis (behind the scenes) so that you end up with an accurate chart for a new comet that’s increasing in magnitude for example – and that you’d like to observe on a certain night.
Stellarium – desktop and mobile
I’ve used Stellarium mostly on desktop. Now it has a mobile app version also. It’s a complete planetarium solution also and with a bunch of stelar and DSO catalogs available to download. You get a full sky overview of the constellations, their boundaries, the Milky Way. You can turn on constellation art in order to help you imagine and remember the constellations better. Time control, realistic atmosphere, sunrise and sunset, telescope control.
Other nice apps – Sky Map, SkEye, Starwalk 2
Google Sky Map is nice and available/compatible on/with most phones and tables (even older models). As a drawback – it has just a few deep sky objects available (the bright ones). It’s updated frequently and was recently open sourced. If you explore it enough you may find some goodies hidden. SkEye is also good as a free star chart, with many stars but a bit ugly interface (in my opinion). Starwalk 2 constellation lines and shapes are gorgeous. Again, choosing between these options is just a matter of taste or preference.
Cartes du Ciel
This is an honorable mention – as an alternative to Stellarium on desktop. Unfortunately the work on this app hasn’t progressed much over the years. The charts rendered are really nice and can be easily printed on paper but I’m not using it for much lately.
Moon(s) themed data
When it comes to our moon I’ve found a bunch of helpful apps. Phases of the moon gets me a quick overview of the phase and current brightness of the Moon, with rise and sunset times (maybe redundant because SkySafari also has this 🙂 ). Then, I’m using two apps that help with charts of the various areas visible on the moon with an amateur telescope: seas, mountains, ridges and craters. It’s a matter of preference really but i’m using both of them from time to time Moon Atlas 3D, Lunar Map Lite.
A useful app for identifying the galilean moons of Jupiter is JoveMoons. You can simulate their positions in a specific interval, find out when the next red spot transit is or when the next shadow of a specific moon will be visible on the planet.
Heavens-above – alternate source for satellites, ISS, comets and meteors data
Another good resource for amateur astronomers is Heavens-Above. Satellites, (Iridium are nice ones even tough they’re getting replaced with a new generation that aren’t supposed to produce predictable flares), alternate maps/positions of comets, details about Lunar and Solar eclipses and more.
My first option for getting up to date with the Solar activity. Short entries about Sun spots, warnings for CMEs (Coronal mass ejections), geomagnetic storms on Earth with areas where Auroras are expected.
Planning your observing sessions
There are multiple approaches here as well. It can be done with SkySafari as well for example, (trough “Tonight’s Best” list that the program compiles based on your location and datetime) but I’m thinking of more specialized tools like Telescopius or the Planner tool from Deep-Skies. Of course that hard cover deep sky catalogues are good as well. But I plan to explore the topic of planning astronomical observations much better in a dedicated entry in the near future.
Phone screen filter apps.
When you’re out there in the field no source of white light should be used. But that’s usually tough to “enforce”, so a good idea is to install an app (Scren Filter) that further decreases the luminosity of your phone as a whole.