Turn Your Phone into a Window and Explore the Night Sky
The second article in Tech for the Fun of It—simple, enjoyable things you can do with everyday technology, explained clearly and without jargon
Have you ever looked up at a bright point in the evening sky and wondered whether it was a star, a planet or perhaps even a satellite?
With the right app, your phone can become a pocket-sized guide to the night sky. Point it upwards and it can show you the names and positions of stars, planets and constellations above you.
You do not need a telescope, specialist knowledge or expensive equipment. For this activity, we will use the free version of Stellarium Mobile, which is available for Apple and Android devices.
Stellarium describes its app as a realistic simulation of the sky at a chosen time and location. It includes stars, planets, constellations, satellites, sensor control and a red night mode. The free version has everything required for this activity; you do not need to purchase Stellarium Plus. Learn more from Stellarium.
Let’s step outside and find out what is waiting above us.
What we’re going to discover when we explore the night sky with your phone
In this activity, you will learn how to:
install a trustworthy stargazing app;
allow it to display the sky above your location;
point your phone towards the sky;
identify a bright star, planet or constellation;
search for an object you would like to find;
use red night mode to protect your night vision; and
begin recognising the Southern Cross without relying entirely on your phone.
The aim is not to spend the evening staring at another screen. Your phone is the guide—not the destination.
Use your phone to explore the night sky and identify something, put it down and then enjoy the real sky with your own eyes.
What you’ll need
You will need:
an iPhone, iPad, Android phone or Android tablet;
an internet connection to install the app;
the free Stellarium Mobile – Star Map app;
a reasonably clear evening;
a safe outdoor place with a view of the sky; and
perhaps a comfortable chair.
A suburban backyard is perfectly suitable for your first attempt. You do not need to travel to a remote location, although fewer nearby lights will make fainter stars easier to see.
Clouds, smoke, bright streetlights and moonlight can reduce the number of visible stars. If the sky is not cooperating tonight, simply try again another evening.
Simple step-by-step instructions
Step 1: Install Stellarium Mobile
On an iPhone or iPad:
Open the App Store.
Tap Search.
Enter Stellarium Mobile – Star Map.
Check that the developer is Noctua Software Ltd.
Tap Get.
The Apple listing describes the app as free with optional in-app purchases. View Stellarium Mobile in the Australian App Store.
On an Android phone or tablet:
Open the Google Play Store.
Search for Stellarium Mobile – Star Map.
Check that the developer is Noctua Software.
Install the standard free version.
You may also see a paid application called Stellarium Plus. That version includes advanced features for serious observers and telescope owners. It is not required for this activity.
Do not install an application from a link in an unsolicited email, text message or pop-up advertisement. Use only the official App Store or Google Play Store.
Step 2: Open the app and check your location
Open Stellarium Mobile.
The app may ask for permission to use your location. Choose the option that permits access while you are using the app.
Your location allows Stellarium to calculate which stars and planets should be above your horizon. The sky visible from Darwin is different from the sky visible from London, and the view also changes according to the time of night and the date.
You do not normally need to enter your street address. The phone’s approximate location is sufficient for casual stargazing.
If the app appears to show the wrong sky, check:
that location services are turned on;
that Stellarium has permission to use your location;
that your phone has the correct date and time; and
that the displayed location is reasonably close to where you are.
The app’s appearance may change slightly after an update, so do not be concerned if a button is in a slightly different position from the one described here.
Step 3: Become familiar with the screen indoors
Before going outside, spend a few minutes examining the app somewhere well lit.
The screen represents the sky. You should see:
stars of different brightness;
lines or artwork marking constellations;
the horizon;
compass directions such as north, south, east and west;
the Moon or visible planets, depending on the time; and
controls for searching, settings and sensor movement.
Drag one finger across the screen to move around the sky manually.
Pinch two fingers together to zoom out. Spread them apart to zoom in.
Tap a star, planet or other object. Its name should appear, often with an option to display more information.
Do not worry about understanding every symbol or control. We need only a few of them today.
Step 4: Prepare for your first viewing
Choose a safe location before it becomes completely dark.
A suitable place might be:
your backyard;
a veranda with an unobstructed view;
a level driveway away from vehicle movements;
a familiar park that is open and safe after dark; or
a friend’s property away from bright lights.
Check the ground for steps, garden edging, hoses, loose stones or other hazards.
If possible, use a stable outdoor chair. Looking upwards for an extended period can become uncomfortable, and sitting also reduces the temptation to walk while watching the phone.
Reduce the screen brightness before you begin.
Stellarium also includes a red night mode designed to preserve your eyes’ adjustment to darkness. Its exact location can vary with the app version, but look in the main menu or display settings for a night-mode symbol or red-screen option.
It can take approximately 15 to 20 minutes for your eyes to become more sensitive to low light. Looking at a bright white screen will interrupt that adjustment.
Step 5: Let the phone follow the sky
Stellarium can use the direction sensors in a compatible phone to make the map follow your movements.
Look for the compass or sensor control, commonly near the bottom of the screen. Select it and choose Auto, if that option appears.
Hold the phone securely and point its back towards the part of the sky you are viewing.
Move slowly.
As you turn or raise the phone, the star map should move with you. It should display the stars and other objects located in that direction.
Stellarium’s guidance explains that Sensor Mode can follow the direction in which the phone is pointed. This feature requires a phone fitted with a compass or magnetometer. See Stellarium’s Sensor Mode explanation.
If the map swings around wildly or points in the wrong direction, do not assume you have done something wrong. Phone compasses are easily disturbed by nearby metal or magnets. The troubleshooting section below will help.
Step 6: Identify your first object
Begin with something obvious.
Good first targets include:
the Moon;
a particularly bright planet;
one of the brightest visible stars; or
the Southern Cross.
Point the phone towards the object. When it appears on the screen, tap it.
The app should display its name. Depending on the object, you may also be able to view:
whether it is a star, planet, moon or satellite;
its distance from Earth;
its position in the sky;
its brightness; and
a short description.
Now lower the phone and look at the object directly.
Try this several times:
Look at the sky.
Choose something interesting.
Use the app to identify it.
Lower the phone.
Find the object again without assistance.
That final step is where the real learning takes place.
Step 7: Search for something you want to find
Stellarium includes a search function, usually represented by a magnifying-glass symbol.
Tap Search and enter the name of an object, such as:
Moon;
Southern Cross;
Alpha Centauri;
Jupiter;
Saturn; or
International Space Station.
Select the correct result.
The app should indicate where the object is located. You may need to move the phone until an on-screen marker reaches the centre of the display.
An object may be:
above the horizon and visible;
above the horizon but concealed by clouds, trees or buildings;
too faint to see without binoculars or a telescope; or
below the horizon at that time.
The app can show you where an object should be, but it cannot make clouds disappear or make a faint galaxy visible to the naked eye.
Step 8: Find the Southern Cross
The Southern Cross—also called Crux—is a natural first constellation for an Australian observer.
It is smaller than many people expect. Four prominent stars form the main cross, with a fifth star also belonging to the constellation.
Two bright nearby stars, commonly called the Pointer Stars, help lead the eye towards it.
To find it:
Open Search in Stellarium.
Enter Southern Cross or Crux.
Select the result.
Follow the app’s guide towards the correct part of the sky.
Look generally towards the south.
Locate the cross-shaped group of stars.
Lower your phone and try to identify it again unaided.
The Southern Cross changes its apparent angle during the night and through the year. It will not always appear upright like the cross on the Australian flag.
Once you can find it without assistance, you have begun learning the sky rather than merely reading the app.
Something extra to try
Compare a star and a planet
Stars produce their own light. Planets reflect sunlight.
To the naked eye, bright planets often appear steadier than stars, which may twinkle more noticeably because their light is disturbed by Earth’s atmosphere.
Use Stellarium to identify a bright point, then see whether you can tell if it is a star or a planet before reading the answer.
This is a useful observation rather than an infallible rule. Atmospheric conditions and a planet’s position near the horizon can change its appearance.
Watch the sky change with time
Stellarium can simulate the sky at a different time or date.
Try advancing the display by several hours and watch how the stars appear to move across the sky. The stars are not circling Earth each night; the apparent movement is caused mainly by Earth rotating.
You can also choose a different season and see which constellations will be visible later in the year.
Before changing the time, make a note of how to return to Now or the current time.
Look for the International Space Station
Search for International Space Station or ISS.
The app may show its current position or a future pass. Satellite visibility depends on timing, your location and whether the satellite is illuminated by sunlight while the sky around you is dark.
If you see a bright point moving steadily across the sky without flashing like an aircraft, you may be watching a satellite.
Invite someone to join you
Stargazing becomes more enjoyable when discoveries can be shared.
Invite a partner, friend, child or grandchild outside. Take turns choosing an object and using the phone to identify it.
Try keeping a simple list titled:
Things we found tonight
Your first list might include the Moon, Southern Cross, Alpha Centauri and one visible planet.
Try again away from bright lights
After learning the controls at home, compare the view from a darker—and safe—location.
Allow your eyes time to adjust. You may be surprised by how many additional stars appear when you move away from streetlights and brightly lit buildings.
A short privacy and safety note
Location permission
Stellarium uses your location to calculate the correct sky.
Granting access while using the app is generally sufficient. There is no reason for a basic stargazing activity to require location access at all times.
You can later review or remove the permission in your phone’s privacy or application settings.
Optional purchases
The free version is sufficient for this activity. You may see offers to upgrade to Stellarium Plus or begin a subscription.
Do not approve a purchase unless you deliberately want the advanced features and understand whether the payment is once-only or recurring. The Apple listing confirms that the free app contains optional in-app purchases. Review the current App Store listing.
Look where you are going
Do not walk while looking upwards or watching the phone.
Stop in a safe place before using the app. Take particular care around:
steps and uneven paths;
roads and driveways;
swimming pools;
garden tools and hoses;
low branches;
wildlife; and
poorly lit public places.
Let someone know where you are going if you leave your property at night.
Protect your night vision
Use red night mode, reduce screen brightness and avoid shining a bright torch towards other observers.
A small red-light torch can help you move safely without completely disrupting your adjustment to darkness.
How to undo it or get help
There is very little to undo. Exploring the sky does not change your phone or the stars.
If the map does not follow the phone
Try the following:
Move the phone slowly in a gentle figure-eight pattern. This may help recalibrate its compass.
Move away from cars, metal furniture, speakers and other large metal objects.
Remove a magnetic phone case or wallet temporarily.
Check that the app has location permission.
Confirm that your date, time and location are correct.
Close and reopen the app.
If your phone does not include a compass sensor, automatic pointing may not work. You can still explore by dragging the map with your finger and using the search function.
If the display is pointing in the wrong direction
Check the compass directions shown on the screen against the real direction you are facing.
Metal structures and magnets can produce a large error. Move several metres away and try again.
If you cannot see the object shown by the app
The object may be:
behind a tree, roof or cloud;
below your local horizon;
washed out by moonlight or city lighting;
too faint for unaided viewing; or
correctly positioned but difficult to recognise.
Try the Moon or a very bright star first. Success with an easy target will confirm that the app and location settings are working.
If you want to return to the present
If you have experimented with the date or time controls, look for Now, Current time or a clock-reset symbol.
If you no longer want the app
You can uninstall it like any other application.
On an iPhone or iPad, touch and hold the app icon, choose Remove App, then Delete App.
On Android, touch and hold the app icon and choose Uninstall, or remove it through Settings > Apps.
Printable quick-reference guide
We have prepared a one-page A4 guide covering installation, first use, troubleshooting and safe night viewing.
[Download the Night Sky Quick-Reference Guide]
Print it before going outside so you do not need to keep returning to the full article.
Tonight’s challenge
Find the Moon or the Southern Cross.
Identify it with Stellarium, lower the phone and then find it again using only your eyes.
Your phone may open the window—but the real view is above it.
FAQ's
Can my phone identify stars and planets?
Yes. A planetarium app uses your location, time and phone sensors to display the part of the sky towards which the phone is pointed.
Is Stellarium Mobile free?
The standard Stellarium Mobile app is free and includes the features needed for this activity. Optional paid upgrades provide additional advanced functions.
Do I need a telescope?
No. Begin with objects visible to the naked eye, including the Moon, bright stars, planets and major constellations.
Why does the star map point in the wrong direction?
The phone’s compass may need recalibration or may be affected by nearby metal or magnets. Move away from metal objects, remove magnetic accessories and gently move the phone in a figure-eight pattern.
Can I use the app without a phone compass?
Yes, but the map may not automatically follow the phone. You can drag the sky manually and use the search function.
Does the app need my location?
It needs at least an approximate location to calculate the correct sky. Location access while using the app is normally sufficient.
Why can’t I see an object shown in the app?
It may be obscured by clouds, buildings or trees, affected by light pollution, below the horizon or too faint to see without optical assistance.
Tech for the Fun of It is an Arafura Consulting & Media series exploring simple, enjoyable things you can do with everyday technology—clearly and without jargon.
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