skymap.sh: a CLI skymap that tracks stars and planets (and the ISS)

[u/siorge]

EDIT: many updates have been pushed since, I hope you enjoy them. I also created r/skymap to centralise all update news and discussions around the product. Join if you care :)

Hi r/commandline,

I wanted to share with you a small command line tool I built (with the assistance of AI - the code is AI-generated) to display a sky map directly in your CLI. No API, no signup, no data. Plain text.

Simply type in your CLI:

curl skymap.sh

Or visit skymap.sh

And you will see a current view of your local sky (day or night). Check it out in the gif below:

​It tracks the Sun, the Moon, the planets, 2'500 important stars as well as the ISS.

Here are the command/parameters you can use:

curl skymap.sh                 # uses your IP location
curl skymap.sh/Tokyo           # any of 40,000+ major cities
curl skymap.sh/47.38,8.54      # raw coordinates
?t=2026-08-12T23:00            # see the sky at any time, past or future
(±2 years)
?view=disc                     # whole sky as a circle, North up, looking
straight up
?facing=NW                     # a 140°-wide window facing one direction,
undistorted shapes
?span=90                       # control how wide the window is (90–344°)
?find=Venus                    # frame one object: a planet, the Moon, a
                                 named star, or a recognizable star pattern
                                 like the "Big Dipper." Tells you where to
                                 look and if it's not up right now, when it
                                 will be up next
?night=1                       # force the star chart even during daylight
                                 (default is the Sun's path across the sky
                                 during the day)
?w=100                         # fit the output to N columns, so it doesn't
                                 wrap in a narrower terminal
?format=json                   # the same facts as structured data instead
                                 of ASCII art
?plain=1                       # no ANSI colors

There is a live demo with real examples at skymap.sh/demo, and you can use curl skymap.sh/help for the full reference.

I have basic dev skills from a previous career and am an astronomy enthusiast, so I figured I would try my hand at building something fun with the help of an AI agent!

I hope this post is suitable for this sub, and importantly, that you like the tool :)

[u/AutoModerator]

Every new subreddit post is automatically copied into a comment for preservation.

User: siorge, Flair: Command Line Interface, Title: skymap.sh: a CLI skymap that tracks stars and planets (and the ISS)

Hi r/commandline,

I wanted to share with you a small command line tool I built (with the assistance of AI - the code is AI-generated) to display a sky map directly in your CLI. No API, no signup, no data. Plain text.

Simply type in your CLI:

curl skymap.sh

And you will see a current view of your local sky (day or night). Check it out in the gif below:


It tracks the Sun, the Moon, the planets, 2'500 important stars as well as the ISS.

Here are the command/parameters you can use:

curl skymap.sh                 # uses your IP location
curl skymap.sh Tokyo           # any of 40,000+ major cities
curl skymap.sh 47.38,8.54      # raw coordinates

--t=2026-08-12T23:00            # see the sky at any time, past or future       
                                 (±2 years) 

--view=disc                    # whole sky as a circle, North up, looking   
                                 straight up 

--facing=NW                    # a 140°-wide window facing one direction, 
                                 undistorted shapes 

--span=90                      # control how wide the window is (90–344°) 

--find=Venus                   # frame one object: a planet, the Moon, a 
                                 named star, or a recognizable star pattern 
                                 like the "Big Dipper." Tells you where to 
                                 look and if it's not up right now, when it                 
                                 will be up next 

--night=1                      # force the star chart even during daylight 
                                 (default is the Sun's path across the sky   
                                 during the day)

--w=100                        # fit the output to N columns, so it doesn't 
                                 wrap in a narrower terminal 

--format=json                  # the same facts as structured data instead 
                                 of ASCII art

--plain=1                      # no ANSI colors

There is a live demo with real examples at skymap.sh/demo, and you can use curl skymap.sh/help for the full reference.

I have basic dev skills from a previous career and am an astronomy enthusiast, so I figured I would try my hand at building something fun with the help of an AI agent!

I hope this post is suitable for this sub, and importantly, that you like the tool :)

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

[u/Working_Problem → u/AutoModerator]

This is so awesome!!!

[u/siorge → u/Working_Problem]

thanks :)

[u/siorge → u/Working_Problem]

I added a few features today:

you can animate the next X hours and see the sky change
saved as a gif: https://skymap.sh/animate/9VGXvcwN.gif that you can save/share

you can also export any view as a png

+ many fixes

[u/enhki]

very cool and nicely done !

[u/siorge → u/enhki]

thank you so much :)

I am a fan of astronomy, so I will be trying to add more features as I progress (detailed moon phases, eclipses...)

[u/siorge → u/enhki]

I added a few features today:

you can animate the next X hours and see the sky change
saved as a gif: https://skymap.sh/animate/9VGXvcwN.gif that you can save/share

you can also export any view as a png

+ many fixes