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This assignment is now closed. Thank you to everyone who participated! We had an amazing response. Browse our Open Story to see some of your photos of the new season around the world.
On September 22 -- the start of autumn in the northern hemisphere and spring in the southern hemisphere -- we invite you to take part in CNN iReport's first one-day mobile photography challenge.
Your assignment is simple: On Saturday, use your mobile device to take a photo that illustrates your outdoor surroundings. The photo can be a landscape, skyline, street or action shot -- just make sure it is shot horizontally and is unfiltered.
Tell us what kind of phone you used to take the photo, time you shot it, as well as what the weather was like that moment. If you share it on social media, use the hashtag #hellofall or #hellospring!
The best shots will be showcased on CNN as part of "Our Mobile Society," an initiative examining the impact of mobile technology on our lives.
Uploading instructions
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