By Hassan Dadashi.arani | Esfahan.iran

By Scott Kuhn | Northwest Georgia

By Nigel Nevitt | Tahiche Lanzarote

By Ken Lamberton | Bisbee, AZ, USA

By Aruna Kulkarni | Alaska near Glacier

By Dr Ski | Valencia Observatory Garden

By Dr Ski | Valencia Observatory

By Dr Ski | Valencia Observatory

By kevan hubbard | North Yorkshire Moors national Park, England

By kevan hubbard | North Yorkshire Moors national Park, England

By kevan hubbard | North Yorkshire Moors national Park, England

By kevan hubbard | North Yorkshire Moors national Park, England

By Kathy Wollman | Valley Center, California, USA

By Ken Chan | San Mateo, CA, USA

By Roberto Porto | Teide National Park, Tenerife, Spain

By Tom Marsala | Mojave Desert, Calif