2. Dendrite Snowflake photo by Kenneth Libbrecht
Dendrite snowflakes first occur when the temperature hovers between 30
degrees Fahrenheit (-1 degree Celsius) and 27 degrees Fahrenheit (-3
degrees Celsius).
3. Ice Cave Ceiling photo by Carsten Peter
Peaks and valleys ripple across the ceiling of an ice cave in
Bavaria, Germany.
4. Snowflake Crystal photo by John Dunn
A snowflake appears translucent when photographed up-close.
5. Ice Fractures photo by John Dunn
Fractures create ribbon-like patterns in thick ice on Ellesmere
Island, Canada.
6. Sectored Plate Snowflake photo by Kenneth
Libbrrecht
A snowflake's shape depends on the temperature at which it forms. This type
of snowflake, called a sectored plate, forms when the temperate dips below
about 5 degrees Fahrenheit (-15 degrees Celsius).
7. Plate Snowflake photo by Kenneth Libbrecht
Scientists aren't sure why temperature affects crystal formation and leads
to different shapes of snowflakes.
8. Snowy Hills photo by Jay Dickman
The sun casts shadows on snow-covered hills in North America.
9. Sandbars in Australia photo by Paul Chelsey
Sandbars flow into the Coral Sea at Whitsunday Island National Park in
Queensland, Australia.
10. Whirlpool photo by James A. Sugar
Turbines at the Barrage de la Rance electric power generating station in
France create a whirlpool in the Rance River.
11. Pismo Beach, California photo by Marc Moritsch
Waves from the Pacific Ocean leave lines in the sand at Pismo Beach in
California.
12. Sea Ice, Beaufort Sea photo by Paul Nicklen
Thick sea ice in the Arctic Ocean's Beaufort Sea traps air bubbles.
14. Lake Magadi, Kenya photo by Emory Kristof
In the midst of a full algae bloom, the waters of Kenya's Lake Magadi run
red.
15. Neglected Eighty-eight Butterfly photo by Joel
Sartore
A neglected eighty-eight butterfly (Diaethria neglecta) in Brazil’s Pantanal
displays the design of lines and dots that gave it its unusual common name.
16. Birdwing Butterfly photo by Nicole Duplaix
Australia’s largest butterfly, the birdwing (Ornithoptera priamus) blends into a
green leaf. Female birdwings can have a wingspan of nearly 8 inches (20
centimeters).
17. Butterfly wing photo by Darlyne Murawski
A close-up of the wing of an unidentified butterfly found near
Tully, Australia, evokes a rich tapestry.
18. Peacock Pansy photo by Tim Laman
The peacock pansy butterfly (Junionia almana) sports striking eyespots
and purple patterns.
19. Zebra Winged photo by Joel Sartore
The petals of a white flower set off the white stripes of this zebra-winged
butterfly at a children’s zoo in Lincoln, Nebraska.
20. Fire Urchin
The spines of a fire urchin (Asthenosoma varium) form a multicolored flower off
Komodo Island, Indonesia. The blue swellings on the tip of each spine are filled
with venom.
21. Necklace Sea Star photo by Wolcott Henry
A necklace sea star nestles among the C-shaped emerald tentacles of
anchor coral in the western Pacific Ocean.