NASA mission discovers first potentially habitable Earth-sized planet

Watch a giant worm burrow beneath the sand

Watch a flock of starlings fly across a beautiful Irish sunset

Quadrantids to light up the night sky

Watch an elk herd run majestically across the Colorado foothills

Thirsty koala seeks help from bikers in South Australia

New Zealand opens Paparoa Track, first new 'Great Walk' in 25 years

Watch these rescue pups pick out their Christmas presents

Dogs join in singing 'Happy Birthday' for one lucky grandmother

World's oldest married couple celebrate their 80th wedding anniversary

Watch water bubbles become snow globes

'America's Forests' speaks for the trees