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How do jellyfish swim?

Jellyfish float on ocean currents, but they also swim in a couple of different ways. This post has 2 videos showing 2 different jellyfish propulsion mechanisms.

Synchronized symphony of fireflies

This video shows a timelapse journey through Smoky Mountains National Park during world’s largest gathering of synchronized fireflies. Beautiful!

Video: Moon hoax not

SG Collins explains why the Apollo moon landings on the moon in the late 1960s and early ’70s couldn’t have been faked.

Fire ants build with no master plan

Researchers identified simple behavioral rules that allow these tiny creatures to collaboratively build elaborate structures – rafts and towers – with no one in charge.

Soar over Pluto and Charon

To celebrate the 2-year anniversary of New Horizon’s flyover of the Pluto system, NASA released these 2 cool videos. Sail over the surface of Pluto and its large moon Charon.

Moon shadow versus sun reflection

This 5-second video shows a reflected image of the sun – a sun glint – as a bright spot crossing Earth from right to left. It also shows a dark spot – the moon’s shadow – moving the opposite way.

Does your dog pronk?

Among wild animals, pronking may be a way of avoiding predators. But when you see an animal pronk, you can’t but think it’s leaping for joy.

No commands to Mars craft in late July

NASA says to blame the sun for its moratorium on sending commands to Mars from July 22 to August 1.

Astronomers track hypervelocity stars

New video shows 6 hypervelocity stars, zipping from Milky Way center to outskirts. An interaction with our galaxy’s central, supermassive black hole might have kicked them into fast motion.

Solar minimum is coming

Low ebb in the 11-year sunspot cycle expected 2019-2020. Want some basic information about the sunspot cycle and its effects? Watch this NASA ScienceCast.