North America to scale on various planets

The vast majority of objects out there in the universe are pretty big…moons, planets, stars, galaxies, so it can be difficult sometimes to get your head round their actual size.
With the huge continent of North America dwarfed by Jupiter’s storms, the universe seems an even larger place. In the other direction, Mars looks so much more human-scaled.
This is how North America looks like in relation to Jupiter, one of the giant planets:
planet size-USA
But this is what it lookslike on Mars:
planet size-USA Mars
Read more about it here:
http://astronomycentral.co.uk/astronomy-the-size-of-stuff/

Philea robot lands on comet

Philae_landing

Congratulations, European Space Agency, you’ve made history! After departing from the Rosetta orbiter this morning, touchdown of the robot named Philae onto Comet 67P/Churyumov-Gerasimenko was confirmed at 16:05 GMT. This is a momentous occasion for space exploration as it marks the first time that a spacecraft has ever landed on the surface of a comet.

The Rosetta mission was dreamt up in the ‘80s, but it was not until 1993 that the $1.6 billion (€1.3 billion) project was approved and construction of the crafts could be initiated. That means the probes were fabricated using some systems that were undoubtedly invented in the 1980s, making the mission’s accomplishments even more remarkable.

Rosetta’s rocky voyage began in 2004 after two ditched launch attempts. It took a decade to reach the comet in August this year, a journey that covered six billion kilometers (3.75 billion miles) of our inner solar system.

More on IFL Science.

The grumpiest frog ever!

blackrainfrog

This frog with a perpetual frown isn’t actually grumpy — that’s just how the Black Rain Frog looks! This grouchy-faced amphibian has the most intimidating face around.

The Black Rain Frog is a burrowing amphibian that is native to the southern coast of Africa. One characteristic possessed by this frog is that they burrow to create tunnels up to 150 mm deep.

This frog has a special defense mechanism in case of attack. When someone scares him or tries to grab him, he puffs himself up with air to make his body more rotund.  So, he ends up looking like a grumpy little balloon…

Freezing a hand in hot ice

In this video a man sticks his hand into a jar full of molten sodium acetate and has it crystallize with his hand inside.

This works because the substance is not “ice” as in water, but a different substance called sodium acetate trihydrate. Normally solid sodium acetate was melted into a liquid that was then supercooled to below its melting point. In this state, adding nucleation sites, like the crystals on the man’s hand, rapidly causes the rest of the sodium acetate to crystallize.

via ▶ Hand in Hot Ice – YouTube.