Starship Asterisk*

Villarrica Volcano Against the Sky

Explanation: When Vulcan, the Roman god of fire, swings his blacksmith's hammer, the sky is lit on fire. A recent eruption of Chile's Villarrica volcano shows the delicate interplay between this fire -- actually glowing steam and ash from melted rock -- and the light from distant stars in our Milky Way galaxy and the Magellanic Clouds galaxies. In the featured timelapse video, the Earth rotates under the stars as Villarrica erupts. With about 1350 volcanoes, our planet Earth rivals Jupiter's moon Io as the most geologically active place in the Solar System. While both have magnificent beauty, the reasons for the existence of volcanoes on both worlds are different. Earth's volcanoes typically occur between slowly shifting outer shell plates, while Io's volcanoes are caused by gravitational flexing resulting from Jupiter's tidal gravitational pull.

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Living on the benign surface of this earth it is difficult to imaging the enormous forces that exist under our feet, and to an even greater extent, the mind bending forces that come into play between the stars and dust of our galaxy. This short video does something to bring them both into focus.

As Bob Dylan sang:

"..to dance beneath the diamond sky, with one hand waving free"

APOD Robot wrote: ↑Wed Jul 17, 2024 4:05 am ... while Io's volcanoes are caused by gravitational flexing resulting from Jupiter's tidal gravitational pull.

It’s not just Jupiter. The orbital resonances with Europa and Ganymede also contribute.

I might have misunderstood this, but what are the several flashes of light on the ground? Lightning strikes?

Also, the reason for volcanoes on both Earth and Io is ultimately due to a molten interior in both cases, with Earth's caused by a radioactive core and Io's caused by tidal flexing.

PS - it still amazes me that even after 4 billion years, the Earth is still spewing molten rock! How long will this go on - another 4 billion years?

johnnydeep wrote: ↑Wed Jul 17, 2024 1:38 pm I might have misunderstood this, but what are the several flashes of light on the ground? Lightning strikes?

The landscape is lit from car headlights on the road on the left. Set playback speed to 0.25 to see them.

NateWhilk wrote: ↑Wed Jul 17, 2024 4:19 pm

johnnydeep wrote: ↑Wed Jul 17, 2024 1:38 pm I might have misunderstood this, but what are the several flashes of light on the ground? Lightning strikes?

The landscape is lit from car headlights on the road on the left. Set playback speed to 0.25 to see them.

Thanks. I did that but still saw no actual cars, just lights traveling from left to right most of the time, but not always.

JimB wrote: ↑Wed Jul 17, 2024 8:52 am Living on the benign surface of this earth it is difficult to imaging the enormous forces that exist under our feet, and to an even greater extent, the mind bending forces that come into play between the stars and dust of our galaxy. This short video does something to bring them both into focus.

As Bob Dylan sang:

"..to dance beneath the diamond sky, with one hand waving free"

When thinking about the benign. Don't forget about what is just beneath the surface of you. Can you hear the blood in your ears when you lay down at night and are ill? Can you feel your chest pump when you're excited? And when it's time to visit that black hole in the morning do you not feel relieved getting rid of waste? All these questions were created by stardust forged along ago. Stardust contemplating the benign.