The Sirens of Titan
The northern pole of Pluto, in full high-resolution. Yes, that’s ice–methane ice.
Stunning.
Sunset On Pluto
via reddit
Earth and Moon
The Space Shuttle Discovery blasts off from Cape Canaveral on March 13, 1989.
Spanning from comets in the south to the termination shock zone in the northern part of the country, The Sweden Solar System is a scale model of the solar system that spans the entire country of Sweden, the largest such model in the world.
The Sun is represented by the Ericsson Globe in Stockholm, the largest hemispherical building in the world. The inner planets can also be found in Stockholm but the outer planets are situated northward in other cities along the Baltic Sea.
Image of Saturn taken by Cassini spacecraft in October 28, 2016.
Credit: NASA / JPL / Cassini
This is an animation of how quickly an object falls 1 km to the surfaces of solar system objects like the Earth, Sun, Ceres, Jupiter, the Moon, and Pluto. For instance, it takes 14.3 seconds to cover that distance on Earth and 13.8 seconds on Saturn.
It might be surprising to see large planets have a pull comparable to smaller ones at the surface, for example Uranus pulls the ball down slower than at Earth! Why? Because the low average density of Uranus puts the surface far away from the majority of the mass. Similarly, Mars is nearly twice the mass of Mercury, but you can see the surface gravity is actually the same… this indicates that Mercury is much denser than Mars.
(via @thekidshouldsee)
The latest video from Kurzgesagt is a short primer on neutron stars, the densest large objects in the universe.
The mind-boggling density of neutron stars is their most well-known attribute: the mass of all living humans would fit into a volume the size of a sugar cube at the same density. But I learned about a couple of new things that I’d like to highlight. The first is nuclear pasta, which might be the strongest material in the universe.
Astrophysicists have theorized that as a neutron star settles into its new configuration, densely packed neutrons are pushed and pulled in different ways, resulting in formation of various shapes below the surface. Many of the theorized shapes take on the names of pasta, because of the similarities. Some have been named gnocchi, for example, others spaghetti or lasagna.
Simulations have demonstrated that nuclear pasta might be some 10 billion times stronger than steel.
The second thing deals with neutron star mergers. When two neutron stars merge, they explode in a shower of matter that’s flung across space. Recent research suggests that many of the heavy elements present in the universe could be formed in these mergers.
But how elements heavier than iron, such as gold and uranium, were created has long been uncertain. Previous research suggested a key clue: For atoms to grow to massive sizes, they needed to quickly absorb neutrons. Such rapid neutron capture, known as the “r-process” for short, only happens in nature in extreme environments where atoms are bombarded by large numbers of neutrons.
If this pans out, it means that the Earth’s platinum, uranium, lead, and tin may have originated in exploding neutron stars. Neat!