The rocky planets Mercury, Venus, Earth, and Mars were born at the same time from the same material - yet have lived radically different lives. What immense forces are at play?
This episode documents how gravity has an effect across the universe, and how the relatively weak force creates an orbit. We also see how a neutron star's gravity works. Finally, there is a look back at how research on gravity has enabled us to better understand the cosmos.
Beginning with the origins of the universe in the Big Bang, Sagan describes the formation of different types of galaxies and anomalies such as galactic collisions and quasars. The episodes moves further into ideas about the structure of the Universe, such as different dimensions (in the imaginary Flatland and four-dimensional hypercubes), an infinite vs. a finite universe, and the idea of an oscillating Universe (similar to that in Hindu cosmology). The search into other ideas such as dark matter and the multiverse is shown, using tools such as the Very Large Array in New Mexico. Cosmos Update shows new information about the odd, irregular surfaces of galaxies and the Milky Way perhaps being a barred spiral galaxy.
The first close-up images of Pluto revealed unimaginable secrets of this mysterious frozen world. Now, scientists investigate if Pluto is home to a warm ocean of liquid water beneath its surface, and whether this underground ocean could harbour life.
For twenty years, NASA's Cassini spacecraft revealed the strange secrets of Saturn until it vaporized in its atmosphere in a blaze of glory. But today its legacy lives on, as fresh data from the probe helps scientists make brand-new discoveries.
Suppose you placed a camera at a fixed position, took a picture of the sky at the same time every day for an entire year, and overlaid all of the photos on top of each other. What would the sun look like in that combined image? A stationary dot? A circular path? Neither. Oddly enough, it makes a ‘figure 8’ pattern, known as the Sun’s analemma.
Astronomers are laying the groundwork to locate a new planet for the human race to inhabit, and the more alien worlds they discover and encounter, the more they unmask the mysterious and truly destructive nature of the cosmos.