Carnival of Space 385 – Understanding dunes of Titan which are as tall as Pyramids of Egypt

The Carnival of Space 385 is up at Photos to space.

The Meridiani journal – Strong winds explain Titan’s immense dunes, according to new study

Saturn’s largest moon Titan is one of the most Earth-like places in the Solar System, as least in terms of appearances, with its seas, lakes, and rivers (of liquid methane/ethane). But it is similar in another way as well, with vast stretches of huge wind-blown dunes in its equatorial regions. Only Earth, Venus, and Mars are known to have such dunes. Now, scientists think they have figured out how Titan’s dunes can become so immense in size: fast-blowing winds.

The dunes cover about 13 percent of Titan’s surface, stretching over an area of 4 million square miles (10 million square kilometers). That’s about the same surface area as the United States. On average, they are 0.6 to 1.2 miles (1 to 2 kilometers) wide, hundreds of miles (kilometers) long, and around 300 feet (100 meters) high. Their size and spacing can vary, however, according to location. They are similar in shape to the linear dunes found on Earth in Namibia or the Arabian Peninsula, but on larger scales, and confined to the equatorial region, in a band between 30 degrees south latitude and 30 degrees north latitude.

Dunes in the Belet and Fensal regions of Titan, compared with Oman and Kalahari dunes on Earth. Image Credit: NASA/JPL-Caltech, and NASA/GSFC/METI/ERSDAC/JAROS and U.S./Japan ASTER Science Team

Red Pyramid was 104 meters tall

The Red Pyramid, also called the North Pyramid, is the largest of the three major pyramids located at the Dahshur necropolis.

Heights of Pyramids and Pyramid shaped buildings

The tallest pyramids at Giza are about 143 meters tall

Nature Geoscience – Sand dune patterns on Titan controlled by long-term climate cycles

The Meridiani journal – Curiosity rover finds methane and organics on Mars

Nextbigfuture – How do METs (Mach Effect Thrusters) work? A new presentation presents improved theoretical work and updated experiments.

• METs depend on “Mach’s principle” being correct.
• Mach’s principle is the proposition that all inertial forces – the forces of reaction in Newton’s third law of mechanics – are produced by the gravitational action of all of the “matter” (everything that gravitates) in the universe.
• In our universe, the conditions needed for this to be true in general relativity are those in fact observed – spatial flatness at cosmic scale.
• When the action of gravity on accelerating local objects is analyzed in relativistically correct fashion, it is found that the rest masses of accelerating objects that are also changing their internal energies (being squished) change. They fluctuate.
• If these rest mass fluctuations are produced periodically, and a second periodic force is brought to bear, you can push heavy, pull light on the fluctuating mass and produce a steady thrust.

Nextbigfuture – The theory and experiments for Mach Effect Thrusters look good and are worth scaling. If it proves out and does scale with better materials and higher power levels (into the megawatt ranges) then it could enable propellantless propulsion up to 1G space drive and beyond.

Nextbigfuture – Sonny White updates his space warping and emdrive experiments in a video presentation at Ames NASA