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Wikipedia dicit:

A rotating detonation engine (RDE) is an engine using a form of pressure gain combustion, where one or more detonations continuously travel around an annular channel. Computational simulations and experimental results have shown that the RDE has potential in transport and other applications.

In detonative combustion, the flame front expands at supersonic speed. It is theoretically more efficient than conventional deflagrative combustion by as much as 25%. Such an efficiency gain would provide major fuel savings.

The basic concept of an RDE is a detonation wave that travels around a circular channel (annulus). Fuel and oxidizer are injected into the channel, normally through small holes or slits. A detonation is initiated in the fuel/oxidizer mixture by some form of igniter. After the engine is started, the detonations are self-sustaining. One detonation ignites the fuel/oxidizer mixture, which releases the energy necessary to sustain the detonation. The combustion products expand out of the channel and are pushed out of the channel by the incoming fuel and oxidizer.

Video credit: NASA’s Marshall Space Flight Center

NASA dicit:

The entire gamma-ray sky is shown as two circular views centered on the north (left) and south poles of our Milky Way galaxy in this 14-year time-lapse of the gamma-ray sky. The central plane of our galaxy wraps around the edges of both circles, suppressing its glow and improving the view of black-hole-powered galaxies in the distant universe. Their gamma rays come from jets produced by supermassive black holes in distant galaxies that point almost directly toward Earth, which enhances their brightness and variability. Over a few days, these galaxies can erupt to become some of the brighest objects in the gamma-ray sky and then fade to obscurity. A moving source, our Sun, can be seen arcing up and down the circles as it appears to move through the sky, a reflection of Earth’s annual orbital motion. Watch for strong flares that occasionally brighten the Sun. In these maps, brighter colors indicate greater numbers of gamma rays detected by Fermi’s Large Area Telescope from Aug. 10, 2008, to Aug. 2, 2022.

Video credit: NASA

Wikipedia dicit:

Features on Mars that resemble dry riverbeds and the discovery of minerals that form in the presence of water indicate that Mars once had a dense enough atmosphere and was warm enough for liquid water to flow on the surface. However, that thick atmosphere was somehow lost to space. Scientists suspect that over millions of years, Mars lost 99% of its atmosphere as the planet’s core cooled and its magnetic field decayed, allowing the solar wind to sweep away most of the water and volatile compounds that the atmosphere once contained.

The goal of MAVEN is to determine the history of the loss of atmospheric gases to space, providing answers about Martian climate evolution. By measuring the rate with which the atmosphere is currently escaping to space and gathering enough information about the relevant processes, scientists will be able to infer how the planet’s atmosphere evolved over time.

Video credit: NASA Goddard

NASA dicit:

NASA is working with several American companies to deliver science and technology to the lunar surface through the Commercial Lunar Payload Services (CLPS) initiative.

These companies, ranging in size, bid on delivering payloads for NASA. This includes everything from payload integration and operations, to launching from Earth and landing on the surface of the Moon. Under Artemis, commercial deliveries beginning in 2023 will perform science experiments, test technologies, and demonstrate capabilities to help NASA explore the Moon as it prepares for human missions. CLPS contracts are indefinite delivery, indefinite quantity contracts with a cumulative maximum contract value of $2.6 billion through 2028.

Video credit: NASA