Sustainable Aviation Fuel Remains Wishful Thinking

The American non-profit Institute for Policy Studies has compared plans with the reality of sustainable aviation fuels (SAF). The term SAF is a catch-all for alternatives to fossil fuel in aviation, either by deriving fuel from crops or waste oil, or by synthetically producing it using renewable energies. The report details that not only is the global share of SAF of all aviation fuel still below 0.1%, but also the production has barely reached 1% of targets set by the International Air Transport Association. To meet the Biden administration’s 2050 target of 35 billion gallons of production per year, production would have to increase more than five orders of magnitude over 2022 production levels. The brief summary is that, realistically, this isn’t going to happen. Report here.

Check out this video on Einstein's unified field theory! Einstein completed his theory of general relativity in 1915 when he was 37 years old. What did he do for the remaining 40 years of his life? He continued developing his masterwork of course! You can take the quiz here.

Astronomers Find Seven Candidates for Dyson Spheres

Dyson Spheres – named after Freeman Dyson – are hypothetical megastructures built by highly advanced civilizations around their stars to harness energy. Compared to normal stars, such structures would appear unnaturally dim in the visible range but still emit waste heat in the infrared. By meticulously analysing vast astronomical datasets, including optical and infrared observations from Gaia, 2MASS, and WISE, a group of astrophysicists has identified seven possible candidates that will now be studied closer. Paper here.

Learn Science Through Storytelling

You all know that I like my science without all the unnecessary confusion. Nautilus is a free newsletter that uses the power of storytelling to break down complex scientific concepts into fun, intriguing stories. Delve deeper and rediscover the joys of learning with Nautilus.

No, Dark Matter’s Rival Theory is Still Not Dead

Cassini mission, artistic rendering. Image: NASA/JPL

In a recent article in The Conversation, titled “Is dark matter's main rival theory dead?,” two astronomers claim that Modified Newtonian Dynamics (MOND) is not compatible with data collected by the Cassini mission. The Cassini mission was a space mission to Saturn, and its orbit implicitly measured the orbit of Saturn very precisely. The mission ended in 2017 with a final plunge and burn-up in Saturn’s atmosphere. If one looks at the paper they are referring to, however, it turns out that it is not testing MOND but rather two theories that are sometimes used to derive MOND, called AQUAL and QUMOND. In other words, the answer to the question in the title is “no.” Paper here.

Our podcast “Science with Sabine” is available on Spotify, Amazon, Apple, Castbox, Google Podcasts, Pocket Casts, Radio Public, and YouTube.