AstrotalkUK

Not for profit website/blog on astronomy, space and my writing

Episode 122. Are we alone and the Breakthrough Initiatives

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Dr Pete Worden

For almost 70 years, astronomers have been listening to radio signals from beyond the Solar System, searching for “techno-signatures.” Data collected has increased many folds. Innovative technologies of digital signal processing and artificial intelligence analyse the data in ways never done before. Still, no clear, unambiguous techno or biosignatures have been detected.

You may have heard the announcement about an exoplanet (K2-18b) capable of supporting life, 124 light-years away. The data appears promising, but it is far from definitive.

A two-day Breakthrough Discuss conference held on 23rd and 24th April 2025 in Oxford England, took stock of the latest developments through three main sessions: “Forms of Non-Terrestrial Life”, “The Nature of Consciousness and Intelligence”, and “Detecting Life As We Do Not Know It”.

Breakthough Discuss was overseen by the Chairman of the Breakthrough Foundation, in this interview Dr Pete Worden. A former Brigadier. General, astrophysicist, professor and director of NASA Ames Research Centre talks about

– How and when he became involved with the Breakthrough Initiatives and current status of each
– His reflections on this year’s Breakthrough Discuss
– His interest in astronomy as a child
– What happened to his astronaut application to NASA
– His distant familial connection with his namesake – Al Worden Apollo 15 Command Module Pilot
– His assessment on where we are with the the search for extraterrestrial life and intelligence

Recordings of Breakthrough Discuss presentations are available on the YouTube channel

Episode 120: Prof. Gengxin Xie. A Greenhouse on the Moon

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Chang’e 4. Credit Prof. Xei Gengxin

On Thursday, 3rd January 2019, some water was added to some seeds in a tiny greenhouse. The seeds, cotton, potato, Rape and Arabidopsis sprouted. 

Experiments like this have been conducted many times before. What was special about this one was that it was done on the surface of the Moon.

The guest on this episode is Professor Xie Gengxin from Chongqing University in central China. He was the  Chief Designer of this Bio experiment carried to the Moon on Chang’e 4 in January 2019. The interview was recorded in Milan during the International Astronautical Congress 2024.

In summary

  • The Chang’e 4 lunar mission by China landed on the far side of the moon and conducted a unique biological experiment involving cotton, potato, rape, and Arabidopsis seeds, along with fruit fly eggs and yeast, within a small, sealed greenhouse.
  • The primary goal of the experiment was to determine if plants could germinate and grow on the moon despite the lower gravity, lack of atmosphere, intense sunlight and radiation, and extreme temperature variations.
  • Cotton seeds successfully germinated 22 hours after water was added, marking the first instance of plant growth on the moon. These lunar seedlings grew faster than their counterparts in a control experiment on Earth and showed surprising resilience to the cold lunar night.
  • The experiment’s design included features like passive insulation, active temperature control, a small window for natural sunlight, and anti-fogging technology for the cameras monitoring the growth.
  • The findings suggest that lower gravity and higher radiation might have aided plant growth, and the experiment provided valuable insights and led to the development of technologies relevant to future space-based agriculture and the establishment of lunar habitats.
  • This biological experiment is considered a significant step in China’s lunar exploration program, which includes plans for a future lunar base (the International Lunar Research Station) and further research into creating sustainable ecosystems in space, potentially within lunar lava tubes.
Episode 120. A Greenhouse on the Moon.

Episode 108 – NASA’s Europa Clipper Mission

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The Europa Clipper mission, due for launch in 2024, will arrive and orbit Jupiter in 2030. The third spacecraft to do so after Galileo (in 1995) and Juno (in 2016). The Pioneer and Voyager missions were flybys. The primary objective, as the mission name suggests, is the investigation of Jupiter’s Moon, Europa. Called Europa-Clipper after the 19th-century merchant ships that shuttled between ports at the high-speed then available.

Europa-Clipper will orbit Jupiter, not Europa. This is one of Jupiter’s moons that shows strong evidence of a sub-surface water ocean. During its four-year mission lifetime it will flyby Europa dozens of times looking for conditions suitable for life.

Dr Steven Vance talks about the mission’s goals and current state of readiness. This was recorded in Athens during Cospar 2022. He was the scientific advisor to the 2013 film Europa Report.

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Episode 107 – SETI’s new tool – Technosignatures

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Episode 107 – Dr Hector Socas-Navarro

The Great Wall of China can be seen from space. Actually, it can’t but the idea that a civilisation could build something large on a planetary scale that could be detected from interstellar distances was articulated first by author Olaf Stapledon in 1937 and popularised by Freeman Dyson in the 1960s. Known today as a Dyson Sphere, it is a megastructure built by an alien intelligence that captures almost all the energy emitted by its star. In this episode, Dr Hector Socas-Navarro explains we humans are not there yet but the increasing density of the Earth’s geosynchronous orbit will become detectable in a couple of centuries.

So not yet a Dyson sphere but a ring or a belt, he calls the Clarke-Exobelt may allow alien civilisations to detect humanity’s presence over interstellar distances. In this episode, we discuss the opportunities for SETI to detect artificial structures like this at interstellar distances using the JWST and very large Earth-based telescopes coming online soon.

Links to the resources we discuss are on the episode webpage

Podcast – Museum of Science and the Cosmos of Tenerife
NASA Technosignatures: “Moderately advanced” technologies in transit. Youtube video
Instituto de Astrofísica de Canarias
Museum of Tenerife

Scientific papers

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