1996 08 00 Science et Vie No 947

Magazine Overview

This issue of Science & Vie, dated August 1996, is a special dossier dedicated to Unidentified Flying Objects (UFOs) and the concept of extraterrestrial visitation, under the main headline "OVNIS: Le grand retour" (UFOs: The Great Return). The cover also highlights articles on "SEXUALITÉ: La biologie de la beauté" (Sexuality: The Biology of Beauty), an investigation into "Que faire des déchets nucléaires ?" (What to do with nuclear waste?), and a piece on "NEANDERTAL: Notre frère disparu" (Neanderthal: Our Lost Brother). The magazine features a grand summer contest.

Dossier: OVNI - Le grand retour

The main dossier explores the current vogue for extraterrestrial themes in cinema and science. It begins by acknowledging the recent discoveries of planets outside our solar system, which fuels speculation about life elsewhere. However, it emphasizes the immense distances involved in any potential interstellar travel, suggesting that only physics at the 'edge of imagination' could make such journeys possible.

L'odyssée des petits hommes verts (The Odyssey of the Little Green Men)

This section discusses the resurgence of UFO themes in popular culture, particularly in films. It questions how extraterrestrials might achieve interstellar travel, considering the constraints of physics. While the universe is vast and potentially teeming with planets, the journey to Earth would require overcoming unimaginable distances. The article posits that while imagination is captivated, reason must consider scientific possibilities.

Le vrai visage des soucoupes (The True Face of Saucers)

This part delves into the scientific feasibility of interstellar travel. It highlights the vastness of the observable universe, with galaxies measured in light-years. The speed of light (c) is presented as an absolute limit for any object carrying information, according to Einstein's theory of relativity. However, relativity also predicts time dilation at speeds approaching c, meaning time would slow down for travelers. The article uses the example of a hypothetical journey from Rigel to Earth to illustrate the extreme time differences experienced on the home planet versus the travelers' frame of reference.

Propulsion Systems and Challenges

The issue examines various theoretical propulsion methods. The 'most economical' approach mentioned is nuclear fusion, using hydrogen as fuel, which is abundant in space. However, the 'most powerful' and 'most advanced' method discussed is matter-antimatter annihilation, which is significantly more energetic than fusion but requires vast amounts of antimatter, posing production challenges. The article also touches upon the dangers of traveling at near-light speeds, where even small particles could cause catastrophic damage to a spacecraft due to their immense kinetic energy.

Le plus rapide (The Fastest)

This section focuses on the extreme energy requirements for matter-antimatter propulsion. It notes that producing enough antimatter on Earth would necessitate operating particle accelerators like Fermilab for centuries. Even with such production, the risk of collision with interstellar dust and micro-asteroids at near-light speeds is immense, potentially transforming them into high-energy cosmic rays or even causing the spacecraft to explode.

Le plus écologique (The Most Ecological)

This part discusses a 'solar sail' concept, which uses starlight pressure for propulsion. While ecological, its effectiveness is limited by the size of the sail and the intensity of the starlight. It also briefly mentions ion propulsion, which uses accelerated ionized atoms, and suggests that for long-duration, slow journeys, self-sustaining ecological colonies might be a more feasible approach, potentially using fusion or ion drives.

Le plus réaliste (The Most Realistic)

This section considers ion propulsion, which uses ionized atoms accelerated by electric fields. It also touches upon the concept of self-sustaining colonies traveling through space. For such colonies to reach Earth from a star like Rigel, it would still take an estimated 54,000 years, even at a speed of 3,000 km/s. The article also mentions the possibility of hibernation for long voyages.

Les magiciens de l'Univers (The Magicians of the Universe)

This section explores more speculative physics concepts that could enable faster-than-light travel or shortcuts through space. It introduces the idea of 'wormholes' (trous de ver), theoretical tunnels in spacetime predicted by general relativity. These could potentially connect distant points in the universe, acting as cosmic shortcuts. However, wormholes are described as unstable and requiring immense gravitational energy, possibly linked to black holes. The concept of 'negative energy' or 'antigravity' might be needed to stabilize them, a phenomenon currently only observed at microscopic scales (Casimir effect).

Profiter de l'expansion de l'Univers (Exploiting the Expansion of the Universe)

Another theoretical method discussed is leveraging the expansion of the universe itself. The article explains that the space between distant regions expands, causing them to recede from each other at speeds proportional to their distance. Extraterrestrials might be able to create localized 'expansion waves' around their vessels, effectively surfing these waves to achieve superluminal travel relative to local space, while still adhering to the speed of light locally.

Téléportés à la vitesse de la lumière (Teleported at the Speed of Light)

This section examines the concept of teleportation, as popularized by Star Trek. It involves converting matter into light particles (photons) to travel at light speed and then reconstructing the original form at the destination. However, the article calculates that the amount of information required to reconstruct a human body (position and energy state of each atom) is astronomical, requiring immense energy (equivalent to 1,500 megaton hydrogen bombs) and time (millions of years) for transmission and reconstruction, raising questions about the transmission of consciousness.

Et s'ils étaient déjà là ? (And if they were already here?)

This article explores the possibility that UFOs are already present, perhaps using advanced, yet terrestrial, technology. It discusses the characteristics often attributed to UFOs: silent, luminous, and capable of defying gravity. The case of Trans-en-Provence is detailed, where a witness reported a disc-shaped object landing, leaving a circular trace, and altering the local vegetation. The article suggests that some phenomena might be explained by advanced propulsion systems, possibly derived from technologies used in submarines or other covert operations.

Non identifié... mais parfaitement explicable ! (Unidentified... but perfectly explainable!)

This piece presents a 1965 photograph of a UFO from Saint Georges, USA, suggesting that such sightings might have perfectly 'terrestrial' explanations. It reiterates the GEPAN (Group for the Study of Unidentified Aerial Phenomena) findings regarding the Trans-en-Provence case, noting the modification of the vegetation's photosynthetic system, which suggests a significant physical impact from the object.

Recurring Themes and Editorial Stance

The magazine adopts a scientifically grounded yet open-minded approach to the UFO phenomenon. It acknowledges the cultural fascination with extraterrestrials and the scientific discoveries that fuel speculation, such as exoplanets. However, it consistently grounds the discussion in known physics, highlighting the immense challenges of interstellar travel and the limitations imposed by the speed of light. While exploring theoretical concepts like wormholes and warp drives, it emphasizes their speculative nature and the vast technological gap between current human capabilities and those required for such feats. The editorial stance appears to be one of cautious inquiry, separating scientific plausibility from pure fantasy, and suggesting that some reported phenomena might have mundane explanations, while leaving the door open for truly advanced extraterrestrial intelligence operating beyond our current understanding of physics.

Title: DOSSIER
Issue: 947
Date: August 1996
Publisher: Science & Vie
Country: France
Language: French

UFO Propulsion Explained: The MHD Theory

The article "OVNIS" from the "DOSSIER" section of Science & Vie magazine, issue 947 (August 1996), explores the theory of magnetohydrodynamics (MHD) as a potential explanation for the propulsion of Unidentified Flying Objects (UFOs).

The Core Concept of MHD Propulsion

Jean-Pierre Petit, a French specialist in MHD, proposed a theory that encompasses the characteristics observed in UFOs, such as luminous halos. Unlike conventional propulsion systems used in boats and airplanes, which push fluids (water or air) backward to move forward, the MHD system works in reverse: the fluid itself pushes the craft.

Overcoming the Sound Barrier

When an aircraft moves through the atmosphere, it encounters air molecules. Conventional systems, like turbines, expel these molecules backward. This process creates a build-up of molecules, or a "front of energy," at the front of the aircraft, which tends to slow it down. The elasticity of air normally dissipates this concentrated energy. However, when an aircraft reaches the speed of sound (331 m/s), the air's elasticity cannot dissipate the energy quickly enough, leading to the "sound barrier" and the characteristic "bang."

MHD propulsion offers a solution. In this system, the air layers surrounding the craft are ejected backward by a magnetic force, creating a kind of wind. This results in an accumulation of air molecules at the rear, pushing the vessel forward. Simultaneously, a vacuum is created at the front, which pulls the craft. This eliminates the energetic barrier that opposes progression, allowing the flying saucer to exceed the speed of sound without producing a sonic boom. Furthermore, this process is magnetic rather than mechanical, generating only a slight whistling sound from the expelled molecules.

The Role of Magnetic Fields and Ionization

The magnetic field generated at the surface of the craft is responsible for moving the air. Charged particles (electrons and ions) within the air are affected by this magnetic field. For example, approaching a magnet to a television screen distorts the image because the screen is made of electrons.

While air molecules (like O2 and N2) are not inherently charged, they can be made so by ionizing the atmosphere – essentially stripping electrons from them. This ionization is achieved through a magnetic field generator and an ionizer, which could involve an electric field or pulsed microwaves. For underwater applications, such as in seawater which naturally contains ions, an ionizer might not be necessary.

Luminous Phenomena and Other Effects

When the air surrounding the craft is ionized, it becomes fluorescent. This phenomenon could explain witness descriptions of UFOs as "flying light balls."

The strong magnetic field produced by the MHD engine might also be responsible for other observed effects, such as causing car engines to stall, inducing malaise in humans, or causing cellular alterations in plants. These observations have led to speculation that UFOs might be secret, experimental craft developed by terrestrial armies.

Recurring Themes and Editorial Stance

The article presents a scientific hypothesis, magnetohydrodynamics, as a plausible explanation for UFO phenomena, particularly their propulsion and luminous aspects. It highlights the work of Jean-Pierre Petit and contrasts the proposed MHD system with conventional physics. The magazine's stance, as indicated by the footnote (2), is that while they acknowledge Petit's scientific contributions, they do not follow his conviction about the presence of extraterrestrials on Earth, suggesting a critical yet open approach to the subject.