Opinautics p.2

Magazine available on eBay

9/21/20246 min read

SEARCHING ON INTERNET

Searching the August 1982 Sky & Telescope magazine article on the Internet, a few searchable databases were searched. GPT OPENAI Chat was asked with this prompt, “Which libraries in the United States have Sky & Telescope magazine, august 1982?” Then the chat suggested to query these web sites:

GPT Chat query Bing Microsof. It gave this options:
1. Sky & Telescope.
2. Go to a local library
3. Sky & Telescope: All 70 Years. They offer a DVD collection of all issues from 1941 to 2009.
Name Index to Sky & Telescope. Vol. 1., No. 1 (Nov. 1941) to Vol. 108, No. 6 (December 2004) Compiled by Kevin Krisciunas. Texas A & M University, Department of Physics, College Station, Texas. E-mail: krisciunas@physics.tamu.edu.
Sky & Telescope Magazine. It shows only to July/August 2006 issue, which is at the end of the list of the 24 webpage ( see the list at the bottom).
Magazine Archive and Index Help. You can find the index of published magazines.
ShopAtSky.Com Apparently only issues since January 2020 are listed.

FINALLY... This is the magazine, it was available in eBay.

There is a short description of the article:

Sky and Telescope Magazine 1982 August Moon Galaxies Astronomy Vintage S7

SOME REMINDERS FOR OPINAUTS

🚀 Exploring Science Fiction

The idea for this blog has been simmering for some time, until something came along that helped make this initiative a reality. Among the variety of podcasts I usually listen to, this is one of my favorites, the Punto Bernal Podcast. This podcast is made by Antonio Bernal González, science popularizer of the Fabra Observatory, in Barcelona, Spain. And Jorge Zuluaga, associate professor at the Institute of Physics of the University of Antioquia, Medellín, Colombia.

In minute 43:33 of an episode called Monsters at the Center of Galaxies, Antonio mentions that navigation near a black hole is called openautics, which appeared in the magazine Sky & Telecospe 1982. When we searched the internet we were surprised to find that there is not much information about it, a few references, but no access to the document. That's how this adventure began: we found the magazine on eBay.

So, here is just a short review

For the purpose of sharing some of the key ideas from the article, without infringing copyright laws, I list the following:

There are three important characteristics for determining different types of black holes: spin, mass, and charge. This is crucial because it helps identify which black holes are potentially "navigable."
Uncharged black holes, such as Kerr black holes, generate an ergosphere with a pumpkin-like shape, covering the event horizon or singularity. The Kerr black hole is more complex because it has spin, while the Schwarzschild type has neither charge nor rotation. Approaching a Schwarzschild black hole is highly inadvisable because one would encounter the event horizon directly. In contrast, a Kerr black hole presents a highly risky—but theoretically possible—way to approach it.
A Kerr black hole could be reached via the axial axis perpendicular to the rotation axis. As one attempts to enter the singularity, it becomes increasingly difficult to approach the center due to the equatorial forces created by spacetime dragging within the ergosphere.
Since there is no hope of returning, the best possible outcome would be to find a future segment to move toward. If the "opinauts" are lucky, they might find a future similar and hopefully close to the universe they left behind.

The author presents one of the Penrose diagrams, where segments or regions of time are represented as different rhombuses stacked underneath. These spacetime segments correspond to universes from the ultra-past, infra-past, present, future, and ultra-future, as well as other universes and anti-universes. However, all these possibilities do not appear in every black hole; rather, they depend on the spacetime configuration resulting from the astrophysical characteristics of each one.

In the magazine, the author presents these diagrams as beautifully colored rhombuses. One of them conveys the idea of a spiral formed by rhombuses or a spiny wand created by the union of small squares rotated 45°. From these configurations, information is being emitted to the observing "opinaut"—events that have happened, are happening, and will happen—light coming from ultra-pasts and/or ultra-futures. 🚀

Then, I asked Copilot to verify and complement this information, and here’s the result (as the black hole's images and explanations of them in this post):

Copilot Chat:

Uncharged black holes, such as Kerr black holes, generate an ergosphere that extends beyond the event horizon, this type of black hole is more complex because it has spin, causing spacetime dragging. A Schwarzschild black hole offers no possibility of escape once the event horizon is crossed—any object entering is doomed to the central singularity. Kerr black holes, however, have a different structure due to their rotation. Though extremely dangerous, some theoretical models suggest that, under specific conditions, a spacecraft could use this dragging effect to perform certain maneuvers.
To approach a Kerr black hole, the best theoretical option is to do so along the rotation axis rather than the equator. The external ergosphere allows for some exploitation of these effects, but the closer one gets to the event horizon, the harder it becomes to avoid inevitable downfall.
Regardless, crossing the event horizon of any black hole means a one-way journey. In some relativistic models, certain rotating black holes might lead to an alternative future due to the geometry of spacetime within them. However, in practice, anything entering would experience extreme gravitation and severe spacetime distortions, making any communication with the outside world impossible.

Additional Black Hole Types:

Reissner-Nordström: Similar to Schwarzschild but with an electric charge, which affects the event horizon’s structure and might create an additional inner horizon.

Kerr-Newman: The most complex version, combining rotation and charge, leading to an even more dynamic structure.

Supermassive: Found at the center of galaxies, these can reach millions or billions of solar masses.

Primordial: Hypothetical black holes, possibly very small, formed during the early moments of the universe.

Figure 1. "Figure 3. Sketch of a Kerr black hole, with its two horizons and the ring singulatrity." (Romero, G. E., 2014, p.12)

Figura 2. Penrose diagrams of a infinite Minkowski universe, axis horizontal u, axis vertical v.

A Schwarzschild Black Hole

🌀This type of black hole is the simplest, with no charge or rotation, and a perfectly spherical event horizon.

Learn more

A Kerr Black Hole

Penrose diagram of Schwarzschild's black hole. JILA a joint instute of CBU and NIST.

Penrose diagram of Kerr's black hole. JILA a joint instute of CBU and NIST.

🌀In contrast, this type of black hole rotates on its axis. Due to this rotation, its event horizon is distorted, forming more of an oval shape rather than a perfect sphere. Additionally, it has an extra region called the ergosphere, where spacetime itself is dragged due to its rotation. This effect creates a more dynamic image, with motion lines and pronounced spatial distortions.

REFERENCES

Romero, G. E. (2014). Philosophical Issues of Black Holes. http://arxiv.org/abs/1409.3318

Sheldom, E. (1982). Opinautics: A Matter of Much Gravity. Sky and Telescope, august 1982, vol 62 N°. 2.

CYBERGRAPHY

[1] Copilot Microsoft: https://copilot.microsoft.com/

[2]. Penrose_diagram.svg: https://en.wikipedia.org/wiki/Penrose_diagram