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Yet we will continue to be inundated constantly, even here on FreeRepublic, with new “science” reports claiming to have discovered another “earth-like” planet somewhere in the universe.

But almost always those reports contain findings of planets - light years away and observable only with far distant reading astronomical instruments - that the “scientists” and their reporters refer to as “earth-like” merely with barely one or two valiables that proximate such measures for earth - such as inhabiting a “habitable” zone of a star and the size of the planet.

But:

1. Orbiting a star with sufficient “metallicity,” necessary for the formation of terrestrial rather than gaseous planets?

2. Orbiting a star that is orbiting a “habitable zone” within a galaxy, and not closer to the center of a galaxy, where radiation and the presence of wandering planetoids make life there unlikely?

3. Orbiting a sun that is in a disk-shaped spiral galaxy rather than in an elliptical (spheroid) galaxy?. Spiral galaxies are thought to be the only type capable of supporting life.

4. Orbiting around a star in an almost perfect circle (like earth days) rather than the more common “eccentric” (elongated) ellipse? Steep elliptical orbits take a planet relatively close to and then relatively far from a sun, with great consequences for warmth and light. Earth’s stable, nearly circular orbit around the sun keeps our distance from it relatively constant, and hence the amount of heat and light does not vary tremendously.

5. Orbiting in a star system with outer massive gas planets (like Jupiter and Saturn) that can attract and catch many wandering asteroids and comets and generally keep them from hitting planets closer to the star (like with Earth)?

6. Orbiting in a solar system with asteroid belts that also keep a lot of destructive flying rock in a stable orbit and away from other planets?

7. A planet with a molten core that creates a magnetic field that holds radiation belts in place; belts that protect the surface of a planet (like Earth) from the most harmful rays of it’s star?

8. A planet with ongoing volcanism that plays a role in generating an atmosphere, and together with seismic and plate tectonic activity is cycling rich minerals widely?

9. Orbiting just the right kind of star, putting out a fairly steady amount of energy? Other types of stars are more variable in their output and this variance can utterly destroy life or cause it to be unsustainable due to the extremes.

10. A planet with a fairly rapid rotation (like erth) that reduces the daily variation in temperature and also makes photosynthesis viable because there is enough sunlight all over the planet?

11. A planet tilted on its just enough relative to its orbital plane to allow seasonal variations that help complex life, but not so tilted as to make those variations too extreme (like earth)?

12. A planet with a moon that causes tides that are just strong enough to permit tidal zones (a great breeding ground for diverse life) but not so severe as to destroy life?

Do these often “we found anothter ‘earth-like planet’ “ reports refer to what all really makes a planet “earth-like”?

No. They are all click bait seeking groupies from which they can tell their advertisers that their ads are worth it.