When describing exoplanets that are potentially promising candidates for life, scientists often use the terminology of the "habitable zone." This is a description of planets in orbit where temperatures, as predicted by the distance from the host star, are not too cold for liquid water to exist on a planetary surface and also not to …
Continue reading "How Radioactive Elements May Make Planets Suitable or Hostile to Life"
https://videopress.com/v/U2bToIWU?preloadContent=metadata Artist animation of WD 1856 b orbiting the white dwarf. Due to the tiny size of the white dwarf and close orbit of the planet, the animation is to scale. The slightly inclined orbit means that the planet does not entirely block the white dwarf's light as it transits (Tasker). It has been an …
As we grow more ambitious in our desires to see further and more precisely in space, the need for larger and larger telescope mirrors becomes inevitable. Only with collection of significantly more photons by a super large mirror can the the quality of the "seeing" significantly improve. The largest mirror in space now is the …
Continue reading "Why Not Assemble Space Telescopes In Space?"
Deep inside the rocky planets of our solar system, as well as some solar system moons, is an iron-based core. Some, such as Earth's core, have an inner solid phase and outer molten phase, but the solar system cores studied so far are of significantly varied sizes and contain a pretty wide variety of elements …
Our solar system has but one planet orbiting in what is commonly known as the habitable zone -- at a distance from the host star where water could be liquid at times rather than always ice or gas. That planet, of course, is Earth. But from a theoretical, dynamical perspective, does this always have to …
Continue reading "How Many Habitable Zone Planets Can Orbit a Host Star?"
From the perspective of planet hunters and planet characterizers, a desirable solar system to explore is one that is close to ours, that has a planet (or planets) in the star's habitable zone, and has a host star that is relatively quiet. This is especially important with the very common red dwarf stars, which are …
Continue reading "Close and Tranquil Solar System Has Astronomers Excited"
The image above, courtesy of NASA's Jet Propulsion Laboratory, shows the CubeSat ASTERIA as it was being launched from the International Space Station in 2017. The size of a briefcase, ASTERIA is part of a growing armada of tiny spacecraft being launched around the world and adding an increasingly important (and inexpensive) set of …
Continue reading "For First Time, Tiny CubeSat Locates a Distant Exoplanet"
Earlier last week, NASA put out a release alerting journalists to "an exciting announcement about the agency’s Wide Field Infrared Survey Telescope (WFIRST) mission." Given the controversial history of the project -- the current administration has formally proposed cancelling it for several years and the astronomy community (and Congress) have been keep it going -- …
It was not all that long ago that a "map" of our moon, of Mars, of a large asteroid such as Vesta, of Titan, or of any hard-surfaced object in our solar system would have some very general outlines, some very large features identified, and then the extraterrestrial equivalent of the warning on Earth …
https://videopress.com/v/FRkiDN2V?posterUrl=https%3A%2F%2Fmanyworlds.space%2Fwp-content%2Fuploads%2F2020%2F04%2Fproxima_centauri_c_manysmallrocks.png&preloadContent=metadata Artist impression of Proxima Centauri c. Press "HD" on the player for the best image quality (E. Tasker). The discovery of Proxima Centauri b in 2016 caused a flood excitement. We had found an extrasolar planet around our nearest star, making this the closest possible world outside of our solar system! But despite its …
Continue reading "Have We Photographed Our Nearest Planetary System?"
Many Worlds 
