For almost 30 years now, the Hubble Space Telescope has transformed how we see the cosmos. In terms of scientific output as well as making visible the splendors of the sky above us, the Hubble has been arguably the most consequential telescope ever to peer into space. To commemorate 30 years of Hubble science and …
Continue reading "Sparkling Gifts From the Hubble Space Telescope, Thirty Years Into Its Mission"
When our sun was young, it was significantly less luminous and sent out significantly less warming energy than it does now. Scientists estimate that 4 million years ago, when the sun and our solar system were 500 million years old, the energy that the sun produced and dispersed was about 75 percent of what it …
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"
What started as a stunning announcement that the chemical phosphine -- a known byproduct of life -- had been found in the clouds of Venus and could signal the presence of some lifeform has now been strongly critiqued by a number of groups of scientists. As a result, there is growing doubt that the finding, …
The search for water on the moon has produced a discovery of tiny molecule-sized perhaps widespread amounts of H20 in a sunlit lunar crater. The water is not in a liquid or ice or gaseous form, but rather apparently contained (and protected) inside glass beads formed when micrometeorites hit the surface. The detection was made …
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?"
The first images of the sun from the European Space Agency/NASA’s Solar Orbiter have been released and are stupendous. They are the closest photos ever taken of the star that we orbit, and have already revealed some fascinating features that nobody knew existed. Launched early this year, the spacecraft completed its first close pass of …
For space scientists of all stripes, few goals are as crucial as bringing pieces of Mars, of asteroids, of other planets and moons back to Earth for the kind of intensive study only possible here. Space missions can, and have, told us many truths about the solar system, but having a piece of Mars …
Many Worlds 