Centauri Dreams 3 Jun 2021, 14:06 UTC You can blame H. G. Wells’ The Time Machine for my interest in the Earth’s far future. That swollen red Sun at the end of the novel created vivid ‘end of the world’ scenarios for me as a boy, and later I would learn that outer planets or moons around a G-class star might turn habitable once it became a red giant. But it would only be in the last few years that I learned how robust the investigations into white dwarf systems — the fate of a red giant — have become, and now we’re finding out not only that such stars can retain planets, but can conceivably create new ones through an emerging disk packed with the pulverized dust of remnant materials like asteroids.
Universe Today 2 Jun 2021, 22:25 UTC A number of missions are destined for the Moon before this decade is over. In addition to the Artemis Program, the European Space Agency (ESA), the China National Space Agency (CNSA), Roscosmos, and other space agencies have some ambitious plans of their own. These include sending robotic missions to characterize the local environment, scout out resources, and pave the way for permanent human outposts.
Centauri Dreams 2 Jun 2021, 17:01 UTC The first thing to say about the image below is that it fills me with anticipation for the imagery that Europa Clipper will acquire when it travels to the Jovian moon later this decade (arrival in 2030, according to current planning). This is a Galileo image taken in 1996, the subject of intense study, as have been all the Europa images, ever since. How much interaction does Europa’s subsurface ocean have with the icy crust? We can’t say for sure how much is going on now, but images like these show how much fracturing and re-formation there has been in the past. In any event, fresh data from Europa Clipper should give us entirely new insights.
Scientific American 2 Jun 2021, 13:45 UTC Despite the best efforts of scientists eager to study Earth’s sister world, U.S. efforts to send a dedicated spacecraft to Venus have languished. An imminent announcement could decide whether it will be years—or decades—before we go back.
Centauri Dreams 1 Jun 2021, 18:31 UTC Back in the 1990s, when the first exoplanet detections were made, the best possible targets for radial velocity searches were what we now call ‘hot Jupiters.’ Radial velocity looks at the Doppler shift of light as a star moves first towards us, then away, tugged by the invisible planet. A massive Jupiter in a tight orbit tugged maximally, and quite often, because its orbit could be measured in mere days or weeks. It was purely selection effect, but it seemed that such planets were common, until we began to discover just how many other kinds of worlds were out there.
EarthSky Blog 31 May 2021, 14:20 UTC Clouds on Mars are rare. With its thin atmosphere and scarcity of water, it’s not often there are the right conditions for clouds to form. The best time for clouds on Mars is during its coldest months near the Martian equator. Space scientists using the Mars Curiosity rover, which has been exploring the red planet since 2012, released these images of cloudy Martian skies on May 28, 2021.
SPACE.com 31 May 2021, 13:56 UTC Solar activity refers to the state of the sun’s magnetic field and associated phenomena: sunspots, flares, solar wind and coronal ejections. During periods of minimal solar activity, such events are often uncommon and weak. During solar maximum, they’re at their strongest and most frequent. Magnetic field fluctuations on the sun can happen on drastically different timescales, ranging from seconds all the way to billions of years. When astronomers speak of a “slowdown” or a period of quiescence in the sun’s activity, it doesn’t mean the sun will stop shining, but that there’s a slowdown in activity.