Like people, stars are found in all colors and sizes. They can range from small, sassy red dwarfs to giant blue beasts. In fact there are seven main types of stars, grouped by their apparent colors (and thus temperatures) and classified as O, B, A, F, G, K, or M in order of hottest to coolest. (Learn more about that here.) The video above, released by The Royal Observatory in Greenwich, England, gives a brief life history of three of the most common types of stars found in our galaxy: blue O stars, red M dwarfs, and yellow G stars—the latter of which being the class of our own Sun. It’s really fun, cute, and educational—check it out, and also find more videos on The Royal Observatory’s Vimeo page.
It’s all downhill from here! (Well not really, but it was for a little while when Opportunity was at the top of that hill!) The image above is a mosaic I assembled from six color-composites, each made from three separate images acquired in near-infrared, green, and near-ultraviolet color wavelengths on April 21, 2017 (mission sol 4707). It’s been adjusted to appear in approximate true color to what the scene might look like to a human standing on Mars. The view shows a ridge called “Rocheport” located on the western rim of Endeavour Crater (the interior of which would be toward the right in this image) which was the final segment of Opportunity’s last target region of exploration, Cape Tribulation. Opportunity’s wheel tracks can be seen at the bottom center, heading back up the ridge and zig-zagging toward the top (detail below).
SPACE NEWS FLASH: On Wednesday, April 19, the asteroid 2014 JO25 will pass by Earth, coming as close as about 1.1 million miles at 12:24 UTC (8:24 a.m. EDT / 5:24 a.m. PDT). Yes, this asteroid is fairly large—just under half a mile across—and is traveling very fast—about 21 miles a second— BUT even so it poses no danger to Earth as 1.1 million miles is still over four and a half times the distance to the Moon…and it’s simply not going to get any closer than that.
It’s. Just. Not.
Using ground-based telescopes, an international team of astronomers has identified an atmosphere around the exoplanet GJ 1132b. Orbiting a red dwarf star a mere 39 light-years away this world is only about half again as large and massive as Earth, making it the smallest exoplanet to be discovered thus far with an atmosphere.
Unfortunately that likely means that although GJ 1132b is Earth-sized it’s not Earth-like. In order to even be detected in the manner that it was the atmosphere must be extremely thick, making this exoplanet more similar to Venus than Earth.
“An atmosphere that we would think of as Earth-like would be completely invisible to these observations, and to all other currently existing telescopes,” said Tom Louden, a physicist at the University of Warwick in Coventry, England (who wasn’t involved in the study.)
One of the favorite allegations by those who continue to be skeptical of the Apollo moon landings is that there are no stars visible in the photographs taken by the astronauts while they were “supposedly” on the Moon. Now while there’s a rather short but succinct list of why that’s the case (and feel free to review those reasons here) the truth is that there ARE stars visible in photographs taken from the Moon—photographs taken in ultraviolet light during the penultimate Apollo 16 mission in April of 1972.