Billions of years ago when the Red Planet was young, it appears to have had a thick atmosphere that was warm enough to support oceans of liquid water – a critical ingredient for life. The animation shows how the surface of Mars might have appeared during this ancient clement period, beginning with a flyover of a Martian lake. The artist’s concept is based on evidence that Mars was once very different. Rapidly moving clouds suggest the passage of time, and the shift from a warm and wet to a cold and dry climate is shown as the animation progresses. The lakes dry up, while the atmosphere gradually transitions from Earthlike blue skies to the dusty pink and tan hues seen on Mars today.
Dark matter filament studied in 3D for the first time! NASA/ESA Hubblecast 58: “Caught in the Cosmic Web – Dark Matter Structure Revealed by Hubble Space Telescope”.
In this episode of the Hubblecast, Joe Liske (aka Dr J) shows how a team of astronomers has used Hubble and a battery of other telescopes to discover the secrets of massive galaxy cluster MACS J0717. They have found that an invisible filament of dark matter extends out of the cluster. This is our first direct glimpse of the shape of the scaffolding that gives the Universe its structure.
This animation, produced in 1999, shows an artist concept of NASA’s Upper Atmosphere Research Satellite, launched in 1991. UARS measured chemical compounds found in the ozone layer, wind and temperature in the stratosphere, as well as the energy input from the sun. Together, these measurements helped define the role of Earth’s upper atmosphere in climate and climate variability. The 35-foot-long, 15-foot-diameter UARS was decommissioned on Dec. 14, 2005. (no audio)
From double sunrise to double sunset the show goes on, always changing.
A planet with two suns is a familiar concept from science fiction. However, the evidence for the existence of circumbinary planets—those that orbit around both members of a stellar binary—has been limited. A few good cases have been made for circumbinary planets based on the timing of stellar eclipses [see, e.g., (1–3)], but in no previous case have astronomers obtained direct evidence of a circumbinary planet by observing a planetary transit (a miniature eclipse as the planet passes directly in front of a star). Detection of a transit greatly enhances confidence in the reality of the planet and provides unusually precise knowledge of its mass, radius, and orbital parameters (4).
Here we present the detection of a transiting circumbinary planet around a binary star system based on photometric data from the NASA Kepler spacecraft. Kepler is a 0.95-m space telescope that monitors the optical brightness of about 155,000 stars within a field encompassing 105 square degrees in the constellations Cygnus and Lyra (5–8).