In this rare image taken on July 19, 2013, the wide-angle camera on NASA’s Cassini spacecraft has captured Saturn’s rings and our planet Earth and its moon in the same frame. It is only one footprint in a mosaic of 33 footprints covering the entire Saturn ring system (including Saturn itself). At each footprint, images were taken in different spectral filters for a total of 323 images: some were taken for scientific purposes and some to produce a natural color mosaic. This is the only wide-angle footprint that has the Earth-moon system in it.
The dark side of Saturn, its bright limb, the main rings, the F ring, and the G and E rings are clearly seen; the limb of Saturn and the F ring are overexposed. The “breaks” in the brightness of Saturn’s limb are due to the shadows of the rings on the globe of Saturn, preventing sunlight from shining through the atmosphere in those regions. The E and G rings have been brightened for better visibility.
Earth, which is 898 million miles (1.44 billion kilometers) away in this image, appears as a blue dot at center right; the moon can be seen as a fainter protrusion off its right side. An arrow indicates their location in the annotated version. (The two are clearly seen as separate objects in the accompanying narrow angle frame: PIA14949.) The other bright dots nearby are stars.
This is only the third time ever that Earth has been imaged from the outer solar system. The acquisition of this image, along with the accompanying composite narrow- and wide-angle image of Earth and the moon and the full mosaic from which both are taken, marked the first time that inhabitants of Earth knew in advance that their planet was being imaged. That opportunity allowed people around the world to join together in social events to celebrate the occasion.
This artist’s concept shows a possible model of Titan’s internal structure that incorporates data from NASA’s Cassini spacecraft. In this model, Titan is fully differentiated, which means the denser core of the moon has separated from its outer parts. This model proposes a core consisting entirely of water-bearing rocks and a subsurface ocean of liquid water. The mantle, in this image, is made of icy layers, one that is a layer of high-pressure ice closer to the core and an outer ice shell on top of the sub-surface ocean.
A model of Cassini is shown making a targeted flyby over Titan’s cloudtops, with Saturn and Enceladus appearing at upper right.
The model, developed by Dominic Fortes of University College London, England, incorporates data from Cassini’s radio science experiment.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA’s Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radio science team is based at Wellesley College, Wellesley, Mass.
The close proximity of COROT-7b to its star (just 1.6 million miles) keeps it gravitationally locked in place just as the moon is to the Earth, meaning the same side of always faces the star. As such, it stays very, very hot there (about 4,220 degrees Fahrenheit). That kind of heat vaporizes rocks, and that’s exactly what happens on COROT-7b. Using computer modeling, the team at Washington ran through four different scenarios with four different starting compositions (since the exact makeup of the planet is unknown) with the same result each time.
Just as water vaporizes in our atmosphere only to condense at higher, cooler altitudes and fall back to the Earth as rain, so do the sodium, potassium, silicon monoxide, magnesium, aluminum, calcium and iron of COROT-7b. When they condense, however, they condense into rock clouds that rain little pebbles of different types of rocks. What’s more, the type of rock is dependent on altitude. The atmosphere gets colder the higher up the rock vapor goes. Since each rock or mineral has a different boiling point, the materials with the highest boiling points will condense out at lower altitudes, while the ones with lower boiling points can rise higher as vapor before condensing back into rocks.
Uranus, photographed by the Hubble Space Telescope through various filters. Of note is what appears to be a cloud centre-right; Uranus looked almost completely featureless in Voyager’s pictures, but at least at some wavelengths, there is something going on in the atmosphere. The rings are also clearly visible in the last few frames (892nm methane filter). Assuming I made no interpretational blunders with HORIZONS data, Miranda is the small moon at the bottom of the frame, and Ariel is near the top.
Last week, this Tumblr went on a Hubble binge. This week: Keck! (Yes, in a desperate bid to keep the daily updates going, I’ve started using ground-based observations.) We start with Jupiter, seen from the Keck Observatory at Mauna Kea in Hawaii on 4 June 2010, at wavelengths of 1.95-2.3 microns (i.e., infrared). The gif covers about 30 minutes of real time. (Program ID C304N2L.)
Plants under the confocal microsope:Seeing is believing.
The last twenty years have seen a revolution in the application of optical techniques to the study of biological systems. Largely due to the development of highly specific fluorescent labelling methods, and optical techniques such as confocal laser scanning microscopy.
Different coloured fluorescent proteins are used routinely to decorate cells and subcellular structures in living tissues, and optical sectioning techniques allow visualisation of these labels.Meaning we can observe the different parts of any tissue and watch their movements.