knowledgethroughscience:

Attention stargazers - Mercury, Jupiter and Venus appear very close together in the sky, May 24-26, 2013.

Three planets are coming together in the evening sky at the moment, putting on a celestial show that won’t be seen again for more than a decade.

“The view should be best about 30 to 45 minutes after sunset,” said Alan MacRobert, a senior editor at Sky & Telescope magazine. Find out how to spot Jupiter, Venus and Mercury.

thescienceofreality:

NASA Probe Observes Meteors Colliding with Saturn’s Rings.

“NASA’s Cassini spacecraft has provided the first direct evidence of small meteoroids breaking into streams of rubble and crashing into Saturn’s rings. 

These observations make Saturn’s rings the only location besides Earth, the moon and Jupiter where scientists and amateur astronomers have been able to observe impacts as they occur. Studying the impact rate of meteoroids from outside the Saturnian system helps scientists understand how different planet systems in our solar system formed. 

The solar system is full of small, speeding objects. These objects frequently pummel planetary bodies. The meteoroids at Saturn are estimated to range from about one-half inch to several yards (1 centimeter to several meters) in size. It took scientists years to distinguish tracks left by nine meteoroids in 2005, 2009 and 2012. 

Results from Cassini have already shown Saturn’s rings act as very effective detectors of many kinds of surrounding phenomena, including the interior structure of the planet and the orbits of its moons. For example, a subtle but extensive corrugation that ripples 12,000 miles (19,000 kilometers) across the innermost rings tells of a very large meteoroid impact in 1983.”

Read more…

So cool…I wish OUR planet had rings…

Happy Anniversary, Hubble!

This year marks Hubble’s 23rd year of observing! In celebration, the space telescope nabbed an image of the Horsehead Nebula, also known as Barnard 33. You can read more about the nebula, and the anniversary, here.

sciencesoup:

Badass Scientist of the Week: Caroline Herschel

Caroline Herschel (1750-1848) grew up in Germany, as the daughter of a professional musician. Her father gave all his children a broad basic education in art, music, and science. His wife did not approve of educating her daughter, and when her father died, Caroline’s mother put her to work in the kitchen. Caroline had had several childhood diseases that had left her slightly disfigured, and her mother didn’t think she’d be good enough to marry, so she settled on a life of housework for her daughter.  Meanwhile, one of Caroline’s older brothers, William Herschel, had moved to England, where he was working as a composer and music director, and built telescopes in his spare time. When he found out that his mother had put his sister to work as a servant, he invited Caroline to move in with him in England. She did, and quickly got a successful career as a singer. While Caroline stayed with William, he made a discovery that would change both of their lives. Using a telescope he built himself, William Herschel discovered the planet Uranus in 1781. He was hired by King George III as “King’s Astronomer”, and quit his music career to devote all his time to science. Caroline helped him out, first by cleaning lenses and taking notes, but later with astronomical observations of her own.  She discovered a number of comets, including one that was named after her, and as reward for her work, the state paid Caroline a regular stipend, making her the very first woman to receive a salary for scientific work.

Guest article written by Eva, who writes about scientists/musicians on easternblot.net and on Tumblr as MusiSci

Name That Space Rock by Tim Lillis

I know there’s a difference between a comet, a meteor, and an asteroid…but I don’t always have the specifics on the tip of my tongue. Now I don’t need to know the answer off the top of my head—I can consult this handy-dandy illustration by Tim Lillis.

Via narwhalbot / Flickr, hat tip to Geeks Are Sexy

spaceplasma:

Dynamical Rotational Instability of the First Hydrostatic Core

This animation shows the dynamic rotational instability of the first hydrostatic core. This can occur during the collapse of a molecular cloud to form a star. This animation is from the first three-dimensional calculation ever to follow the collapse of a molecular cloud core all the way to the formation of a star. The calculation has to resolve 7 orders of magnitude in length scale and 17 orders of magnitude in density.

There are several phases of collapse of a molecular cloud before a star is formed (Larson 1969). As the collapse begins, the gas in the cloud remains at the same temperature (isothermal collapse) because the heat generated by compression of the gas can be freely radiated away. However, eventually, as the collapse accelerates, the rate of heating overwhelms the cooling rate and the gas at the centre of the cloud heats up. This occurs at about the same time as the gas at the centre becomes optically thick to the infrared radiation emitted from dust grains. The increasing temperature quickly stops the collapse at the centre of the cloud and a pressure-supported hydrostatic `core’ forms. The size of this object is roughly 5 AU (the radius of Jupiter’s orbit) across.

In the absence of rotation, the core slowly accretes gas that falls on to it from the envelope which is still collapsing isothermally. As it does so, its central density and temperature increase. Eventually, it reachs 2000 K at which point molecular hydrogen (the main constituent) starts to dissociate. This allows the core to begin collapsing again because compressional heating of the gas can be used to dissociate the molecular hydrogen instead of heating up the gas (i.e. it collapses nearly isothermally again). This time the collapse does not stop until a stellar core forms. This is the beginning of the star, although at this stage it only has about the mass of Jupiter.

Credit: Matthew Bate, University of Exeter

This core’s gonna be a star!

sagansense:

What Makes Up the Moon
In 1992, the Jupiter-bound Galileo spacecraft made a pass by our planet’s closest companion, the moon. This mosaic of 53 images shows the different composition of rocks on the moon’s surface. Blue and orange colors represent lava flows, bright pink areas are highlands, and light blue colors indicate recent impact material with the youngest craters showing blue rays extending away from them.

Image: NASA/JPL

I’m a sucker for psychedelic moon photos…