Jupiter And Beyond The Infinite…

Resembling our Moon, and with a similar atmosphere, Mercury has enough activity in its interior to generate a small magnetic field. Join guides Denton Ebel and Carter Emmart for an up-close examination of our solar system’s smallest planet. 

Saturn’s Moon, Enceladus, Is Our Closest Great Hope For Life Beyond Earth

“Cassini provided scientists with a wealth of data about Enceladus’ surface and the composition of its powerful plumes. This data showed evidence of a deep saltwater ocean with an energy source beneath Enceladus’ surface. The presence of water, warmth, and organic molecules are the necessary requirements for sustaining life as we know it. Water is proven to exist, while the tidal forces from Saturn provide the necessary heat. Based on observations of other bodies in the Solar System, Enceladus likely contains the raw ingredients for life as well. The suspected existence of all three hints at the possible presence of the precursors to amino acids in this vast subsurface ocean. Should we find extraterrestrial life on Enceladus – or in the geyser-like plumes erupting into space – the implications are almost incomprehensible.”

When you think about life beyond Earth, you likely think of it occurring on a somewhat Earth-like planet. A rocky world, with either a past or present liquid ocean atop the surface, seems ideal. But that might not even be where life on Earth originated! Deep beneath the Earth’s surface, geologically active hydrothermal vents currently support diverse colonies of life without any energy from the Sun. Saturn’s icy moon, Enceladus, has a subsurface ocean unlike any other world we’ve yet discovered. The tidal forces of Saturn itself provide the necessary heat, and also create cracks in the Enceladean surface, enabling massive geysers. This subsurface ocean rises hundreds of kilometers high, regularly resurfaces the world with a coat of fresh ice, and even creates the E-ring of Saturn. But most spectacularly, it may house actively living organisms, and could be the next-best world for life, after Earth, in the Solar System today.

Come get the full story on Enceladus, and welcome Starts With A Bang’s newest contributor, the remarkable Jesse Shanahan!

Maria Mitchell - Scientist of the Day

Maria Mitchell, an American astronomer, was born Aug. 1, 1818, in Nantucket. Mitchell was the first professional woman astronomer in the United States and a role model for generations of aspiring women scientists. She was trained by her father, a school-teacher, and had the extreme good fortune to discover a comet in 1847. Not only was she the first to see the comet, she also had the mathematical skill to calculate its orbit. Her feat won her an international gold medal from the Danish government, the first such recognition for any American woman, and eventually, the professorship of astronomy at Vassar College, also the first such position for any woman. (It is probably of interest to some of this reading audience that, before she became famous, Mitchell spent 17 years as a librarian on Nantucket.) Mitchell was admitted to various male bastions, such as the American Academy of Arts and Sciences in Boston (the only woman so honored until the 20th century), but she decided early on that, instead of trying to show men that women could be good scientists, she would spend her life showing young women that they could be good scientists. She seems to have done a superb job at this task, becoming a legendary teacher at Vassar. Antonia Maury, a noted astronomer at Harvard, was one of her pupils. The lovely albumen print portrait of Maria above is at Harvard.

In 1863, Matthew Vassar, the founder of Vassar College, personally commissioned a telescope for Mitchell from Henry Fitz, a well-known New York telescope builder. With a lense 12 inches in diameter, it was second among American telescopes only to the great refractor at Harvard (see second image above). The telescope is now in the National Museum of American History in Washington. Vassar also built an observatory for Maria; a period photo can be seen above, just below the Fitz refractor.

The small telescope that Mitchell used to discover the Nantucket comet is now mounted in her childhood home on Vestal Street (see last photo above), across from the headquarters of the Maria Mitchell Association, the group her descendants founded in 1908 to continue Mitchell’s lifelong passion for the natural sciences and science education.

Dr. William B. Ashworth, Jr., Consultant for the History of Science, Linda Hall Library and Associate Professor, Department of History, University of Missouri-Kansas City

Great collection of astronomical articles and pictures

How do we know light is a wave?

Before I answer this question, I’ll need to briefly go over a wave property called superposition. Basically, superposition is the idea that two waves can be in the same position at the same time, and interfere with each other:

When the two waves add to each other and make a larger wave, we call this constructive interference. When the waves cancel each other out, we call this destructive interference. 

Now we’re going to move on to the Double Slit Experiment. Basically, you shine a beam of light at a piece of metal, cardboard, etc with two slits in it, with a surface behind it where you can see the light hit it. 

If light is a wave, what we’d expect to see would be an interference pattern created by the light from the first slit interfering with light from the second slit, which is exactly what we see. It’s a pattern of constructive interference (brighter regions) and destructive interference (darker regions), looking like this:

These images are helpful:

that is how we know light acts as a wave!!

Comet lander Philae wakes up: How it happened and what’s next

By Lauren Raab

Philae, the first spacecraft to land on a comet, surprised and delighted scientists this weekend by waking up and reestablishing contact with Earth, seven months after running out of power. It “spoke” for more than a minute, according to the European Space Agency, and it’s expected to be able to continue gathering information and sending it home.

Here’s a look at what the lander has done so far and what will happen next.

Continue Reading.

Starry Night,

Vincent Van Gogh

Observing the Skies Above by Kirby Wright on Flickr.

tfw your inactive blog gets a whole bunch of notes out of nowhere and you wonder if you could ever bring it back to life

Space Station View of the Full Moon

Credit: NASA & ISS