Comet Lander Philae Wakes Up: How It Happened And What’s Next

Observing the Skies Above by Kirby Wright on Flickr.

Image of Saturn taken by Cassini spacecraft in October 28, 2016.

Credit: NASA / JPL / Cassini

Saturn and Jupiter You can see Jupiter’s moon, Io, casting a shadow onto the gas giant.   Credit and Source:  nomorelickfoot 

Cometary Globules

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

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!

This is what a comet looks like, up close and personal.

PHOTOS FROM AN ALIEN WORLD.

I am so excited I can’t even. Source: ESA’s Flickr feed.

The Drake Equation (sometimes known as: Green Bank equation or the Green Bank Formula)

The Drake Equation is a formula that may calculate the possibility of contactable extra-terrestrial alien species. 

Proposed by Frank Drake in 1961, the Drake Equation is a probability argument that would estimate how many contactable, active and communicable alien species there are in our Milky Way. 

The Drake Equation is, as follows;

N = R* • fp • ne • fl • fi • fc •  L.

In this equation, N =  the number of civilizations in our galaxy with which communication might be possible. 

R* = the average rate of star formation in our galaxy.

fp = the fraction of those stars that have planets

ne = the average number of planets that can potentially support life per star that has planets

fl = the fraction of planets that could support life that actually develop life at some point

fi = the fraction of planets with life that actually go on to develop intelligent life (civilizations)

fc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into space

L = the length of time for which such civilizations release detectable signals into space

The Drake Equation acts as a summary of which we can expect to communicate (if at all) with those who are extra-terrestrial.  The last four parameters: fl, fi, fc and L, are not known and are very hard to estimate, with values ranging over many orders of magnitude. 

Therefore it is not a direct measurement of when we will communicate but a roadmap towards creating and estimating the means necessary to communicate with our space buddies. 

Sean Goebel - Mauna Kea Heavens 2 | gif by FD