October 19, 2017

Review: The Strange Affair of Spring Heeled Jack by Mark Hodder.

The science fiction subgenre known as Steampunk has certainly matured in its brief 20+ year existence. True skill in the field has challenged writers to do the historical “foot work” while envisioning an alternate reality and time line that is complete and believable. Which brings us to this weeks’ review of The Strange Affair of Spring Heeled Jack by Mark Hodder, out this September from Pyr Books. [Read more...]

27.06.10: Whitman’s Meteors Identified.

Frederic Church's The Meteor of 1860. (Credit: Federic Church/Judith Filenbaum Hernstadt).

Frederic Church's The Meteor of 1860. (Credit: Frederic Church/Judith Filenbaum Hernstadt).

 

   As the June Bootids ramp up this evening and we brave the swarms of mosquitoes for a chance fireball sighting, consider the following tale. A historical mystery concerning a unique meteor precession has been solved. Recently, the editor of Sky & Telescope Roger Sinnott teamed up with professors and students at Texas State University to solve the mystery of Walt Whitman’s meteors. Their astounding results were recently revealed in the July 2010 issue of Sky & Telescope. American poet Walt Whitman refers to the precession in his poem titled the “Year of Meteors (1859-60.)” in his landmark work Leaves of Grass. This sighting has been popularly mis-attributed to the great Leonid meteor storm of 1833, which Whitman did indeed witness. The shower, however, occurred a full 26 years prior to the mentioned date; also, Whitman, an avid amateur astronomer and sky observer himself, referred to “the strange huge meteor-procession dazzling and clear shooting over our heads,” describing a stately train and not the quick apparition indicative of early morning meteors… just what did Walt see? A major breakthrough came from the art and news reports of the day; several eyewitness accounts describe a sight similar to Whitman’s over the US Northeast on July 20, 1860. Artist Frederic Church also captured a faithful rendition (see above) of just such a meteor procession. Such an event occurs when a large meteor comes in at an oblique angle to our atmosphere, creating a bolide train that can be visible for several minutes. Just such an event was captured on video in modern times over the Teton Range in Wyoming on August 10, 1972. The event can be particularly spectacular if the meteor breaks apart, as apparently happened in 1860. We can also thank Church as a member of the Realist school for depicting the event with such stark authenticity…just think, a few centuries prior, and we would have depicted the bolide with garnishing or a trailing banner! Hats off to Sinnott and the staff and students of Texas State University for an astronomical mystery well sleuthed and solved… just how many other astro-tales are out there in art and literature, waiting to be told?

17.04.10- The Case of the Vanishing Moon: Solved.

(Credit: NASA/ESA/STScI/AURA)

(Credit: NASA/ESA/STScI/AURA)

The scale of the enormous and thin Phoebe Ring as recently imaged by Spitzer.

 

   Since its discovery by Giovanni Cassini in 1671, Saturn’s moon Iapetus has confounded astronomers. Even early on, observers knew something curious was going on with this far off moon; Iapetus varies in brightness between +10 & +12th magnitude as it orbits the ringed planet, nearly vanishing from sight for half its orbit! Late last year, NASA’s Cassini spacecraft and the Spitzer Space Infrared Telescope fingered the culprit; a tenuous outer ring of material now known as the Phoebe Ring that is raining down material on its surface. Like our own Moon, Iapetus is tidally locked in its 79 day orbit. As a consequence, the leading edge plows through this dusty stream of debris. This also causes sunlight to warm and sublimate icy material on the leading side, which streams and re-condenses on the trailing end. This nicely explains the sharply defined and complex boundary seen between the two hemispheres. Alas, no monolith as depicted in Clarke’s original 2001 novel adaptation. .. but perhaps a fine site one day for a cosmic ski resort!

03.04.10- Messenger and the Mysteries of Mercury.

Neutral & Ionized Sodium as seen by the Messenger spacecraft. (Credit: NASA).

Neutral & Ionized Sodium as seen by the Messenger spacecraft. (Credit: NASA).

 

   The history of the inner most planet is an enduring puzzle to planetary scientists. On September 29th of last year, NASA’s Messenger spacecraft passed within 142 miles of Mercury’s night side in an orbital “tweak” on its way to eventual orbital insertion on March 18th, 2011. During that pass, the spacecraft once again measured the trailing exo-sphere, a thin trailing wind made of sodium, potassium, calcium, and magnesium. This “mercurial wind” is replenished either by solar radiation pressure, micro-meteoroid impact, or a combination of the two. The mystery is the ratios of calcium and magnesium observed that is significantly different than predicted. Mercury is a rocky iron world that is over half core and believed to have only a thin mantle and crust. Either Mercury formed that way early in its history, a young Sun boiled away a majority of silicates, or Mercury suffered a major crust stripping impact. Further evidence for the impact scenario comes from Messenger’s neutron spectrometer, which registered a conspicuous lack of low-energy neutrons emanating from the surface of the planet itself. This is highly suggestive of an iron and titanium rich surface similar to what’s found in basaltic rock on the lunar near side. Whatever the case, plenty of surprises await us as Messenger takes up permanent residence around Mercury next year!