Boston moon

I took the picture on the left in August 1996 from the rooftop observatory at Boston University. I got into astrophotography late in my undergraduate studies and thankfully had great teachers in the observatory curator and a fellow student. This photo was taken the old fashioned way, with chemical film that actually had to be developed. I used an old shutter camera mounted on an even older refractor telescope with a 6.5 inch primary lens (see the telescope above). Most photography of the moon requires only a 1/35 second exposure, the same as typical everyday photography. There are some great lunar features captured in this photo that are worth pointing out. The well defined crater at the top right with the central peak is Crater Theophilus, about 60 miles across. The central peak was formed when the lunar crust, punched in by the impactor, "rebounded". Theophilus has taken a bite out of Crater Cyrillus, just to the left. The crater down and to the left of Cyrillus is Catharina, which has two smaller craters inside it. The relatively smooth area to the right of the 3 main craters is Mare Nectaris, a large impact region that filled with magma following a violent impact. The mare regions are some of the youngest regions on the moon (a couple billion years old) and this is why they show fewer craters. Notice Crater Fracastorius just beneath Nectaris that is filled with mare material. The mare poured over the crater rim and filled it in. I could go on for pages describing things in this image, but I'll stop here. Whenever I get a telescope I fully intend to get back into astrophotography, and I particularly look forward to using digital cameras.

summer solstice

Summer solstice 2006 occurred at 12:26 UTC time today, June 21. To an observer at the intersection of the Prime Meridian and the Tropic of Cancer (23.5 degrees north latitude) the sun was directly overhead at 12:26 local time. Every other location along the Tropic of Cancer will find the sun directly over head at their local noon. Regardless, today is the longest day of the year in the Northern Hemisphere. Summer is officially here.

STS-121

The second space shuttle flight since the loss of Columbia is scheduled for July 1. Shuttle missions have been delayed nearly a year to allow for design changes to the shuttle's external fuel tank insulation system. Falling foam debris from the external fuel tank damaged the Columbia orbiter and resulted in the breakup of the vehicle during re-entry in 2003. Following initial design changes, foam debris was still a persistent problem during the first launch of the shuttle since Columbia in July 2005. Additional design changes bring us up to date, with the launch of shuttle Discovery on mission STS-121 July 1. During this mission, the shuttle will dock with the International Space Station and test some of the new safety measures that have been put in place since the Columbia accident. For one, the exterior of the shuttle will be inspected for launch damage using a new laser detection system shortly before re-entry.

From left to right are Michael Fossum, Thomas Reiter, Mark Kelley, Steven Lindsey, Lisa Nowak, Stephanie Wilson, and Piers Sellers.

Hawking on space

The most visible physicist in the world has voiced his opinion on the future of mankind. Stephen Hawking, the British astrophysicist who made a name for himself with theoretical studies of black holes and the nature of space and time, believes that mankind's long term survival will require travel to space and other worlds. As has become somewhat customary in these days of terrorism and global warming, Hawking is concerned about the present state of man on Earth and our future here. He argues that the human race is more and more likely to annihilate itself or be annihilated by natural disasters. As a result, we must strike out into space to ensure our survival. I think Professor Hawking is being a little pessimistic about our future here on Earth, but I am certainly happy to hear one of mankind's intellectual elite casting a vote for furthering space exploration.

the Flammarion woodcut

The above woodcut was commissioned sometime in the 1870s by Camille Flammarion, a French astronomer. The image first appeared in a Flammarion publication in 1888 and through some historical confusion was eventually mistaken as an image of Medieval origin, depicting the flat Earth and heaven. In all likelihood, the intent was to show man's emerging knowledge of celestial mechanics.

Antikythera Mechanism

The following article is not greatly informative, after all we really don't know what the Antikythera Mechanism really did, but it is interesting and reminds us to appreciate the considerable astronomical understanding of ancient peoples.





Ancient Astronomy Artifact Bears Hidden Text

Jennifer Viegas, Discovery News

June 8, 2006— A shoebox-sized bronze device scooped out of a Roman-era shipwreck at the dawn of the 20th century has baffled scientists for years. Now a British researcher has stunningly established it as the world's oldest surviving astronomy computer.

A team of Greek and British scientists probing the secrets of the artifact, known as the Antikythera Mechanism, has managed to decipher ancient Greek inscriptions unseen for over 2,000 years, members of the project say.

"Part of the text on the machine, over 1,000 characters, had already been deciphered, but we have succeeded in doubling this total," said physician Yiannis Bitsakis.

Bitsakis is part of a multi-disciplinary team of researchers from universities in Athens, Salonika and Cardiff, the Athens National Archaeological Museum and the Hewlett-Packard company.

"We have now deciphered 95 percent of the text," he told AFP.

Scooped out of a Roman shipwreck in 1900 by sponge divers near the southern Greek island of Antikythera, and kept at the Athens National Archaeological Museum, the Mechanism contains over 30 bronze wheels and dials, and is covered in astronomical inscriptions.

Probably once operated by crank, it survives in three main pieces and some smaller fragments.

"(The device) could calculate the position of certain stars, at least the Sun and Moon, and perhaps predict astronomical phenomena," said astrophysicist Xenophon Moussas of Athens University.

"It was probably rare, if not unique," he added.

The rarity of the Antikythera Mechanism precluded its removal from the museum, so an eight-ton "body scanner" had to be assembled onsite for the privately-funded project, which used three-dimensional tomography to expose the unseen inscriptions.

The first appraisal of the artifact's purpose was put forward in the 1960s by British science historian Derek Price, but the latest discovery raises more questions.

"It is a puzzle concerning astronomical and mathematical knowledge in antiquity," said Moussas. "The Mechanism could actually rewrite certain chapters in this area."

"The challenge is to place this device into a scientific context, as it comes almost out of nowhere... and flies in the face of established theory that considers the ancient Greeks were lacking in applied technical knowledge," added Bitsakis, also of Athens University.

The researchers are also looking at the broader remains of the Roman ship for clues to the Mechanism's origin.

One theory is that the device was created in an academy founded by the ancient Stoic philosopher Poseidonios on the Greek island of Rhodes.

The writings of first century AD Roman orator and philosopher Cicero, himself a former student of Poseidonios, cite a device with similarities to the Mechanism.

"Like Alexandria, Rhodes was a great centre of astronomy at the time," said Moussas. "The boat where the device was discovered could have been part of a convoy to Rome, bearing treasure looted from the island for the purpose of a triumph parade staged by Julius Caesar."

The new findings are to be discussed at an international congress scheduled to be held in Athens in November.

the next space telescope

Have a look at the James Webb Space Telescope, JWST for short. This is the telescope that is going to replace the Hubble Space Telescope in a few short years. Hubble isn't done yet, and if NASA manages to find enough money for one more shuttle servicing mission before the fleet is retired, Hubble should last us another 3 or 4 years. Of course, that is provided the aging components hold out (Hubble has been orbiting the Earth for 16 years). If component failure doesn't finish Hubble, a decaying orbit eventually will. The Earth's atmosphere slowly drags Hubble into a steadily lower orbit with each passing year. Without shuttle servicing to bump the orbit higher, the telescope will eventually burn up in the atmosphere. The JWST is the next generation space telescope that will carry on where Hubble leaves off. As you might expect, the JWST will be a substantially more advanced telescope than Hubble. JWST will boast a primary mirror about 6 times the size of the mirror on Hubble. The mirror itself is a honeycomb design made of light weight beryllium hexagons as opposed to the single mirror of Hubble. Unlike Hubble, JWST will be looking so deep into space that it is no longer advantageous to work in the visible portion of the electromagnetic spectrum. The light from such vast distances has lost energy such that the photons now reside in the infrared portion of the spectrum. As a result, JWST will be particularly sensitive to infrared wavelengths. The telescope will orbit beyond the moon in a special gravitational "well" formed from the interaction of the sun, moon, and Earth that will allow it to collect images continuously. Finally, JWST will have a sunshade the size of a tennis court that will protect the sensitive detectors from the sun and assist in cooling the detectors as well. You might wonder how a mirror 6 times the size of Hubble and a sunshade the size of a tennis court can possibly be launched from Earth? JWST will effectively construct itself upon reaching orbit, aligning the hexagonal mirror components and unfurling the sunshade. Truly amazing stuff. JWST is currently slated for a 2013 launch. In case you are wondering who James Webb is, he was the second administrator of NASA and in many ways his stewardship ensured the success of the Apollo program.

golf update

On April 14 I posted about the possibility of a Russian cosmonaut on the International Space Station hitting a golf ball during a space walk. I came out against such a stunt because I don't want to see space activities completely undermined for corporate advertising opportunities. The space walk during which the golf ball was to be hit is happening later tonight. However, as I expected, the golf ball stunt has been scratched from the space walk and postponed to a later date. We don't know why, but my guess is that the schedule of actual mission activities has eaten up the entire 6 hours allotted for the space walk. However, we learned this week that NASA was close to approving the golf ball hit from a safety standpoint but perhaps lingering concerns led to the postponement. Regardless, I'm happy to hear that the repair of an oxygen system, the replacement of a camera, and the retrieval of a contamination monitoring system were given higher priority than a golf ball.