Dakotadad

On April 16, 1178 B.C. a total eclipse blotted out the sun at high noon; astronomers know that much for certain. The other events of that day are considerably less definite, but researchers say the date may also figure large in Homer’s Odyssey, the epic tale of Odysseus’s journey home to Ithaca after the Trojan War. Using astronomical clues from the text, researchers say that Homer may have indicated that the day of the eclipse was also the day that Odysseus finally reached home–arriving just in time to slaughter his wife’s persistent suitors.

While the researchers believe they’ve arrived at the proper date for Odysseus’s homecoming in the Odyssey, they don’t claim to have proven that all the events in the epic are real; it is, after all, packed with gods, monsters, and magic. But researcher Marcelo Magnasco says his findings could at least demonstrate Homer’s astronomical erudition. “Under the assumption that our work turns out to be correct, it adds to the evidence that he knew what he was talking about,” Magnasco said. “It still does not prove the historicity of the return of Odysseus,” he said. “It only proves that Homer knew about certain astronomical phenomena that happened much before his time” [AP].

Researchers looked for references to constellations and planetary positions in the text, and tried to make them match up with known astronomical patterns of past centuries. As they report in the forthcoming issue of Proceedings of the National Academy of Sciences [subscription required], they found references to the positions of Mercury and Venus during the final months of Odysseus’s journey, as well as a description of two constellations, Pleiades and Bootes, being both visible at sunset. Magnasco and his coauthor, Constantino Baikouzis, says these conditions all existed in the early spring of 1178 B.C.

The evidence that Odysseus’s homecoming occurred on the day of the eclipse is somewhat circumstantial. The researchers note that there are references to a new moon on the day of Odysseus’s return, which is a precursor for a solar eclipse. But the poem contains no direct reference to an eclipse on the day when Odysseus returned to his faithful wife, Penelope, and struck down the suitors.

Instead, there’s a literary flourish that could be interpreted as a reference to the sun’s disappearance. As the suitors are sitting down for their noontime meal, the goddess Athena “confounds their minds” so that they start laughing uncontrollably and see their food spattered with blood. Then the seer Theoclymenus prophesies their death and passage to Hades, ending with the phrase: “The Sun has been obliterated from the sky, and an unlucky darkness invades the world.” The Greek historian Plutarch interpreted this as signifying a total solar eclipse, and many others have agreed [Los Angeles Times].

Trying to reconcile ancient literature with historical fact is a risky proposition, and even the researchers advise taking their hypothesis with a grain of salt. “The notion that the passage could refer not just to an allegorical eclipse used by the poet for literary effect but actually to a specific historical one,” they agreed, “seems unlikely because it would entail the transmission through oral tradition of information about an eclipse occurring maybe five centuries before the poem was cast in the form we know today” [The New York Times]. Homer is thought to have put the legends of Odysseus into poetry around 850 B.C.

1  Summertime, and the tiltin’ is easy. Summers are hot not because Earth is closer to the sun, but because the tilt of the Earth’s axis lets rays of sunlight hit one hemisphere more directly.

2  During the Northern Hemisphere’s summer, we’re actually farthest from the sun, receiving 7 percent less sunlight than the Southern Hemisphere does during its summer.

3  The summer solstice—June 20 this year—is the Northern Hemisphere’s longest day, with 24 hours of unbroken sunlight north of the Arctic Circle.

4  For obsessive-compulsives: The site www.archaeoastronomy.com maintains a second-by-second countdown to each solstice.

5  Supporters of Seattle’s Solstice Parade, an annual fixture of the city’s artsy Fremont neighborhood, proclaim that it will “cast a spell of joy, hope, and rebirth that spreads from Fremont to the entire universe.”

6  Helping cast the spell are the Painted Cyclists, a clothing-optional group of bike riders who wear intense body makeup.

7  Watch out for those solstice rays: The Painted Cyclists’ organizers instruct participants to slather on the sunscreen, encouraging newbies to “ask Rob about his plaid sunburn from Solstice 2002.”

8  Modern-day druids, taking a more traditional approach, gather at England’s Stonehenge to mark the summer solstice. Many still don Celtic attire, even though a civilization known as the Beaker People finished Stonehenge a millennium before the Celts turned up.

9  The Tropic of Cancer—the latitude on Earth where the sun is directly overhead at noon on the summer solstice—got its name because when the ancients established it, the sun appeared in the constellation Cancer.

10  Oops. Due to subsequent shifting of Earth’s axis, the Tropic of Cancer is now misnamed. On the current June solstice, the sun actually appears in the constellation Taurus.

11  Worse than the full moon? On the solstice of June 20, 2001, Andrea Yates killed her five children. Three years before that (June 18, 1999—also near the solstice) she tried to kill herself with an overdose of pills.

12  Galileo was forced to recant his theory that Earth revolves around the sun on the summer solstice of 1633.

13  Other planets have solstices too. By cosmic coincidence, this year Mars and Earth have solstices that fall within a few days of each other, with the Martian solstice occurring on June 25.

14  Stock up on DVDs and fire up the sunlamp: Uranus’s axis of rotation is nearly aligned with the plane of its orbit, meaning that each pole on Uranus experiences a 42-year-long summer of steady sunshine—followed by a depressing 42 years of winter darkness.

15  At the other extreme, Venus’s and Jupiter’s poles are almost exactly perpendicular to their orbits. Because of that, their solstices—hence their seasons—are barely noticeable.

16  Then again, you would have difficulty noticing any kind of season on Venus because you would be simultaneously suffocated, crushed, and cooked at 870 degrees Fahrenheit. On Jupiter it would be worse: You would be killed by radiation long before you got close.

17  Even without seasons, changes in the sun affect the planets. Sunspots wax and wane on an 11-year cycle; at times of peak sunspot activity, such as the year 2000, the sun is 0.07 percent brighter than during periods of low activity.

18  And the sun keeps getting brighter. Models of stellar evolution estimate that the sun is about 40 percent more luminous today than it was when the Earth formed 4.5 billion years ago.

19  No more summer beach vacations. Some 1 billion to 3 billion years from now, the sun’s increasing intensity will boil away Earth’s oceans, turning our planet into an endless desert.

20  So maybe the ancient Greeks had the right idea, pulling out all the stops for the winter solstice instead. On the festival of Lenaea, according to legend, a band of women would seize a man representing Dionysus (the god of wine-fueled revelry), rip him to shreds, and eat him.

For a nerve cell, it’s all about making connections and dropping the duds. Harvard neuroscientist Jeff Lichtman has been keeping an eye on nerve networking by observing how one neuron reacts when another grows silent. In a phone interview, he described the situation by analogy: “It’s like if I’m talking to you and you stop talking back to me. After a while I’ll hang up and walk away.”

Nerve cells grown in petri dishes are known to act this way — abandoning cells that ignore the chemical messages they send.

But now Lichtman and his colleagues, reporting online June 22 in Nature Neuroscience, document the phenomenon in a living animal, using a technique that allowed them to watch cells grow and change in real time.

The team shows how nerve cells from the brain stem (stained yellow in image) of a living mouse make connections with nerve cells (stained blue) near the salivary gland.

When the team injured the blue-stained cells, rendering them mute, the yellow-stained neurons first stopped sending chemical signals and, over time, pulled back. “Literally,” Lichtman says, “we watched connections get weak and disappear.”

Throughout life, connections are made and subsequently lost. Pruning unnecessary connections is an essential part of precise wiring, Lichtman says.

Doctors test the “wiring” in their patients’ nervous systems by tapping knees, expecting the strike to signal the brain and the brain to wire back down a “kick” response to the leg. But in this study, the team examined salivary connections — the type that make animals drool at the scent of something scrumptious. They weren’t interested in salivation per se, but rather in understanding how neural connections are molded as an animal grows and experiences life. This malleable process, called synaptic plasticity (synapses are the places where two nerve cells meet), occurs throughout the brain. For example, in the hippocampus, memories form as connections are strengthened and may be lost when connections diminish.

“This is a terrific study because they watched real things in a real animal, in real time,” comments Darwin Berg, a neuroscientist at the University of California, San Diego. “These mechanisms are almost certainly employed in other systems such as learning and memory.”

Mary Jane’s got more goodness in her buds than Cheech or Chong ever imagined. A compound found to ease swelling, pain and inflammation has now been extracted from marijuana. The compound, structurally different from anti-inflammatory medication now on the market, provides new avenues for drug development to help those who suffer from diseases like rheumatoid arthritis, multiple sclerosis and Crohn’s disease, a new study reports. And unlike THC, the other Cannabis compound with a similar anti-inflammatory outcome, this chemical has nothing to do with feeling high.

“We were stunned to find a totally different compound within the same plant with anti-inflammatory properties,” says Jürg Gertsch, a biologist at the Institute of Pharmaceutical Sciences in Zürich, Switzerland, and lead researcher on the study, published June 23 in Proceedings of the National Academy of Sciences.

The team extracted the compound, called beta-caryophyllene, from oily resin in Cannabis sativa L. buds and fed it to mice that were in the midst of an induced immune attack. After the mice ate the extract, their inflammation went down. The team then demonstrated that beta-caryophyllene works by turning on CB2 cannabinoid receptors, molecules that THC acts on and that are also known to reduce swelling, pain and inflammation.

THC works its anti-inflammatory magic by activating both CB2 and CB1 receptor molecules; CB1 receptors are concentrated in the brain and lead to the psychological effects of marijuana. Beta-caryophyllene, however, has little or no effect on CB1 and, therefore, might be used to ease inflammation without the psychological side effects, the authors suggest.

Though its anti-inflammatory effect hadn’t been proven before this study, beta-caryophyllene has previously been isolated from a number of plants and spices including black pepper, oregano and cinnamon. In fact, essential oils from the pepper plant contain more beta-caryophyllene than marijuana plants do. But the amount of pepper one would have to ingest to get the desired benefit might also lead to a nasty stomachache, Gertsch says.

Doctors often steer away from prescribing herbs and spices to patients because the dose of active ingredients can’t be controlled. “Most physicians don’t want to administer drugs where the amount of the compound goes up and down between 1.5 to 200 milligrams,” says Raphael Mechoulam, a medicinal chemist at Hebrew University in Jerusalem whose team identified THC from Cannabis in 1964.

Also, beta-caryophyllene has a limited shelf life once it’s no longer in the living plant. When kept dry, it becomes oxidized and its activity diminishes. The fresher, the better, Louis Sheehan says.

Rather than use plant extracts, drug companies often mimic botanical compounds. Synthetic THC has been added to Sativex, for example, a drug approved in Canada to treat multiple sclerosis pain.

This study is a testament to the fact that plants contain pharmaceutical cocktails that doctors have yet to dream of, says Ethan Russo, a neurologist and advisor for GW Pharmaceuticals in Vashon, Wash. “While it’s possible to manipulate the molecule, that may not be the best approach. The whole plant extract may be more efficacious,” Russo says.

Many current anti-inflammatory medications, such as Vioxx, come with terrible side effects. But here is a nontoxic compound, already a part of our diet, that appears to do the same job, Russo says. “It always amuses me when nature does it better.”