earth

2012年9月17日星期一

September 2012 guide to the five visible planets

You can easily find four planets in September 2012. You’ll still find two in the evening sky –Mars and Saturn – if you look soon enough after sunset. The two much brighter planets –Venus and Jupiter – are very bright and prominent in the sky before dawn.

The evening planets, Mars and Saturn, are slowly sinking into the glare of evening twilight, so it’ll take a deliberate effort to spot them after sunset this month, especially from northerly latitudes. You’ll need eagle eyes and possibly binoculars to catch the moon with Saturn onSeptember 18 and with Mars on September 19.

As for the morning planets in September 2012, you’ll have no trouble seeing Venus andJupiter – the sky’s brightest and second-brightest planets, respectively. Venus continues to dazzle us in the eastern predawn darkness and morning twilight. From mid-northern latitudes, Venus will rise around 2 a.m. (3 a.m. local daylight saving time) in early September and only about one-half hour later by the month’s end. Jupiter will rise around 11 p.m. local time (12 midnight local daylight saving time) in early September and by about 9 p.m. local time (10 p.m. local daylight saving time) by the end of the month. Jupiter and Venus rise later at more southerly latitudes, so check out the links on our almanac page for the precise rising times in your part of the world.

Jupiter (left) with several of its moons near Earth’s moon (right) on the morning of September 8, 2012. Photo by EarthSky Facebook friend VegaStar Carpentier in Paris. Click here to expand this image.

More on the morning planets: Jupiter and Venus

Venus and Jupiter rise well before the sun in the morning sky all through September. People around the world have been watching these worlds and marveling at their brightness in the morning sky ever since late June and early July 2012. If you haven’t seen them yet, you are really missing out on a fine morning attraction. Venus reached greatest brilliancy around mid-July 2012, but it is still very bright – always the brightest object in Earth’s sky besides the sun and moon. And Jupiter will be brightening – and rising earlier each night – throughout September. Before long, Jupiter will have shifted over into the evening sky. By early December, when Earth will pass between Jupiter and the sun, this bold planet will shine in our sky all night long.

Whereas Jupiter shines in front of the constellation Taurus all through September 2012, Venus starts out in the constellation Gemini the Twins. These two planets quickly part company in the September morning sky. Jupiter stays rather close to the bright starAldebaran throughout the month, but Venus starts out September near the Gemini starsCastor and Pollux and ends the month near Regulus, the brightest star of the constellation Leo.

Here is Venus (upper right) and the very old moon on the morning of September 14, 2012, as seen by EarthSky Facebook friend VegaStar Carpentier in Paris. The moon put on a fine show from about September 7 to September 14, passing the bright stars and planets Venus and Jupiter in the predawn sky. After mid-September, the moon will return to the evening sky. Click here to expand this image.

Jupiter and its moons as seen on August 15, 2009

In other words, Venus passes all the way through the constellation Cancer the Crabin September 2012. You may want to set your alarm clock to see the waning crescent moon pairing up with Venus and Cancer’s Beehive star cluster before dawn on Wednesday, September 12. Look for another fine showing of the moon and Venus (and the star Regulus) before dawnSeptember 13.

September 2012 should be great for telescopic observations of Jupiter. With only a modest backyard telescope, you can easily see Jupiter’s four major moons – Io, Europa, Ganymede and Callisto.

Extremely rare white killer whale caught on camera

Earlier this month (April, 2012) scientists reported the siting of an all-white orca – or killer whale – off the coast of Russia’s Kamchatka Peninsula.

Is this whale – nicknamed Iceberg – the only all-white killer whale on Earth?

Might be. But scientists are wondering whether Iceberg is the same animal as the one photographed by scientists in Alaska’s Aleutian Islands in 2000 and 2008.

Credit: E. Lazareva / Far East Russia Orca Project (FEROP)

Whale biologist Erich Hoyt is co-director of the Far East Russia Orca Project. He described the whale siting:

It was startling to see this 2-meter-high white dorsal fin shooting up among the other killer whales.

The distance between the Aleutians and Russia is nothing for whales that most likely travel between the North Pacific and Hawaii, Hoyt said. And Iceberg, like the Alaska whale, clearly is an adult traveling in a pod of about a dozen animals.

But when Iceberg’s images were compared with the images of the Alaskan whale, Hoyt said:

The easy clues just aren’t there. There is some evidence that they are the same, but other things aren’t quite right. When you look at the pictures side by side, superficially, they don’t look alike, but they were taken under radically different circumstances and many years apart.

Iceberg has been making news all week long and is clearly an internet sensation. Below you can see him swimming with another male orca, believed to be his brother.

Credit: E. Lazareva / Far East Russia Orca Project (FEROP)

It is unclear whether Iceberg is albino, or if he is just somehow genetically different from the rest of his pod. Hoyt and the rest of his researchers have plans to return to the Russian waters in hopes of finding this amazing creature again and gaining more insight into his white-pigmented skin.

Bottom line: In April, 2012, scientists reported the siting of an all-white orca – or killer whale – off the coast of Russia’s Kamchatka Peninsula. They are unsure whether the animal – nicknamed Iceberg – is the same all-white orca as the one photographed by scientists in Alaska’s Aleutian Islands in 2000 and 2008.

from http://earthsky.org/earth/extremely-rare-white-killer-whale-caught-on-camera

Most amazing high def image of Earth so far

This week (January 25, 2012), NASA released what it said is the “most amazing high definition image of Earth” ever. It’s part of NASA’s Blue Marble series. It’s composite image that uses a number of swaths of the Earth’s surface taken on January 4, 2012.

Most recent Blue Marble image, a composite made from multiple images acquired on January 4, 2012. Credit: NASA/NOAA/GSFC/Suomi NPP/VIIRS/Norman Kuring

Click here to expand image above

This image was assembled from images taken from NASA’s most recently launched Earth-observing satellite — Suomi NPP – which was officially named on January 24, 2012 for the late Verner E. Suomi, a meteorologist at the University of Wisconsin who is said to be “the father of satellite meteorology.”

Suomi NPP is NASA’s next Earth-observing research satellite. NASA says it is the first of a new generation of satellites that will observe many facets of our changing Earth.

Moon still between Venus and Jupiter on January 28

Updated images of Eagle Nebula, aka Pillars of Creation

Original Blue Marble image, taken by Apollo 17 astronauts in 1972. This image changed the way people in 1972 thought about the world. Image Credit: NASA

Click here to expand image above

For contrast, here is the original Apollo 17 Blue Marble image, taken by astronauts on their way to the moon. Here’s the original caption:

View of the Earth as seen by the Apollo 17 crew traveling toward the moon. This translunar coast photograph extends from the Mediterranean Sea area to the Antarctica south polar ice cap. This is the first time the Apollo trajectory made it possible to photograph the south polar ice cap. Note the heavy cloud cover in the Southern Hemisphere. Almost the entire coastline of Africa is clearly visible. The Arabian Peninsula can be seen at the northeastern edge of Africa. The large island off the coast of Africa is Madagascar. The Asian mainland is on the horizon toward the northeast.

The Apollo astronauts had the sun behind them when they took the image, so they are seeing all of Earth’s day side – a fully illuminated Earth – much as we sometimes see a full moon in our sky. To the astronauts, Earth had the appearance of a glass marble, hence the name.

Since 1972, NASA has produced a whole series of Blue Marble images. You can see and learn about them here.

Bottom line: On January 25, 2012, NASA released what it said is the “most amazing high definition image of Earth” ever. It’s part of NASA’s Blue Marble series. It’s composite image that uses a number of swaths of the Earth’s surface taken on January 4, 2012. The original Blue Marble image, taken by Apollo 17 astronauts on their way to the moon in 1972, is possibly one of the most viewed images in the world.

Research in Africa reveals new species of monkey

Scientists working in central Africa yesterday announced a new species of monkey. This discovery – in an unexplored forest area in the Democratic Republic of Congo – is only the second time a new monkey species has been found in Africa in the last 28 years. The creature had been known to the locals simply as lesula. It’s a medium-sized, slender animal that looks similar to the owl-faced monkey (Cercopithecus hamlyni) already known to scientists. But the animal’s bottom is colored differently than other owl-faced monkeys. It’s colored blue. Publishing in the journal PLoS One on September 12, 2012, scientists have identified it as a separate species and named it Lesula Cercopithecus lomamiensis. The scientists commented:

We recommend the common name, lesula, for this new species, as it is the vernacular name used over most of its known range.

A new species of monkey found in the Democratic Republic of Congo and identified as Lesula (Cercopithecus lomamiensis). This is a captive adult male. Photo courtesy of Hart et al.

The newly identified monkey – shy lesula – is said to live on leafstalks, fruit and flower buds. The researchers described how they studied the monkey:

Seven specimens of C. lomamiensis and eight specimens of C. hamlyni were used for analyses … Specimens collected in the field included freshly killed animals acquired from local hunters, animals killed by predators (including kills by leopards, Panthera pardus, or crowned eagles, Stephanoaetus coronatus) and one skin snip from a monkey captured locally and kept as a captive in a village near the species’ range.

We used GPS to record locations where specimens were recovered in the field; when exact location of specimen origin was not possible (e.g., location based on hunter reporting), locations were estimated to the nearest settlement or geographic feature.

We took information on the provenance, history and care of all captive animals seen. We took photographs of all specimens and captives, and recorded standard field measurements (total length, tail length, length of hind foot, length of ear pinnae, and body mass) wherever possible.

The young animal looked like an owl faced monkey (Cercopithecus hamlyni) from the front. But its bottom was colored blue – unlike any other known species. Image Credit: PLOS ONE/ J. A. Hart

The new species of monkey came to light after a monkey, known locally as lesula, was found in the forests of the middle Lomami Basin in central Democratic Republic of Congo (DRC) in 2007. A local school director captured the monkey, and, once in captivity, the monkey came to the notice of scientists. They found it had not been previously described in the scientific literature.

The researchers warn the monkey is vulnerable to extinction as a result of hunting for bush meat. They called for controls on hunting and the creation of a protected area covering its range to conserve the lesula and other wildlife found in the region.

Bottom line: For the second time in 28 years, scientists have discovered a new species of monkey in Africa. It looks like an owl-faced monkey already known to science, but it has a blue bottom. The new species is being called Lesula Cercopithecus lomamiensis.

from http://earthsky.org/earth/researchers-find-new-species-of-monkey

Large coral loss seen over some Caribbean reefs

On September 7, 2012 the International Union for Conservation of Nature (IUCN) released a report that tracks the deterioration of coral reefs in the Caribbean over the past 39 years. The report indicates that live coral cover over some reefs in Jamaica, Puerto Rico, the Florida Keys and the US Virgin Islands has dropped to less than 10%. These losses are thought to be driven by a combination of factors including hurricanes, disease, overfishing, pollution and climate change.

In early May 2012, 36 scientists from 18 different countries gathered at the Smithsonian’s Tropical Research Institute in the Republic of Panama to begin the enormous task of assessing coral reef conditions around the world as part of a program called the Global Coral Reef Monitoring Network. The program, administered by the IUCN, is planning to release a global synthesis report of their findings in 2016.

Corals in Belize. Image Credit: Jean-Marc Kuffer via Flickr.

On September 7, 2012 the IUCN released a preliminary report describing the conditions of coral reefs in seven different countries located in the Caribbean.

The new report (pdf) found that total live coral cover from all of the countries examined declined from a high of approximately 58% in 1973 to a low of approximately 8% in 2012.

Among the countries, coral reefs in Bonaire, Curacao and the Cayman Islands showed the least amount of loss, and live coral cover currently ranges from about 20 to 28% in these areas. Reefs in Jamaica, Puerto Rico, the Florida Keys and the US Virgin Islands were found to be the worst off with live coral cover currently ranging from as little as 8 to 10%.

Elkhorn coral with white band disease. Image Credit: Andy Bruckner, NOAA.

Species of Staghorn and Elkhorn corals in Caribbean have been particularly hard hit by white band disease, the report notes. White band disease is a disease in corals whereby live coral tissue dies off leaving behind a discolored band that consists of the corals’ white calcium carbonate skeleton.

Jeremy Jackson, Science Director of the Global Coral Reef Monitoring Network, and his co-authors of the report commented that:

Caribbean reefs with the highest surviving coral cover and least macroalgae tend to be characterized by little land-based pollution, some degree of fisheries regulations and enforcement, moderate economic prosperity, and lower frequency of hurricanes, coral bleaching, and disease. Unraveling the potential interactive role of these and other factors is a major goal of our study once all the necessary data are available.

The full synthesis report containing information about coral reef conditions throughout the Caribbean is expected to be published and available online by March 2013.

Clearly, the amount of live coral cover on Earth will be an important metric to consider in the years ahead.

Bottom line: On September 7, 2012 the International Union for Conservation of Nature (IUCN) released a preliminary report that found that live coral cover over some reefs in Jamaica, Puerto Rico, the Florida Keys and the US Virgin Islands has dropped to less than 10%. The losses are thought to be driven by a combination of factors including hurricanes, disease, overfishing, pollution and climate change. A full synthesis report containing information about coral reef conditions throughout the Caribbean is expected to be published and available online by March 2013.

form http://earthsky.org/earth/large-coral-loss-seen-over-some-caribbean-reefs

Your brain on sugar

Wait! Before you eat that ice cream …. Image Credit: digitalbob8

Did you know that binging on soda and sweets – for as little as six weeks – might do damage to your memory?

A new study suggests that a diet high in fructose – that is, sugars commonly derived from sugar cane, beets and corn – can slows your brain, hampering your memory and learning. Fortunately, this same study also suggests that eating foods that contain nutrients called omega-3 fatty acids – like walnuts, salmon, flax seeds and sardines – can counteract these negative effects.

The study, headed by neuroscientist Fernando Gomez-Pinilla at the University of California Los Angeles, focused on high-fructose corn syrup, an inexpensive liquid that’s six times sweeter than cane sugar. It’s used in many processed foods, including soft drinks, condiments, apple sauce and baby food. According to the U.S. Department of Agriculture, the average American consumes more than 40 pounds of high-fructose corn syrup every year.

The study monitored two groups of rats. Each were fed regular food and trained on a maze twice daily for five days. They were then switched to a diet high in fructose for six weeks.

One group also received omega-3 fatty acids, which protect against damage to synapses — the chemical connections between brain cells that enable memory and learning.

After six weeks on their experimental diet, the rats were tested on the mazes again.

Of the two groups, the rats that received fructose without a supplement of omega-3 fatty acids were slower at completing the maze, and their brain cells had trouble signaling each other, disrupting the rats’ ability to think clearly and recall the maze route.

So what does this mean for us humans? In short, what you eat might have a big impact on how your brain functions.

Listen to the 90-second EarthSky podcast on how eating sugar can damage your memory, at the top of the page