2020年3月

一只苍鹭栖息在加利福尼亚索尔顿海的木桩上 A heron perches on a piling at the Salton Sea in California (© Garret Suhrie/Cavan Images)

Heron lies the Salton Sea

Migratory bird species are predictable frequent fliers, taking to the sky to travel along roughly the same route, at the same time, every year. Following sources of food and water along the way, the birds often fly great distances to reach breeding grounds or places to spend the winter. Today, we're looking at an important stopover for migratory birds—California's largest lake, the Salton Sea.

This shallow saline lake was formed when a dam broke in 1905, causing the Colorado River to flow into a 35-mile-long basin with extensive salt deposits. Now it attracts hundreds of species of birds in what is considered one of the most significant concentrations of bird life in the continental United States. Most of these birds are just passing through, migrating along the north-south route called the Pacific Flyway. They gather here, sometimes in the millions, to feed and regain strength before moving on. Some birds, like the heron pictured in today's photo, may stay here for the season, but most of those who visit in the spring will stay for just a few days before continuing their journey to a summer spot farther north.

柬埔寨吴哥窟的日出 Sunrise at Angkor Wat in Cambodia (© Sergio Diaz/Getty Images)

Sunburst at Angkor

Angkor Wat is the most famous Buddhist temple in Angkor—which is saying a lot, since Angkor Archaeological Park is essentially a 154-square-mile collection of historic temples and related holy sites just outside the city of Siem Reap. If you happen to visit Angkor Wat on the spring equinox, get there in time for sunrise. On the equinox, the sun aligns with the top of the main tower at Angkor Wat before climbing farther into the sky to usher in longer days and shorter nights. Of course, if this photo is any indication, every sunrise at Angkor Wat is spectacular.

NASA astronaut works on International Space Station during a spacewalk in 2006 (© NASA)

A stroll above the stratosphere

If this photo from 200-plus miles above Earth dizzies you, imagine how it felt to be Alexei Leonov on March 18, 1965. The Soviet cosmonaut achieved the first-ever extravehicular activity (EVA—but you and I just call it a spacewalk). He spent about 20 minutes outside the orbiting Voskhod 2 capsule. It was the ultimate risk: no one knew just what could happen to a human body in the vacuum of space. Near heatstroke, drenched with sweat, and with his suit dangerously inflating, Leonov barely made it back inside the airlock.

Of course, the art of EVA has been perfected since, and that vertigo-inducing panorama is now the view from the office for those aboard the International Space Station. The spacewalker you see here isn't Leonov but NASA's Robert Curbeam busily replacing a faulty component. On this mission in 2006, Curbeam set a record with four EVAs in one spaceflight, spending over 24 hours outside the vehicle. Since the ISS's first spacewalk in 1998, over 227 EVAs have been performed by a large cast of astronauts—including a milestone excursion in 2019 that employed the first all-female crew.

纽格兰奇墓，爱尔兰博因河谷 Knowth burial mound in Newgrange, Boyne Valley, Ireland for St Patrick's Day (© whatapicture/plainpicture)

It's a good day to be green

For St. Patrick's Day, we're featuring an image of the Knowth passage grave, part of the Boyne valley tombs, about an hour's drive north of Dublin. In addition to Knowth, this UNESCO World Heritage Site is home to the Newgrange and Dowth passage graves, henges, standing stones, and a significant portion of Western Europe's megalithic art. Knowth, the largest passage grave in the complex, is a 40-foot-high mound with a diameter of 220 feet; two east-west passages run under it that lead to separate burial chambers. The structures predate St. Patrick by nearly 4,000 years, and their original purpose is unclear—but on this day dedicated to celebrating all things Irish, they show off the engineering capabilities of the area's ancient population as well as the natural green beauty of the Irish countryside.

克卢恩国家公园里的凯瑟琳湖和沃辛顿山，育空 (© plainpicture/Design Pics/Robert Postma)

缅因州达马里斯科塔地区的佩马基德灯塔 Pemaquid Point Light in Maine's Damariscotta region (© Tom Whitney/Adobe Stock)

Celebrating 200 years of statehood

We're wandering out onto the striated coastal rocks of Maine's Pemaquid Point at sunrise to mark 200 years since Maine joined the Union as the 23rd US state. With roughly 5,000 miles of jagged, rocky coastline, Maine is studded with dozens of lighthouses, and the light at Pemaquid Point is one of the most celebrated—and historic. First, that history: President John Quincy Adams commissioned the lighthouse in 1827, but it needed to be rebuilt in 1835 after the original began falling apart. (Note: Don't use saltwater when mixing your mortar.) Maine residents chose the Pemaquid Point Light for display on their state's coin as part of the US 50 State Quarters Program.

Visitors to the lighthouse are invited to climb the spiral staircase of the 38-foot tower. At the top, they can see the beacon's original Fresnel lens, which is still in use. Gazing out the window offers a superb vantage point of the ridged coastline below. The ancient metamorphic coastal rock is striped with lighter igneous rock, creating banded ledges and lots of scenic drama.

哥本哈根的环形桥，丹麦 The Circle Bridge in Copenhagen, Denmark (© Lingxiao Xie/Getty Images)

A circular celebration

It's Pi Day, the day we celebrate the mathematical constant π. This day was chosen since today's date (March 14) expressed numerically (in US format) matches the number's first digits, 3.14. Pi represents the ratio of a circle's circumference to its diameter. It can be used to compute the area and circumference of a circle, such as the circles that make up this bridge we're looking at here in Copenhagen. (Who said math wasn't useful in the real world?) Many towns, schools, and museums mark the day with festivities based around mathematics and, of course, serving pie. We can't think of a more delicious way to study geometry.

Jerte Valley in bloom

As winter turns to spring in the Jerte Valley, all eyes are on the cherry blossoms. This tiny region in the Province of Cáceres, Spain, has the perfect microclimate for cherry trees, and there are more than 1.5 million of them here in just 23 square miles. The cherry blossoms last just two weeks before the petals rain down, covering the entire valley. About 40 days later, the first cherries are ready to be picked. Locals make wine, beer, and various foods with them. Cherries are also used for spa and beauty treatments, since they have antioxidants and anti-inflammatory properties, in addition to vitamins and ellagic acid.

Fiesta at Siesta

Here we are in mid-March already, the time of year when college-aged revelers invade the world's beaches, like this one on Florida's Siesta Key. Located in Sarasota County off the state's western shore, the island beach is a fixture on lists of America's top beaches, a standout even in a state where soft, welcoming sands compose over half the 1,200-mile coastline.

Using the onset of spring as an excuse to cut loose is nothing new, going back at least to the ancient Greeks and Romans. But spring break as we know it originated in the 1930s, when Fort Lauderdale began welcoming college swim teams for training. In March 1961, over 50,000 young people vacationed in the city. By the '70s, rising prices and increasing consternation of locals began driving the party from Fort Lauderdale to other Florida beaches, and eventually everywhere else. Tourist-vs.-townie tensions still go strong in spring break hotspots, but the party goes even stronger: throughout the spring break season, airlines can expect to serve around 400,000 more passengers each day than usual in the US alone.

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