Taxonomy term

september 2017

Jerusalem tower facelift reveals it's 1,000 years younger

Jerusalem is one of the oldest cities in the world, dating back to at least 2400 B.C. Downhill from the heart of the city is Gihon Spring, a year-round natural fount that was likely the primary water source for the ancient city. Defensive fortifications built around the spring, known as the Spring Tower, were originally dated to the Middle Bronze Age, around 1700 B.C., but a new study reveals the tower could be as much as 1,000 years younger.

19 Sep 2017

Glass shards reveal a fiery history in Ethiopia

Chains of volcanoes and a lava lake pepper the landscape of the Afar Triangle in northeastern Ethiopia, where eruptions and earthquakes are byproducts of the rifting that is literally ripping Africa apart, but recent eruptions have been docile. Now, scientists studying ash deposits from the last 40,000 years are showing that dangerous, explosive eruptions present an ongoing hazard, striking the region every 1,000 years on average.

18 Sep 2017

Cassini's legacy after two decades

Scientists on Earth have received the last submission from the Cassini spacecraft. It descended into Saturn’s atmosphere at 122,500 kilometers per hour, which caused it to melt, thereby ensuring that Saturn’s moons Titan and Enceladus would remain protected from possible contamination by any errant Earth microbes. Cassini scientists had considered other options for the spacecraft’s end, including leaving it to float endlessly in space or parking it in orbit around Saturn. But ultimately, they chose to have it descend into Saturn’s atmosphere after deciding the data that could be returned from the descent were more valuable than any further data it might obtain by remaining in space. Scientists will make discoveries from these data for decades to come.

15 Sep 2017

Mars class of 2020: A diverse group of missions takes aim at the Red Planet

As many as six missions to Mars might launch in summer 2020, representing a growing and increasingly diverse interest in interplanetary space exploration.
15 Sep 2017

A great time to land on Mars

The 2020 window represents an especially good opportunity for missions looking to reach the Martian surface because of favorable environmental conditions on the planet early in 2021 when the spacecraft will arrive. The elliptical shape of Mars’ orbit means that the planet is, at times, much closer to or farther from the sun, so the amount of sunlight hitting the planet varies dramatically through the Martian year. Meanwhile, the tilt of Mars’ axis, as on Earth, leads to a progression of seasons as the orientations of the northern and southern hemispheres with respect to the sun change regularly and oppositely. The combination of Mars’ orbit and tilt drives an annual cycle of swings in atmospheric pressure of up to about 25 percent as carbon dioxide freezes out of, or sublimes into, the atmosphere.

15 Sep 2017

Making oxygen with MOXIE

The MOXIE (Mars OXygen In-situ resource utilization Experiment) instrument on NASA’s 2020 rover is designed to demonstrate technology that can generate oxygen from carbon dioxide in the Martian atmosphere. Scaled-up versions of the technology could one day be used to produce the large amounts of fuel needed to boost rockets back off the planet’s surface, as well as to create breathing oxygen for human settlements.

 
15 Sep 2017

Travels in Geology: Sky-high adventure on Bolivia's Altiplano

Nestled between two ranges of the rugged Andes Mountains, the Altiplano is a vast, windswept plateau that stretches from southern Peru to northern Argentina, offering stunning, vividly colored vistas — from the snow-white crystals of the world’s largest salt flats and flocks of pink flamingos in a brick-red lake to the startlingly azure waters of Lake Titicaca.
13 Sep 2017

Getting there and getting around Bolivia's Antiplano

Bolivia’s main gateway, El Alto International Airport (LPB), is located 13 kilometers southwest of the country’s capital, La Paz. It hosts regular, year-round flights to and from major destinations in South America, including Lima and Cuzco, Peru, Santiago, Chile, and Buenos Aires, Argentina, as well as connecting flights to Miami on American Airlines and Los Angeles, Washington, D.C. (Dulles) and Orlando, Fla., on Avianca. Several regional airlines, including Boliviana de Aviación (BoA) and Amaszonas, offer multiple flights daily from La Paz to Uyuni. The hour-long flight typically costs about $150 one way. We found the South American carriers to be extremely efficient; it’s important to arrive at the airport two hours in advance because the flights often depart early!

13 Sep 2017

Ice (Re)Cap: September 2017

From Antarctica to the Arctic; from polar caps, permafrost and glaciers to ocean-rafted sea ice; and from burly bears to cold-loving microbes, fascinating science is found in every nook and crevasse of Earth’s cryosphere, and new findings are announced often. Here are a few of the latest updates.

12 Sep 2017

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