Tuesday, December 26, 2017

Louis Pasteur


Louis Pasteur (1822–1895) was a French chemist and microbiologist renowned for his discoveries of the principles of vaccination, microbial fermentation, and pasteurization. He reduced mortality from puerperal fever, and created the first vaccines for rabies and anthrax. His medical discoveries provided direct support for the germ theory of disease and its application in clinical medicine. Together with Ferdinand Cohn and Robert Koch, he is regarded as one of the main founders of bacteriology.

Saturday, December 23, 2017

The oldest astronomical observatory in Asia

Korea-Gyeongju-Cheomseongdae-02

Cheomseongdae is an astronomical observatory in Gyeongju, South Korea. It is the oldest surviving astronomical observatory in Asia. It was constructed in the 7th century in the kingdom of Silla. Cheomseongdae was designated as South Korea's 31st national treasure in 1962. Modeled on Baekje's Jeomseongdae, which now exists only in historical records, Cheomseongdae influenced the construction of a Japanese observatory in 675, and Duke Zhou's observatory in China in 723.

Friday, December 8, 2017

Io: the most volcanic body in the solar system


Io, the most volcanic body in the solar system is seen in the highest resolution obtained to date by NASA's Galileo spacecraft. The smallest features that can be discerned are 2.5 kilometers in size. There are rugged mountains several kilometers high, layered materials forming plateaus, and many irregular depressions called volcanic calderas. Several of the dark, flow-like features correspond to hot spots, and may be active lava flows. There are no landforms resembling impact craters, as the volcanism covers the surface with new deposits much more rapidly than the flux of comets and asteroids can create large impact craters. The picture is centered on the side of Io that always faces away from Jupiter; north is to the top.

Color images acquired on September 7, 1996 have been merged with higher resolution images acquired on November 6, 1996 by the Solid State Imaging (CCD) system aboard NASA's Galileo spacecraft. The color is composed of data taken, at a range of 487,000 kilometers, in the near-infrared, green, and violet filters and has been enhanced to emphasize the extraordinary variations in color and brightness that characterize Io's face. The high resolution images were obtained at ranges which varied from 245,719 kilometers to 403,100 kilometers.

Launched in October 1989, Galileo entered orbit around Jupiter on December 7, 1995. The spacecraft's mission is to conduct detailed studies of the giant planet, its largest moons and the Jovian magnetic environment. The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.
 

Saturday, December 2, 2017

Airglow of the Earth's atmosphere

Panoramic shot of the VLT platform
Airglow over the VLT (Very Large Telescope) platform.

Airglow, a faint emission of light by a planetary atmosphere, is caused by various processes in the upper atmosphere, such as the recombination of atoms which were photoionized by the sun during the day, luminescence caused by cosmic rays striking the upper atmosphere, and chemiluminescence caused mainly by oxygen and nitrogen reacting with hydroxyl ions at heights of a few hundred kilometres. It is not noticeable during the daytime because of the scattered light from the sun. The airglow at night may be bright enough to be noticed by an observer and is generally bluish in colour.
 

Friday, December 1, 2017

Beringian wolfs from the last Ice Age

Beringian wolves diorama

The Beringian wolf lived during the last Ice Age in northern Wyoming, the Yukon and Alaska. The wolf was robust, with strong jaws and teeth. The unique adaptation of the skull and dentition of the Beringian wolf allowed it to produce relatively large bite forces, grapple with large struggling prey, and therefore to predate and scavenge on Pleistocene megafauna. The wolf has been comprehensively studied, yielding new information on the prey species and feeding behavior of prehistoric wolves. The Beringian wolf preyed most often on horse and steppe bison, and also on caribou, mammoth, and woodland musk ox. The species survived well into the Holocene before its extinction at the close of the Ice Age, when cold and dry conditions abated and much of its prey also went extinct. The remains of ancient wolves with similar skulls and dentition have been found in north-east Siberia.

Wednesday, November 29, 2017

Origami swan

2014 Origami moduĊ‚owe
A swan created using modular origami, a paperfolding technique which uses two or more sheets of paper to create a larger and more complex structure than possible with single-piece origami techniques. Each individual sheet of paper is folded into a module, or unit, and then modules are assembled into an integrated flat shape or three-dimensional structure by inserting flaps into pockets created by the folding process. These insertions create tension or friction that holds the model together.

Tuesday, November 28, 2017

Eruption of Mount Agung

Mount Agung, November 2017 eruption - 27 Nov 2017 02

In 2017 Mount Agung, a volcano on the island of Bali in Indonesia erupted violently enough to cause evacuation and air-flight disruption. As of 27 November 2017 the alert level is at its highest and evacuation orders are in place. The eruption caused some 40,000 people to be evacuated from 22 villages around Mount Agung. It also caused surrounding airports to be closed. Lombok International Airport, located on the neighboring island of Lombok, closed on 26 November and was reopened the next morning. Ngurah Rai International Airport, located at the southern tip of the island and southwest of the volcano, closed on 27 November. More than 400 flights were canceled, and about 50,000 passengers were grounded.

Monday, November 27, 2017

Oumuamua: the first interstellar asteroid

Eso1737a-shorter

Oumuamua is the first interstellar object to pass through the Solar System. It was discovered on a highly eccentric hyperbolic trajectory on 19 October 2017, 40 days after turning around the Sun. The first observations were made by the Pan-STARRS telescope when the object was 0.2 AU from Earth, heading away from the Sun. It is the first of a new class of interstellar objects. As a result of its strongly hyperbolic trajectory, it will pass Neptune's orbit in 2022 and leave the Oort cloud in roughly 20,000 years. The amount of time the object has been drifting among the stars in the galactic disc is unknown.




Curiosity rover in search of microbial life on Mars

Curiosity - Robot Geologist and Chemist in One!

This image features NASA's Curiosity rover, a mobile robot for investigating Mars' past or present ability to sustain microbial life. Curiosity landed near the Martian equator on Aug. 5 PDT. In this picture, the rover examines a rock on Mars with a set of tools at the end of the rover's arm, which extends about 7 feet (2 meters). Two instruments on the arm can study rocks up close. A drill can collect sample material from inside of rocks and a scoop can pick up samples of soil. The arm can sieve the samples and deliver fine powder to instruments inside the rover for thorough analysis. The mast, or rover's "head," rises to about 6.9 feet above ground level, about as tall as a basketball player. This mast supports two remote-sensing science instruments: the Mast Camera, or "eyes," for stereo color viewing of surrounding terrain and material collected by the arm; and, the Chemistry and Camera instrument, which uses a laser to vaporize a speck of material on rocks up to about 23 feet away and determines what elements the rocks are made of.