09 agosto 2015
HCG 87: A Small Group of Galaxies
Sometimes galaxies form groups. For example, our own Milky Way Galaxy is part of the Local Group of Galaxies. Small, compact groups, like Hickson Compact Group 87 (HCG 87) shown above, are interesting partly because they slowly self-destruct. Indeed, the galaxies of HCG 87 are gravitationally stretching each other during their 100-million year orbits around a common center. The pulling creates colliding gas that causes bright bursts of star formation and feeds matter into their active galaxy centers. HCG 87 is composed of a large edge-on spiral galaxy visible near the image center, an elliptical galaxy visible to its right, and a spiral galaxy visible near the top. The small spiral near the center might be far in the distance. Several stars from our Galaxy are also visible in the foreground. Studying groups like HCG 87 allows insight into how all galaxies form and evolve.
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solar corona, photographed by soho, 19th may 2015.difference...
solar corona, photographed by soho, 19th may 2015.
difference between successive images; 15 frames in each gif, covering 20 hours.
image credit: nasa/soho. animation: ageofdestruction.
agethis weird-looking knife is, in fact, an elephant sword. This...
this weird-looking knife is, in fact, an elephant sword. This would be attached to war elephants’ tusks! Only four pairs survive today, though elephant swords were used at least since the 600s. This example comes from India circa 1400s to 1600s.
August 9th 1945: Nagasaki bombedOn this day in 1945, the United...
August 9th 1945: Nagasaki bombed
On this day in 1945, the United States dropped an atomic bomb on the Japanese city of Nagasaki, in the second nuclear attack in history. Whilst other Axis powers, including Nazi Germany, had already surrendered earlier that year - thus ending the war in the European theatre - Japan had continued to fight the Allied forces. Throughout the war, the United States had been working on the top-secret Manhattan Project, seeking to harness the destructive power of nuclear energy. The bomb was successfully developed, and nuclear attacks were deemed necessary by the United States government under President Harry Truman, to end the war and avoid a costly land invasion of Japan. On August 6th 1945, the American plane Enola Gay dropped the bomb called ‘Little Boy’ on Hiroshima, which killed around 70,000 people instantly. The effects of the radiation killed thousands more in later years, resulting in a catastrophic death toll of around 140,000 people. Three days later, the second bomb was dropped from the Bockscar plane. The initially planned second target was the city of Kokura, but poor visibility led to the ‘Fat Man’ bomb being dropped on Nagasaki instead, resulting in the loss of around 75,000 lives. In both Hiroshima and Nagasaki, the vast majority of casualties were civilian. In the aftermath of the devastating attacks, Japan surrendered to the Allies on August 15th, ending the war in the Pacific theatre of World War Two. Today, the atomic-bomb scarred cities of Hiroshima and Nagasaki provide a sharp reminder of the horrors of nuclear warfare.
70 years ago today
FREE ON KINDLE TODAY! (9th...
FREE ON KINDLE TODAY! (9th August)
Originally presented by Anne Anastasi as an address of the President of the American Psychological Association in 1957 this child psychology and nature nurture debate classic argues that the question “How?” offers a much more constructive approach to the heredity-environment problem; as opposed to the question “Which one?” or “How much?”
Bonus Material
Heredity, Environment, and The Question “How?” builds upon some of Anne Anastasi’s previously published work. Among the most notable of these earlier publications is A Proposed Reorientation in the Heredity Environment Controversy; which is also presented in full.
An image of a Jewish village girl taken circa 1870 in Persia....
An image of a Jewish village girl taken circa 1870 in Persia. She is elaborately decorated with an abundance of silver jewelry, which must have been somewhat uncommon for simple villagers, indicating her family had a relatively high economic status. The oblong silver pendant hanging from her neck is similar to those seen worn by women throughout the region, often containing talismans (grains of rice, verses from holy books, etc). Hanging from it, as well as from her headdress, are what appear to be coins, another common jewelry feature of the area.
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