The Hydrogen Clouds of M33

Gorgeous spiral galaxy M33 seems to have more than its fair share of glowing hydrogen gas. A prominent member of the local group of galaxies, M33 is also known as the Triangulum Galaxy and lies a mere 3 million light-years away. Sprawling along loose spiral arms that wind toward the core, M33’s giant HII regions are some of the largest known stellar nurseries, sites of the formation of short-lived but very massive stars. Intense ultraviolet radiation from the luminous massive stars ionizes the surrounding hydrogen gas and ultimately produces the characteristic red glow. To highlight the HII regions in this telescopic image, broadband data used to produce a color view of the galaxy were combined with narrowband data recorded through a hydrogen-alpha filter, transmitting the light of the strongest hydrogen emission line. Close-ups of cataloged HII regions appear in the sidebar insets. Use the individual reference number to find their location within the Triangulum Galaxy. For example, giant HII region NGC604 is identified in an inset on the right and appears at position number 15. That’s about 4 o’clock from galaxy center in this portrait of M33. via NASA

Wikipedia article of the day for September 30, 2021

Wikipedia article of the day is Killing of Muhammad al-Durrah. Check it out: Article-Link Summary: The killing of Muhammad al-Durrah took place in the Gaza Strip on 30 September 2000, during the widespread protests and riots of the Second Intifada. Jamal al-Durrah and his 12-year-old son Muhammad were filmed by Talal Abu Rahma, a Palestinian television cameraman freelancing for France 2, as the two were caught in crossfire between Israeli and Palestinian forces. The footage shows the pair crouching behind a concrete cylinder, the boy crying and the father waving, then a burst of gunfire and dust, with the boy slumping over. Some of the footage was broadcast in France with a voiceover from Charles Enderlin, who told viewers that the al-Durrahs had been the target of Israeli fire, killing the boy. This interpretation has been questioned by critics and by the Israel Defense Forces, which retracted an initial apology. After an emotional public funeral, Muhammad was hailed throughout the Muslim world as a martyr, with the scene appearing on postage stamps.

Gigantic Jet Lightning from Puerto Rico

Have you ever seen a gigantic jet? They are extremely rare but tremendously powerful. Gigantic jets are a type of lightning discharge documented only this century that occur between some thunderstorms and the Earth’s ionosphere high above them. Pictured above is the middle and top of one such jet caught last week by a lightning and meteor camera from Puerto Rico, USA. The jet traversed perhaps 70 kilometers in just under one second. Gigantic jets are much different from regular cloud-to-cloud and cloud-to-ground lightning. The bottoms of gigantic jets appear similar in appearance to another type cloud-to-above strike called blue jets, while the tops appear similar to upper-atmosphere red sprites. Although the mechanism and trigger that causes gigantic jets is a topic of research, it is clear that the jets reduce charge imbalance between different parts of Earth’s atmosphere. A good way to look for gigantic jets is to watch a powerful but distant thunderstorm from a clear location. via NASA

Wikipedia article of the day for September 29, 2021

Wikipedia article of the day is U-1-class submarine (Austria-Hungary). Check it out: Article-Link Summary: The two submarines of the U-1 class, U-1 and U-2, were built for the Austro-Hungarian Navy. Constructed according to an American design, they were launched in 1909. A diving chamber, wheels for traveling along the seabed, and other experimental features were tested extensively in sea trials. Their gasoline engines were replaced around the start of World War I over safety and efficiency concerns. The boats have been described by naval historians as obsolete by the time they were commissioned in 1911. Both submarines were mobilized briefly during the Balkan Wars, and otherwise served as training boats before 1915. From 1915 to 1918 they conducted reconnaissance cruises out of Trieste and Pola, though neither sank any enemy vessels during the war. Facing defeat in October 1918, the Austro-Hungarian government transferred the bulk of its fleet, including these submarines, to the newly formed State of Slovenes, Croats and Serbs to avoid having to hand its ships over to the Allied Powers.

Night of the Perseids

Have you ever experienced a meteor shower? To help capture the wonder, a video was taken during the peak of the recent Perseid meteor shower above the Indian Astronomical Observatory in Hanle, India, high up in the Himalayan mountains. Night descends as the video begins, with the central plane of our Milky Way Galaxy approaching from the left and Earth-orbiting satellites zipping by overhead. During the night, the flash of meteors that usually takes less than a second is artificially extended. The green glow of most meteors is typically caused by vaporizing nickel. As the video continues, Orion rises and meteors flare above the 2-meter Himalayan Chandra Telescope and the seven barrels of the High Energy Gamma Ray Telescope (Hagar). The 2 minute 30 second movie ends with the Sun rising, preceded by a false dawn of zodiacal light. via NASA

Wikipedia article of the day for September 28, 2021

Wikipedia article of the day is Lettuce. Check it out: Article-Link Summary: Lettuce (Lactuca sativa) is an annual plant of the daisy family, Asteraceae, often grown as a leaf vegetable, and sometimes for its stem or seeds. Often used for salads, lettuce is also seen in other kinds of food, such as soups, sandwiches and wraps. In addition to its use as a leafy green, it has religious and medicinal significance. World production of lettuce and chicory for 2017 was 27 million tonnes, 56 percent of which came from China. Generally grown as a hardy annual, lettuce is easily cultivated, although it requires relatively low temperatures to prevent it from flowering quickly. It can be plagued by numerous nutrient deficiencies, as well as insect and mammal pests, and fungal and bacterial diseases. Lettuce is a rich source of vitamin K and vitamin A, and a moderate source of folate and iron. Contaminated lettuce can be a source of bacterial, viral, and parasitic outbreaks in humans, including E. coli and Salmonella.