The Galaxy Collision Next Door
Two dwarf galaxies may have smashed together in our Local Group, sparking the nearest “starburst”
Giant galaxies such as the Milky Way and its neighbor Andromeda originated long ago after smaller galaxies crashed together and grew larger. Observing this process in action, however, is difficult because it requires detecting collisions between dwarf galaxies near the edge of the observable universe, where we see galaxies as they appeared more than 10 billion years ago. Now astronomers have uncovered evidence of a similar collision much closer to home—a mere 2.6 million light-years from Earth—in a small galaxy named IC 10, allowing them to watch a dwarf–dwarf smashup in detail.
David Nidever, an astronomer at the University of Michigan, calls IC 10 one of the most intriguing galaxies in the heavens. “It’s the only starburst galaxy in our Local Group of galaxies,” he says. A starburst is a galaxy spawning stars at a rapid rate.
IC 10 emits only a few percent as much light as the Milky Way. Unfortunately, astronomers have taken the better part of a century to unravel the nature of this unusual neighbor, because our galaxy tries to block the view. IC 10 lies behind the Milky Way’s dust in the W-shaped northern constellation Cassiopeia.
Heroes & Inspirations: Rosalind Franklin
Rosalind Franklin was a British biophysicist and X-ray crystallographer who made critical contributions to the understanding of the fine molecular structures of DNA, RNA, viruses, coal, and graphite.
Franklin is best known for her work on the X-ray diffraction images of DNA which led to the discovery of the DNA double helix. According to Francis Crick, her data was key to determining the structure to formulate Crick and Watson’s 1953 model regarding the structure of DNA. Franklin’s images of X-ray diffraction confirming the helical structure of DNA were shown to Watson without her approval or knowledge. This image and her accurate interpretation of the data provided valuable insight into the DNA structure, but Franklin’s scientific contributions to the discovery of the double helix are often overlooked. Unpublished drafts of her papers (written just as she was arranging to leave King’s College London) show that she had independently determined the overall B-form of the DNA helix and the location of the phosphate groups on the outside of the structure. Moreover, it was a report of Franklin’s that convinced Crick and Watson that the backbones had to be on the outside, which was crucial since before this both they and Linus Pauling had independently generated non-illuminating models with the chains inside and the bases pointing outwards.
Rosalind Franklin determined the double helix form of DNA, and that the spines needed to be on the outside, Crick & Watson received the Nobel.
Rosalind is one of the 20 Ladies of Science we are featuring in our Heroes & Inspirations Kickstarter.
The above pendant portrait was done by the Whitney Brown.
You can find out more about the project here: http://www.kickstarter.com/projects/576376494/heroes-and-inspirations-our-new-art-jewelry-line
We would love to have your financial support to help teach more folks about these fantastic women. If you can’t kick in with actual money, we truly appreciate Social Media and word of mouth support.
We are now funded and working towards Stretch Goals (Women of History) and Stretch Bonuses (Free Prismatic Spectrum Earrings). Lets keep the momentum going and bring in more wonderful women to the Heroes & inspirations line.
Replica of Neanderthal skull (Homo neanderthalensis), with a modern human skeleton (Homo sapiens) in the background.
Cruciform tattoo behind the right knee of Ötzi, a well-preserved natural mummy of a Chalcolithic European man who lived about 3,300 B.C. There is speculation that the tattoos on Ötzi’s body, placed over areas with age-conditioned or strain-induced degeneration, were related to pain relief treatments similar to acupressure or acupuncture. If so, this is at least 2000 years before their previously known earliest use in China, around 1,000 B.C.
Photographer Chris Arnade has been documenting the faces of addiction in Hunts Point for quite some time, and recently was there with… his telescope. He writes, "I have forgotten how wonderful it can be to show someone the rings of Saturn for the first time. Or the craters in the moon. I had my telescope in my car and Takeesha and Deja had seen neither. Sometimes people are disappointed, growing up seeing images from the space telescope. Not these two. They loved it. We got the oddest looks."
He told us this morning that "Takeesha was particularly excited, especially about the rings of saturn. Honestly was not much different from anybody else who I have shown who is smart and curious. I found the reaction of the johns more interesting. They would slow down and just stare out their cars. Takeesha would shout at them, 'Hey, you want your dick sucked or you want to look at Saturn?' She has a great sense of humor that way.”
Arnade also noted that he used to be an “astronomy nut,” with a small telescope guiding him through the sky from a cow pasture… “what an odd journey to end up in Hunts Point with a much larger telescope.” He’ll now be setting it up there “about twice a month, to show the neighborhood kids, adults, etc.”
This is kind of how I feel when I’m showing people stuff through my telescope and just informing people about what they’re seeing and how that object got to where it’s at now. One thing that didn’t sit right with me about this article though was the comment "Honestly was not much different from anybody else who I have shown who is smart and curious." As if the photographer was expecting something else. Either way this is a great way of going out into the community and using knowledge for good, I love how it acted as a bonding tool for people of completely different socioeconomic statuses.
"One of the Pleistocene mammals depicted without fail in popular books – encyclopedias of prehistoric life and the like – is the Woolly rhinoceros Coelodonta antiquitatis (the species name is written antiquus in many sources). Originally named in 1807 (but known for some time prior), this cold-adapted, shaggy-coated rhinocerotid rhino occurred from the Atlantic fringes of Europe all the way east to Beringia, and as far south as the southern Caucasus and south-east China. Why it never moved into North America is unknown – it should have.
As is the case for various ‘Ice Age’ megamammals, the Woolly rhino wasn’t necessarily an inhabitant of freezing cold places with blizzards and thick snow on the ground, or even of tundra-dominated habitats. Spanish specimens come from dry, temperate habitats dominated by grasses and broadleaved trees. Fossils of other Coelodonta species show that this group originated in the Tibetan region during the Pliocene, their evolution perhaps driven by the uplift of the Qinghai-Tibet Plateau (Deng 2002, Deng et al. 2011). C. thibetana from Tibet is currently the oldest known member of the group. Previously, the oldest Coelodonta species was the animal usually called C. nihowanensis. It’s been argued that this name is not available as it’s a nomen nudum (a name lacking a type specimen). A Middle Pleistocene rhino, C. tologoijensis, is known from Transbaikalia, Mongolia and perhaps south-western Siberia. These older species are smaller than C. antiquitatis and have more slender limb bones (Kahlke & Lacombat 2008). [Image below by Atirador.]
Plant fragments stuck in Woolly rhino teeth (most typically inside the infundibula – the crescent-shaped recesses present in the middles of the molars) show that they were grazers, 96% or so of their diet being made up of grasses, with mosses and forbs forming the remainder (Guthrie 1990). However, preserved stomach contents show that Woolly rhinos also ate dwarf willows and birches.
The form of the Woolly rhino’s skull and teeth are in agreement with this grazing lifestyle: the mouth and lips are broad, and the head dipped downwards towards the ground, even when the animal was in its normal, relaxed posture. The skull is unusual in having both an extensively ossified nasal septum, and a down-turned anterior region on the premaxilla that contacts the edge of the upper jaw. As a consequence, it has ‘reverted’ to the possession of enclosed bony nostrils – a condition present in mammal ancestors but not, ordinarily, in mammals themselves. The snout region is also unusual in that incisors are wholly absent in both the upper and lower jaws. This is presumably an extreme specialisation for grazing and raises the question as to whether Coelodonta had keratinous pads, or some other, similar structures, in these parts of the jaws” (read more).
(Source: Scientific American)
Mystery of Supermassive Black Holes in the Early Universe —“Not Enough Time for Them to Exist”
An enduring mystery is the existence of supermassive black holes in the early universe—such black holes would have formed less than one billion years after the Big Bang. In previous models, “there was simply not enough time for any black hole to reach a supermassive scale so soon after the birth of the universe,” says Christian Reisswig, NASA Einstein Postdoctoral Fellow in Astrophysics at Caltech and the lead author of the study. “The growth of black holes to supermassive scales in the young universe seems only possible if the ‘seed’ mass of the collapsing object was already sufficiently large.”
Certain models of supermassive black hole growth invoke the presence of “seed” black holes that result from the deaths of very early stars. These seed black holes gain mass and increase in size by picking up the materials around them—a process called accretion—or by merging with other black holes.
Giant Moon-Forming Impact On Early Earth May Have Spawned Magma Ocean
Billions of years ago, the Earth’s atmosphere an opaque and the planet’s surface was a vast magma ocean devoid of life.
This scenario, says Stanford University professor of geophysics Norman Sleep, was what the early Earth looked like just after a cataclysmic impact by a planet-size object that smashed into the infant Earth 4.5 billion years ago andformed the moon. The moon, once fully formed, which would have appeared much larger in the sky at the time, since it was closer to Earth
Stars born in filaments tend to outweigh stars formed in the field
The mass distribution of stars is called the initial mass function, or IMF for short, and it characterizes the properties not only of our Milky Way, but of all the other galaxies we observe as well. But is the IMF constant? Does it vary from galaxy to galaxy? Does it vary within our galaxy? After decades of studying we still are not sure how the environment affects the process of star formation, aside from the fact that the IMF seems peculiarly constant within the Milky Way.
Ironically this failure in our understanding is mainly due to the fact that stars are very private individuals that hide their forming years behind very cold and dusty environments, which we can only probe using long wavelength observations such as those in the infrared. The Herschel mission, however, has recently opened for us a window in the star formation environments with spectacular results.
In Search of Planetary Intelligence
We don’t have it on Earth. But maybe it’s somewhere out there.
It is said that Mahatma Gandhi, when asked about Western civilization, remarked, “I think it would be a good idea.” That’s how I feel about intelligent life on Earth, especially when I think about the question of what truly intelligent life might look like elsewhere in the universe.
What do we mean by intelligence? Like life, it’s hard to define, but we need to if we want to search for it. Among the radio astronomers of SETI—the Search for Extraterrestrial Intelligence—it’s only sort-of a joke that the true hallmark of intelligent life is the creation of radio astronomy.