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The Milky Way, along the Galactic plane
Seen in Wavelengths from Radio frequency through Gamma rays
- Radio map at 408 Mhz, showing mainly emission due to scattering of free electrons in the interstellar plasma (i.e. hot gas). The large arc is due to a nearby supernova remnant.
- 21 cm radiation map, showing the distribution of neutral Hydrogen gas in the galactic disk, and a few nearby arcs from recent supernovae.
- Distribution of H2, or molecular Hydrogen.This maps the “cold” gas in the Galaxy, from which stars will eventually form. The actual observed molecule is CO, rather than H2, which is very difficult to detect directly. The star forming layer of gas is remarkably thin. Infrared maps at the wavelengths 12, 60 and 100 microns.
- Infrared emission predominately comes from interstellar dust which is “warmed” to a few 10’s of degrees Kelvin by the ambient radiation field of the Galaxy’s stars.
- Near Infrared emission is dominated by cool stars. Since these are typically either old or long-lived stars, this is our best view of the Galaxy with the hot, bright young stars removed. Dust absorption at these wavelengths is very low and we get a clear view all the way to the Galactic center of the disk and bulge.
- Optical image of the Galaxy showing the huge effects that dust absorption has on our view of the central regions of the Galaxy. The emission is dominated by young and old stars and by the effects of dust.
- X-ray image taken by the Rosat satellite. This view, less clear than the others is dominated by supernova remnants (some of the arc-like features) as well as individual sources of X-radiation from close binary stars or black hole candidates.
- Gamma ray view of the Galaxy is dominated by emission from Cosmic Rays (high energy particles) decelerating in the interstellar medium
SOURCE: Chris Flynn’s Galactic Dynamics: Discovering the Milky Way
This is spectacular. Just think for a moment all the things our eyes can’t see. How could we possibly see things for what they are without the help of human ingenuity and technology?
Bone Remodeling in Micro Gravity
Without the pull of Earth’s gravity our bones behave differently in space.
Normally the spongy material that makes up the structure of our inner bones,.(which basically looks like a sponge,.it’s all fractal,..crazy right?) disintegrates and heals properly.
On Earth the process by which our bones are broken down and repaired is generally balanced, in a healthy person.
For some reason not fully understood the balance between the bone breaking down and being repaired is offset. Scientist think perhaps the bones, not having the “mechanical stress” of our Earth gravity makes our bones feel a little more “relaxed”,..and the body’s skeletal structure basically disintegrates, nice.
The same effect also occurs in people with osteoporosis, although in space it’s much faster. We can counter micro gravities effect on our bones by taking more Vitamin D, exercise, and since 2008, using this bad ass looking machine called the AREB, (advanced resistive exercise device).
Space is not only awesome, it’s a learning tool because as we learn to better keep our bones in good health up in space, we’ll use those same techniques to help people on Earth.
Another great look at mitosis.
Image of the Week - May 20, 2013
CIL:42515 - http://www.cellimagelibrary.org/images/42515
Description: Fluorescence micrograph of a human epithelial cell in mitosis, labeled for alpha tubulin (blue), gamma tubulin (green) and DNA (red). The image was taken with a 100x objective and processed with deconvolution. Honorable Mention, 2004 Olympus BioScapes Competition®.
Authors: Joshua Nordberg, Christopher English, and the 2004 Olympus BioScapes Digital Imaging Competition®
Licensing: Attribution, Non-Commercial, No Derivatives: This image is licensed under a Creative Commons Attribution, Non-Commercial, No Derivatives License.
The struggle is real.
Plasma Jets from Radio Galaxy Hercules A
Why does this galaxy emit such spectacular jets? No one is sure, but it is likely related to an active supermassive black hole at its center. The galaxy at the image center, Hercules A, appears to be a relatively normal elliptical galaxy in visible light. When imaged in radio waves, however, tremendous plasma jets over one million light years long appear. Detailed analyses indicate that the central galaxy, also known as 3C 348, is actually over 1,000 times more massive than our Milky Way Galaxy, and the central black hole is nearly 1,000 times more massive than the black hole at our Milky Way’s center. Pictured above is a visible light image obtained by the Earth-orbiting Hubble Space Telescope superposed with a radio image taken by the recently upgraded Very Large Array (VLA) of radio telescopes in New Mexico, USA. The physics that creates the jets remains a topic of research with a likely energy source being infalling matter swirling toward the central black hole.
Image Credit: NASA, ESA, S. Baum & C. O’Dea (RIT), R. Perley and W. Cotton (NRAO/AUI/NSF),
and the Hubble Heritage Team (STScI/AURA)
Melting aluminum with an electromagnet.
First Asteroid With Rings Discovered (like how cool is that?!)
Until now it seemed that only giant planets had the gravity to hold on to the billions of bits of orbiting ice and dust that make up a ring, but in a paper published today in Nature, astronomers report the discovery of two icy rings around a small object named Chariklo that orbits between Saturn and Uranus.
The discovery was made possible by observations at many sites in South America, including ESO's La Silla Observatory. The origin of these rings remains a mystery, but they may be the result of a collision that created a disc of debris.
"This probably will be the biggest discovery of my career," says Felipe Braga-Ribas of the National Observatory in Brazil, who led the team that found the rings, and who received his Ph.D. just last year.
Our Cosmic Address
Avanzados materiales textiles podrían ser la clave para hacer las misiones humanas a Marte una realidad. Los exploradores humanos en Marte podrían jugar un rol importante en la búsqueda de signos de vida pasada o presente en el Planeta Rojo.
¿Qué haría falta para hacer realidad una misión tripulada a Marte? Un equipo de estudiantes de Ingeniería aeroespacial y textil de la Universidad de Carolina del Norte cree que parte de la solución pudiera estar en avanzados materiales textiles. Los estudiantes unieron fuerzas para hacer frente a los desafíos contra los que la industria aeroespacial ha venido luchando por décadas.