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Infographic: State of the Solar System 2014  [published 28 Mar 2014]
Where we are and where we are going in 2014 … and beyond.
Larger image

Solar System exploration is making spectacular progress. As of early 2014, we have emerged for the first time from the enormous bubble of magnetism and ionized gas that the Sun emits and entered interstellar space. We have had close encounters with all of the planets out to Neptune and we’re on our way to Pluto. We are exploring Mars with two rovers and several orbiters. We are using a fleet of spacecraft for coordinated study of the Sun and its effects on the Solar System. We are in orbit around Mercury, flying to a dwarf planet in the asteroid belt, and continuing an extensive tour of Saturn and its moons. And our exploration out there helps to unite us here on Earth, as many missions are cooperative endeavors with the space agencies of other nations. 

Full Transcript (PDF, 92 KB)

Credit: NASA
SOURCE: NASA: Solar System Exploration

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HOW INFORMATION TRAVELS IN A CELL AND BETWEEN CELLS
Scientific Illustration by Nicole Rager Fuller / Sayo Studios, 2014

  1. The key components of genetics: chromosomes, DNA, RNA, and protein production.
  2. Cell Signaling and Drug Action
  3. Growth factors (the blue and purple spheres) bind to certain receiving proteins, called receptors, which relay the growth factor signals into the cell. These signals are further relayed through a large network of proteins by kinases, which eventually change the activity of genes within the nucleus.
  4. Cell signaling is the process used by cells to communicate with other cells. Signals (hormones, growth factors, calcium, nitric oxide, etc.) originate in a cell, leave, and then enter and are interpreted by another cell.
  5. The protein production process in an animal cell, from transcription and translation, to the folding of amino acids into functional proteins.

(via DNA and Genetics)

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Found! First Earth-Size Planet That Could Potentially Support Life
Astronomers have discovered a planet about the size of Earth,
orbiting its star in the zone where oceans of liquid water would be possible.

From Space.com

A study of the newly-found planet indicates it could have an Earth-like atmosphere and water at its surface. The planet Kepler-186f is the fifth planet of the star Kepler-186, 490 light-years away.

The planet has 1.11 times the Earth’s mass. Its radius is 1.1 times that of Earth. Kepler-186f orbits at 32.5 million miles (52.4 million kilometers) from its parent star. Its year is 130 Earth days. 

The planet orbits Kepler-186, an M-type dwarf star less than half as massive as the sun. Because the star is cooler than the sun, the planet receives solar energy less intense than that received by Mars in our solar system, despite the fact that Kepler-186f orbits much closer to its star.

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Icy Enceladus hides a watery ocean
Alexandra Witze, Nature News & Comment 03 April 2014

A body of water as wide as Lake Superior and as deep as the Mariana Trench bolsters search for life on Saturn moon. 

Planetary scientists have found an ocean buried beneath the south pole of the Saturnian moon Enceladus by studying tiny anomalies in the flybys of the Cassini spacecraft. The discovery, which helps to explain earlier observations of geysers, makes Enceladus only the fourth Solar System body found to have a water ocean — making it a potential cradle for life.

Continue reading in Nature News & Comment …

IMAGES:  [1] The water vapour photographed multiple times by NASA’s Cassini probably originated in a vast underground ocean.  NASA/JPL-Caltech and Space Science Institute ||| [2] A reconstruction of the interior of Enceladus showing an ice outer shell, a relatively low-density rocky core, and a southern-hemisphere water ocean in between.  NASA/JPL-Caltech ||| [3] The lopsided strength of Enceladus’s gravitational field, estimated using the acceleration of the Cassini probe (measured here in milligals, or thousandths of a centimetre per second squared). From Iess et al. 2014, Science/AAAS

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THE SECRET LIFE OF JELLYFISH

Jellyfish, most of the time, look nothing like jellyfish. They look like tiny little bread-crumb sized sea anemones.

These “polyps”, as they’re technically (tragically?) called, can hide all over the place; under shells, docks, logs, etc.

They’re also really good at copying themselves. One polyp can turn into hundreds over a season by growing and dividing. The best part? Like little living 3D printers, they can churn out copies of their same old polyp body over and over again … or they can mix things up and start making a different body: Jellyfish.

Jellyfish as we know them start their lives as little jelly rolls (see what I just did there?) on the polyp body. Each jelly roll develops into a wee jellyfish, which eventually breaks off and swims into the ocean, starting the whole cycle over.

Continue reading at Deep Sea News …
_________________________________________

Based on research reported in Current Biology, Volume 24, Issue 3, 263-273, 16 January 2014: Björn Fuchs, et al.  Regulation of Polyp-to-Jellyfish Transition in Aurelia aurita

The first analysis of life-cycle regulation in a basal metazoan
The life cycle of scyphozoan cnidarians alternates between sessile asexual polyps and pelagic medusa. Transition from one life form to another is triggered by environmental signals, but the molecular cascades involved in the drastic morphological and physiological changes remain unknown.

Our findings uncover the molecule framework controlling the polyp-to-jellyfish transition in a basal metazoan and provide insights into the evolution of complex life cycles in the animal kingdom.

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Baby Squid Photography by Jeannot Kuenzel - Malta
All rights reserved by Jeannot Kuenzel
sharing enabled / downloading enabled
Posted on Flickr March 29 and 31, 2014

top image
EGGS of Loligo vulgaris: the European squid, a large squid belonging to the family Loliginidae.

bottom image

Two stages of the development of a [European squid] are visible in the picture. These eggs are about 3mm in diameter; when the little squid inside has used up all the nutrients (all the yolk that is attached to it), it plops its suckers to the inside of the diaphragm and releases enzymes that will aid opening the shell, pushing through the opening - and a tiny new ALIEN of the DEEP is born :]

Notice the CHROMATOPHORES already embedded in its skin and the tiny little SIPHON… BTW, the SQUID on the left is actually laying on its back…

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THE MINERALOGY OF PROTO-PLANET ‘4 VESTA’
[Modified from an article at Discovery News - via astrovisual]

NASA’s Dawn spacecraft orbited the massive asteroid Vesta in 2011 and 2012, sending back data on landscape, craters and mineral composition.

Using data from the mission, scientists at Max Planck Institute for Solar System Research in Katlenburg-Lindau, Germany have produced a [false-color] view of this otherwise bland landscape.

  • Dawn’s camera system is equipped with seven filters, each filter sensitive to a specific wavelength of light.
  • Normally, Vesta would look gray to the naked eye,
  • but when analyzing the ratios of light through Vesta’s filters,
    the landscape pops with color,
  • each shade representing different kinds of minerals.
  • (Different minerals reflect and absorb different wavelengths of light,)

[1] A “global” model of Vesta shows the abundance of hydrogen on Vesta’s surface … likely from hydroxyl or water bound to minerals in the surface.

  • It is because of its non-ellipsoid shape that Vesta is not labelled a ’dwarf planet’ like Ceres.

[2] The flow of material inside and outside a crater called Aelia is demonstrated. Each color represents a different kind of mineral.

[3] Antonia, a crater located inside the huge Rheasilvia basin in the southern hemisphere of Vesta. 

[4] The impact crater Sextilia can be seen in the lower right of this image. The mottled dark patches are likely impact ejecta from a massive impact and the reddish regions are thought to be rock that melted during the impact. The diversity of the mineralogy is obvious here.

[5] This is the distinctive Oppia crater, an impact that occurred on a slope. This produced an asymmetric ejecta distribution around the crater – the red/orange ejecta material is more abundant around the downward slope than around the upward portion.

ALL IMAGES: NASA/JPL-CALTECH/UCLAMPS/DLR/IDA
SOURCE for images and text: Discovery News

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PHOTOACTIVATION LOCALIZATION MICROSCOPY
Photomicrography by Harald Hess, Janelia Farms Research Institute, HHMI
Images and text reprinted here in abbreviated form.

Three images illustrating the limitation of traditional light microscopy and the power of a super-resolution technique called Photoactivation Localization Microscopy.

  • When a microscope lens collects light from a molecule and reimages it onto a camera, the light forms a “blurry” spot that reflects the size of the light’s wavelength instead of the molecule’s size.
  • This is called “diffraction,” and it restricts the resolution of light microscopy to ~½ the light’s wavelength (~250 nm) or approximately the size of a small mitochondrion.
  • Thus, imaging with traditional light microscopy is like painting with a “blurry” brush. Individual molecules closer in space than ~250 nm will appear as one.

[1] Here a U2OS [human osteosarcoma] cell is labeled with fluorescent proteins and imaged with traditional microscopy using TIRF (total internal reflection) microscopy, with a resolution of ~250 nanometers.

[2] The same cell is now imaged with Photoactivation Localization Microscopyshrinking the resolution from ~250 nm to 20 nm. Individual molecules of the membrane protein farnesyl labeled with a photoactivable fluorescent protein are distinguishable.  

[3] The same cell is rendered using a high-speed version of the super-resolution technique.  This allows real-time imaging in live cells.  3D images can be created by finding the axial position of each molecule with methods such as interferometry.

SOURCE: Zeiss Cell Picture Show

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The Mimic Octopus
MarineBio.org viabiovisual

Taxonomy:  Animalia > Mollusca > Cephalopoda > Octopoda >
Octopodidae > Thaumoctopus mimicus

The Mimic Octopus [2] was discovered in 1998 off the coast of Sulawesi in Indonesia on the bottom of a muddy river mouth.

All octopus species are highly intelligent and change the color and texture of their skin for camouflage to avoid predators. Until the mimic octopus was discovered, however, the remarkable ability to impersonate another animal had never been observed.

Although mimicry is a common survival strategy in nature, the mimic octopus is the first known species to take on the characteristics of multiple species:

  • [3] Sole fish: This flat, poisonous fish is imitated by the mimic octopus by building up speed through jet propulsion as it draws all of its arms together into a leaf-shaped wedge as it undulates in the manner of a swimming flat fish. 
  • [4] Lion fish: To mimic the lion fish, the octopus hovers above the ocean floor with its arms spread wide, trailing from its body to take on the appearance of the lion fish’s poisonous fins. 
  • [5] Sea snakes: The mimic octopus changes color taking on the yellow and black bands of the toxic sea snake as it waves 2 arms in opposite directions in the motion of two sea snakes.

Scientists believe this creature may also impersonate sand anemones, stingrays, mantis shrimp and even jellyfish.

This animal is so intelligent that it is able to discern which dangerous sea creature to impersonate that will present the greatest threat to its current possible predator. For example, scientists observed that when the octopus was attacked by territorial damselfishes, it mimicked the banded sea snake, a known predator of damselfishes.

Source: MarineBio.org  
Cartoon: xkcd

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Life is Too Fast, Too Furious for This Runaway Galaxy
Source: Hubble Space Telescope via NASA Goddard Space Flight Center  

Composite [bottom image] combines NASA/ESA Hubble Space Telescope observations [top]  with data from the Chandra X-ray Observatory [middle]  // Credit: NASA, ESA, CXC

Check out the complete March 4 2014 post from NASA … or the post at the Harvard-Smithsonian Center for Astrophysics [Chandra] site …

Spiral galaxy ESO 137-001, like a dandelion caught in a breeze

The galaxy is zooming toward the upper right of this image, in between other galaxies in the Norma cluster located over 200 million light-years away. The road is harsh: intergalactic gas in the Norma cluster is sparse, but so hot at 180 million degrees Fahrenheit that it glows in X-rays.

The spiral plows through the seething intra-cluster gas so rapidly – at nearly 4.5 million miles per hour — that much of its own gas is caught and torn away. Astronomers call this “ram pressure stripping.” The galaxy’s stars remain intact due to the binding force of their gravity.

Tattered threads of gas, the blue jellyfish-tendrils trailing ESO 137-001 in the image, illustrate the process. Ram pressure has strung this gas away from its home in the spiral galaxy and out over intergalactic space. Once there, these strips of gas have erupted with young, massive stars, which are pumping out light in vivid blues and ultraviolet.

The brown, smoky region near the center of the spiral is being pushed in a similar manner, although in this case it is small dust particles, and not gas, that are being dragged backwards by the intra-cluster medium.

As well as the electric blue ram pressure stripping streaks seen emanating from ESO 137-001, a giant gas stream can be seen extending towards the bottom of the frame, only visible in the X-ray part of the spectrum.

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THE CELL CYCLE AND ITS SAFEGUARDS AGAINST CANCER
SOURCE: PZ Myers (Pharyngula)

TOP IMAGE
Dividing cells follow a cycle.

  • Most cells are in G1 (Gap 1), doing what cells do.
  • Then under control of clock-like changes in specific genes, they can enter the S (synthesis) phase, when their DNA is replicated,
  • followed by a G2 phase (gap 2),
  • and then an actively dividing mitotic or M phase.

Each of these phases has a checkpoint where a battery of proteins survey the state of the cell and either permit the process to proceed, or block it if there are problems.

In extreme cases, the checkpoint proteins can determine that the cell is so irreparably damaged that the only option is suicide, and the cell will self destruct.

MIDDLE IMAGE
This is the process that cancer needs to disrupt if it is to continue; cancer cells typically have damaged DNA or aberrant signals flying everywhere that ought to be triggering all kinds of alarms in the checkpoint system, and either stopping cell division immediately, or activating repair mechanisms that fix the damage, or just killing the corrupted cell immediately.

One of the most critical points in this cycle is called the R or Restriction point.

  • Prior to the R point, the cell is sensitive to external signals that can induce cell division;
  • after this point, the cell no longer pays attention to those signals, because it is on a rigidly programmed track towards completing cell division.

The R point is that last fateful moment of decision before the cell commits to dividing.

BOTTOM IMAGE
Standing at this point is an essential guardian of the cell cycle, pRb. This protein is an inhibitor of cell division, acting as a tumor suppressor gene. It’s the guard at the gate, and it must be satisfied that all is well in the cell before it will allow division to continue.

pRb’s default mode is to stop cell division, but it receives signals from a wide array of pathways that can tell it to stand down and let the process continue.

Control of this gene is complicated because it is so essential to well-regulated cell division: look at it here, standing sentry just above the yellow R point, with all these other pathways talking to it.

I think you can see how this gene can contribute to cancer when it’s defective. Shoot the guard, open the gate wide, and allow cell divisions to proceed unchecked.

This passage is a part of PZ Myers’ much longer critique of an article on the evolution of cancer by two physicists, Paul Davies and Charles Lineweaver, ‘Cancer tumors as Metazoa 1.0: tapping genes of ancient ancestors" (Phys. Biol. 8 015001-015008).

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CONSEQUENCES OF REMOVING LARGE PREDATORS FROM NATURE:
A cascade of failing ecosystems

Review Article: Trophic Downgrading of Planet Earth
James A. Estes, John Terborgh, et al.

“Modern extinctions are largely being caused by a single species, Homo sapiens. From its onset in the late Pleistocene, [this] sixth mass extinction has been characterized by the loss of larger-bodied animals in general and of apex consumers in particular.”

  • [1] “The loss of apex consumers is arguably humankind’s most pervasive influence on the natural world. This is true in part because it has occurred globally and in part because extinctions are by their very nature perpetual, whereas most other environmental impacts are potentially reversible on decadal to millenial time scales.”
  • [2] “The omnipresence of top-down control in ecosystems is not widely appreciated because several of its key components are difficult to observe. The main reason for this is that species interactions, which are invisible under static or equilibrial conditions, must be perturbed if one is to witness and describe them. Even with such perturbations, responses to the loss or addition of a species may require years or decades to become evident." 
  • [3] "Recent research suggests that the disappearance of these animals reverberates further than previously anticipated, with far-reaching effects on processes as diverse as the dynamics of disease; fire; carbon sequestration; invasive species; and biogeochemical exchanges among Earth’s soil, water, and atmosphere.”

Science 15 July 2011: Vol. 333 no. 6040 pp. 301-306 

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Hairy Mycena
Macro Mycography by Steve Axfordsteveax1 ] on Flickr
All Rights Reserved

Closeups of tiny Mycena fungi. This species is (as yet) unidentified and is about 1cm high, though specimens do reach 2-3cm high and up to 4mm across the cap.

The hairs are infertile cells that appear to discourage predation by insects or small animals.

These were found near Booyong in northern NSW and are the first of this group of fungi that have been found in Australia.

Fungi [kingdom] → Basidiomycota [division] → Agaricomycetes [class] →
Agaricales [order] → Mycenaceae [family] → Mycena [genus]

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HISTORY OF MODERN SCIENCE: THE 18th CENTURY “MECHANICS”
Actually, they all seemed to be interested in just about everything.

Daniel Bernoulli (1700-1782) is best known for his work in fluid mechanics, in particular for his discovery that pressure decreases as flow speed increases – a fact that today keeps carburetors running and fixed-wing planes in the air.

Leonhard Euler (1707-1783), Swiss mathematician and physicist sometimes called “the Galileo of mathematical physics,” did ground-breaking work across many fields. He discovered Euler’s number, e, the second most important constant in physics, after pi.

He also introduced much of modern mathematical terminology and notation, for example, the notion of a mathematical function.  Thus, Euler is justifiably remembered as a mathematician. However, he is also known for his work in mechanics, fluid dynamics, optics, astronomy, and music theory.  [wp]

Joseph Fourier (1768-1830) was a pioneer in theories of heat and vibration. The technique he invented for this work – representing complex waves by adding together simpler waves – is now used everywhere in science and engineering.

Thomas Young (1773-1829) pioneered the “double-slit” experiment: shining a light through two narrow slits, he produced a pattern akin to the one produced by two overlapping water waves. This demonstration of the wave nature of light later became central to quantum mechanics.

Young made notable scientific contributions in the fields of vision, light, solid mechanics, energy, physiology, and language. He also advanced European understanding of ancient Egyptian hieroglyphs (notably, those on the famous Rosetta Stone). [wp]

Carl Friedrich Gauss / Gauß (1777-1855), called “the prince of mathematicians” by his contemporaries, is now best remembered for his “normal” (or Gaussian) distributions, which plot how likely things are to vary from average.

A German mathematician and physical scientist, he contributed significantly to many fields - in mathematics: number theory, algebra, statistics, analysis, differential geometry. In physics, he did work in geophysics, electrostatics, astronomy, and optics. [wp]

William Hamilton (1805-1865) reformulated Newtonian mechanics into what is now known as Hamiltonian mechanics. In doing so, he wrote the mathematical language in which modern physics, especially quantum theory, is expressed.

Sir William Rowan Hamilton was an Irish physicist, astronomer, and mathematician, who made important contributions to classical mechanics, optics, and algebra. [wp]

THE SCIENTIFIC TYPOGRAPHIES OF Dr. Prateek Lala: artistic representations of more than 50 influential physicists, cosmologists, and mathematicians – from Anaximander up to Stephen Hawking.

Images and descriptions reprinted (with revisions) from: Perimeter Institute 

NEXT UP: Ohm, Faraday, Maxwell, Röntgen, Tesla