Of the many fascinating phenomena associated with the Sun, solar prominences rate amongst the most spectacular of the observed features. These relatively cool and dense ribbons of plasma are anchored to the Sun’s surface in the photosphere and extend outwards into the Sun’s corona. From their structures and pattern of motion of material, several different types of prominences can be identified: a quiescent prominence may evolve into an active or eruptive prominence and merge into space with violent velocities. This particular prominence rose high into the corona for about 3 hours on December 31, 2012. 
Credit: NASA/SDO

Of the many fascinating phenomena associated with the Sun, solar prominences rate amongst the most spectacular of the observed features. These relatively cool and dense ribbons of plasma are anchored to the Sun’s surface in the photosphere and extend outwards into the Sun’s corona. From their structures and pattern of motion of material, several different types of prominences can be identified: a quiescent prominence may evolve into an active or eruptive prominence and merge into space with violent velocities. This particular prominence rose high into the corona for about 3 hours on December 31, 2012. 

Credit: NASA/SDO

canadian-space-agency:

Breathtaking! Enjoy this beautiful Space Vine time lapse captured by NASA Astronaut Reid Wiseman aboard the ISS. October 5th 2014

Credit: Reid Wiseman/NASA

(Source: vine.co)

Mars Orbiters ‘Duck and Cover’ for Comet Siding Spring Encounter

NASA is taking steps to protect its Mars orbiters, while preserving opportunities to gather valuable scientific data, as Comet C/2013 A1 Siding Spring heads toward a close flyby of Mars on Oct. 19.

The comet’s nucleus will miss Mars by about 82,000 miles (132,000 kilometers), shedding material hurtling at about 35 miles (56 kilometers) per second, relative to Mars and Mars-orbiting spacecraft. At that velocity, even the smallest particle — estimated to be about one-fiftieth of an inch (half a millimeter) across — could cause significant damage to a spacecraft.

NASA currently operates two Mars orbiters, with a third on its way and expected to arrive in Martian orbit just a month before the comet flyby. Teams operating the orbiters plan to have all spacecraft positioned on the opposite side of the Red Planet when the comet is most likely to pass by.

The European Space Agency is taking similar precautions to protect its Mars Express (MEX) orbiter.
  • For more information about the Mars flyby of comet Siding Spring, click here.
Credit: NASA/JPL-Caltech

Comet ‘Siding Spring’ headed for close encounter with Mars

Mars is about to dodge a cosmic snowball on this Sunday. On October 19, Comet Siding Spring will pass within 88,000 miles of Mars – just one third of the distance from the Earth to the Moon! Traveling at 33 miles per second and weighing as much as a small mountain, the comet hails from the outer fringes of our solar system, originating in a region of icy debris known as the Oort cloud.

Comets from the Oort cloud are both ancient and rare. Since this is Comet Siding Spring’s first trip through the inner solar system, scientists are excited to learn more about its composition and the effects of its gas and dust on the Mars upper atmosphere. NASA will be watching closely before, during, and after the flyby with its entire fleet of Mars orbiters and rovers, along with the Hubble Space Telescope and dozens of instruments on Earth. The encounter is certain to teach us more about Oort cloud comets, the Martian atmosphere, and the solar system’s earliest ingredients.

  • For more information, click here

Credit: NASA/GSFC

(Source: youtu.be)

"Man will not always stay on Earth; the pursuit of light and space will lead him to penetrate the bounds of the atmosphere, timidly at first, but in the end to conquer the whole of solar space."

Konstantin Tsiolkovsky

Solar wind and Mars’ Atmosphere

Mars does not have a single unified magnetic field like Earth. It has smaller, more fractured fields which cover the planet and have different intensities and polarities. The absence of magnetic protection allows the supersonic solar wind flow to directly interact with the Martian ionosphere.

The Sun constantly emits high-energy photons (gamma rays) and when one of these photons enters the atmosphere of Mars, it can crash into a molecule, knocking loose an electron and turning it into an ion. These ions can then crash into other molecules and fling atoms everywhere. Some of these atoms can be knocked, or sputtered, into space, causing atmospheric loss. The amount of ionization in the ionosphere varies greatly with the amount of radiation received from the Sun. When the velocity of the solar wind increases, the Martian ionosphere is compressed and the ionopause (a boundary layer between the ionosphere and the solar wind) is displaced to lower altitudes.

Further Reading:

Credit: Chris Smith (HTSI), NASA/Nagoya University

(Source: youtube.com)

"Since, in the long run, every planetary civilization will be endangered by impacts from space, every surviving civilization is obliged to become spacefaring — not because of exploratory or romantic zeal, but for the most practical reason imaginable: staying alive… If our long-term survival is at stake, we have a basic responsibility to our species to venture to other worlds." 
— Carl Sagan - Pale Blue Dot: A Vision of the Human Future in Space (Chapter 21, p.371 )

"Since, in the long run, every planetary civilization will be endangered by impacts from space, every surviving civilization is obliged to become spacefaring — not because of exploratory or romantic zeal, but for the most practical reason imaginable: staying alive… If our long-term survival is at stake, we have a basic responsibility to our species to venture to other worlds." 

Carl Sagan - Pale Blue Dot: A Vision of the Human Future in Space (Chapter 21, p.371 )

Saturn’s Rings and Enceladus

Saturn’s most distinctive feature is the thousands of rings that orbit the planet. Despite the fact that the rings look like continuous hoops of matter encircling the giant planet, each ring is actually made of tiny individual particles. Saturn’s rings consist largely of water ice mixed with smaller amounts of dust and rocky matter. Data from the Cassini spacecraft indicate that the environment around the rings is like an atmosphere, composed principally of molecular oxygen.

The ring system is divided into 5 major components: the G, F, A, B, and C rings, listed from outside to inside (but in reality, these major divisions are subdivided into thousands of individual ringlets). The F and G rings are thin and difficult to see, while the A, B, and C rings are broad and easily visible. The large gap between the A ring and and the B ring is called the Cassini division. One of Saturn’s moons, namely; Enceladus is the source of Saturn’s E-ring. The moon’s geyser-like jets create a gigantic halo of ice, dust, and gas that helps feed Saturn’s E ring.

Enceladus has a profound effect on Saturn and its environment. It’s the only moon in our solar system known to substantially influence the chemical composition of its parent planet. The whole magnetic environment of Saturn is weighed down by the material spewing from Enceladus, which becomes plasma — a gas of electrically charged particles.  This plasma, which creates a donut-shaped cloud around Saturn, is then snatched by Saturn’s A-ring, which acts like a giant sponge where the plasma is absorbed. 

Credit: , NASA/JPL/SSI

Time lapse of the Milky Way rising behind the South African Large Telescope (SALT)
Credit: Anthony Koeslag

Time lapse of the Milky Way rising behind the South African Large Telescope (SALT)

Credit: Anthony Koeslag

for-all-mankind:

Ladies and gentlemen, what you see before you is something that I don’t think has ever been done before. This is a gif of Tuesday’s Lunar Eclipse….seen from the orbit of Mercury.In the image, the Moon can be seen slowly disappearing into Earth’s shadow over the course of an hour. The series of 31 images were taken by the narrow-angle camera on Messenger, orbiting high above Mercury. The Earth and Moon were about 66 million miles from the spacecraft at the time of the Eclipse. In the raw image, Earth is about five pixels across, and the Moon is just over one. The luminosity of the Moon was increased by a factor of 25 in order to make it more visible.While we’ve seen a solar eclipse from the Mir space station before, and a solar eclipse from lunar orbit, I believe this is the first time any eclipse has been seen from the perspective of another planetary body. Absolutely stunning. The full article by the Planetary Society is here.

for-all-mankind:

Ladies and gentlemen, what you see before you is something that I don’t think has ever been done before. This is a gif of Tuesday’s Lunar Eclipse….seen from the orbit of Mercury.

In the image, the Moon can be seen slowly disappearing into Earth’s shadow over the course of an hour. The series of 31 images were taken by the narrow-angle camera on Messenger, orbiting high above Mercury. The Earth and Moon were about 66 million miles from the spacecraft at the time of the Eclipse.

In the raw image, Earth is about five pixels across, and the Moon is just over one. The luminosity of the Moon was increased by a factor of 25 in order to make it more visible.

While we’ve seen a solar eclipse from the Mir space station before, and a solar eclipse from lunar orbit, I believe this is the first time any eclipse has been seen from the perspective of another planetary body. 

Absolutely stunning. The full article by the Planetary Society is here.

Mars Orbiters ‘Duck and Cover’ for Comet Siding Spring Encounter

NASA is taking steps to protect its Mars orbiters, while preserving opportunities to gather valuable scientific data, as Comet C/2013 A1 Siding Spring heads toward a close flyby of Mars on Oct. 19.

The comet’s nucleus will miss Mars by about 82,000 miles (132,000 kilometers), shedding material hurtling at about 35 miles (56 kilometers) per second, relative to Mars and Mars-orbiting spacecraft. At that velocity, even the smallest particle — estimated to be about one-fiftieth of an inch (half a millimeter) across — could cause significant damage to a spacecraft.

NASA currently operates two Mars orbiters, with a third on its way and expected to arrive in Martian orbit just a month before the comet flyby. Teams operating the orbiters plan to have all spacecraft positioned on the opposite side of the Red Planet when the comet is most likely to pass by.

The European Space Agency is taking similar precautions to protect its Mars Express (MEX) orbiter.
  • For more information about the Mars flyby of comet Siding Spring, click here.
Credit: NASA/JPL-Caltech
The Formation and Dynamics of Super-Earth Planets

Super-Earths, objects slightly larger than Earth and slightly smaller than Uranus, have found a special place in exoplanetary science. As a new class of planetary bodies, these objects have challenged models of planet formation at both ends of the spectrum and have triggered a great deal of research on the composition and interior dynamics of rocky planets in connection to their masses and radii.
Being relatively easier to detect than an Earth-sized planet at 1 AU around a G star, super-Earths have become the focus of worldwide observational campaigns to search for habitable planets. With a range of masses that allows these objects to retain moderate atmospheres and perhaps even plate tectonics, super-earths may be habitable if they maintain long-term orbits in the habitable zones of their host stars. Given that in the past two years a few such potentially habitable super-Earths have in fact been discovered, it is necessary to develop a deep understanding of the formation and dynamical evolution of these objects.
This article reviews the current state of research on the formation of super-Earths and discusses different models of their formation and dynamical evolution.

Image Credit: ESO/M. Kornmesser

The Formation and Dynamics of Super-Earth Planets

Super-Earths, objects slightly larger than Earth and slightly smaller than Uranus, have found a special place in exoplanetary science. As a new class of planetary bodies, these objects have challenged models of planet formation at both ends of the spectrum and have triggered a great deal of research on the composition and interior dynamics of rocky planets in connection to their masses and radii.

Being relatively easier to detect than an Earth-sized planet at 1 AU around a G star, super-Earths have become the focus of worldwide observational campaigns to search for habitable planets. With a range of masses that allows these objects to retain moderate atmospheres and perhaps even plate tectonics, super-earths may be habitable if they maintain long-term orbits in the habitable zones of their host stars. Given that in the past two years a few such potentially habitable super-Earths have in fact been discovered, it is necessary to develop a deep understanding of the formation and dynamical evolution of these objects.

This article reviews the current state of research on the formation of super-Earths and discusses different models of their formation and dynamical evolution.

Image Credit: ESO/M. Kornmesser

(Source: eso.org)

txchnologist:

Next-Generation Space Capsule To Endure First Flight Test

On Dec. 4, NASA will launch the Orion capsule on its first space flight aboard the Delta IV Heavy rocket. The vehicle, which is expected to one day carry astronauts to an asteroid and Mars, will perform its first mission unmanned. It is being loaded up with radiation, heat and acceleration sensors, among numerous other instruments, to perform a fact-finding test flight for future exploration.

The four-and-a-half-hour trip will make two orbits around Earth and also test safety systems that will be critical to keeping astronauts alive and comfortable. Orion will go as far as 3,600 miles above Earth to pass through the Van Allen Belt, an area of high radiation levels, to test shielding designed to protect humans from harmful charged particles as they venture deeper into space.

See the full video below.

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Breaking The Supposed Limit In Seeing The Microscopic World Earns Three Chemistry Nobel


txchnologist:

image

by Michael Keller

Three researchers were awarded the 2014 Nobel Prize in Chemistry today for breaking through what was thought to be an absolute optical limit in seeing microscopic objects like viruses and molecules.

The Nobel committee responsible for deciding the winners chose to honor the separate work of two Americans, Eric Betzig and William Moerner, and German Stefan Hell. These scientists pioneered what is called super-resolved fluorescence microscopy, which has opened up a whole new frontier for understanding how life works at the nanoscale. (Txchnologist has previously featured more of Betzig’s groundbreaking work here.)

"I was sitting in my office when the call from Stockholm reached me,” said Hell, who is the director of the Max Planck Institute for Biophysical Chemistry. “I am enormously gratified that my work and that of my colleagues has received the highest distinction for scientific research.”  

Their innovations, using light to excite molecules that have been tagged with fluorescent markers, are now being used around the world. They are letting researchers use visible light to glimpse separate objects that are closer together than what was thought to be the limit of 0.2 microns.  This minimum is called the Abbe diffraction limit, which is half the length of the wavelength of the light used to see something through a microscope.

image

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skunkbear:

There’s another lunar eclipse this year and it’s happening tomorrow night! (That’s Tuesday night — in other words the wee hours of Wednesday morning). Europe and Africa will be left out this time around, but viewers in North America and Asia will get the chance to see the moon pass through the earth’s shadow. Details from NASA here.

This eclipse is extra special because it might be a rare selenelion.

Don’t ask me how to pronounce that word, but here’s what it means: the refraction of light through Earth’s atmosphere makes both sun and moon appear higher in the sky then they really are. So at moonset/sunrise on Wednesday morning, a few lucky observers east of the Mississippi might glimpse the sun and the eclipsed moon AT THE SAME TIME! Geometrically impossible, and well worth setting your alarms for.

I put approximate moonset times in this GIF, but you should look up the specific schedule for your location here.