Awesome Close-Ups of the Sun

Awesome Close-Ups of the Sun



The sun (not the earth!) is the center of our solar system. Here are some interesting facts of this quintessential planet to live on earth that we so easily take for granted.

* Containing more than 99.8% of the total mass of the Solar System, the Sun is by far the largest object in the Solar System.
* 109 Earths would be required to even fit across the Sun’s disk, and the Sun’s interior could hold over 1.3 million Earths.
* Within the core of the Sun, the temperature (15,000,000 K) and pressure (340 billion times Earth’s air pressure at sea level) of it is so intense that nuclear reactions actually take place.
* The Sun’s energy output, produced by these nuclear fusion reactions, is approximately 3.86e33 ergs/second or 386 billion billion megawatts.
* This energy, released as heat as well as light, takes a million years to reach the surface.
* The Sun also emits low density streams of particles, also known as the solar wind. These winds blow through the solar system at 450 km/sec and consist mostly of electrons and protons.
* The Sun consists of the core, photosphere, chromosphere and corona, each with differing temperatures and components.
* Existing for about 4 and a half billion years, it has burnt up about half of the hydrogen in its core. This leaves the Sun’s life expectancy to 5 billion more years, at which time, the Sun’s elements will “swell” up, swallow Earth, and eventually die off into a small white dwarf.

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Martian Skies!

June 19th announcement by NASA of the discovery of water ice on Mars by its Phoenix Lander probe made big news everywhere. The discovery involved the observation of water ice sublimating into the air - that is, the water went from solid to vapor state without reaching the liquid stage. The Martian atmosphere has perfect conditions for sublimation - extremely thin, dry and cold. How cold? Well, you can check the Live Martian Weather Report, with data from a station on board the Phoenix Lander. Today will see a high temperature of a toasty -26 degrees F.

What more do we know about Mars' atmosphere? It's hundreds of times thinner than Earth's atmosphere and is made of 95% carbon dioxide, 3% nitrogen, 1.6% argon, and contains traces of oxygen, water, and methane. We also know, from observations that it can support dust storms, dust devils, clouds and gusty winds. With an amazing number of six current live probes exploring Mars (two rovers, a lander, and three orbiters), there are many thousands ofimages available. Only a few, however show atmospheric phenomena. Presented here are some of the best images of Martian atmosphere (and beyond) in action.

High, wispy clouds cover a large portion of Mars, seen in this, the first true-colour image of Mars generated with the OSIRIS orange (red), green and blue color filters. The image was acquired by an instrumenton the ESA's Rosetta probe on Feb. 24, 2007 from a distance of about 240,000 km. Image resolution is about 5 km/pixel. (Credits: ESA © 2007 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA)

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Mars' northern orange sky and horizon, seen by NASA's Phoenix Mars Lander. The lander's solar panel and Robotic Arm with a sample in the scoop are also visible. The image was taken by the lander's Surface Stereo Imager looking west during Phoenix's Sol 16 (June 10, 2008), or the 16thMartian day after landing. The image was taken just before the sample was delivered to the Optical Microscope. (NASA/JPL-Caltech/University of Arizona/Texas A&M University)

The brownish gray sky at sunset as it would be seen by an observer on Mars - true color mosaic taken by Mars Pathfinder on sol 24 (June 22, 1996) The sky near the sun is a pale blue color. (NASA/JPL)

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High ice cloud over Mars' limb. This composite of red and blue Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images acquired on 6 July 2005 shows an isolated water ice cloud extending more than 30 kilometers (more than 18 miles) above the Martian surface. Clouds such as this are common in late spring over the terrain located southwest of the Arsia Mons volcano. (NASA/JPL/Malin Space Science Systems)

Clouds over crater - the dust storm season in the southern hemisphere of Mars was well underway. This image of an unnamed crater southeast of Hellas Basin shows the encroachment of a storm in the region. Image acquired in 2001 by Mars Odyssey orbiter (17 meter/pixel resolution). (NASA/JPL/ASU)

Dust devil from above. This image taken by the Hi-RISE Camera aboard NASA's Mars Reconnaissance Orbiter catches a dust devil blowing across theMartian surface. Dust devils generally form in the afternoon because the sunlight needs sufficient time to warm the surface. When this image was taken, the local time was about 3:08 p.m. The bright material is the dust within the vortex, and a dark shadow cast by the dust devil is visibleto the left. The diameter of this dust devil is about 200 meters, but at the surface it is probably much smaller. Based on the length of the shadow in this image, the dust devil is on the order of 500 meters tall. (NASA/JPL/University of Arizona)

Martian skies seen above a rolling horizon in this image, part of a larger image called the "McMurdo" panorama, taken in the Martian winter of 2006 by NASA's Mars Exploration Rover Spirit. The tracks in the soil are from Spirits wheels as it rolled through the area earlier. (NASA/JPL/Cornell)

Clouds above the rim of "Endurance Crater" in this image from NASA's Mars Exploration Rover Opportunity. These clouds occur in a region of strong vertical shear. The cloud particles (ice in thismartian case) fall out, and get dragged along away from the location where they originally condensed, forming characteristic streamers. Opportunity took this picture with its navigation camera during the rover's 269thmartian day (Oct. 26, 2004). (NASA/JPL)

Early Spring Dust Storms at the North Pole of Mars. Early spring typically brings dust storms to northern polar Mars. As the north polar cap begins to thaw, the temperature difference between the cold frost region and recently thawed surface results in swirling winds. The choppy dust clouds of several dust storms are visible in this mosaic of images taken by the Mars Global Surveyor spacecraft in 2002. The white polar cap is frozen carbon dioxide. (NASA/JPL/Malin Space Science Systems)

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An exaggerated color image mosaic of images from NASA's Mars Rover Opportunity. The clouds can be composed of either carbon dioxide ice or water ice, and can move swiftly across the sky. (NASA/JPL/Cornell)

Large dust storms cover much of Mars' surface in this July, 2001 image, acquired by NASA's Mars Global Surveyor Mars Orbiter Camera. By early July, themartian atmosphere was so hazy that opportunities for high resolution imaging of the planet were very limited. (NASA/JPL/Malin Space Science Systems)

The air is certainly thick enough to fill a parachute. On May 25th, 2008, the HiRISE camera onboard the Mars Reconnaissance Orbiter acquired this dramatic oblique image of the arrival of its sister probe from NASA, the Phoenix Lander, descending on its parachute. Phoenix and its parachute can be barely seen in the larger image with 10 km wide crater informally called "Heimdall" in the background. Although it appears that Phoenix is descending into the crater, it is actually about 20 kilometers in front of the crater. Given the position and pointing angle of MRO, Phoenix is at about 13 km above the surface, just a few seconds after the parachute opened. (NASA/JPL/University of Arizona)

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On May 19th, 2005, NASA's Mars Exploration Rover Spirit captured this stunning view as the Sun sank below the rim of Gusev crater on Mars. This Panoramic Camera mosaic was taken around 6:07 in the evening of the rover's 489th martian day, or sol. Spirit was commanded to stay awake briefly after sending that sol's data tothe Mars Odyssey orbiter just before sunset. The image is a false color composite, showing the sky similar to what a human would see, but with the colors slightly exaggerated. (NASA/JPL/Texas A&M/Cornell)

Higher in the Martian skies, we see one of its two moons. The HiRISE camera onboard the Mars Reconnaissance Orbiter acquired this dramatic view of the Martian moon, Phobos, on 23 March 2008, from a distance of 6,800 kilometers. The illuminated part of Phobos is about 21 km across. The most prominent feature is the large impact crater Stickney, in the upper left. With a diameter of 9 km, it is the largest feature on Phobos. (NASA/JPL/University of Arizona)

Even higher in the Martian sky, the Earth and Moon hang in space, as seen from Mars. The HiRISE camera onboard the Mars Reconnaissance Orbiter acquired this image at 5:20 a.m. MST on October 3rd, 2007, at a range of 142 million kilometers, while orbiting Mars

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>> Most fascinating Galaxies of the Universe <<

Supernova 1987A

Two decades ago, astronomers spotted one of the brightest exploding stars in more than 400 years: a doomed star, called Supernova 1987A. This image shows the entire region around the supernova. The most prominent feature in the image is a ring with dozens of bright spots. A shock wave of material unleashed by the stellar blast is slamming into regions along the ring's inner regions, heating them up, and causing them to glow. The ring, about a light-year across, was probably shed by the star about 20,000 years before it exploded. In the next few years, the entire ring will be ablaze as it absorbs the full force of the crash. The glowing ring is expected to become bright enough to illuminate the star's surroundings, providingastronomers with new information on how the star expelled material before the explosion. The image was taken in December 2006 with Hubble's Advanced Camera for Surveys. (Credit: NASA, ESA, and R. Kirshner; Harvard-Smithsonian Center for Astrophysics)

Galaxy NGC 1512

A barred spiral galaxy located some 30 million light years away toward the constellation Horologium, Galaxy NGC 1512 is bright enough to be seen with amateur telescopes. The galaxy is some 70,000 light years across, which is nearly as large as our own Milky Way galaxy. The core of the galaxy is remarkable for its "circumnuclear" starburst ring, which is an amazing circle of young star clusters that spans some 2400light years across. Galaxy "starbursts" are episodes of vigorous formation of new stars and are found in various galaxy environments.

Galaxy NGC 3370

A dusty spiral galaxy located some 98 million light years away toward the constellation Leo, the center of NGC 3370 shows well delineated dust lanes and an uncommonly ill-defined nucleus. This view of NGC 3370 was obtained by the Hubble Space Telescope using the Advanced Camera for surveys and is sharp enough to identify individual Cepheid variable stars in the galaxy. Cepheid variable stars are used to establish extragalactic distances. In 1994, a Type Ia sypernova exploded in NGC 3370. (Credit: NASA, The Hubble Heritage Team and A. Riess; STScI)

M81

The big and beautiful spiral galaxy M81, in the northern constellation Ursa Major, is one of the brightest galaxies visible in the skies of planet Earth. This superbly detailed view reveals its bright nucleus, grand spiral arms and sweeping cosmic dust lanes with a scale comparable to the Milky Way. Hinting at a disorderly past, a remarkable dust lane runs straight through the disk, below and right of the galactic center, contrary to M81's other prominent spiral features. The errant dust lane may be the lingering result of a close encounter between M81 and its smaller companion galaxy, M82. Scrutiny of variable stars in M81 (aka NGC 3031) has yielded one of the best determined distances for an external galaxy -- 11.8 million light-years.

Hoag's Object

A non-typical galaxy of the type known as a ring galaxy, the appearance of Hoag's Object has interested amateur astronomers as much as its uncommon structure has fascinated professionals. Is this one galaxy or two? This question came to light in 1950 when astronomer Art Hoag chanced upon this unusual extragalactic object. On the outside is a ring dominated by bright blue stars, while near the center lies a ball of much redder stars that are likely much older. Between the two is a gap that appears almost completely dark. How Hoag's Object formed remains unknown, although similar objects have now been identified and collectively labeled as a form of ring galaxy. Genesis hypotheses include a galaxy collision billions of years ago and perturbative gravitational interactions involving an unusually shaped core. The above photo taken by theHubble Space Telescope in July 2001 reveals unprecedented details of Hoag's Object and may yield a better understanding. Hoag's Object spans about 100,000light years and lies about 600 million light years away toward the constellation of Serpens. Coincidentally, visible in the gap is yet another ring galaxy that likely lies far in the distance.

The Sombrero Galaxy

The Sombrero Galaxy (also known as M104 or NGC 4594) is an unbarred spiral galaxy in the constellation Virgo. It has a bright nucleus, an unusually large central bulge, and a prominent dust lane in its inclined disk. The dark dust laneand the bulge give this galaxy the appearance of a sombrero. The galaxy has an apparent magnitude of +9.0, making it easily visible with amateur telescopes. The large bulge, the central supermassive black hole,and the dust lane all attract the attention of professional astronomers.

Black Eye Galaxy

A spiral galaxy in the Coma Berenices constellation, Messier 64, the famous "Black Eye" galaxy or the "Sleeping Beauty galaxy," has a spectacular dark band of absorbing dust in front of the galaxy's bright nucleus. It is well known among amateurastronomers because of its appearance in small telescopes.

2MASX J00482185-2507365 occulting pair

The 2MASX J00482185-2507365 occulting pair is a pair of overlapping spiral galaxies found in the vicinity of NGC 253, the Sculptor Galaxy. Both galaxies are more distant than NGC 253, with the background galaxy, 2MASX J00482185-2507365, lying at redshift z=0.06, and the foreground galaxy lying between NGC 253 and the background galaxy (0.0008 <>

The Whirlpool Galaxy

Also known as Messier 51a, M51a, or NGC 5194, the Whirlpool Galaxy is an interacting grand-design spiral galaxy located at a distance of approximately 23 million light-years in theconstellation Canes Venatici. It is one of the most famous spiral galaxies in the sky. The galaxy and its companion (NGC 5195) are easily observed by amateur astronomers, and the two galaxies may even be seen with binoculars. The Whirlpool Galaxy is also a popular target for professional astronomers , who study it to further understanding of galaxy structure (particularly structure associated with the spiral arms) and galaxy interactions.

Grand spiral galaxy

Also known as NGC 123, this fascinating galaxy is dominated by millions of bright stars and dark dust, caught up in a gravitational swirl of spiral arms rotating about the center. Open clusters containing bright blue stars can be seen sprinkled along these spiral arms, while dark lanes of dense interstellar dust can be seen sprinkled between them. Less visible, but detectable, are billions of dim normal stars and vast tracts of interstellar gas, together wielding such high mass that they dominate the dynamics of the inner galaxy. Invisible are even greater amounts of matter in a form we don't yet know - pervasive dark matter needed to explain the motions of the visible in the outer galaxy.

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