Some of the Best Pictures of the Planets in our Solar System

The Eight Planets of our Solar System. Credit: IAU

Our Solar System is a pretty picturesque place. Between the Sun, the Moon, and the Inner and Outer Solar System, there is no shortage of wondrous things to behold. But arguably, it is the eight planets that make up our Solar System that are the most interesting and photogenic. With their spherical discs, surface patterns and curious geological formations, Earth’s neighbors have been a subject of immense fascination for astronomers and scientists for millennia.

And in the age of modern astronomy, which goes beyond terrestrial telescopes to space telescopes, orbiters and satellites, there is no shortage of pictures of the planets. But here are a few of the better ones, taken with high-resolutions cameras on board spacecraft that managed to capture their intricate, picturesque, and rugged beauty.

Mercury, as imaged by the MESSENGER spacecraft, revealing parts of the never seen by human eyes. Image Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Mercury, as imaged by the MESSENGER spacecraft, revealing parts never before seen by human eyes. Image Credit: NASA/Johns Hopkins University/Carnegie Institution of Washington

Named after the winged messenger of the gods, Mercury is the closest planet to our Sun. It’s also the smallest (now that Pluto is no longer considered a planet. At 4,879 km, it is actually smaller than the Jovian moon of Ganymede and Saturn’s largest moon, Titan.

Because of its slow rotation and tenuous atmosphere, the planet experiences extreme variations in temperature – ranging from -184 °C on the dark side and 465 °C on the side facing the Sun. Because of this, its surface is barren and sun-scorched, as seen in the image above provided by the MESSENGER spacecraft.

A radar view of Venus taken by the Magellan spacecraft, with some gaps filled in by the Pioneer Venus orbiter. Credit: NASA/JPL
A radar view of Venus taken by the Magellan spacecraft, with some gaps filled in by the Pioneer Venus orbiter. Credit: NASA/JPL

Venus is the second planet from our Sun, and Earth’s closest neighboring planet. It also has the dubious honor of being the hottest planet in the Solar System. While farther away from the Sun than Mercury, it has a thick atmosphere made up primarily of carbon dioxide, sulfur dioxide and nitrogen gas. This causes the Sun’s heat to become trapped, pushing average temperatures up to as high as 460°C. Due to the presence of sulfuric and carbonic compounds in the atmosphere, the planet’s atmosphere also produces rainstorms of sulfuric acid.

Because of its thick atmosphere, scientists were unable to examine of the surface of the planet until 1970s and the development of radar imaging. Since that time, numerous ground-based and orbital imaging surveys have produced information on the surface, particularly by the Magellan spacecraft (1990-94). The pictures sent back by Magellan revealed a harsh landscape dominated by lava flows and volcanoes, further adding to Venus’ inhospitable reputation.

Earth viewed from the Moon by the Apollo 11 spacecraft. Credit: NASA
Earth viewed from the Moon by the Apollo 11 spacecraft. Credit: NASA

Earth is the third planet from the Sun, the densest planet in our Solar System, and the fifth largest planet. Not only is 70% of the Earth’s surface covered with water, but the planet is also in the perfect spot – in the center of the hypothetical habitable zone – to support life. It’s atmosphere is primarily composed of nitrogen and oxygen and its average surface temperatures is 7.2°C. Hence why we call it home.

Being that it is our home, observing the planet as a whole was impossible prior to the space age. However, images taken by numerous satellites and spacecraft – such as the Apollo 11 mission, shown above – have been some of the most breathtaking and iconic in history.

The first true-colour image of Mars from ESA’s Rosetta generated using the OSIRIS orange (red), green and blue colour filters. The image was acquired on 24 February 2007 at 19:28 CET from a distance of about 240 000 km. Credit: MPS for OSIRIS Team MPS/UPD/LAM/ IAA/ RSSD/ INTA/ UPM/ DASP/ IDA
The first true-colour image of Mars taken by the ESA’s Rosetta spacecraft on 24 February 2007. Credit: MPS for OSIRIS Team MPS/UPD/LAM/ IAA/ RSSD/ INTA/ UPM/ DASP/ IDA

Mars is the fourth planet from our Sun and Earth’s second closest neighbor. Roughly half the size of Earth, Mars is much colder than Earth, but experiences quite a bit of variability, with temperatures ranging from 20 °C at the equator during midday, to as low as -153 °C at the poles. This is due in part to Mars’ distance from the Sun, but also to its thin atmosphere which is not able to retain heat.

Mars is famous for its red color and the speculation it has sparked about life on other planets. This red color is caused by iron oxide – rust – which is plentiful on the planet’s surface. It’s surface features, which include long “canals”, have fueled speculation that the planet was home to a civilization.

Observations made by satellites flybys in the 1960’s (by the Mariner 3 and 4 spacecraft) dispelled this notion, but scientists still believe that warm, flowing water once existed on the surface, as well as organic molecules. Since that time, a small army of spacecraft and rovers have taken the Martian surface, and have produced some of the most detailed and beautiful photos of the planet to date.

Jupiter's Great Red Spot and Ganymede's Shadow. Image Credit: NASA/ESA/A. Simon (Goddard Space Flight Center)
Jupiter’s Great Red Spot and Ganymede’s Shadow. Image Credit: NASA/ESA/A. Simon (Goddard Space Flight Center)

Jupiter, the closest gas giant to our Sun, is also the largest planet in the Solar System. Measuring over 70,000 km in radius, it is 317 times more massive than Earth and 2.5 times more massive than all the other planets in our Solar System combined. It also has the most moons of any planet in the Solar System, with 67 confirmed satellites as of 2012.

Despite its size, Jupiter is not very dense. The planet is comprised almost entirely of gas, with what astronomers believe is a core of metallic hydrogen. Yet, the sheer amount of pressure, radiation, gravitational pull and storm activity of this planet make it the undisputed titan of our Solar System.

Jupiter has been imaged by ground-based telescopes, space telescopes, and orbiter spacecraft. The best ground-based picture was taken in 2008 by the ESO’s Very Large Telescope (VTL) using its Multi-Conjugate Adaptive Optics Demonstrator (MAD) instrument. However, the greatest images captured of the Jovian giant were taken during flybys, in this case by the Galileo and Cassini missions.

Saturn and its rings, as seen from above the planet by the Cassini spacecraft. Credit: NASA/JPL/Space Science Institute. Assembled by Gordan Ugarkovic.
Saturn and its rings, as seen from above the planet by the Cassini spacecraft. Credit: NASA/JPL/Space Science Institute/Gordan Ugarkovic

Saturn, the second gas giant closest to our Sun, is best known for its ring system – which is composed of rocks, dust, and other materials. All gas giants have their own system of rings, but Saturn’s system is the most visible and photogenic. The planet is also the second largest in our Solar System, and is second only to Jupiter in terms of moons (62 confirmed).

Much like Jupiter, numerous pictures have been taken of the planet by a combination of ground-based telescopes, space telescopes and orbital spacecraft. These include the Pioneer, Voyager, and most recently, Cassini spacecraft.

Uranus, seen by Voyager 2. Image credit: NASA/JPL
Uranus, seen by Voyager 2 spacecraft. Image credit: NASA/JPL

Another gas giant, Uranus is the seventh planet from our Sun and the third largest planet in our Solar System. The planet contains roughly 14.5 times the mass of the Earth, but it has a low density. Scientists believe it is composed of a rocky core that is surrounded by an icy mantle made up of water, ammonia and methane ice, which is itself surrounded by an outer gaseous atmosphere of hydrogen and helium.

It is for this reason that Uranus is often referred to as an “ice planet”. The concentrations of methane are also what gives Uranus its blue color. Though telescopes have captured images of the planet, only one spacecraft has even taken pictures of Uranus over the years. This was the Voyager 2 craft which performed a flyby of the planet in 1986.

Neptune from Voyager 2. Image credit: NASA/JPL
Neptune from Voyager 2. Image credit: NASA/JPL

Neptune is the eight planet of our Solar System, and the farthest from the Sun. Like Uranus, it is both a gas giant and ice giant, composed of a solid core surrounded by methane and ammonia ices, surrounded by large amounts of methane gas. Once again, this methane is what gives the planet its blue color.  It is also the smallest gas giant in the outer Solar System, and the fourth largest planet.

All of the gas giants have intense storms, but Neptune has the fastest winds of any planet in our Solar System. The winds on Neptune can reach up to 2,100 kilometers per hour, and the strongest of which are believed to be the Great Dark Spot, which was seen in 1989, or the Small Dark Spot (also seen in 1989). In both cases, these storms and the planet itself were observed by the Voyager 2 spacecraft, the only one to capture images of the planet.

Universe Today has many interesting articles on the subject of the planets, such as interesting facts about the planets and interesting facts about the Solar System.

If you are looking for more information, try NASA’s Solar System exploration page and an overview of the Solar System.

Astronomy Cast has episodes on all of the planets including Mercury.

Take a Look Through Curiosity’s ChemCam

This (adjusted) image was taken by ChemCam’s Remote Micro-Imager on Sol 15 (NASA/JPL-Caltech/LANL)

While Curiosity has been getting a good look around its landing spot on Mars, taking in the sights and sending back some impressive views of distant hills and Gale Crater’s enormous central peak, it’s also been peering very closely at some tiny targets just meters away — with its head-mounted, laser-powered and much-touted ChemCam.

The images above and below were acquired by ChemCam’s Remote Micro-Imager on August 21, the 15th “Sol” of the mission. A full-sized image accessed from the public MSL mission site, it’s been brightened quite a bit to show the details of the target rocks.

Mounted to Curiosity’s “head”, just above its Mastcam camera “eyes”, ChemCam combines a powerful laser with a telescope and spectrometer that can analyze the light emitted by zapped materials, thereby determining with unprecedented precision what Mars’ rocks are really made of.

So even though the rover hasn’t actually roved anywhere yet, it’s still performing valuable scientific investigations of Mars — without moving a single wheel. (UPDATE: actually, Curiosity has begun to do some roving — here are some images of its first wheel tracks!)

Read: Curiosity Blasts First Mars Rock with Powerful Laser Zapper

Because ChemCam uses a laser, Curiosity can examine many targets — up to a dozen — within a small time period without having to drive right up to them. Even the dustiest rocks won’t pose a problem for ChemCam – one or two zaps with its laser will be enough to vaporize any loose surface material.

In addition to searching for the building blocks of life hidden inside rocks, ChemCam will also serve a precautionary role for future explorers by helping identify the potential toxicity of Mars’ soil and dust. When astronauts one day land on Mars, they are going to get dusty. It’s important to know if Mars’ dust contains anything dangerous like lead, arsenic (and who knows what else!)

See the latest images from the MSL mission — including more ChemCam pictures — here.

Images: NASA/JPL-Caltech/LANL. Edited by J. Major.

New Submillimetre Camera Sheds Light on the Dark Regions of the Universe

A composite image of the Whirlpool Galaxy (also known as M51). The green image is from the Hubble Space Telescope and shows the optical wavelength. The submillimetre light detected by SCUBA-2 is shown in red (850 microns) and blue (450 microns). The Whirlpool Galaxy lies at an estimated distance of 31 million light years from Earth in the constellation Canes Venatici Credit: JAC / UBC / Nasa

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The stars and faint galaxies you see when you look up at the night sky are all emitting light within the visible light spectrum — the portion of the electromagnetic spectrum we can see with our unaided eyes or through optical telescopes. But our galaxy, and many others, contain huge amounts of cold dust that absorbs visible light. This accounts for the dark regions.

A new camera recently unveiled at the James Clerk Maxwell Telescope (JCMT) in Hawaii promises to figuratively shed light on this dark part of the universe. The SCUBA-2 submillimetre camera (SCUBA in this case is an acronym for Submillimetre Common-User Bolometer Array) can detect light at lower energy levels, allowing astronomers to gather data on these dark areas and ultimately learn more about our universe and its formation. 

Light is measurable; its intensity or brightness is measured by photons while colour is measured by the energy of the photons. Red photons have the least energy and violet photons have the most energy. This can also be thought of in terms of wavelengths. Light at longer wavelengths have less energy and light at shorter wavelengths have more energy. This continues beyond the visible light spectrum. As electromagnetic waves get shorter, we get ultraviolet light, x-rays, and gamma rays. As wavelengths get longer, we get infrared light, submillimetre light, and finally radio waves.

Panoramic view of the entire near-infrared sky reveals the distribution of galaxies beyond the Milky Way. Image credit: Thomas Jarrett, IPAC/Caltech.

On the longer end of the electromagnetic spectrum, infrared and radio telescopes have been around for decades helping astronomers understand more about the universe. But this is only part of the picture. The cold dust that absorbs the visible light to create the dark regions seen through optical telescopes is actually absorbing the light’s energy and reemitting it at longer wavelengths in the submillimetre region.

The first submillimetre camera, SCUBA, was designed and constructed at the Royal Observatory in Edinburgh in collaboration with the University of London. In 1997, it was up and running at the JCMT. Observations of submillimetre wavelengths are typically harder to gather — it takes a long time to image a small portion of the sky in this region. Nevertheless, submillimetre observations have already revealed a previously unknown population of distant, dusty galaxies as well as images of cold debris discs around nearby stars. This latter finding could be an indication of the presence of planetary systems.

A team of astronomers has recently developed the camera SCUBA-2 that can probe the submillimetre region with increased speed and much greater detail. But it’s a touchy instrument. Director of the JCMT Professor Gary Davis explains that for SCUBA-2 to detect extremely low energy radiation in the submillimetre region, “the instrument itself needs to be [extremely cold]. The detectors… have to be cooled to only 0.1 degree above absolute zero [–273.05°C], making the interior of SCUBA-2 colder than anything in the Universe that we know of!”

The infant Universe as imaged in the radio wavelength spectrum. Image Credit: NASA/WMAP Science Team.

The camera is a huge step in observational astronomy. Director of the United Kingdom Astronomy Teaching Centre Professor Ian Robson likened the technological leap between early sub-millimetre cameras and SCUBA-2 to the difference between wind-on film cameras and modern digital technology. “It is thanks to the ingenuity and abilities of our scientists and engineers that this immense leap in progress has been achieved,” he said.

Dr Antonio Chrysostomou, Associate Director of the JCMT, explains that SCUBA-2’s first task will be to carry out a series of surveys throughout the sky, mapping sites of star formation within our Galaxy, as well as planet formation around nearby stars. It will also survey our galactic neighbours and look into deep space to sample the youngest galaxies in the Universe. This latter task will be critical in helping astronomers understand how galaxies have evolved since the Big Bang.

The SCUBA-2 camera is housed on the 15 metre (about 50 foot) diameter JCMT situated close to the summit of Mauna Kea, Hawaii, at an altitude of 4092 metres (about 13,425 feet). It is typically used to study our Solar System, interstellar dust and gas, and distant galaxies.

Source: Revolutionary New Camera Reveals Dark Side of the Universe

 

The James Clerk Maxwell Telescope. Image credit: www.jach.hawaii.edu

 

 

Historic Photos Commemorate First and Last Shuttle Crews

From left to right, they are: STS-135 pilot Doug Hurley, STS-1 pilot Robert Crippen, STS-1 commander John Young (a former Gemini and moonwalking Apollo astronaut), STS-135 commander Chris Ferguson, and STS-135 mission specialists Sandy Magnus and Rex Walheim.

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In an historic photo shoot earlier this month, NASA commemorated the space shuttle’s retirement, personifying the thirty-year program with the first and last astronaut crews to fly the vehicle.

The shuttle program has certainly come a long way from STS-1 to STS-135. 

Young and Crippen. The STS-1 crew's official portrait, 1981. Image credit: NASA.

John Young and Robert Crippen launched on STS-1 in the shuttle Columbia on April 12, 1981, twenty years after Yuri Gagarin became the first man to orbit the Earth. It was a shakedown cruise, with the two astronauts spending only two days in orbit. They checked out the spacecraft’s systems, the vehicle’s overall flight worthiness, and made the first runway landing from orbit. The only payload the crew carried was a Development Flight Instrumentation (DFI) package. It contained sensors to measure and record Columbia’s performance in orbit and the stresses it felt during launch, ascent, orbital flight, descent and landing.

Thirty years and two months later, the crew of STS-135 had a much busier mission on their hands. Launched on July 8, 2011 in the Atlantis orbiter, the crew’s primary mission objective was to transfer thousands of pounds of supplies into the International Space Station and take thousands more pounds of unneeded cargo back down to Earth.

Atlantis stayed docked to the ISS for eight of its twelve days in orbit. The crew, along with the Expedition 28 crew that spent close to four months aboard the station, played a real life and oversized version of Tetris to get all the supplies squared away in the ISS’ multi-purpose module.

The crews of STS-135 and Expedition 28 pose with the flag flown in STS-1. Credit: NASA

With the cargo transfer complete, Atlantis undocked from the station on July 19. The crew spent the last two days of the final mission in orbit, deploying experiments and readying the spacecraft for landing. Atlantis touched down on the runway at the Kennedy Spaceflight Centre on July 21.

NASA’s complete image gallery, which includes images of the STS-135 post flight wrap up as well as pictures with the STS-1 crew, highlights the personal strain that runs through manned spaceflight. And it doesn’t stop there. During STS-135’s mission, commander Chris Ferguson presented the ISS’s crew the U.S. flag John Young and Robert Crippen carried into space on STS-1. The flag will remain on display on the station until the next crew that launches from the U.S. retrieves it. After returning to Earth, the flag will be launched again with the first crew to embark on a journey beyond Earth orbit.

The Crews of STS-1 and STS-135. John Young, STS-1 commander, Robert Crippen, STS-1 pilot, with the STS-135 crew of commander Chris Ferguson, pilot Doug Hurley and mission specialists Sandy Magnus and Rex Walheim. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

Best Images from STS-133: Discovery’s Final Mission in Pictures

Discovery leaving the ISS on March 7, 2011 for the final time. Credit: NASA

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As space shuttle Discovery prepares to return home from its final mission to space, let’s take a look back at the STS-133 mission, an historic “last” for the program’s most-traveled shuttle. “I think the legacy that this shuttle has made for herself is just nothing short than cause for celebration,” said mission specialist Michael Barratt during press conference from orbit on March 8.

“It’s going to be sad when it’s over, when we land tomorrow or the next day,” said STS-133 commander Steve Lindsey. “The hardest part of this for me is giving up the capability. It can do everything except leave low-Earth orbit…There is not a single thing wrong with her. Every single system and every piece of every system is working just like it’s brand new.”

After a successful launch, the Remote Manipulator System/Orbiter Boom Sensor System (RMS/OBSS) equipped with special cameras, begins to conduct thorough inspections of the shuttle's thermal tile system on flight day 2. Photo credit: NASA
This view of the nose, the forward underside and crew cabin of the space shuttle Discovery was provided by an Expedition 26 crew member during a survey of the approaching STS-133 vehicle prior to docking with the International Space Station. Credit: NASA
ISS tally ho! A view the space station as Discovery approaches for docking. Compare this image with one below, taken as Discovery departs to see the addition of the PMM. Credit: NASA
Backdropped by a blue and white part of Earth, space shuttle Discovery is featured in this image photographed by an Expedition 26 crew member as the shuttle approaches the International Space Station during STS-133 rendezvous and docking operations. Docking occurred at 2:14 p.m. (EST) on Feb. 26, 2011. A Russian Progress spacecraft docked to the space station is also featured in the image. Credit: NASA
A view of the docked space shuttle Discovery during the STS-133 mission, along with and the Canadian-built robot Dextre, and other parts of the ISS. Credit: NASA
European Space Agency astronaut Paolo Nespoli (left), Expedition 26 flight engineer; and NASA astronaut Steve Bowen, STS-133 mission specialist, are pictured in the Quest airlock of the International Space Station as they prepare for the start of the mission's first spacewalk. Credit: NASA
Astronauts Steve Bowen and Alvin drew work in tandem on one of the truss sections of the ISS during the first spacewalk of the STS-133 mission. Credit: NAS
Astronaut Alvin Drew during the first spacewalk of the STS-133 mission. Credit: NASA

The first spacewalk of the mission lasted six-hours and 34-minutes. Alvin Drew and Steve Bowen installed a power extension cable, move a failed ammonia pump module to the External Stowage Platform 2 on the Quest Airlock for return to Earth at a later date, installed a camera wedge on the right hand truss segment, installed extensions to the mobile transporter rail and exposed the Japanese “Message in a Bottle” experiment to space.

Cady Coleman, Expedition 26 flight engineer, is pictured near a Japanese-designed metal cylinder floating freely in the Destiny laboratory of the International Space Station while space shuttle Discovery remains docked with the station. On Feb. 28, spacewalkers Steve Bowen and Alvin Drew opened and 'filled' the cylinder, named "Message in a Bottle", with space, or rather the vacuum of outer space, and then sealed it to be brought back to Earth with the Discovery crew. Credit: NAS
The newly-attached Permanent Multipurpose Module (PMM) and a docked Russian Soyuz spacecraft. Credit: NASA
NASA astronauts Scott Kelly (foreground), Expedition 26 commander; and Steve Lindsey, STS-133 commander, are pictured in the newly-installed Permanent Multipurpose Module (PMM) of the International Space Station. Credit: NASA
Backdropped by Earth's horizon and the blackness of space, this view shows the Cupola of the International Space Station and a docked Russian Progress spacecraft, taken during the STS-133 mission. Credit: NASA
Nicole Stott, STS-133 mission specialist, is pictured in the Cupola of the International Space Station. Credit: NASA
Alvin Drew, STS-133 mission specialist, is pictured in his sleeping bag, which is attached in the Columbus laboratory of the International Space Station. Credit: NASA
The crews from STS-133 and the ISS Expedition 26 in the newly installed Permanent Multipurpose Module. Credit: NASA

Joint crew photo inside the newest module, the PMM — which is basically a big storage closet for the ISS. The STS-133 crew members, all attired in red shirts(from left)are NASA astronauts Alvin Drew, Eric Boe (below), Nicole Stott, Michael Barratt, Steve Bowen and Steve Lindsey (below). The dark blue-attired Expedition 26 crew members, from bottom left, are NASA astronaut Scott Kelly, European Space Agency astronaut Paolo Nespoli, NASA astronaut Cady Coleman along with Russian cosmonaut Oleg Skripochka. In the center of the photo are Dmitry Kondratyev and Alexander Y. Kaleri.

Russian cosmonaut Dmitry Kondratyev, Expedition 26 flight engineer, moves stowage containers in the Unity node of the International Space Station. Credit: NAS
Alvin Drew works outside during the second EVA of the STS-133 mission. Credit: NASA
Anchored to a Canadarm2 mobile foot restraint, NASA astronaut Steve Bowen works outside the ISS during the second EVA of the STS-133 mission. Credit: NASA
The space shuttle Discovery as seen from the International Space Station, flying over southwestern coast of Morocco in the northern Atlantic. During a post undocking fly-around, the crew members aboard the two spacecraft collected a series of photos of each other's vehicle. Credit: NASA
Backdropped against the blackness of spaec and clouds over Earth, the International Space Station is seen from Discovery as the shuttle departed from the station. Credit: NAS
Disovery departing the ISS for the final time. Credit: NASA

Larger versions of all these images can be found at NASA’s Human Spaceflight website, under the STS-133 gallery.

Click here to see our gallery of launch images for Discovery’s final flight.

Here’s a video recap of the STS-133 mission:

Spitzer, the Wallpaper Factory, Does it Again

Infrared portrait of the Small Magellanic Cloud, made by NASA's Spitzer Space Telescope

At the end of the proverbial day, space-based missions like Spitzer produce millions of observations of astronomical objects, phenomena, and events. And those terabytes of data are used to test hypotheses in astrophysics which lead to a deeper understanding of the universe and our home in it, and perhaps some breakthrough whose here-on-the-ground implementation leads to a major, historic improvement in human welfare and planetary ecosystem health.

But such missions also leave more immediate legacies, in terms of the pleasure they bring millions of people, via the beauty of their images (not to mention posters, computer wallpaper and screen savers, and even inspiration for avatars).

Some recent results from one of Spitzer’s programs – SAGE-SMC – are no exception.

The image shows the main body of the Small Magellanic Cloud (SMC), which is comprised of the “bar” on the left and a “wing” extending to the right. The bar contains both old stars (in blue) and young stars lighting up their natal dust (green/red). The wing mainly contains young stars. In addition, the image contains a galactic globular cluster in the lower left (blue cluster of stars) and emission from dust in our own galaxy (green in the upper right and lower right corners).

The data in this image are being used by astronomers to study the lifecycle of dust in the entire galaxy: from the formation in stellar atmospheres, to the reservoir containing the present day interstellar medium, and the dust consumed in forming new stars. The dust being formed in old, evolved stars (blue stars with a red tinge) is measured using mid-infrared wavelengths. The present day interstellar dust is weighed by measuring the intensity and color of emission at longer infrared wavelengths. The rate at which the raw material is being consumed is determined by studying ionized gas regions and the younger stars (yellow/red extended regions). The SMC is one of very few galaxies where this type of study is possible, and the research could not be done without Spitzer.

This image was captured by Spitzer’s infrared array camera and multiband imaging photometer (blue is 3.6-micron light; green is 8.0 microns; and red is combination of 24-, 70- and 160-micron light). The blue color mainly traces old stars. The green color traces emission from organic dust grains (mainly polycyclic aromatic hydrocarbons). The red traces emission from larger, cooler dust grains.

The image was taken as part of the Spitzer Legacy program known as SAGE-SMC: Surveying the Agents of Galaxy Evolution in the Tidally-Stripped, Low Metallicity Small Magellanic Cloud.

The Small Magellanic Cloud (SMC), and its larger sister galaxy, the Large Magellanic Cloud (LMC), are named after the seafaring explorer Ferdinand Magellan, who documented them while circling the globe nearly 500 years ago. From Earth’s southern hemisphere, they can appear as wispy clouds. The SMC is the further of the pair, at 200,000 light-years away.

Recent research has shown that the galaxies may not, as previously suspected, orbit around our galaxy, the Milky Way. Instead, they are thought to be merely sailing by, destined to go their own way. Astronomers say the two galaxies, which are both less evolved than a galaxy like ours, were triggered to create bursts of new stars by gravitational interactions with the Milky Way and with each other. In fact, the LMC may eventually consume its smaller companion.

Karl Gordon, the principal investigator of the latest Spitzer observations at the Space Telescope Science Institute in Baltimore, Maryland, and his team are interested in the SMC not only because it is so close and compact, but also because it is very similar to young galaxies thought to populate the universe billions of years ago. The SMC has only one-fifth the amount of heavier elements, such as carbon, contained in the Milky Way, which means that its stars haven’t been around long enough to pump large amounts of these elements back into their environment. Such elements were necessary for life to form in our solar system.

Studies of the SMC therefore offer a glimpse into the different types of environments in which stars form.

“It’s quite the treasure trove,” said Gordon, “because this galaxy is so close and relatively large, we can study all the various stages and facets of how stars form in one environment.” He continued: “With Spitzer, we are pinpointing how to best calculate the numbers of new stars that are forming right now. Observations in the infrared give us a view into the birthplace of stars, unveiling the dust-enshrouded locations where stars have just formed.”

Little Galaxy with a Tail (Small Magellanic Cloud imaged by Spitzer)

This image shows the main body of the SMC, which is comprised of the “bar” and “wing” on the left and the “tail” extending to the right. The tail contains only gas, dust and newly formed stars. Spitzer data has confirmed that the tail region was recently torn off the main body of the galaxy. Two of the tail clusters, which are still embedded in their birth clouds, can be seen as red dots.

Source: Spitzer

Cassini Survives Close Encounter of the Death Star Kind!

Cassini's Mimas, from 70,000 km (Credit: NASA/JPL/Space Science Institute)

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On February 13, 2010, Cassini flew by Saturn’s moon Mimas, coming as close as 9,500 km.

It passed directly over Herschel, a giant crater whose creation almost shattered the moon … and which, in its appearance in some earlier images, earned Mimas the nickname “Death Star”, after the iconic Star Wars prop.

The Cassini team has just released some “Raw Previews” of Cassini’s close encounter; time to feast your eyes.

35,000 km-distant Herschel, from Cassini (unprocessed image; credit: NASA/JPL/Space Science Institute)

The Cassini Equinox Mission, of which the Mimas flyby is but a small part, is a joint United States and European endeavor. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA’s Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The imaging team consists of scientists from the US, England, France, and Germany. The imaging operations center and team lead (Dr. C. Porco) are based at the Space Science Institute in Boulder, Colo.
Herschel, from 16,000 km above (unprocessed image; credit: NASA/JPL/Space Science Institute)

Source: CICLOPS (Cassini Imaging Central Laboratory for Operations)

Beautiful Pics

How Cold is Space
Backpacking

Here are some beautiful pics of space and astronomy.

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This is a picture of NASA Mission Specialist Bruce McCandless floating free above the Earth. He was testing out a new backpack that let astronauts perform spacewalks without the need for a cumbersome tether.

Long Shadows on the Lunar Surface
Long Shadows on the Lunar Surface

This is a very oblique angle view of craters on the Moon taken by the crew of Apollo 10 as they circled around the Moon. This was the last mission before astronauts actually landed onto the Moon.

A Moment Frozen in Time
A Moment Frozen in Time

This is a picture of the Sun captured from the surface of Mars. This picture was taken by NASA’s Spirit rover just as the Sun was setting.

Montage of Neptune and Triton
Montage of Neptune and Triton

Here’s a montage of Neptune and its largest moon Triton. These pictures were taken separately by NASA’s Voyager 2 spacecraft when it made its flyby of the planet in 1989. The pictures were then merged together into this mosaic.

Into the Heart of Darkness
Into the Heart of Darkness

This is a photo of the supermassive black hole at the heart of the Milky Way. Well, it’s actually the region around the black hole, known as Sagittarius A*.

We’ve written many articles for Universe Today with beautiful pics. Here’s an image of the Veil Nebula complex from Johannes Schedler, and here’s a picture of NGC 2903 from Warren Keller.

If you’d like more amazing photographs, the best place to look is NASA’s Astronomy Picture of the Day. I also recommend you check out the website for the Hubble Space Telescope.

We’ve recorded many episodes of Astronomy Cast, including one about Hubble. Check it out, Episode 88: The Hubble Space Telescope.

Amazon Rainforest Pictures

Afternoon Clouds In Amazon Rainforest

Here are Amazon forest pictures from space. Satellite observation of the Amazon is the best way to keep track on the ongoing deforestation of the region.

Here’s a cool picture that shows how the Amazon has a dry period too, where the skies have nice fluffy clouds. The Amazon River is up at the top of the image, with some of its other tributaries further down in the picture.

Fires In The Amazon Basin

The next of our Amazon pictures was captured by NASA’s Terra satellite. It’s mostly untouched forest, but you can see regions of deforestation near the top center. The red dots in the image are fires, likely used to clear forested land.

Deforestation In Mato Grosso

This is a photograph of the Mato Grosso region of the Amazon forest. Officials in Brazil think that almost 50% of the deforestation in the Amazon in recent years occurred in this region.

Fires and Smoke In Brazil from Space

Here’s a beautiful image of the Amazon captured by the crew of the space shuttle. You can see large clouds of smoke coming from deforestation activities in the region, as farmers clear land for cattle.

Deforestation Picture from Space

Here’s an image that shows the amount of deforestation going on in the Amazon rainforest. You can see the alternating strips of forest and clearcuts as farmers expand deeper into the forest.

We’ve written several episodes about the Amazon rainforest for Universe Today. Here’s an article about the world’s widest river, and here’s a story about how deforestation in Brazil is affecting the local climate.

If you’d like more info on the Amazon, check out this article on Amazon deforestation from NASA, and how the Amazon is very resilient to drought.

We’ve recorded several episodes of Astronomy Cast which are on this topic. Check out Episode 151: Atmospheres.

Nebula Wallpaper

Nebula Wallpaper

Want a nebula wallpaper to put as the background image of your computer desktop? Here’s a handful of nebula images. To make any of them your computer’s background image, just click on the image to see a larger version. Then right-click on the image and choose to set the image as your desktop background.

The nebula wallpaper is the Flame Nebula, captured by the European Southern Observatory. Also known as NGC 2024, it’s a famous nebula located about 1,500 light-years away in the constellation of Orion. The bright star at the top of the image is Alnitak, one of the belt stars of Orion.


Crab Nebula

This is a wallpaper image of the Crab Nebula taken by the Hubble Space Telescope. Also known as M1, the Crab Nebula is the results of a supernova explosion that occurred almost 1000 years ago. Astronomers in 1054 AD reported a star brighting in the sky, and lasting for a few weeks before it dimmed again. That was the supernova that went on to create the Crab Nebula.


Butterfly Nebula

This is a wallpaper of the Butterfly Nebula (or NGC 6302) captured by Hubble. This is a planetary nebula, the result of a dying star blasting out its outer layers into space. This is what our own Sun might do in about 7 billion years from now after it becomes a red giant star.


Ring Nebula

This is Hubble Space Telescope image of the Ring Nebula, also known as M57. It’s actually a planetary nebula, where the outer layers of a dying star are puffed out into space. The Ring Nebula is located about 4000 light-years away, and measures about 500 times larger than the Solar System.


Carina Nebula

This is the Carina Nebula, photographed by the Hubble Space Telescope. This is just one pillar of gas and dust in the nebula, measuring 2 light-years across. It’s located about 7,500 light years from Earth.

We’ve written many articles about nebulae for Universe Today. Here’s an article about dust in the Iris Nebula, and here’s an article about Hubble images of the Helix Nebula.

If you’d like more information on nebulae, check out NASA’s Photo Gallery of Nebulae, and here’s a link to the Hubblesite Homepage for recent stories and images.

We’ve recorded an episode of Astronomy Cast all about nebulae. Listen here, Episode 111: Nebulae.