Universe Today

July 23, 2013December 23, 2015 by Elizabeth Howell

Spacesuit Water Leak Prompts NASA Mishap Investigation

Italian astronaut Luca Parmitano during a spacesuit fit check before his mission. Credit: NASA

In the wake of a spacesuit water leak that sent two astronauts back to the airlock early during a spacewalk last week, NASA has convened a board to look at “lessons learned” from the mishap.

The cause of the leak, which filled Luca Parmitano’s helmet with water, is still being investigated. Some media reports say it may have been a fault within the spacesuit’s cooling system. NASA stated it plans to “develop a set of lessons learned from the incident and suggest ways to prevent a similar problem in the future.”

Chairing the board will be Chris Hansen, the International Space Station’s chief engineer at NASA’s Johnson Space Center in Houston. The other four members, who are all from NASA, include:

Mike Foreman, NASA astronaut, Johnson Space Center;
Richard Fullerton, International Space Station safety and mission assurance lead, Office of Safety and Mission Assurance, NASA headquarters;
Sudhakar Rajula, human factors specialist, Johnson Space Center;
Joe Pellicciotti, chief engineer, NASA Engineering and Safety Center, Goddard Space Flight Center.

The July 16 spacewalk stopped early at 1 hour, 32 minutes, far shorter than the crew’s planned 6.5-hour outing. All of the tasks can be easily pushed off to another time, NASA has said. The astronauts were preparing data cables and power for a Russian laboratory module that should reach the station by early 2014, among other tasks.

ISS Astronauts had to scramble to get Luca Parmitano out of his spacesuit after water leaked inside the suit, covering his face. Via NASA TV.

During and immediately after the spacewalk, NASA said the crew was in no immediate danger. A few days afterwards, Parmitano reassured officials at the European Space Agency. “Guys, I am doing fine and thanks for all the support. I am really okay and ready to move on,” he said, as reported in an ESA blog post.

Still, there was so much water inside the helmet that after a time, Parmitano had trouble hearing and communicating with his crewmates. “Squeeze my hand if you’re fine,” fellow EVA member Chris Cassidy said to Parmitano during the spacewalk.

NASA also noted there is an engineering analysis happening that is “focused on resolving equipment trouble in an effort to enable U.S. spacewalks to resume.” The board, by contrast, will be looking at aspects such as quality assurance, flight control, operations and maintenance with an eye to improving NASA human spaceflight activities in general.

NASA did not immediately release a date by which it expects the investigation to finish. Meanwhile, at least one news outlet reported that the agency is rushing some spacesuit repair tools on to a Russian Progress supply ship that will leave Kazakhstan for the International Space Station on Saturday.

Source: NASA

July 23, 2013December 23, 2015 by Ken Kremer

Sneak Peeks of the Earth and Saturn Panorama from Cassini on July 19

The Day the Earth Smiled: Sneak Preview
In this rare image taken on July 19, 2013, the wide-angle camera on NASA’s Cassini spacecraft has captured Saturn’s rings and our planet Earth and its moon in the same frame. Image Credit: NASA/JPL-Caltech/Space Science Institute
See below our wider context mosaic of the Earth, Saturn and its majestic rings[/caption]

Breathtaking raw images of the Earth and Saturn system snapped by NASA’s Cassini spacecraft on July 19 during the worldwide ‘Wave at Saturn’ campaign are streaming back across 1 billion miles of interplanetary space.

Science team members are now busily processing the images to create individual color composites and a panoramic view of the ‘pale blue dot’ and the entire Saturnian system.

NASA just released the first individual color composite focusing on Earth – see above. And its spectacular!

See below our preliminary mosaic showing the Earth in context with nearly half of Saturn and floating in between its incomparably majestic rings.

Partial context mosaic of the Earth and Saturn taken by NASA’s Cassini orbiter on July 19, 2013. This mosaic was assembled from five wide angle camera raw images. Credit: NASA/JPL-Caltech/Ken Kremer/Marco Di Lorenzo — Partial context mosaic of the Earth and Saturn taken by NASA’s Cassini orbiter on July 19, 2013. This mosaic was assembled from five wide angle camera raw images and offers a sneak peek of the complete panorama. Credit: NASA/JPL-Caltech/Ken Kremer/Marco Di Lorenzo

To capture all of Saturn and its wide swath of rings, Cassini’s wide angle camera snapped a mosaic of 33 footprints.

“At each footprint, images were taken in different spectral filters for a total of 323 images,” says Carolyn Porco, Cassini Imaging Team leader of the Space Science Institute in Boulder, Colo.

Cassini took the pictures of Earth between 2:27 and 2:42 p.m. PDT on Friday, July 19 from a distance of about 898 million miles (1.44 billion kilometers) away from the home to every human being that has ever lived.

The images show the Earth and the Moon as dots barely about a pixel wide but do reveal the ‘pale blue dot’ that is home to all of humanity and our whitish colored neighbor.

Coincidentally, the first humans (Neil Armstrong and Buzz Aldrin) set foot on the Moon 44 years ago nearly to the day of Cassini’s new images on July 20, 1969.

Distant views of the Earth from our robotic explorers, especially from the outer reaches of our Solar System, are few and far between, and are therefore events for space and astronomy enthusiasts and everyone else to savor.

“One of the most exciting Cassini events in 2013 will be the unusual opportunity on July 19 to image the whole Saturn system as it is backlit by the sun,” explained Linda Spilker, Cassini project scientist of NASA’s Jet Propulsion Laboratory, Pasadena, Calif.

“With Saturn covering the harsh light of the sun, we will be gathering unique ring science and also catching a glimpse of our very own home planet.”

Cassini previously took an absolutely fabulous mosaic of Saturn and Earth back in 2006 that stands as one of the landmark images of the space age.

Besides being picturesque, such mosaics also serve science. For example, the 2006 image “revealed that the dusty E ring, which is fed by the water-ice plume of the moon Enceladus, had unexpectedly large variations in brightness and color around its orbit,” says Spilker.

“We’ll want to see how that looks seven Earth years and a Saturnian season later, giving us clues to the forces at work in the Saturn system. We’ll do this analysis by collecting data from our visual and infrared mapping spectrometer, composite infrared mapping spectrometer and ultraviolet imaging spectrograph in addition to the imaging cameras.”

This simulated view from NASA's Cassini spacecraft shows the expected positions of Saturn and Earth on July 19, 2013, around the time Cassini will take Earth's picture. Cassini will be about 898 million miles (1.44 billion kilometers) away from Earth at the time. That distance is nearly 10 times the distance from the sun to Earth. Image credit: NASA/JPL-Caltech — This simulated view from NASA’s Cassini spacecraft shows the expected positions of Saturn and Earth on July 19, 2013, around the time Cassini will take Earth’s picture. Cassini will be about 898 million miles (1.44 billion kilometers) away from Earth at the time. That distance is nearly 10 times the distance from the sun to Earth. Image credit: NASA/JPL-Caltech

“July 19 marked the first time people on Earth had advance notice their planet’s portrait was being taken from interplanetary distances,” says NASA.

I waved fondly at Saturn and hope you had the chance to wave at Saturn from all across the globe. NASA reports that nearly 20,000 participated in organized events. Countless others waved too.

Cassini was launched in 1997 and achieved orbit at Saturn in 2004. The mission is scheduled to continue until 2017 when it will commit a suicide death dive into the gas giant.

“We can’t see individual continents or people in this portrait of Earth, but this pale blue dot is a succinct summary of who we were on July 19,” said Spilker in a NASA statement.

“Cassini’s picture reminds us how tiny our home planet is in the vastness of space, and also testifies to the ingenuity of the citizens of this tiny planet to send a robotic spacecraft so far away from home to study Saturn and take a look-back photo of Earth.”

Ken Kremer

JPL Waves at Saturn As NASA's Cassini spacecraft turned its imaging cameras to Earth, scientists, engineers and visitors at NASA's Jet Propulsion Laboratory, Pasadena, Calif., gathered to wave at our robotic photographer in the Saturn system on July 19, 2013. Credit: NASA/JPL-Caltech — JPL Waves at Saturn
As NASA’s Cassini spacecraft turned its imaging cameras to Earth, scientists, engineers and visitors at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., gathered to wave at our robotic photographer in the Saturn system on July 19, 2013. Credit: NASA/JPL-Caltech

July 22, 2013April 26, 2016 by Shannon Hall

The Latest from Mars: Dried up Riverbed May Have Flowed into an Ancient Ocean

An artist's rendition of what water on Mars may have looked like. Source Credit: NASA

When it comes to Mars, the hot topic of study is water – a prerequisite for life.

While liquid water is currently not stable on the surface of Mars, there is extensive evidence that it may have been in the past. Astronomers have discovered dried up riverbeds, lake deltas, and evidence of widespread glaciers – to name but a few examples.

However, evidence for a massive standing body of water, such as an ocean, is hard to come by. Early climate models struggle to create circumstances under which liquid water would be stable at all. Nonetheless, an ocean spanning the northern lowlands (approximately one third of the planet) has been long hypothesized.

Scientists at Caltech may have just now confirmed this long-held hope in finding recent evidence for a vast Martian ocean.

The region under investigation is known as Aeolis Dorsa – a plain located at the border between the northern lowlands and the southern highlands. This plain contains many ridges, which are interpreted as ancient river channels.

“These ‘inverted’ channels are now elevated because the coarse sand and gravel carried by the channels is more resistant to erosion than the surrounding mud and silt making up the floodplain material,” Dr. Roman DiBiase, lead author on the study, told Universe Today.

Satellite images of Aeolis Dorsa were collected using the HiRISE camera aboard the Mars Reconnaissance Orbiter. The resolution was so precise scientists could distinguish features as small as 25 centimeters – an impressive feat even when compared to images of the Earth.

For certain locations “repeat pictures taken with a slight offset enable the creation of stereo-images from which we can determine the relative elevations of features on the planet’s surface,” explains DiBiase. This impressive technique led to high-resolution topographic models, allowing the team to analyze the geometry and patterns of these inverted channels in unprecedented detail.

Not only do the channels spread out toward the end, they also slope steeply downward, forming a delta – a sedimentary deposit that forms where rivers flow into lakes or oceans.

While deltas have been identified on Mars before, all lie within distinct topographic boundaries, such as an impact crater. This is the most compelling evidence for a delta leading into an unconfined region – an ocean.

Final proof of a Martian ocean will advance our knowledge of the intricate interplay between water, climate, and life. “The history of water on Mars has implications not only for the evolution of Martian climate, but also for learning about the early evolution of Earth and Earth’s climate,” explains DiBiase.

As always, further research is needed. Perhaps in the nearby future the Mars Reconnaissance Orbiter and Curiosity will compliment each other quite well – the orbiter taking images from above while Curiosity plays in the dirt, gathering samples in the riverbed.

The study was published in the Journal of Geophysical Research and may be found here.

July 22, 2013December 23, 2015 by David Dickinson

Super-Moon Monday: The 3rd (& Final?) Act

The gibbous Moon rising rising over the Andes Mountains in Chile. (Credit: @WladimirPulgarG/Flickr).

“Once more into the breach, my dear friends…”

Such a quip may be deemed appropriate as we endured the media onslaught this past weekend for the third and final perigee Full Moon of 2013.

Tonight, on Monday, July 22^nd, the Moon reaches Full at 18:15 Universal Time (UT)/4:15 PM EDT. This is only 21.9 hours after reaching perigee, or the closest point in its orbit at 358,401 kilometres from the Earth on the Sunday evening at 20:28 UT. Continue reading “Super-Moon Monday: The 3rd (& Final?) Act”

July 22, 2013December 23, 2015 by Elizabeth Howell

Expedition 37/38’s Tips For Surviving Long Voyages in Space

Russian cosmonaut Oleg Kotov (left), Expedition 37 flight engineer and Expedition 38 commander; along with NASA astronaut Michael Hopkins (center) and Russian cosmonaut Sergey Ryazanskiy, both Expedition 37/38 flight engineers. Credit: NASA

NASA wants to bring its astronauts outside of Earth. It recently recruited a new astronaut class for deep space voyages. It’s talking about picking up asteroids and possibly heading to the moon or Mars in the distant future. But there are a heck of a lot of steps to do before anyone can head into space for long periods of time.

The agency and Roscosmos are preparing for a one-year voyage to the International Space Station in 2015 that will add to the limited set of data on people being in space consecutively for a year, or longer. You can bet there will be reams of information collected on sleep habits, bone loss, muscle shrinkage, eye pressure and other health factors of concern.

How about the psychological side? The next space station crew to launch gave some hints about how their training prepares them to live cheek-by-jowl in a tiny space for six months.

The mission’s main goal:

The main goal is to put the station in a good condition, and also for the Russian segment, to [install] the new module, MLM (Multipurpose Laboratory Module.) We’re all targeted to this job. Me especially, being the commander of the station, I have the responsibility of the whole crew and their success and also for their psych [psychological] atmosphere. That’s really what I want to do. — Oleg Kotov, Expedition 37 flight engineer, Expedition 38 commander and preparing for his third spaceflight

Receiving advice from past crews:

Sometimes it’s the little things in terms of how to deal with, for example … the food and your clothes and supplies. Other times it’s trying to make sure you’re focusing on the critical items, and not necessarily getting caught up in all the little details [because] you’re going to be there for such a long amount of time. — Michael Hopkins, Expedition 37/38 flight engineer and rookie astronaut

The Mars 500 long-duration mission vs. flying to the space station:

Mars 500 was really aimed at science. Most of the station [work] is mostly of the safety of the crew and the safety of the station, and then the [next priority is] science. But it also was a great experience to see, psychologically, the space station can be isolating, and how great the influence of this psychology is on the crew. So that was really the experience. Being commander there helps me a lot in my training for real flight.” — Sergey Ryzansky, commander of a 105-day segment as part of phase two of the Mars 500 program, Expedition 37/38 flight engineer and rookie cosmonaut

Michael Hopkins, Expedition 37/38 flight engineer, during spacewalk training. Credit: NASA

Communications with Mission Control:

Sometimes you ask a question or an item from the ground, and just realizing that you’re not always going to get that answer right away. Sometimes it takes some time for them to determine what the right answer is. — Hopkins

The challenge for other planets:

[I study] how to develop countermeasure means for flights on another planets. After 200 days, for example, flying in space, then we need human beings to work in a spacesuit on the surface of other planets, in different gravity. — Ryzansky

July 22, 2013March 16, 2017 by Fraser Cain

How Hot is the Sun?

The Sun is hot, really hot. How hot hot really is, depends on which part you’re talking about:

The sun has a core, a middle, a surface, and an atmosphere.

Starting from the inside out…

There’s the core, where the pressure and temperature are so great that atoms of hydrogen are fused into helium. Every second, 600 million tons of material go through this conversion, releasing vast amounts of gamma radiation. This is the hottest natural place in the Solar System, reaching temperatures of 15 million degrees Celsius. Photons generated at the core of the Sun are emitted and absorbed countless times over thousands of years on their journey to reach the surface.

Outside the core is the radiative zone. Here, temperatures dip down to where fusion reactions can no longer occur, ranging from 7 million down to 2 million degrees Celsius.

Next on our journey outwards from the centre of the Sun, is the convective zone, where bubbles of plasma carry the heat to the surface like a giant lava lamp. Temperatures at the bottom of the convective zone are 2 million degrees.

Finally, the surface, the part of the star that we can see. This is where the temperature is a relatively cool 5,500 degrees Celsius.

Here’s the strange part, as you move further away from the Sun into its atmosphere, the temperature rises again. Above the surface is the chromosphere, where temperatures rise back up to 20,000 degrees Celsius.

Then there is the corona, the Sun’s outer atmosphere. The corona as a wispy halo around the Sun, visible during eclipses, that stretches millions of kilometres out into space. In the corona, the gases from the Sun are superheated to more than a million degrees – some parts of can even rise to 10 million degrees Celsius.

How can the atmosphere of the Sun get hotter than regions inside it? Astronomers aren’t really sure, but there are two competing theories. It’s possible that waves of energy are released from the surface of the Sun, sending their energy high into the solar atmosphere. Or perhaps the Sun’s magnetic field releases energy into the corona as currents collapse and reconnect.

There are space missions in the works right now to help answer this baffling mystery, so we might have an answer soon.

Stars can get much hotter or colder than our Sun. From the coldest, dimmest red dwarf stars to the hottest blue giants; it’s an amazing Universe out there.

References:
Solar Probe Plus Mission
Solar Orbiter Mission

July 22, 2013December 23, 2015 by Katrina Cain

Giveaway: The Universe in the Rearview Mirror by Dave Goldberg

Enter to win one of two free copies of The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality. How?

In order to be entered into the giveaway drawing, just put your email address into the box at the bottom of this post (where it says “Enter the Giveaway”) before Sunday, July 28, 2013. We’ll send you a confirmation email, so you’ll need to click that to be entered into the drawing.

We’re only going to use these email addresses for Universe Today giveaways/contests and announcements. We won’t be using them for any other purpose, and we definitely won’t be selling the addresses to anyone else. Once you’re on the giveaway notification list, you’ll be able to unsubscribe any time you like.

July 22, 2013December 23, 2015 by Tyler Simko

Book Review: “The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality” by Dave Goldberg

It’s not every day that you find a Physics book that is both wonderfully thorough and wildly entertaining – but, then again, it’s not every day that Dave Goldberg publishes a book; he’d be quite the busy boy if that was the case. But as writer for the fantastic Ask a Physicist column on io9.com (seriously, check it out), professor and director of undergraduate studies at Drexel University, Slate and LA Times contributor, husband and father – he’s plenty busy already. As an avid reader of Ask A Physicist, I was already familiar with his entertaining writing style – but getting to enjoy it in a full-length book was quite the treat.

Enter The Universe In The Rearview Mirror. Although many recent physics books focus almost entirely on the oddities of quantum mechanics, Goldberg steps outside the now almost tiresome discussions of randomness and Schrodinger’s Cat to enlighten readers on a topic less often discussed, but just as (if not more) fascinating – symmetry. Goldberg’s perusal of symmetry extends far beyond your Elementary School-inspired notions of bilaterally symmetric shapes into questions about the origins, shape and inevitable fate of the universe – among many others!

At most times in Rearview Mirror, Goldberg’s style feels more like a discussion than a book – it’s as if your delightfully nerdy friend from college (the one with a knack for identifying stars, he’s convinced it’s a total turn-on) came over for dinner one night to talk about his favorite topic – the mysteries of the cosmos. Even with the conversational essence, Goldberg is sure to never get bogged down in scientific jargon,instead he frequently relies on allusions and analogies to get his point across.

In the book’s first five pages alone Goldberg makes creative allusions to Star Wars, Angels & Demons, Isaac Asimov, The Incredible Hulk, Twilight , and Star Trek. In the world of science writing since The Big Bang Theory, countless authors have tried to appeal to the “nerdy” sub-genre, but the allusions and comparisons in most books typically seem forced, even irrelevant at times. Perhaps due to his extensive teaching experience, this is never the case with Goldberg’s writing – every allusion is spot-on and fascinating, even Feynman-like at times. Never before had I thought of Lewis Carroll’s Alice jumping down the rabbit hole when discussing a black hole, and now I’ll never be able to think of taking the plunge without doing so.

Throughout the slightly-over-300-page-journey, readers explore fascinating conundrums posed as the subtitle of every chapter, concerning topics like Antimatter (“why there is something rather than nothing”), The Cosmological Principle (“why it is dark at night”) and quantum Spin (“why you aren’t a sentient cloud of helium and what a spoonful of neutron star would do to you”). Although each chapter does seek to answer these questions, the excitement comes from Goldberg’s masterful leadership – he paves the way with insightful analogies and surprisingly digestible descriptions of complex concepts (no equations allowed).

Once the journey is over, readers will not only have a thorough understanding of how symmetry truly shapes our universe, but also a plethora of exciting dinner conversations sure to spice up any date – “Hey, did you know that poker can teach us a lot about entropy?”

July 22, 2013December 23, 2015 by Nancy Atkinson

Gallery: Atlas 5 Launches US Navy’s Heavyweight MUOS-2 Satellite into Orbit

The launch of the Mobile User Objective System satellite (MUOS-2), a Navy communications satellite aboard a United Launch Alliance Atlas 5 rocket, on July 19, 2013. Credit and copyright: John O'Connor/Nasatech.com

A heavyweight next generation of military communications satellites was launched on July 19, 2013 from Cape Canaveral Air Force Station, in Florida. The Mobile User Objective System (MUOS)-2 satellite launched on board a United Launch Alliance Atlas 5 rocket, and is now in the process of reaching to its final geostationary orbit.

Images here are courtesy of John O’Connor from the Nasatech website.

The satellite weighed nearly 7,000 kg (15,000 pounds) making it one of the heaviest payloads ever launched with an Atlas 5.

See more launch images below:

It will take about eight days to maneuver MUOS-2 into geostationary orbit according to Captain Paul Ghyzel, the Navy’s MUOS program manager.

The US Navy says the new satellite is the second satellite in a new system that supports a worldwide, multi-Service population of users in the ultra-high frequency band. The system provides increased communications capabilities, and is designed to support users that require greater mobility, higher data rates and improved operational availability.

The MUOS-1 launched in February 2012 and there will be five such satellites in the system that are described as being like orbital cell phone towers to span the globe.

The network will cost a total of $5 billion.

Arcing out on an easterly course to geosync orbit the Atlas V/MUOS-2 vehicle accelerates. Credit and copyright: John O'Connor/Nasatech.net — Arcing out on an easterly course to geosync orbit the Atlas V/MUOS-2 vehicle accelerates. Credit and copyright: John O’Connor/Nasatech.net

See more MUOS-2 launch images from John at Nasatech.net.

July 21, 2013December 23, 2015 by Jason Major

What the Earth and Moon Look Like From Saturn

Earth and Moon imaged from Cassini on July 19, 2013

Did you smile and wave at Saturn on Friday? If you did (and even if you didn’t) here’s how you — and everyone else on Earth — looked to the Cassini spacecraft, 898.4 million miles away.

Hope you didn’t blink!

The image above is a color-composite made from raw images acquired by Cassini in red, green, and blue visible light wavelengths. Some of the specks around the edges are background stars, and others are the result of high-energy particle noise, of which some have been digitally removed.

The Moon is the bright dot just below and to the left of Earth. (An original raw image can be seen here.)

UPDATE 7/22: See the *official* NASA images here.

Cassini acquired the images while capturing views of Saturn in eclipse against the Sun between 22:24:00 UTC on July 19 and 02:43:00 UTC on July 20 (6:24 to 10:43 pm EDT July 19.) On Cassini time, the Earth imaging took place between 22:47:13 UTC (6:47:13 pm EDT) and 23:01:56 UTC (7:01:56 pm EDT) on the 19th.

Full mosaic arrangement acquired by Cassini on July 19-20 UTC. (NASA/JPL-Caltech/SSI) — Full mosaic arrangement acquired by Cassini on July 19-20 UTC. Earth was positioned just below the planet. (NASA/JPL-Caltech/SSI)

The world was invited to “Wave at Saturn” beginning 5:27 pm EDT on Friday — which allowed enough time for the photons from a waving world to actually reach Cassini’s camera just beyond Saturn, 1.44 billion kilometers away. (Did you wave? I did!) It was the first time Earth’s population was made aware beforehand that their picture would be taken from such a cosmic distance.

A crowd gathered on the mall at NASA's Jet Propulsion Laboratory in Pasadena to wave at Saturn on July 19 (NASA/JPL-Caltech) — A crowd gathered on the mall at NASA’s Jet Propulsion Laboratory in Pasadena to wave at Saturn on July 19 (NASA/JPL-Caltech)

The image of our planet and moon, seen as merely a couple of bright points of light against the blackness of space, recalls Sagan’s poignant “pale blue dot” passage from Cosmos…

“From this distant vantage point, the Earth might not seem of any particular interest. But for us, it’s different. Consider again that dot. That’s here, that’s home, that’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every “superstar,” every “supreme leader,” every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.

The “pale blue dot” of Earth captured by Voyager 1 in Feb. 1990 (NASA/JPL)

The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds.

Our posturings, our imagined self-importance, the delusion that we have some privileged position in the universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves.

The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand.

It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we’ve ever known.”

— Carl Sagan (1934–1996)

A full mosaic of Cassini’s imaging of Saturn silhouetted against the Sun is expected in the coming weeks.

UPDATE: Here’s another RGB color composite, made from raw images acquired with Cassini’s wide-angle camera. It shows a view of Saturn and the rings in eclipse as seen from below and behind, backlit by the Sun. Earth is the bright point light near the center. (See original here.)

fdslkfhkdshklfa — Raw image (RGB composite) of Saturn in eclipse with Earth in the distance — just a pale blue dot. (NASA/JPL-Caltech/SSI. Composite by J. Major.)

Images: NASA/JPL-Caltech/Space Science Institute. Composites by Jason Major.