Sunday, October 26, 2014

Beautiful Images of the October 23, 2014 Partial Solar Eclipse

Beautiful Images of the October 23, 2014 Partial Solar Eclipse:

The partial solar eclipse of October 23, 2014, with a giant sunspot visible. Credit and copyright: Derek Mellott.


The partial solar eclipse of October 23, 2014, with a giant sunspot visible. Credit and copyright: Derek Mellott.
“The Sun looks like it has a bite taken out of it!” said one enthusiastic viewer of the partial solar eclipse on October 23. Although I only had my paper plate pinhole projector that I shared with a crowd of folks (you can see an image of it near the bottom of the images here), the funny-looking Sun projected onto the plate definitely looked like a cookie with bite out of it or a clipped fingernail. But thankfully, as the Moon moved in front of the Sun today, legions of astrophotographers were out to take fantastic images of the eclipse. And the gigantic sunspot named AR 2192 made a cameo appearance as well. Enjoy the gallery below!

Thanks to everyone who uploaded images to our Flickr page or shared their images on Twitter.

An artistic view of the Partial Solar Eclipse, October 23, 2014. Credit and copyright: A Nartist.


An artistic view of the Partial Solar Eclipse, October 23, 2014. Credit and copyright: A Nartist.
The setting Sun, shadowed by the Moon and spotted with intense magnetic activity on October 23, 2014. Credit and copyright: Tavi Greiner.


The setting Sun, shadowed by the Moon and spotted with intense magnetic activity on October 23, 2014. Credit and copyright: Tavi Greiner.
Solar eclipse over the Flatirons near Boulder, Colorado. A syzygy, with the Earth and Moon simultaneously transiting the Sun. Credit and copyright: Alex Parker.


Solar eclipse over the Flatirons near Boulder, Colorado. A syzygy, with the Earth and Moon simultaneously transiting the Sun. Credit and copyright: Alex Parker.
Partial Solar Eclipse of October 23, 2014 at 280mm. Credit and copyright: Forrest Tanaka.


Partial Solar Eclipse of October 23, 2014, at 280mm. Credit and copyright: Forrest Tanaka.
The sun sets while still in eclipse as seen from Duluth, Minn. Thursday evening October 23. Credit and copyright: Bob King.


The sun sets while still in eclipse as seen from Duluth, Minn., Thursday evening October 23. Credit and copyright: Bob King.
The solar eclipse on October 23, 2014, showing the Sun dotted by sunspots and airplane contrails. Credit and copyright: Greg Hogan.


The solar eclipse on October 23, 2014, showing the Sun dotted by sunspots and airplane contrails. Credit and copyright: Greg Hogan.
A cloudy closeup of the partial solar eclipse on October 23, 2014. Credit and copyright: JCC_Starguy on Flickr.


A cloudy closeup of the partial solar eclipse on October 23, 2014. Credit and copyright: JCC_Starguy on Flickr.
The cusps of the Sun's disk are just visible above the horizon as the solar eclipse of October 23, 2014 fades out over Iowa. Credit and copyright: Alan Boyle/NBC News.


The cusps of the Sun’s disk are just visible above the horizon as the solar eclipse of October 23, 2014, fades out over Iowa. Credit and copyright: Alan Boyle/NBC News.
A partial solar eclipse is visable just before sunset Thursday, Oct. 23, 2014, in Arlington, VA. Photo Credit: (NASA/Bill Ingalls)


A partial solar eclipse is visable just before sunset Thursday, Oct. 23, 2014, in Arlington, VA. Photo Credit: (NASA/Bill Ingalls)
The partial solar eclipse as viewed through a paper plate pinhole projector. Credit, copyright and pinhole: Nancy Atkinson.


The partial solar eclipse as viewed through a paper plate pinhole projector. Credit, copyright and pinhole: Nancy Atkinson.
OK, here’s what it looked like outside the SETI Institute. pic.twitter.com/ucqWzJeB4c

— SethShostak (@SethShostak) October 24, 2014
The Moon is beginning to eclipse an enormous filament on the Sun http://t.co/oFH0aPfEay via @Slooh pic.twitter.com/JbM3OHI4wQ

— Alan Duffy (@astroduff) October 23, 2014
What we did for fun… hundreds of crescent suns from a collapsible “spaghetti strainer” #eclipse: pic.twitter.com/ih9vvHUwMI

— David Dickinson (@Astroguyz) October 23, 2014
PHOTOS: Partial Solar Eclipse: https://t.co/nZowDIognC #SanJose #BayArea #SolarEclipse pic.twitter.com/Kdu4XIMoa0

— Chris Calubaquib (@ChrisAstro) October 24, 2014
See more great images on Universe Today’s Flickr pool page.

You Could Fit All the Planets Between the Earth and the Moon

You Could Fit All the Planets Between the Earth and the Moon:

by Fraser Cain on October 25, 2014
You could fit all the planets within the average distance to the Moon.


You could fit all the planets within the average distance to the Moon.


I ran into this intriguing infographic over on Reddit that claimed that you could fit all the planets of the Solar System within the average distance between the Earth and the Moon.


I’d honestly never heard this stat before, and it’s pretty amazing how well they tightly fit together.

But I thought it would be a good idea to doublecheck the math, just to be absolutely certain. I pulled my numbers from NASA’s Solar System Fact Sheets, and they’re a little different from the original infographic, but close enough that the comparison is still valid.

The average distance from the Earth to the Moon is 384,400 km. And check it out, that leaves us with 4,392 km to spare.

So what could we do with the rest of that distance? Well, we could obviously fit Pluto into that slot. It’s around 2,300 km across. Which leaves us about 2,092 km to play with. We could fit one more dwarf planet in there (not Eris though, too big).

The amazing Wolfram-Alpha can make this calculation for you automatically: total diameter of the planets. Although, this includes the diameter of Earth too.

A nod to CapnTrip on Reddit for posting this.

Thursday, October 23, 2014

Want to See Some Pretty Pictures? Here are the Winners of the 2014 Photo Nightscape Awards

Want to See Some Pretty Pictures? Here are the Winners of the 2014 Photo Nightscape Awards:

by Nancy Atkinson on October 16, 2014

PNA 2014 - First in the 'Espoir' (hope) category: ‘Milky way over Baobabs.’ Credit and copyright: Mohammad Taha Ghouckkanly/PNA.


PNA - First prize in the'Pro' Category: ‘Night at Tatio Geysers.' Credit and copyright: Jean-Marc Lecleire/PNA


PNA – First prize in the’Pro’ Category: ‘Night at Tatio Geysers.’ Credit and copyright: Jean-Marc Lecleire/PNA
We told you earlier this year about an astrophotography contest held by Ciel et Espace Photos in France, called the Photo Nightscape Awards. This is the first year of the competition and the winners have now been announced — and they are gorgeous!

They had two categories: pro and ‘espoir’ (amateur, or literally, ‘hope,’) and more than 100 photographers from around the world participated. Above is the winning entry for the pro category, a wonderful shot of a geyser field located in the Andes Mountains of northern Chile with a beautiful night sky overhead, taken by Jean-Marc Lecleire.

See a video compilation of the winners and other submissions, below, along with more beautiful images:





PNA 2014 – First in the ‘Espoir’ (hope) category: ‘Milky way over Baobabs.’ Credit and copyright: Mohammad Taha Ghouckkanly/PNA.
The organizers of the contest said they are looking for “astrophotography that mixes photographic art and poetry. The judge for the contest was Miguel Claro, whose astrophotography we feature often here on Universe Today.

Other winners were 1st prize ‘Pro': Tommy Eliassen; 2nd prize ‘Pro': Mohammad Taha Ghouchkanlu for the “Baobabs” image, below; 1st prize ‘Espoir': Pascal Colas; 2nd prize ‘Espoir': Jérémy Gachon; 1st prize in young astronomers 9-12 group was Louis-Hadrien Gros and 2nd 9-12 was Justin Galant. 1st prize in the young astronomers 13-17 group was Tess Gautier, 2nd prize ’13-17.

You can see all the winning photos at the website here, where you can also learn about next year’s competition.

PNA 'Pro' Category 2014: ‘Still Untouched’ Credit and copyright: Rogelio Bernal Andreo/PNA.


PNA ‘Pro’ Category 2014: ‘Still Untouched’ Credit and copyright: Rogelio Bernal Andreo/PNA.

Titan’s Majestic Mirror-Like Lakes Will Come Under Cassini’s Scrutiny This Week

Titan’s Majestic Mirror-Like Lakes Will Come Under Cassini’s Scrutiny This Week:

This colorized mosaic from NASA's Cassini mission shows the most complete view yet of Titan's northern land of lakes and seas. Saturn's moon Titan is the only world in our solar system other than Earth that has stable liquid on its surface. The liquid in Titan's lakes and seas is mostly methane and ethane. Image credit: NASA/JPL-Caltech/ASI/USGS


This colorized mosaic from NASA’s Cassini mission shows the most complete view yet of Titan’s northern land of lakes and seas. Saturn’s moon Titan is the only world in our solar system other than Earth that has stable liquid on its surface. The liquid in Titan’s lakes and seas is mostly methane and ethane. Image credit: NASA/JPL-Caltech/ASI/USGS
There’s a very early-stage NASA concept to take a submarine and dive into a lake of Titan, that moon of Saturn that has chemistry that could prove to be a similar precursor to what eventually formed life on Earth. The moon has weather and a hydrological system and an atmosphere, making it an exciting location for astrobiologists.

Luckily for scientists, the Cassini spacecraft beams back regular updates on what it sees at Titan. And this week comes yet another opportunity, as the machine whizzes by the moon to look for “mirror-like surface echoes” in a lake-filled region in Titan’s northern sector.

Principal among the targets will be Kraken Mare, a liquid hydrocarbon sea that is about five times the size of Lake Superior in North America. It’s an astounding 154,000 square miles (400,000 square kilometers). On this pass, Cassini is going to sail over the eastern area of the sea.

“Measurements of the absolute strength of the echo and its polarization properties, when detectable, yield important information about the surface status (liquid/solid), surface reflectivity, surface dielectric constant and implied composition, and surface roughness,” Cassini’s website says in a description of the T-106 flyby, which will take place Thursday (Oct. 23).

Saturn's moon Titan with Tethys hovering in the background. Image taken by the Cassini spacecraft. Credit: NASA/JPL/Space Science Institute


Saturn’s moon Titan with Tethys hovering in the background. Image taken by the Cassini spacecraft. Credit: NASA/JPL/Space Science Institute
This is the second-to-last flyby Cassini will have of Titan in 2014, with the last one coming Dec. 10. In that case, the focus will be learning more about Titan’s atmosphere to learn more about measurement differences obtained by instruments on Cassini.

This past week, meanwhile, Titan has been busy looking at Saturn. It examined a northern aurora, looked at the planet’s F ring, and also searched for small satellites.

Scientists have been working at Saturn for the past 10 years with the Cassini mission, which is now entering a new phase as Saturn enters northern summer. This is expected to produce more changes on Titan, such as winds picking up, as more sunlight strikes the surface and atmosphere.



About 

Elizabeth Howell is the senior writer at Universe Today. She also works for Space.com, Space Exploration Network, the NASA Lunar Science Institute, NASA Astrobiology Magazine and LiveScience, among others. Career highlights include watching three shuttle launches, and going on a two-week simulated Mars expedition in rural Utah. You can follow her on Twitter @howellspace or contact her at her website.

How to Safely Enjoy the October 23 Partial Solar Eclipse

How to Safely Enjoy the October 23 Partial Solar Eclipse:

The partially eclipsed sun sets over Island Lake north of Duluth, Minn. on May 20, 2012. Credit: Jim Schaff


The partially eclipsed sun sets over Island Lake north of Duluth, Minn. on May 20, 2012. Similar sunset photo opportunities will happen again during Thursday’s partial solar eclipse. Credit: Jim Schaff
2014 – a year rich in eclipses. The Moon dutifully slid into Earth’s shadow in April and October gifting us with two total lunars. Now it’s the Sun’s turn. This Thursday October 23 skywatchers across much of the North America and Mexico will witness a partial solar eclipse. From the eastern U.S. the eclipse will reach maximum around the time of sunset, making for dramatic picture-taking opportunities. Further west, the entire eclipse will occur with the sun up in the afternoon sky. Either way, you can’t go wrong.

During a solar eclipse, the orbiting Moon passes between the Sun and Earth completely blocking the Sun from view as shown here. In Thursday's partial eclipse, the moon will pass a little north of a line connecting the three orbs, leaving a piece of the sun uncovered for a partial eclipse. Credit: Wikipedia


During a solar eclipse, the orbiting Moon passes between the Sun and Earth completely blocking the Sun from view as shown here. In Thursday’s eclipse, the moon will pass a little north of a line connecting the three orbs, leaving a portion of the sun uncovered. To view a partial solar eclipse, a safe solar filter is necessary. Credit: Wikipedia
Solar eclipses occur at New Moon when the Moon passes between the Sun and the Earth and blocks the Sun from view. During a total solar eclipse, the Sun, Earth and Moon are exactly aligned and the Moon completely hides the brilliant solar disk. Partial eclipses occur when the Moon passes slight north or south of the line connecting the three bodies, leaving a slice of the Sun uncovered. For that reason, a safe solar filter is required to protect your eyes at all times. We’ll delve into that in a minute, but first let’s look at the particulars of this eclipse.

Map showing times and percentage of the sun covered during Thursday's partial solar eclipse. Times are Pacific Daylight - add 1 hour for MDT, 2 hours for CDT and 3 hours for EDT. Credit: NASA, F. Espenak with additions by the author


Map showing times and percentage of the sun covered during Thursday’s partial solar eclipse. Times are Pacific Daylight – add 1 hour for MDT, 2 hours for CDT and 3 hours for EDT. Interpolate between the lines to find your approximate viewing time. The arc marked A shows where the eclipse begins at sunset; B = Maximum eclipse at sunset and C = Eclipse ends at sunset. Credit: NASA, F. Espenak,with additions by Bob King
Nowhere will this eclipse be total. At best, polar bears and musk oxen in Canada’s Nunavut Territory near Prince of Wales Island will see 81% of the sun covered at sunset at maximum eclipse. Most of the rest of us will witness about half the Sun covered with the northern U.S. getting around 65% and the southern states  closer to 40%.  In Minneapolis, Minn. for instance, the eclipse begins at 4:23 p.m. CDT, reaches a maximum of 62% at 5:35 p.m. and continues on till sunset at 6:14 p.m. For times, coverage and other local circumstances for your town, click over to  U.S. cities and cities in Canada and Mexico.

Safe solar filters for looking at the sun come in several different varieties. Read down to learn more about each kind. Photo: Bob King


Safe solar filters come in several varieties ranging from plastic glasses to a #14 welder’s glass for visual observation and snug-fitting optical filters that fit over the end of a telescope. Credit: Bob King
There are several ways to observe a partial eclipse safely, but they all start with this credo: Never look directly at the Sun. Dangerous ultraviolet and infrared light focused on your retinas will damage your vision for life. Nothing’s worth that risk. Happily, filters and indirect viewing methods are available. Eclipse glasses fitted with mylar or polymer lenses are a great choice. I’ve used them all but my favorite’s still the classic #14 welder’s glass because it slips in the pocket easily and takes a beating. Make sure it’s a #14, not a #13 or lower.

You can mount binoculars on a tripod, cover one lens with a lenscap and project the sun's image safely onto a sheet of white cardboard. Credit: Bob King


You can mount binoculars on a tripod, cover one lens with a lenscap and project the sun’s image safely onto a sheet of white cardboard. Credit: Bob King
Telescopes should be outfitted with an optical mylar or aluminized glass solar filter that fits snugly over the top end of the tube. A welder’s glass gives a green solar image, mylar a blue one and black polymer a pale orange. Filters work by only allowing a fraction of the Sun’s light to reach the eye. At the end of this article I’ve listed several sites that sell a variety of safe solar filters for naked eye and telescopic use.


Easy guide to building a pinhole projector for solar eclipse viewing

Indirect methods for safe viewing include projecting the Sun’s image through a small telescope or pair of binoculars onto a sheet of white paper or cardboard. You can also build a pinhole projector shown in the video above. A box and piece of aluminum foil are all you need.

Tiny gaps along the length of this palm frond created a series of solar crescents during the July 1991 eclipse. Credit: Bob King


Tiny gaps along the length of this palm frond created a series of solar crescents during the July 1991 eclipse. Credit: Bob King
If for some reason you aren’t able to get a solar filter, all is not lost. The tiny spaces between leaves on a tree act like pinhole projectors and will cast hundreds of images of the Sun on the ground below during the eclipse. To see the effect even better, bring along a white sheet or blanket and spread it out beneath the tree. You can even cross your hands over one another at a right angle to create a pattern of small “holes” that will reveal the changing shape of the Sun as the eclipse proceeds.

The white crescents show how much of the Sun will be visible from a variety of locations at maximum eclipse. The farther north you go, the deeper the eclipse. Credit: Jay Anderson


The white crescents show how much of the Sun will be visible from a variety of locations at maximum eclipse. The farther north you go, the deeper the eclipse. Credit: Jay Anderson
Now that you’re rockin’ to go, here are some other cool things to look for during the eclipse:

* Sunspots appear black when viewed through a filtered telescope, but they’re no match for the opaque-black  Moon silhouetted against the Sun. Compare their unequal degrees of darkness. With a little luck, the giant sunspot region 2192  will provide a striking contrast with the moon plus add interest to the eclipse. This region only recently rotated onto the Sun’s front side and will be squarely in view on Thursday.

* The moon may look smooth and round to the eye, but its circumference is bumpy with crater rims and mountain peaks. Watch for these tiny teeth to bite into the solar disk as the eclipse progresses.

* From locations where half or more the Sun’s disk is covered, look around to see if you can tell the light has changed. Does it seem somehow “grayer” than normal? Is the blueness of the sky affected?

As I learned from comet discoverer and author David Levy many years ago, every eclipse involves the alignment of four bodies: Sun, Earth, Moon and you. We wish you good weather and a wonderful eclipse, but if clouds show up, you can still watch it via live stream on SLOOH.

Not only will the sun be eclipsed this afternoon but the planet Venus shines just 1.1 degrees to its north. Venus is very close to superior conjunction which occurs early Saturday. In the photo, the planet is in the background well behind the Sun. Don’t count on seeing Venus – too much glare! This photo was taken from space by NASA’s Solar and Heliospheric Observatory this afternoon using a coronagraph to block the Sun from view. Credit: NASA/ESA


UPDATE: Not only will the sun be eclipsed Thursday afternoon but the planet Venus will shine just 1.1 degrees to its north. Venus is just two days from superior conjunction. In the photo, the planet is in the background well behind the Sun. Don’t count on seeing it – too close and too much dangerous glare! This photo was taken from space by NASA’s Solar and Heliospheric Observatory early Thursday Oct. 23 using a coronagraph to shade the Sun. Credit: NASA/ESA
Solar filter suppliers – for a #14 welder’s glass, check your local phone book for a welding supply shop:

* Thousand Oaks Optical — Large variety of solar filters for telescopes and cameras. Sheets of black polymer available if you want to make your own.
* Rainbow Symphony — Eclipse glasses and solar viewers as well as filters for binoculars and telescopes. The basic glasses cost less than a buck apiece, but you’ll need to buy a minimum of 25 pairs.
* Opt Corp — Offers high-quality Baader mylar optical filter material to make your own.
* Orion Telescopes — Glass and mylar filters for telescopes and binoculars.
* Amazon.com – Filters for naked eye use



About 

I'm a long-time amateur astronomer and member of the American Association of Variable Star Observers (AAVSO). My observing passions include everything from auroras to Z Cam stars. Every day the universe offers up something both beautiful and thought-provoking. I also write a daily astronomy blog called Astro Bob.

Awesome Photo Shows Monster Sunspot Aiming Our Way

Awesome Photo Shows Monster Sunspot Aiming Our Way:

by Jason Major on October 20, 2014
Visible light image of the Sun captured on Oct. 19, 2014. © Alan Friedman. All rights reserved.


Visible light image of the Sun captured on Oct. 19, 2014. © Alan Friedman. All rights reserved.
It’s a-comin': a “monster” sunspot is steadily rotating around the Sun’s southern hemisphere and will soon be in position to fire flares and CMEs in our direction — and this past weekend master solar photographer Alan Friedman captured it on camera!

The image above was taken in full-spectrum visible light on Sunday, Oct. 19 by Alan from his backyard in Buffalo, New York. Sunspots 2186 (at the top limb), 2187 (upper center), 2193 (the small middle cluster) and the enormous AR2192 are easily visible as dark blotches – “cooler” regions on the Sun’s surface where upwelling magnetic fields interrupt the convective processes that drive the Sun’s energy output.

This particular image was a single frame of video, unlike some of Alan’s other photographs. According to Alan the air turbulence was particularly bad that day, shooting between the clouds, so only this one frame was usable. Click the image for full-scale “wow” factor.

(And if you think AR2192 looks scary in that image, check it out in CaK bands here!)

Scale size of Earth compared to AR2192 on Oct. 20 (NASA/SDO/AIA. Edit by J. Major.)


Scale size of Earth compared to AR2192 on Oct. 20 (NASA/SDO/AIA. Diagram by J. Major.)
According to Spaceweather.com AR2192 has grown considerably over the past few days and has the potential to unleash M- and X-class flares in our direction now that it’s moving into Earth-facing position. It’s currently many times larger than Earth and will likely get even bigger… in fact, during this week’s partial solar eclipse AR2192 should be visible with the naked (but not unprotected!) eye for viewers across much of North America.

See more of Alan’s photography on his Averted Imagination site here (with prints available for purchase) and watch a TEDx presentation by Alan on how and why he does solar photography.

Image © Alan Friedman. Used with permission.



About 

A graphic designer in Rhode Island, Jason writes about space exploration on his blog Lights In The Dark, Discovery News, and, of course, here on Universe Today. Ad astra!

Water On The Moon Was Blown in by Solar Wind

Water On The Moon Was Blown in by Solar Wind:

Near-infrared image of the Moon's surface by NASA's Moon Mineralogy Mapper on the Indian Space Research Organization's Chandrayaan-1 mission Image credit: ISRO/NASA/JPL-Caltech/Brown Univ./USGS


Near-infrared image of the Moon’s surface by the Indian Space Research Organization’s Chandrayaan-1 mission. Image credit: ISRO/NASA/JPL-Caltech/Brown Univ./USGS
When they first set foot on the Moon, the Apollo 11 astronauts painted a picture of the landscape as a bone-dry desert. So astronomers were naturally surprised when in 2009, three probes showed that a lot of water is locked up in minerals in the soil. There has been some debate as to where the water came from, but now two researchers with the National Museum of Natural History in Paris, France, have determined that most of the water in the soil on the surface of the Moon was formed due to protons in the solar wind colliding with oxygen in lunar dust, rather than from comet or meteorite impacts.


The first hints that there was water on the Moon came when India’s Chandrayaan-1 found hints of water across the lunar surface when it measured a dip in reflected sunlight at a wavelength absorbed only by water and hydroxyl, a molecule that contains one atom of hydrogen and one atom of oxygen.

To help clarify this picture, NASA scientists turned to data collected by two of their space probes – the Cassini probe, which buzzed the moon in 1999 on its way to Saturn, and NASA’s Deep Impact spacecraft, which flew past the moon in June 2009 en route to an encounter with the comet Hartley 2. Both spacecraft confirmed the evidence of water and hydroxyl, molecules that are likely both present on the moon.

Lunar Crater as imaged by NASA's Moon Mineralogy Mapper. Image Credit: SRO/NASA/JPL-Caltech/USGS/Brown Univ.


Lunar Crater as imaged by NASA’s Moon Mineralogy Mapper. Image Credit: SRO/NASA/JPL-Caltech/USGS/Brown Univ.
There were three likely explanations as to how that water got there. Comets and meteorites were two possibilities, while others believed it may be caused by solar wind. In the latter case, the water would have been formed by streams of plasma emanating from the sun’s upper atmosphere and smashing high-energy protons into the moon’s surface. Cosmic rays from outside the solar system could inject ions into lunar rocks as well, causing chemical changes that create water.

To find out the likeliest source of the water, Alice Stephant and Francois Robert measured the ratio of hydrogen and deuterium in soil samples from the Apollo 16 and Apollo 17 missions. They ran the samples through a type of mass spectrometer that not only detects which isotopes are present but how deep down they are in a surface sample.

In studying tiny grains of lunar soil samples, they found that the reduction of oxygen from silicates in the soil by protons from the solar wind was almost certainly the means by which the water was generated. They came to that conclusion through determining the lithium isotope ratio in the samples which gave the isotope ratio for the hydrogen. From that, they were able to calculate the deuterium-hydrogen ratio which they compared to the amount of water actually in the granule sample.

Because there tends to be more deuterium further from the sun, each possible source of lunar water should give a different ratio. Comets and meteorites have distinctive proportions, while protons from the solar wind or cosmic rays would each have different ratios.

What they found was that on average, the granules contained just 15 percent water from somewhere else (presumably comets or meteorites) leaving the rest to have been formed due to the solar wind interaction. They note also that for some samples, all of the water was due to solar wind interaction.

“We confirm that result,” said Stephant. “Water-rich meteorite and comet impacts do not bring important amounts of water to the surface of the moon.”

Alberto Saal at Brown University in Providence, Rhode Island, is pleased with the result. “I think the idea that most of the water in the surface of the moon comes from solar wind implantations is most likely correct,” he says.

In their paper published in Proceedings of the National Academy of Sciences, Alice Stephant and François Robert describe their study and the results they found. However, they were also quick to point out that their conclusions only relate to water found on the surface of the moon – whereas the origin of the water below the surface is still open to interpretation.

Further reading: PNAS



About 

Author, freelance writer, educator, Taekwon-Do instructor, and loving hubby, son and Island boy!

MRO Spies Tiny, Bright Nucleus During Comet Flyby

MRO Spies Tiny, Bright Nucleus During Comet Flyby:

High resolution image pairs made with HiRISE camera on MRO during Comet Siding Spring's closest approach to Mars on October 19. Shown at top are images of the nucleus region and inner coma. Those at bottom were exposed to show the bigger coma beginning of a tail. Credit: NASA/JPL/Univ. of Arizona


High resolution image pairs made with HiRISE camera on MRO during Comet Siding Spring’s closest approach to Mars on October 19. Shown at top are images of the nucleus region and inner coma. Those at bottom were exposed to show the bigger coma and the beginning of a tail. Credit: NASA/JPL/Univ. of Arizona
Not to be outdone by the feisty Opportunity Rover, the HiRISE camera on NASA’s Mars Reconnaissance Orbiter (MRO) turned in its homework this evening with a fine image of comet C/2013 Siding Spring taken during closest approach on October 19.

The highest-resolution images were acquired by HiRISE at the minimum distance of 85,750 miles (138,000 km). The image has a scale of 453 feet (138-m) per pixel.

The top set of photos uses the full dynamic range of the camera to accurately depict brightness and detail in the nuclear region and inner coma. Prior to its arrival near Mars astronomers estimated the nucleus or comet’s core diameter at around 0.6 mile (1 km). Based on these images, where the brightest feature is only 2-3 pixels across, its true size is shy of 1/3 mile or 0.5 km. The bottom photos overexpose the comet’s innards but reveal an extended coma and the beginning of a tail extending to the right.

Annotated photo of Comet Siding Spring taken by the Opportunity Rover on October 19 when near closest approach. Credit: NASA/JPL-Caltech/Cornell Univ./ASU/TAMU


Annotated photo of Comet Siding Spring taken by the Opportunity Rover on October 19 when near closest approach. Credit: NASA/JPL-Caltech/Cornell Univ./ASU/TAMU
To photograph a fast-moving target from orbit, engineers at Lockheed-Martin in Denver precisely pointed and slewed the spacecraft based on comet position calculations by engineers at JPL. To make sure they knew exactly where the comet was, the team photographed the comet 12 days in advance when it was barely bright enough to register above the detector’s noise level. To their surprise, it was not exactly where orbital calculations had predicted it to be. Using the new positions, MRO succeeded in locking onto the comet during the flyby. Without this “double check” its cameras may have missed seeing Siding Spring altogether!

Meanwhile, the Jet Propulsion Lab has released an annotated image showing the stars around the comet in the photo taken by NASA’s Opportunity Rover during closest approach. From Mars’ perspective the comet passed near Alpha Ceti in the constellation Cetus, but here on Earth we see it in southern Ophiuchus not far from Sagittarius.

Comet Siding Spring continues on its way today past the planet Mars in this photo taken on October 20. Copyright: Rolando Ligustri


Comet Siding Spring continues on its way today past the planet Mars in this photo taken on October 20. Copyright: Rolando Ligustri
“It’s excitingly fortunate that this comet came so close to Mars to give us a chance to study it with the instruments we’re using to study Mars,” said Opportunity science team member Mark Lemmon of Texas A&M University, who coordinated the camera pointing. “The views from Mars rovers, in particular, give us a human perspective, because they are about as sensitive to light as our eyes would be.”

After seeing photos from both Earth and Mars I swear I’m that close to picturing this comet in 3D in my mind’s eye. NASA engineers and scientists deserve a huge thanks for their amazing and successful effort to turn rovers and spacecraft, intended for other purposes, into comet observatories in a pinch and then deliver results within 24 hours. Nice work!



About 

I'm a long-time amateur astronomer and member of the American Association of Variable Star Observers (AAVSO). My observing passions include everything from auroras to Z Cam stars. Every day the universe offers up something both beautiful and thought-provoking. I also write a daily astronomy blog called Astro Bob.

How to Take Great Photographs of the October 23rd Partial Solar Eclipse and More

How to Take Great Photographs of the October 23rd Partial Solar Eclipse and More:

The Partially eclipsed Sun rising over the Vehicle Assembly Building on the Florida Space Coast on November 3rd, 2013.


The partially eclipsed Sun rising over the Vehicle Assembly Building on the Florida Space Coast on November 3rd, 2013. Photo by author.
Get those solar viewers out… the final eclipse of 2014 occurs this Thursday on October 23rd, and most of North America has a front row seat. Though this solar eclipse will be an exclusively partial one as the Moon takes a ‘bite’ out the disk of the Sun, such an event is always fascinating to witness. And for viewers across the central U.S. and Canada, it will also provide the chance to photograph the setting crescent Sun along with foreground objects.

Michael Zieler


A map showing the eclipse prospects over the CONUS. (click to enlarge). Credit: Michael Zeiler @EclipseMaps, www.thegreatamericaneclipse.com.
The shadow or ‘antumbra’ of the Moon just misses northern limb of the Earth on October 23rd, resulting in a solar eclipse that reaches a maximum of 81% partial as seen from the high Canadian Arctic. The eclipse would be annular in any event had the Moon’s shadow touched down on Earth’s surface, as the Moon just passed apogee on October 18th. The penumbral cone of the Moon’s shadow touches down at 19:38 UT in the Bering Sea just west of the International Date Line before racing eastward across North America to depart the Earth over southern Texas at 23:52 UT.

NASA/GSFC


An animated .gif of this week’s partial solar eclipse.  Credit: NASA/GSFC/A.T. Sinclair.
The farther northwest you are, the greater the eclipse: For example, Anchorage and Seattle will see 54.8% and 54.5% of the Sun obscured by the Moon, while Mexico City and Phoenix, Arizona will see 4.8% and 33% of the Sun’s disk obscured.

A key region will be the zone of longitude running a few hundred miles east and to the west of Ontario, the Great Lakes and the Mississippi River, which will see the Sun setting during greatest eclipse.

Stellarium


Simulated views of the October 23rd partial solar eclipse from around North America. Created using Stellarium.
Successful sunset viewing of the eclipse will call for a clear, uncluttered western horizon. As of 48+ hours out, the current weather prospects call for clear skies across most of the U.S. on Thursday, with the exception of the U.S. northwest… but you only need a gap in the clouds to observe an eclipse!

NOAA


Predicted cloud cover for the CONUS hours prior to the start of the Oct 23 partial solar eclipse. Credit: NWS/NOAA.
It’s also worth noting that massive sunspot region AR 2192 is currently turned Earthward and will make for a very active and photogenic Sun during Thursday’s eclipse.

SDO/HMI


Sunspot activity leading up to this week’s eclipse. Credit: NASA/SDO/HMI
Proper safety precautions must be taken while observing the Sun through all stages of a partial solar eclipse. Don’t end up like 19th century psychologist Gustav Fechner, who blinded himself staring at the Sun! With the recent interest in the event, we’ve been fielding lots of questions on eclipse imaging, which presents safety challenges of its own.

blogger-image-845084267


An homemade solar optical filter using Baader film. Credit: Eric Teske/Stellar Neophyte.
Imaging the Sun with a solar filter is pretty straightforward. Glass solar filters for telescopes fitting over the full aperture of the instrument can be had from Orion for about $100 USD, and we’ve made inexpensive filter masks out of Baader AstroSolar Safety Film for everything from binoculars to DLSR cameras to telescopes. Make sure these fit snugly in place, and inspect them for pin holes prior to use. Also, be sure to cover or remove any finderscopes as well. And throw away those old screw-on eyepiece filters sold by some department store scope manufacturers in the 60s and 70s, as they can overheat and crack!

Catching the eclipsed Sun with a silhouetted foreground requires more practice. We’ve had great luck using a DSLR and a neutral density filter to take the f-stop and glare down while preserving the foreground view. Remember, though, an ND filter is for photographic use only… never stare at the Sun through one! Likewise, you’ll need to physically block off your camera’s viewfinder to resist the same temptation of looking while aiming. Shooting several quick frames at 1/1000th of a second or faster will help get the ISO/f-stop settings for the local illumination just right. Even 1% sunlight is surprisingly bright, as we noticed observing the May 10th 1994 annular eclipse from the shores of Lake Erie.

You’ll also need a lens with a focal length of 200mm or better to have the Sun appear larger than a dot in your images. Several key landmarks, such as the Saint Louis Arch and the Sears Tower in Chicago lie along the key sunset zone Thursday and  would make great potential foreground shots… our top pick would be the 1978 World’s Fair Sunsphere Tower in Knoxville, Tennessee for a photo with a true visual double entendre. Scout out the geometry of such a shot the evening beforehand, and remember that you’ll need a good amount of distance (half a mile or more) for a building or foreground object to appear equal in size to the Sun.

And don’t miss the spectacle going on around you during an eclipse as well. Projecting the disk of the Sun using a pinhole camera or binoculars onto a piece of paper makes for a great shot. Hundreds of crescents may litter the ground, caused by natural “pinhole projectors” such as gaps in leaves or latticework. And photographs of everyday folks wearing eclipse glasses standing enthralled by the ongoing event can be just as captivating as the eclipse itself.

Photo by author


Imaging a partial solar eclipse via a homemade shoebox binocular projector. Photo by author.
Up for a challenge? Another unique opportunity awaits eclipse viewers in the northwest, as the International Space Station will cross the disk of the Sun around ~21:08 UT during the eclipse. You’ll need to run video to catch such a speedy (about a second in duration) event, but it would make for a great capture! Be sure to check CALSky for predictions of ISS solar and lunar transits within 48 hours of the event.

ISS path


The path of the ISS over the US during the partial eclipse. Credit: Orbitron.
Robotic eyes in low Earth orbit will be watching the eclipse as well. JAXA’s Hinode and ESA’s Proba-2 routinely observe the Sun and will catch fleeting eclipses on successive passes on Thursday… in the case of Hinode, it may score a direct “hit” with an annular eclipse seen from space around 21:03 UT:



And don’t forget, we’re now less than three years out from the next total solar eclipse to (finally!) grace the United States from coast to coast on August 21st, 2017. This week’s partial solar eclipse offers a great test run to hone your photographic technique!

-Send those eclipse pics in to Universe Today’s Flickr forum.



About 

David Dickinson is an Earth science teacher, freelance science writer, retired USAF veteran & backyard astronomer. He currently writes and ponders the universe from Tampa Bay, Florida.

Could ‘Heavy Metal’ Frost Lurk Beneath Venus’ Hothouse Clouds?

Could ‘Heavy Metal’ Frost Lurk Beneath Venus’ Hothouse Clouds?:

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
Talk about using old data for a new purpose! Researchers re-examining information from the completed NASA Magellan mission found signs of what could be “heavy metal” frost on the hell-like surface. What the researchers saw in radio-wave reflectance is the highlands appear brighter, with dark spots in the tallest locations.

What substance exactly is causing the patches on the surface is unknown, and it is extremely hard to make predictions given the difficulty of simulating Venus’ 900-degree Fahrenheit (500-degree Celsius) surface temperature, which is also 90 times Earth’s air pressure at sea level.

“Like on Earth, the temperature changes with elevation,” stated Elise Harrington, an Earth sciences undergraduate at British Columbia’s Simon Fraser University who led the research. “Among the possibilities on Venus are a temperature dependent chemical-weathering process or heavy metal compound precipitating from the air – a heavy metal frost.”

Venus' volcano Sapas Mons, which was imaged by the Magellan mission in 1991. Credit: NASA


Venus’ volcano Sapas Mons, which was imaged by the Magellan mission in 1991. Credit: NASA
Scrutiny of a previously examined area on Venus, the Odva Regio highlands, saw a low radar reflection at 2,400 meters (7,900 feet), which progressively gets brighter until dark spots begin appearing and reflections drop at 4,700 meters (15,400 meters).

While previous research spotted a few of these patches, Harrington and supervisor Allan Treiman (Lunar and Planetary Institute) saw hundreds. There’s no radar-imaging spacecraft in orbit around Venus right now, but the authors hope that the finding will generate more interest in this planet. (Of note, the European Space Agency’s Venus Express is finishing up a mission there now, which included several daring atmosphere-skimming maneuvers earlier this year.)

The research was presented at the Geological Society of America meeting in Vancouver, British Columbia.

Source: Geological Society of America



About 

Elizabeth Howell is the senior writer at Universe Today. She also works for Space.com, Space Exploration Network, the NASA Lunar Science Institute, NASA Astrobiology Magazine and LiveScience, among others. Career highlights include watching three shuttle launches, and going on a two-week simulated Mars expedition in rural Utah. You can follow her on Twitter @howellspace or contact her at her website.

How NASA and SpaceX are Working Together to Land on Mars

How NASA and SpaceX are Working Together to Land on Mars:

Thermal imagery of Falcon 9 rocket. Image Credit: NASA/Scifli Team/Applied Physics Laboratory Images


Thermal imagery of Falcon 9 rocket. Image Credit: NASA/Scifli Team/Applied Physics Laboratory Images
It is no secret that NASA is seeking out private space contractors to help bring some of its current plans to fruition. Naturally, these involve restoring indigenous launch capabilities to the US, but also include the more far-reaching goal of sending astronauts to Mars. Towards that end, NASA and SpaceX participated in an unprecedented data-sharing project that will benefit them both.

The project took place on Sept. 21st when, after multiple attempts, NASA and the U.S. Navy used a series of IR tracking cameras to capture footage of one of SpaceX’s Falcon 9 reusable rockets in flight. The cameras recorded the rocket as the second stage engine ignited and the first stage,  having detached and fallen away, reignited its engines to lower itself  back to Earth for a zero-g touchdown on the sea surface.

The resulting data is being shared between the two parties and will benefit them both.

For SpaceX, the benefit comes in the form of the detailed information NASA is providing on temperatures and aerodynamic loading on the Falcon 9 rocket, which will help them in their efforts to develop a reusable rocket system. For NASA, engineers are getting a chance to collect data on supersonic retro-propulsion that may one day help them to lower massive, multi-ton payloads onto the surface of Mars.

“Because the technologies required to land large payloads on Mars are significantly different than those used here on Earth, investment in these technologies is critical,” said Robert Braun, principal investigator for NASA’s Propulsive Descent Technologies (PDT) project and professor at the Georgia Institute of Technology in Atlanta. He’s also NASA former Chief Technologist. “This is the first high-fidelity data set of a rocket system firing into its direction of travel while traveling at supersonic speeds in Mars-relevant conditions. Analysis of this unique data set will enable system engineers to extract important lessons for the application and infusion of supersonic retro-propulsion into future NASA missions.”

Supersonic retro-propulsion basically means generating supersonic thrust to shed velocity after atmospheric entry. Alongside aerobraking, this is one of the proposed means of landing heavy equipment and habitats on Mars.

Braun is certainly no stranger to the concept. After returning to Georgia Tech, Braun – a specialist in entry, descent and landing (EDL) – worked with engineers from the university and various NASA centers to develop a proposal for a program to flight-test this concept.

At the time, NASA’s Space Technology Mission Directorate (STMD) rejected the plan for being too expensive, but the agency still needs a way to land payloads in excess of 20 tons if ever it wants to mount a human expedition to Mars. And given that the proposed mission is due to take place within the next 16 years, the more information they obtain now, the better.

In Depth: The Mars Landing Approach: The Problems of Landing Large Payloads on the Surface of Mars

Hence the decision to partner with SpaceX. Basically, the PDT Project struck a deal to use airborne infrared-imaging techniques – developed to study the Space Shuttle in flight after the Columbia accident – to gather data on the supersonic retro-propulsion SpaceX is currently using for its reusable launch vehicle development.

This sort of collaboration is without precedent, and as Braun told Universe Today via email, stands to benefit both participants immensely:

“This is the first high-fidelity data set of a rocket system firing into its direction of travel while traveling at supersonic speeds in Mars-relevant conditions. The synergy between NASA’s interest in improving its Mars entry, descent and landing capability and Space X’s interest and experimental operation of a reusable space transportation system provided a unique opportunity to obtain this data at low cost. Analysis of this unique data set will enable system engineers to extract important lessons for the infusion of supersonic retropropulsion into future NASA missions that may one day lower large payloads to the Mars surface while providing SpaceX with engineering insight to advance its development of a reusable space transportation system.”
After unsuccessful attempts to image the rocket on two previous missions – April 18 and July 14 – the project succeeded with the CRS-4 flight on Sept. 21st. Launched at night, NASA relied on two aircraft –  a WB-57 and a NP-3D Orion – equipped with mid-wave IR sensors to document re-entry of the rocket’s first stage.

The first stage is the part of the rocket that is ignited at launch and burns through the rocket’s ascent until it runs out of propellant, at which point it is discarded from the second stage and returns to Earth. It was during its return, or descent, that NASA captured quality infrared and high definition images and monitored changes in the smoke plume as the engines were turned on and off.

Watch the video of the footage:



For NASA, the period of the flight most relevant for future operations over Mars came when the first stage was traveling at about Mach 2 some 30,000 – 45,000 meters (100,000-150,000 ft.) above the surface. The two midwave IR sensors – mounted in a nose pod on the WB-57 and internally on the NP-3D – were about 60 nautical miles from the rocket when it reignited its engines for supersonic retro-propulsion.

That produced raw images in which the stage appeared 1 pixel wide and 10 pixels long, but subsequent enhancing by specialists at the Johns Hopkins University Applied Physics Laboratory improved the resolution dramatically.

“NASA’s interest in building our Mars entry, descent and landing capability and SpaceX’s interest and experimental operation of a reusable space transportation system enabled acquisition of these data at low cost, without standing up a dedicated flight project of its own,” said Charles Campbell, PDT project manager at NASA’s Johnson Space Center in Houston.

Engineers at NASA and SpaceX are now correlating that data with company telemetry from the Sept. 21st Falcon 9 launch of a Dragon cargo carrier to the International Space Station to learn exactly what the vehicle was doing in terms of engine-firing and maneuvering when it generated the signatures collected by the aircraft.

Further Reading: NASA



About 

Author, freelance writer, educator, Taekwon-Do instructor, and loving hubby, son and Island boy!