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November 1, 2016November 3, 2016 by Matt Williams

Curiosity Finds a Melted Space Metal Meteorite on the Surface of Mars

Image from Curiosity's Mast Camera (Mastcam), which captured a small rock believed to be a meteorite on Sol 153. Credit: NASA/JPL-Caltech/LANL/ASU

Since it landed on the surface of the Red Planet in 2012, the Curiosity rover has made some rather surprising finds. In the past, this has included evidence that liquid water once filled the Gale Crater, the presence of methane and organic molecules today, curious sedimentary formations, and even a strange ball-shaped rock.

And most recently, Curiosity’s Mast Camera (Mastcam) captured images of what appeared to be a ball of melted metal. Known as “Egg Rock” (due to its odd, ovoid appearance) this object has been identified as a small meteorites, most likely composed of nickel and iron.

Egg Rock was first noticed in an image that was snapped by Curiosity on Oct. 28th, 2016, (or Sol 153, the 153rd day of Curiosity’s mission). The rover then snapped a two-frame portrait of the meteorite (seen below) two days later (on Sol 155) and studied it using its ChemCam’s Remote Micro-Imager (RMI). This provided not only a close-up of the strange object, but also a chance for chemical analysis.

Close up of Egg Rock, showing the laser reflection from Curiosity's ChemCam. Credit: NASA/JPL — *Close up of “Egg Rock”, showing the laser reflections from Curiosity’s ChemCam instrument. Credit: NASA/JPL*

The chemical analysis revealed that the rock was composed of metal, which explained its melted appearance. In essence, it is likely the rock became molten as it entered Mars’ atmosphere, leading to the metal softening and flowing. Once it reached the surface, it cooled to the point that this appearance became frozen on its face.

Such a find is quite exciting, if not entirely unexpected. In the past, Curiosity and other rovers has spotted the remains of other metallic meteorites. For instance, back in 2005, the Opportunity rover spotted a pitted, basketball-sized iron meteorite that was named “Heat Shield Rock“.

This was followed in 2009 by the discovery of “Block Island“, a large dark rock that measured 0.6 meters (2 feet) across and contained large traces of iron. And in 2014, Curiosity spotted the mostly-iron meteorite that came to be known as “Lebanon” which measured 2 meters (6.5 feet) wide – making it the largest meteorite to ever be found on Mars.

However, “Egg Rock” is somewhat unique, in that its appearance seems more “melted” than meteorites spotted in the past. And as George Dvorsky of Gizmodo indicated, other aspects of its appearance (such as the long hollows) could mean that it lost material, perhaps when it still molten (i.e. shortly after it reached the surface).

Iron Meteorite on Mars. Opportunity finds an iron meteorite on Mars, the first meteorite of any type ever identified on another planet. The pitted, basketball-size object is mostly made of iron and nickel. Opportunity used its panoramic camera to take the images used in this approximately true-color composite on the Sol 339 (Jan. 6, 2005). Credit: NASA/JPL/Cornell — *Image of the iron meteorite fpund on Mars by the Opportunity rover on the Sol 339 (Jan. 6th, 2005). Credit: NASA/JPL/Cornell*

And such finds are always interesting because they provide us with the opportunity to study chunks of the Solar System that might not survive the trip to Earth. Given its greater proximity to the Asteroid Belt, Mars is better situated to be periodically struck by objects that get kicked out of it by Jupiter’s gravity. In fact, it is theorized that this is how Mars got its moons, Phobos and Deimos.

In addition, meteorites are more likely to survive passing through Mars’ atmosphere, since it is only about 1% as dense as Earth’s. Last, but certainly not least, meteorites have been striking Earth and Mars for eons. But since Mars has had a dry, desiccated atmosphere for all of that time, meteorites that land on its surface are subject to less wind and water erosion.

As such, Martian meteorites are more likely to be intact and better preserved over the long haul. And studying them will give planetary scientists opportunities they may not enjoy here on Earth. Now if we could just transport some of these space rocks home for a more detailed analysis, we’d be in business! Perhaps that should be something for future missions to consider.

Further Reading: ASU – Red Planet Report

November 1, 2016November 2, 2016 by Matt Williams

Even Though it’s an Alien World, Titan’s Canyons Would Look Very Familiar

In this near-infrared mosaic, the sun shines off of the seas on Saturn's moon, Titan. Credit: NASA/JPL-Caltech/University of Arizona/University of Idaho

Titan is tough moon to study, thanks to its incredibly thick and hazy atmosphere. But when astronomers have ben able to sneak a peak beneath its methane clouds, they have spotted some very intriguing features. And some of these, interestingly enough, are reminiscent of geographical features here on Earth. For instance, Titan is the only other body in the Solar System that is known to have a cycle where liquid is exchanged between the surface and the atmosphere.

For example, previous images provided by NASA’s Cassini mission showed indications of steep-sided canyons in the northern polar region that appeared to be filled with liquid hydrocarbons, similar to river valleys here on Earth. And thanks to new data obtained through radar altimetry, these canyons have been shown to be hundreds of meters deep, and have confirmed rivers of liquid methane flowing through them.

This evidence was presented in a new study titled “Liquid-filled canyons on Titan” – which was published in August of 2016 in the journal Geophysical Research Letters. Using data obtained by the Cassini radar altimeter in May 2013, they observed channels in the feature known as Vid Flumina, a drainage network connected to Titan’s second largest hydrocarbon sea in the north, Ligeia Mare.

Saturn's largest moon, Titan, has features that resemble Earth's geology, with deep, steep-sided canyons. Credit: NASA/JPL/Cassini — *Saturn’s largest moon, Titan, has features that resemble Earth’s geology, with deep, steep-sided canyons. Credit: NASA/JPL/Cassini*

Analysis of this information showed that the channels in this region are steep-sided and measure about 800 m (half a mile) wide and between 244 and 579 meters deep (800 – 1900 feet). The radar echoes also showed strong surface reflections that indicated that these channels are currently filled with liquid. The elevation of this liquid was also consistent with that of Ligeia Mare (within a maring of 0.7 m), which averages about 50 m (164 ft) deep.

This is consistent with the belief that these river channels in area drain into the Ligeia Mare, which is especially interesting since it parallels how deep-canyon river systems empty into lakes here on Earth. And it is yet another example of how the methane-based hydrological cycle on Titan drives the formation and evolution of the moon’s features, and in ways that are strikingly similar to the water cycle here on Earth.

Alex Hayes – an assistant professor of astronomy at Cornell, the Director of the Spacecraft Planetary Imaging Facility (SPIF) and one of the authors on the paper – has conducted seversal studies of Titan’s surface and atmosphere based on radar data provided by Cassini. As he was quoted as saying in a recent article by the Cornell Chronicler:

“Earth is warm and rocky, with rivers of water, while Titan is cold and icy, with rivers of methane. And yet it’s remarkable that we find such similar features on both worlds. The canyons found in Titan’s north are even more surprising, as we have no idea how they formed. Their narrow width and depth imply rapid erosion, as sea levels rise and fall in the nearby sea. This brings up a host of questions, such as where did all the eroded material go?”

The northern polar area of Titan and Vid Flumina drainage basin. (left) On top of the image, the Ligeia Mare; in the lower right the North Kraken Mare; the two seas are connected each other by a labyrinth of channels. On the left, near the North pole, the Punga Mare. Red arrows indicate the position of the two flumina significant for this work. At the end of its mission (15 September 2017) the Cassini RADAR in its imaging mode (SAR+ HiSAR) will have covered a total area of 67% of the surface of Titan [Hayes, 2016]. Map credits: R. L. Kirk. (right) Highlighted in yellow are the half-power altimetric footprints within the Vid Flumina drainage basin and the Xanthus Flumen course for which specular reflections occurred. At 1400?km of spacecraft altitude, the Cassini antenna 0.35° central beam produces footprints of about 8.5?km in diameter (diameter of yellow circles). Credit: NASA/JPL — *Cassini image of the northern polar area of Titan and Vid Flumina drainage basin, showing Ligeia Mare (left) and the Vid Flumina drainage basin (right). Credit: R.L. Kirk/NASA/JPL*

A good question indeed, since it raises some interesting possibilities. Essentially, the features observed by Cassini are just part of Titan’s northern polar region, which is covered by large standing bodies of liquid methane – the largest of these being Kraken Mare, Ligeia Mare and Punga Mare. In this respect, the region is similar to glacially eroded fjords on Earth.

However, conditions on Titan do not allow for the presence of glaciers, which rules out the likelihood that retreating sheets of ice could have carved these canyons. So this naturally begs the question, what geological forces created this region? The team concluded that there were only two likely possibilities – which included changes in the elevation of the rivers, or tectonic activity in the area.

Ultimately, they favored a model where the variation in surface elevation of liquid drove the formation of the canyons – though they acknowledge that both tectonic forces and sea level variations played a role. As Valerio Poggiali, an associate member of the Cassini RADAR Science Team at the Sapienza University of Rome and the lead author of the paper, told Universe Today via email:

“What the canyons on Titan really mean is that in the past sea level was lower and so erosion and canyon formation could take place. Subsequently sea level has risen and backfilled the canyons. This presumably takes place over multiple cycles, eroding when sea level is lower, depositing some when it is higher until we get the canyons we see today. So, what it means is that sea level has likely changed in the geological past and the canyons are recording that change for us.”

Titan's Ligeia Mare. Credit: NASA/JPL/USGS — *Titan’s second largest methane lake, Ligeia Mare. Credit: NASA/JPL/USGS*

In this respect, there are many more Earth examples to choose from, all of which are mentioned in the study:

“Examples include Lake Powell, a reservoir on the Colorado River that was created by the Glen Canyon Dam; the Georges River in New South Wales, Australia; and the Nile River gorge, which formed as the Mediterranean Sea dried up during the late Miocene. Rising liquid levels in the geologically recent past led to the flooding of these valleys, with morphologies similar to those observed at Vid Flumina.”

Understanding the processes that led to these formations is crucial to understanding the current state of Titan’s geomorphology. And this study is significant in that it is the first to conclude that the rivers in the Vid Flumina region were deep canyons. In the future, the research team hopes to examine other channels on Titan that were observed by Cassini to test their theories.

Once again, our exploration of the Solar System has shown us just how weird and wonderful it truly is. In addition to all its celestial bodies having their own particular quirks, they still have a lot in common with Earth. By the time the Cassini mission is complete (Sept. 15th, 2017), it will have surveyed 67% the surface of Titan with its RADAR imaging instrument. Who knows what other “Earth-like” features it will notice before then?

Further Reading: Geophysical Research Letters

November 1, 2016November 4, 2016 by Bob King

November Opens with a Splendid Gathering of Moon and Planets

Crescent Moon and flag. Credit: Bob King

Look how pretty. This will be the scene from your yard, apartment window or driving west along the freeway Tuesday evening about 45 minutes after sundown. Saturn and the Moon will be in conjunction about 3 degrees apart with Venus 6 degrees to the southeast of the crescent. Source: Stellarium — Look how pretty. This will be the scene from your yard, apartment window or driving west along a freeway Tuesday evening about 45 minutes after sundown. Saturn and the Moon will be in conjunction about 3 degrees apart with Venus 6 degrees to the southeast of the crescent. Source: Stellarium

I love easy and bright. While I often spend time seeking faint nebulae and wandering comets, there’s nothing like just looking up and seeing a beautiful scene aglow in the night sky. No binoculars or telescope needed. That’s exactly what will happen Tuesday November 2, when an attractive crescent Moon will join Saturn and Venus at dusk in the southwestern sky.

The supermoon of March 19, 2011 (right), compared to an average moon of December 20, 2010 (left). Note the size difference. Image Credit: Marco Langbroek, the Netherlands, via Wikimedia Commons. — The Supermoon of March 19, 2011 (right), compared to an average moon of December 20, 2010 (left). November’s Supermoon will be 14% bigger and 30% brighter than a regular Full Moon. Credit: Marco Langbroek / Wikimedia Commons

What a fine threesome they’ll make: Venus the white-hot spark shining at magnitude –4.0; Saturn a mellow magnitude +0.5, some 20 times fainter and the Moon a fingernail crescent above them both. The Moon will be just two days past apogee, the furthest point in its orbit from Earth. Does it look a little smaller than the usual crescent? If you’re a keen watcher of crescents, you just might notice the difference.

In less than two weeks, on November 14, the crescent will have waxed to full, swung around to the opposite end of its orbit, where it will be at perigee, its closest point to Earth. When a Full Moon occurs at perigee, we call it a Supermoon because it’s closer and correspondingly bigger and brighter than a typical Full Moon.

For a variety of reasons, the November Supermoon will come exceptionally close to Earth, the closest one in 70 years as a matter of fact. The last time Earth and Moon embraced each other so tightly was January 26, 1948, the year baseball great Babe Ruth died. But I’m getting ahead of myself. We’ll have much more on the Supermoon soon!

This photo shows the contrast between the bright, sunlit crescent and the ghostly earth-lit Moon. Several prominent craters are identified. Credit: Bob King

Tuesday night you have the pleasure of an eye-catching crescent filled with darkly luminous earthshine, sunlight reflected off our jolly blue and white globe into space that reflects from the Moon and back to Earth. Being twice reflected, the returning light is feeble, giving the Moon a haunted look.

The phases of the Moon and Earth are complementary; when one's a crescent, the other's nearly full. Credit: Bob King, Source: Stellarium — The phases of the Moon and Earth are complementary; when one’s a crescent, the other’s nearly full. Credit: Bob King, Source: Stellarium

Crescent phase is when earthshine is brightest. Why? Phases of Earth and Moon are complementary — when we see a crescent, an astronaut on the Moon would look back to see a nearly Full Earth in the sky. As you’ve already guessed, a Full Earth reflects a great deal more light than a half or crescent. Be sure to point your binoculars at the earth-lit Moon; the contrast of dusky earthlight adjacent to the sunlit crescent gives the scene a striking 3D look.

And if your glass can magnify ten times or more, you’ll get a sneak preview of several of the dark lunar seas or maria in the smoky light. Seas that will by and by ease into sunlight as the lunar terminator, the line separating day from night, rolls ever westward.

Through a small telescope, Venus appears three-quarters full in waning gibbous phase. Saturn's rings are still tipped wide open, and it's brightest moon, Titan, should be easy to spot Tuesday night in a small telescope. Source: Stellarium — Through a small telescope, Venus appears three-quarters full in waning gibbous phase. Saturn’s rings are still tipped wide open, and its brightest moon, Titan, should be easy to spot Tuesday night in a small telescope. Appearances are shown for Nov. 2. North is up and west to the right. Source: Stellarium

Have a small telescope? This may be one of your last easy chances at seeing the planet Saturn before it’s gobbled up by the western horizon. The ringed one has been sinking westward the past couple months and will soon be in conjunction with the Sun. I hate to see a good planet go, that’s why I’m happy to share that Venus will be with us a long, long time. Watch for this most brilliant of planets to rise higher in the southwestern sky as we approach Christmas and then swing to the north through early winter before dropping out of the evening sky in March 2017.

Thank you Venus for lighting our path on the snowy nights that lie ahead!

*** If you’d like learn more about how to find the planets, check out my new book, Night Sky with the Naked Eye. It covers all the wonderful things you can see in the night sky without special equipment. The book publishes on Nov. 8, but you can pre-order it right now at these online stores. Just click an icon to go to the site of your choice – Amazon, Barnes & Noble or Indiebound. It’s currently available at the first two outlets for a very nice discount:

October 31, 2016 by Nancy Atkinson

Here’s What Happens When NASA Engineers Carve Their Pumpkins

The 6th annual pumpkin carving at the Jet Propulsion Laboratory included this 'Mars sample return pumpkin.' Credit: JPL.

Every workplace should have this much fun! A group of engineers at the Jet Propulsion Laboratory held their sixth annual pumpkin carving contest, and this year’s entries did not disappoint. Using a combination of engineering savvy and creative license, the JPL engineers carved up several different types of themed pumpkins, including a cow abduction by aliens, a geyser-spewing Europa, unique depictions of several different space missions and much more.

Halloween is actually a special holiday at JPL because October 31, 1936 was the beginning of JPL’s history, when several grad students studying at Caltech and some amateur rocket enthusiasts drove out to a dry canyon tested out a liquid rocket engine. To celebrate JPL’s 80th anniversiary, here’s a link to a gallery of images pairs that shows vintage views from JPL’s history with images that show what the lab looks like today.

In addition, JPL held a Halloween costume contest that really was out of this world. See all the fun below:

This pumpkin was turned into a spooky alien abduction scene:

A pale pumpkin Europa, complete with geysers. Behind it, Juno orbits Jupiter.

Wheee! A Halloween carnival:

JPL’s Starshade was turned into a chainsaw massacre.

Need last minute ?pumpkin? carving tips? Check out what some of our employees came up with this year. Full gallery: https://t.co/jzPuMyIE1G pic.twitter.com/6eTtXsQmc2

— NASA JPL (@NASAJPL) October 28, 2016

The pictures of the costume contest are courtesy JPL mechanical engineer Aaron Yazzie’s Twitter feed:

1st Place Winner: Mars Attacker! #NASACostume pic.twitter.com/0sqhI4kKpc

— Aaron Yazzie (@YazzieSays) October 31, 2016

2nd Place Winner: NASA Mission Hats! (Including the one and only @PlanetaryKeri !) #NASACostume pic.twitter.com/zutOi4W6sd

— Aaron Yazzie (@YazzieSays) October 31, 2016

3rd place winner: Meteor Shower! #NASACostume pic.twitter.com/u4PnMQ9XVk

— Aaron Yazzie (@YazzieSays) October 31, 2016

October 31, 2016November 21, 2016 by Tammy Plotner

Messier 25 – The IC 4725 Open Cluster

Messier 25, shown in proximity to the Sagittarius Constellation. Credit: Wikisky

Welcome back to Messier Monday! In our ongoing tribute to the great Tammy Plotner, we take a look at the Messier 25 open star cluster. Enjoy!

Back in the 18th century, famed French astronomer Charles Messier noted the presence of several “nebulous objects” in the night sky. Having originally mistaken them for comets, he began compiling a list of these objects so that other astronomers wouldn’t make the same mistake. Consisting of 100 objects, the Messier Catalog has come to be viewed as a major milestone in the study of Deep Space Objects.

One of these objects is Messier 25, an open star cluster located in the direction of the Sagittarius Constellation. At a distance of about 2000 light years from Earth, it is one of the few Messier Objects that is visible to the naked eye (on a clear night when light conditions are favorable).

Description:

This galactic star cluster was originally discovered by Philippe Loys de Cheseaux in 1745 and included in Charles Messier’s catalog in 1764. Oddly enough, it was one of those curious objects that didn’t get cataloged by Sir John Herschel – therefore it never received a New General Catalog (NGC) number.

This is odd, considering that it was part of the 1777 catalog of Johann Elert Bode, observed by William Herschel in 1783, written about by Admiral Smyth in 1836 and even commented on by the Reverend Thomas William Webb in 1859! It was until J.L.E. Dreyer in 1908 that poor little M25 ended up getting added to the second Index Catalog.

Messier 25. Atlas Image mosaic obtained as part of the Two Micron All Sky Survey (2MASS), a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation. — *Atlas Image mosaic of Messier 25,obtained as part of the Two Micron All Sky Survey (2MASS). Credit: Univ. of Mass./IPAC/Caltech/NASA/NSF*

Cruising along peacefully about 2,000 light-years away from Earth, this little group of stars spans across about 19 light years of space. Caught inside of its influence are four giant stars – two of spectral type M and two of type G. As we know, it contains the variable star U Sagittarii, a Delta Cephei-type, which lets us know this group of 86 or so stars may have began life together as long ago as 90 million years.

But how many stars are really in there? If you’re using a large aperture telescope, you’re probably detecting the signature of several just beyond the threshold limits. And so has more recent scientific studies. According to a study by A.L. Tadross (et al.) of the National Research Institute of Astronomy and Geophysics:

“The young open star cluster M25 (IC 4725) is located in the direction of the galactic center in a crowded region, near much irregular absorption features on Sagittarius arm. This cluster has some difficult observing problems due to its southern location. The mass data available in the literature have been gathered to re investigate this cluster using most photometric tools to determine its main photometric parameters. More than 220 stars with mean reddening of 0.50 mag and absorption of 1.62 mag are found within the cluster.”

*Core region of the Messier 25 open star cluster. Credit: Sergio Eguivar*

And how many of those stars are surprises? Let’s try a few blue straggler stars. According to a study titled “Blue Stragglers, Be stars and X-ray binaries in open clusters“, by A. Marco (et al):

“Combination of high-precision photometry and spectroscopy allows the detailed study of the upper main sequence in open clusters. We are carrying out a comprehensive study of a number of clusters containing Be stars in order to evaluate the likelihood that a significant number of Be stars form through mass exchange in a binary. Our first results show that most young open clusters contain blue stragglers. In spite of the small number of clusters so far analyzed, some trends are beginning to emerge.In younger open clusters, such as NGC 869 and NGC 663, there are many blue stragglers, most of which are not Be stars. In older clusters, such as IC 4725, the fraction of Be stars among blue stragglers is very high. Two Be blue stragglers are moderately strong X-ray sources, one of them being a confirmed X-ray binaries. Such objects must have formed through binary evolution. We discuss the contribution of mass transfer in a close binary to the formation of both blue stragglers and Be stars.”

History of Observation:

Perhaps we know more about it today than our historic antecedents, but our knowledge of its existence is owed to astronomers like Charles Messier, who took the time to catalog it. As he wrote in his notes:

“In the same night, June 20 to 21, 1764, I have determined the position of another star cluster in the vicinity of the two preceding, between the head and the extremity of the bow of Sagittarius, and almost on the same parallel as the two others: the closest known star is that of the sixth magnitude, the twenty-first of Sagittarius, in the catalog of Flamsteed: this cluster is composed of small stars which one sees with difficulty with an ordinary refractor of 3 feet: it doesn’t contain any nebulosity, and its extension may be 10 minutes of arc. I have determined its position by comparing with the star Mu Sagittarii; its right ascension has been found at 274d 25′, and its declination at 19d 5′ south.”

Finder Chart for M25 (also shown M8->M9, M16->M18, M20->M24 and M28). Credit: freestarcharts

Perhaps William Herschel understood there was more there to be seen, for he commented in his unpublished notes; “Very large, bright, stars and some small, faint ones; I counted 70, and there are many more within no considerable extent.”

Yet, it was Admiral Smyth who really understood what lay beyond. From his observations, he wrote:

“A loose cluster of large and small stars in the Galaxy, between the Archer’s head and Sobieski’s shield; of which a pair og 8th magnitudes, the principle of a set something in the form of a jew’s harp, are above registered. The gathering portion of the group assumes an arched form, and is thickly strewn in the south, on the upper part, where a pretty knot of minute glimmers occupies the center, with much star-dust around. It was discovered in 1764 by Messier, and estimated by him at 10′ in extent: it is 5 deg to the north-east of Mu Sagittarii, and nearly on the parallel of Beta Scorpii, which glimmers far away in the west.”

Locating Messier 25:

Finding Messier 25 with binoculars is quite easy. Simply start at the teapot “lid” star, Lambda, and aim about a fist width almost due north. Here you will encounter a a Cepheid variable – U Sagittarii. This one is a quick change artist, going from magnitude 6.3 to 7.1 in less than seven days, so although it is a cluster member, it may fade on you from time to time as a marker star!

The location of Messier 25. Credit: IAU/Sky & Telescope magazine (Roger Sinnott & Rick Fienberg) — *Location of Messier 25 and other Deep Sky Objects in proximity to the Sagittarius Constellation. Credit: IAU/Sky & Telescope magazine (Roger Sinnott & Rick Fienberg)*

M25 will appear a a loose, but bright association of stars in binoculars and as a faint hazy spot in binoculars – but behold incredible resolution in a telescope. You’ll love the different magnitudes, so stick to around low to medium magnifications to enjoy it most.

As always, here are the quick facts. Enjoy!

Object Name: Messier 25
Alternative Designations: M25, IC 4725
Object Type: Open Galactic Star Cluster
Constellation: Sagittarius
Right Ascension: 18 : 31.6 (h:m)
Declination: -19 : 15 (deg:m)
Distance: 2.0 (kly)
Visual Brightness: 4.6 (mag)
Apparent Dimension: 32.0 (arc min)

We have written many interesting articles about Messier Objects here at Universe Today. Here’s Tammy Plotner’s Introduction to the Messier Objects, , M1 – The Crab Nebula, M8 – The Lagoon Nebula, and David Dickison’s articles on the 2013 and 2014 Messier Marathons.

Be to sure to check out our complete Messier Catalog. And for more information, check out the SEDS Messier Database.

Sources:

October 30, 2016October 31, 2016 by Ken Kremer

SpaceX Makes Progress Replicating Failure that Caused Falcon 9 Pad Explosion

SpaceX Falcon 9 rocket moments after catastrophic explosion destroys the rocket and Amos-6 Israeli satellite payload at launch pad 40 at Cape Canaveral Air Force Station, FL, on Sept. 1, 2016. A static hot fire test was planned ahead of scheduled launch on Sept. 3, 2016. Credit: USLaunchReport

SpaceX is making significant progress in replicating the failure in the helium pressurization system that led to the catastrophic launch pad explosion of the firms Falcon 9 rocket during a routine fueling test at their Florida Space Coast launch complex on September 1.

The problem at the heart of the anomaly appears to be in the helium loading system. However the root cause of the explosion still remains elusive at this time.

“The Accident Investigation Team continues to make progress in examining the anomaly on September 1 that led to the loss of a Falcon 9 and its payload at Launch Complex 40 (LC-40), Cape Canaveral Air Force Station, Florida,” SpaceX announced in an Oct. 28 update.

The company had previously said in a statement issued on Sept. 23 that investigators had determined that a “large breach” in the cryogenic helium system of the second stage liquid oxygen tank likely triggered the catastrophic Falcon 9 launch pad explosion that suddenly destroyed the rocket and Israeli Amos-6 commercial payload during the routine fueling test almost two months ago.

“The root cause of the breach has not yet been confirmed, but attention has continued to narrow to one of the three composite overwrapped pressure vessels (COPVs) inside the LOX tank,” SpaceX explained in the new statement issued on Oct. 28.

“Through extensive testing in Texas, SpaceX has shown that it can re-create a COPV failure entirely through helium loading conditions.”

The helium loading is “mainly affected by the temperature and pressure of the helium being loaded.”

And SpaceX CEO and Founder Elon Musk had previously cited the explosion as “most difficult and complex failure” in the firms history.

“Turning out to be the most difficult and complex failure we have ever had in 14 years,” Musk tweeted on Friday, Sept. 9.

Aerial view of pad and strongback damage at SpaceX Launch Complex-40 as seen from the VAB roof on Sept. 8, 2016 after fueling test explosion destroyed the Falcon 9 rocket and AMOS-6 payload at Cape Canaveral Air Force Station, FL on Sept. 1, 2016. Credit: Ken Kremer/kenkremer.com

The helium loading procedures may well need to be modified, as an outcome of the accident investigation, to enable safe loading conditions.

SpaceX is conducting a joint investigation of the Sept. 1 anomaly with the FAA, NASA, the US Air Force and industry experts who have been “working methodically through an extensive fault tree to investigate all plausible causes.”

The explosion also caused extensive damage to launch pad 40 as well as to the rockets transporter erector, or strongback, that holds the rocket in place until minutes before liftoff, and ground support equipment (GSE) around the pad – as seen in my photos of the pad taken a week after the explosion during the OSIRIS-REx launch campaign.

Fortunately, many other pad areas and infrastructure survived intact or in good condition.

Overview schematic of SpaceX Falcon 9. Credit: SpaceX

The company is conducting an extensive series of ground tests at the firms Texas test site to elucidate as much information as possible as a critical aid to investigators.

“We have conducted tests at our facility in McGregor, Texas, attempting to replicate as closely as possible the conditions that may have led to the mishap.”

The explosion took place without warning at SpaceX’s Space Launch Complex-40 launch facility at approximately 9:07 a.m. EDT on Sept. 1 on Cape Canaveral Air Force Station, Fl, during a routine fueling test and engine firing test as liquid oxygen and RP-1 propellants were being loaded into the 229-foot-tall (70-meter) Falcon 9. Launch of the AMOS-6 comsat was scheduled two days later.

Both the $60 million SpaceX rocket and the $200 million AMOS-6 Israeli commercial communications satellite payload were completely destroyed in a massive fireball that erupted suddenly during the planned pre-launch fueling and hot fire engine ignition test at pad 40 on Sept. 1. There were no injuries since the pad had been cleared.

The rocket disaster was coincidentally captured as it unfolded in stunning detail in a spectacular up close video recorded by my space journalist colleague Mike Wagner at USLaunchReport.

Watch this video:

Video Caption: SpaceX – Static Fire Anomaly – AMOS-6 – 09-01-2016. Credit: USLaunchReport

SpaceX continues to work on root cause and helium loading procedures.

“SpaceX’s efforts are now focused on two areas – finding the exact root cause, and developing improved helium loading conditions that allow SpaceX to reliably load Falcon 9.”

The company also still hopes to resume Falcon 9 launches before the end of 2016.

“Pending the results of the investigation, we continue to work towards returning to flight before the end of the year. Our launch sites at Kennedy Space Center, Florida, and Vandenberg Air Force Base, California, remain on track to be operational in this timeframe.”

At KSC launches will initially take place from pad 39A, the former shuttle pad that SpaceX has leased from NASA.

Pad 40 is out of action until extensive repairs and testing are completed.

SpaceX is renovating Launch Complex 39A at the Kennedy Space Center for launches of the Falcon Heavy and human rated Falcon 9. Credit: Ken Kremer/kenkremer.com

The Sept. 1 calamity was the second Falcon 9 failure within 15 months time and will call into question the rockets overall reliability.

The first Falcon 9 failure involved a catastrophic mid air explosion in the second stage about two and a half minutes after liftoff, during the Dragon CRS-9 cargo resupply launch for NASA to the International Space Station on June 28, 2015 – and witnessed by this author.

Although both incidents involved the second stage, SpaceX maintains that they are unrelated – even as they continue seeking to determine the root cause.

SpaceX must determine the root cause before Falcon 9 launches are allowed to resume. Effective fixes must be identified and effective remedies must be verified and implemented.

Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.

Ken Kremer

Up close view of top of mangled SpaceX Falcon 9 strongback with dangling cables (at right) as seen on Sept. 7 after prelaunch explosion destroyed the rocket and AMOS-6 payload and damaged the pad at Space Launch Complex-40 at Cape Canaveral Air Force Station, FL on Sept. 1, 2016 . Credit: Ken Kremer/kenkremer.com

October 28, 2016October 26, 2019 by Bob King

The Search Is On For Alien Signals Around Tabby’s Star

There’s a remote chance that inexplicable light variations in a star in the Northern Cross may be caused by the works of an alien civilization.

1,480 light years from Earth twinkles one of the greatest mysteries of recent times. There in the constellation Cygnus the Swan, you’ll find a dim, ordinary-looking point of light with an innocent sounding name — Tabby’s Star. Named for Louisiana State University astronomer Tabetha Boyajian, who was the lead author on a paper about its behavior, this star has so confounded astronomers with its unpredictable ups and downs in its brightness, they’ve gone to war on the object, drilling down on it with everything from the Hubble to the monster 393.7-inch (10-meter) Keck Telescope in Hawaii. Continue reading “The Search Is On For Alien Signals Around Tabby’s Star”

October 28, 2016 by Matt Williams

What’s the Most Stable Shape for an Interstellar Lightsail?

Project Starshot, an initiative sponsored by the Breakthrough Foundation, is intended to be humanity's first interstellar voyage. Credit: breakthroughinitiatives.org

In 2015, Russian billionaire Yuri Milner founded Breakthrough Initiatives with the intention of bolstering the search for extra-terrestrial life. Since that time, the non-profit organization – which is backed by Stephen Hawking and Mark Zuckerberg – has announced a number of advanced projects. The most ambitious of these is arguably Project Starshot, an interstellar mission that would make the journey to the nearest star in just 20 years.

This concept involves an ultra-light nanocraft that would rely on a laser-driven sail to achieve speeds of up to 20% the speed of light. Naturally, for such a mission to be successful, a number of engineering challenges have to be tackled first. And according to a recent study by a team of international researchers, two of the most important issues are the shape of the sail itself, and the type of laser involved.

The researchers include Elena Popova of the Skobeltsyn Institute of Nuclear Physics in Moscow; Messoud Efendiev of the Institute of Computational Biology (ICB) at the German Research Center for Environmental Health (GmbH); and Ildar Gabitov of the Skoltech Center for Photonics and Quantum Materials in Moscow. Combining their expertise, they conducted a study that examined various stability models for this proposed mission.

As they indicate in their study, titled “On the Stability of a Space Vehicle Riding on an Intense Laser Beam“, the team ran stability simulations 0n the concept, taking into account the nature of the wafer-sized craft (aka. StarChip), the sail (aka. Lightsail) and the nature of the laser itself. For the sake of these simulations, they also factored in a number of assumptions about Starshot’s design.

These included the notion that the StarChip would be a rigid body (i.e. made up of solid material), that the circular sail would either be flat, spherical or conical (i.e. concave in shape), and that the surface of the sail would reflect the laser light. Beyond this, they played with multiple variations on the design, and came up with some rather telling results.

As Dr. Elena Popova, the lead author on the paper, told Universe Today via email:

“We considered different shapes of sail: a) spherical (coincides with parabolic for small sizes) as most appropriate for final configuration of nanocraft en route; b) conical; c) flat (simplest) (will be seen to be unstable so that even spinning of craft does not help).”

What they found was that the simplest, stable configuration would involve a sail that was spherical in shape. It would also require that the StarChip be tethered at a sufficient distance from the sail, one which would be longer than the curvature radius of the sail itself.

A phased laser array, perhaps in the high desert of Chile, propels sails on their journey. Credit: Breakthrough Initiatives. — *A phased laser array, perhaps in the high desert of Chile, propels sails on their journey. Credit: Breakthrough Initiatives*

“For the sail with almost flat cone shape we obtained similar stability condition,” said Popova. “The nanocraft with flat sail is unstable in every case. It simply corresponds to the case of infinite radius of curvature of the sale. Hence, there is no way to extend center of mass beyond it.”

As for the laser, they considered several how the two main types would effect stability. This included uniform lasers that have a sharp boundary and “Gaussian” beams, which are characterized by high-intensity in the middle that declines rapidly towards the edges. As Dr. Popova stated, they determined that in order to ensure stability – and that the craft wouldn’t be lost to space – a uniform laser was the way to go.

“The nanocraft driven by intense laser beam pressure acting on its Lightsail is sensitive to the torques and lateral forces reacting on the surface of the sail. These forces influence the orientation and lateral displacement of the spacecraft, thus affecting its dynamics. If unstable the nanocraft might even be expelled from the area of laser beam. The most dangerous perturbations in the position of nanocraft inside the beam and its orientation relative to the beam axis are those with direct coupling between rotation and displacement (“spin-orbit coupling”).”

In the end, these were very similar to the conclusions reached by Professor Abraham Loeb and his colleagues at Starshot. In addition to being the Frank B. Baird, Jr. Professor of Science at Harvard University, Prof. Loeb is also the chairman of the Breakthrough Foundation’s Advisory Board. In a study titled “Stability of a Light Sail Riding on a Laser Beam” (published on Sept, 29th, 2016), they too examined what was necessary to ensure a stable mission.

This included the benefits of a conical vs. a spherical sail, and a uniform vs. a Gaussian beam. As Prof. Loeb told Universe Today via email:

“We found that a parachute-shaped sail riding on a Gaussian laser beam is unstable… We show in our paper that a sail shaped as a spherical shell (like a large ping-pong ball) can ride in a stable fashion on a laser beam that is shaped like a cylinder (or 3-4 lasers that establish a nearly circular illumination).”

As for the recommendations about the StarChip being at a sufficient distance from the LightSail, Prof. Loeb and his colleagues are of a different mind. “They argue that in case you attach a weight to the sail that is sufficiently well separated from the parachute, you might make it stable.” he said. “Even if this is true, it is unclear that their proposal is useful because such a configuration is rather complicated to build and launch.”

These are just a few of the engineering challenges facing an interstellar mission. Back in September, another study was released that assessed the risk of collisions and how it might effect the Starshot mission. In this case, the researchers suggested that the sail have a layer of shielding to absorb impacts, and that the laser array be used to clear debris in the LightSail’s path.

These conclusions echoed a similar study produced by Professor Phillip Lubin and his colleagues. A professor at the University of California, Santa Barbara (UCSB), Lubin is also one of the chief architects of Project Starshot and the mind behind the NASA-funded Directed Energy Propulsion for Interstellar Exploraiton (DEEP-IN) project and the Directed Energy Interstellar Study.

When Milner and the science team behind Starshot first announced their intention to create an interstellar spacecraft (in April 2016), they were met with a great deal of enthusiasm and skepticism. Understandably, many believed that such a mission was too ambitious, due to the challenges involved. But with every challenge that has been addressed, both by the Starshot team and outside researchers, the mission architecture has evolved.

At this rate, barring any serious complications, we may be seeing an interstellar mission taking place within a decade or so. And, barring any hiccups in the mission, we could be exploring Alpha Centauri or Proxima b up close within our lifetime!

Further Reading: arXiv

October 28, 2016 by Bob King

Best Photos Yet of the Mars Lander’s Demise

Credit: Schiaparelli lander protected by its heat shield as it enters the Martian atmosphere. Credit: ESA

A closeup of the dark, approximately circular crater about 7.9 feet (2.4 meters) in diameter marking the crash of the Schiaparelli test lander on Mars. The photo was taken on October 25 by NASA's Mars Reconnaissance Lander (MRO). Credit: — A closeup of the dark, approximately circular crater about 7.9 feet (2.4 meters) in diameter that marks the crash of the Schiaparelli test lander on Mars. The new, higher-resolution photo was taken on October 25 by NASA’s Mars Reconnaissance Lander (MRO). A hint of an upraised rim is visible along the crater’s lower left side. The tiny white specks may be pieces of the lander that broke away on impact. The odd dark curving line has yet to be explained. Credit: NASA/JPL-Caltech

What’s the most powerful telescope for observing Mars? A telephoto lens on the HiRise camera on the Mars Reconnaissance Orbiter that can resolve features as small as 3 feet (1-meter) across. NASA used that camera to provide new details of the scene near the Martian equator where Europe’s Schiaparelli test lander crashed to the surface last week.

The Schiaparelli test lander was protected by its heat shield as it descended through the Martian atmosphere at high speed. Credit: ESA

During an October 25 imaging run HiRise photographed three locations where hardware from the lander hit the ground all within about 0.9 mile (1.5 kilometers) of each other. The dark crater in the photo above is what you’d expect if a 660-pound object (lander) slammed into dry soil at more than 180 miles an hour (300 km/h). The crater’s about a foot and a half (half a meter) deep and haloed by dark rays of fresh Martian soil excavated by the impact.

But what about that long dark arc northeast of the crater? Could it have been created by a piece of hardware jettisoned when Schiaparelli’s propellant tank exploded? The rays are curious too. The European Space Agency says that the lander fell almost vertically when the thrusters cut out, yet the asymmetrical nature of the streaks — much longer to the west than east — would seem to indicate an oblique impact. It’s possible, according to the agency, that the hydrazine propellant tanks in the module exploded preferentially in one direction upon impact, throwing debris from the planet’s surface in the direction of the blast, but more analysis is needed. Additional white pixels in the image could be lander pieces or just noise.

This Oct. 25, 2016, image shows the area where the European Space Agency's Schiaparelli test lander reached the surface of Mars, with magnified insets of three sites where components of the spacecraft hit the ground. It is the first view of the site from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter taken after the Oct. 19, 2016, landing event and our highest resolution of the scene to date. Annotations by the author. Click for a full-resolution image. Credit: NASA/JPL-Caltech — This Oct. 25, 2016, image shows the area where the European Space Agency’s Schiaparelli test lander reached the surface of Mars, with magnified insets of three sites where components of the spacecraft hit the ground. It is the first view of the site from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter taken after the Oct. 19, 2016, landing event and our highest resolution of the scene to date. Click for a full-resolution image. Credit: NASA/JPL-Caltech

In the wider shot, several other pieces of lander-related flotsam are visible. About 0.8 mile (1.4 km) eastward, you can see the tiny crater dug out when the heat shield smacked the ground. Several bright spots might be pieces of its shiny insulation. About 0.6 mile (0.9 kilometer) south of the lander impact site, two features side-by-side are thought to be the spacecraft’s parachute and the back shell. NASA plans additional images to be taken from different angle to help better interpret what we see.

The last happy scene for the lander when it still dangled from its chute before dropping and slamming into the surface. Credit: ESA — Schiaparelli dangles from its parachute in this artist’s view. A software error caused the chute to deploy too soon. Credit: ESA

The test lander is part of the European Space Agency’s ExoMars 2016 mission, which placed the Trace Gas Orbiter into orbit around Mars on Oct. 19. The orbiter will investigate the atmosphere and surface of Mars in search of organic molecules and provide relay communications capability for landers and rovers on Mars. Science studies won’t begin until the spacecraft trims its orbit to a 248-mile-high circle through aerobraking, which is expected to take about 13 months.

Everything started out well with Schiaparelli, which successfully transmitted data back to Earth during its descent through the atmosphere, the reason we know that the heat shield separated and the parachute deployed as planned. Unfortunately, the chute and its protective back shell ejected ahead of time followed by a premature firing of the thrusters. And instead of burning for the planned 30 seconds, the rockets shut off after only 3. Why? Scientists believe a software error told the lander it was much closer to the ground than it really was, tripping the final landing sequence too early.

Landing on Mars has never been easy. We’ve done flybys, attempted to orbit the planet or land on its surface 44 times. 15 of those have been landing attempts, with 7 successes: Vikings 1 and 2, Mars Pathfinder, the Spirit and Opportunity rovers, the Phoenix Lander and Curiosity rover. We’ll be generous and call it 8 if you count the 1971 landing of Mars 3 by the then-Soviet Union. It reached the surface safely but shut down after just 20 seconds.

Mars can be harsh, but it forces us to get smart.

**** Want to learn more about Mars and how to track it across the sky? My new book, Night Sky with the Naked Eye, which will be published on Nov. 8, covers planets, satellites, the aurora and much more. You can pre-order it right now at these online stores. Just click an icon to go to the site of your choice – Amazon, Barnes & Noble or Indiebound. It’s currently available at the first two outlets for a very nice discount.

October 28, 2016 by Matt Williams

If it Wasn’t Already Strange Enough, now Saturn’s Hexagon Storm is Changing Color

Saturn makes a beautifully striped ornament in this natural-color image, showing its north polar hexagon and central vortex (Credit: NASA/JPL-Caltech/Space Science Institute)

Ever since the Voyager 2 made its historic flyby of Saturn, astronomers have been aware of the persistent hexagonal storm around the gas giant’s north pole. This a six-sided jetstream has been a constant source of fascination, due to its sheer size and immense power. Measuring some 13,800 km (8,600 mi) across, this weather system is greater in size than planet Earth.

And thanks to the latest data to be provided by the Cassini space probe, which entered orbit around Saturn in 2009, it seems that this storm is even stranger than previously thought. Based on images snapped between 2012 and 2016, the storm appears to have undergone a change in color, from a bluish haze to a golden-brown hue.

The reasons for this change remain something of a mystery, but scientists theorize that it may be the result of seasonal changes due to the approaching summer solstice (which will take place in May of 2017). Specifically, they believe that the change is being driven by an increase in the production of photochemical hazes in the atmosphere, which is due to increased exposure to sunlight.

Natural color images taken by NASA's Cassini wide-angle camera, showing the changing appearance of Saturn's north polar region between 2012 and 2016.. Credit: NASA/JPL-Caltech/Space Science Institute/Hampton University — Natural color images taken by NASA’s Cassini wide-angle camera, showing the changing appearance of Saturn’s north polar region between 2012 and 2016.. Credit: NASA/JPL-Caltech/Space Science Institute/Hampton University

This reasoning is based in part on past observations of seasonal change on Saturn. Like Earth, Saturn experiences seasons because its axis is tilted relative to its orbital plane (26.73°). But since its orbital period is almost 30 years, these seasons last for seven years.

Between November 1995 and August 2009, the hexagonal storm also underwent some serious changes, which coincided with Saturn going from its Autumnal to its Spring Equinox. During this period, the north polar atmosphere became clear of aerosols produced by photochemical reactions, which was also attributed to the fact that the northern polar region was receiving less in the way of sunlight.

However, since that time, the polar atmosphere has been exposed to continuous sunlight, and this has coincided with aerosols being produced inside the hexagon, making the polar atmosphere appear hazy. As Linda J. Spilker, the Cassini mission’s project scientist, told Universe Today via email:

“We have seen dramatic changes in the color inside Saturn’s north polar hexagon in the last 4 years. That color change is probably the result of changing seasons at Saturn, as Saturn moves toward northern summer solstice in May 2017. As more sunlight shines on the hexagon, more haze particles are produced and this haze gives the hexagon a more golden color.”

This diagram shows the main events of Saturn's year, and where in the Saturnian year the Voyager 1 and Cassini missions occurred. Credit: Ralph Lorenz — *Diagram showing he main events of Saturn’s year, and where in the Saturnian year the Voyager 1 and Cassini missions occurred. Credit: Ralph Lorenz*

All of this has helped scientists to test theoretical models of Saturn’s atmosphere. In the past, it has been speculated that this six-sided storm acts as a barrier that prevents outside haze particles from entering. The previous differences in color – the planet’s atmosphere being golden while the polar storm was darker and bluish – certainly seemed to bear this out.

The fact that it is now changing color and starting to look more like the rest of the atmosphere could mean that the chemical composition of the polar region is now changing and becoming more like the rest of the planet. Other effects, which include changes in atmospheric circulation (which are in turn the result of seasonally shifting solar heating patterns) might also be influencing the winds in the polar regions.

Needless to say, the giant planets of the Solar System have always been a source of fascination for scientists and astronomers. And if these latest images are any indication, it is that we still have much to learn about the dynamics of their atmospheres.

“It is very exciting to see this transformation in Saturn’s hexagon color with changing seasons,” said Spilker. “With Saturn seasons over 7 years long, these new results show us that it is certainly worth the wait.”

R. G. French (Wellesley College) et al., NASA, ESA, and The Hubble Heritage Team (STScI/AURA) — *The seasons on Saturn, visualized with images taken by the Hubble Heritage Team. Credit: R. G. French (Wellesley College) et al./NASA/ESA/Hubble Heritage Team (STScI/AURA)*

It also shows that Cassini, which has been in operation since 1997, is still able to provide new insights into Saturn and its system of moons. In recent weeks, this included information about seasonal variations on Titan, Saturn’s largest moon. By April 22nd, 2017, the probe will commence its final 22 orbits of Saturn. Barring any mission extensions, it is scheduled enter into Saturn’s atmosphere (thus ending its mission) on Sept. 15th, 2017.

Further Reading: NASA/JPL/Caltech