Universe Today

October 13, 2017 by Matt Williams

Debris Disks Around Stars Could Point the Way to Giant Exoplanets

This artist's rendering shows a large exoplanet causing small bodies to collide in a disk of dust. Credit: NASA/JPL-Caltech

According to current estimates, there could be as many as 100 billion planets in the Milky Way Galaxy alone. Unfortunately, finding evidence of these planets is tough, time-consuming work. For the most part, astronomers are forced to rely on indirect methods that measure dips in a star’s brightness (the Transit Method) of Doppler measurements of the star’s own motion (the Radial Velocity Method).

Direct imaging is very difficult because of the cancelling effect stars have, where their brightness makes it difficult to spot planets orbiting them. Luckily a new study led by the Infrared Processing and Analysis Center (IPAC) at Caltech has determined that there may be a shortcut to finding exoplanets using direct imaging. The solution, they claim, is to look for systems with a circumstellar debris disk, for they are sure to have at least one giant planet.

The study, titled “A Direct Imaging Survey of Spitzer Detected Debris Disks: Occurrence of Giant Planets in Dusty Systems“, recently appeared in The Astronomical Journal. Tiffany Meshkat, an assistant research scientist at IPAC/Caltech, was the lead author on the study, which she performed while working at NASA’s Jet Propulsion Laboratory as a postdoctoral researcher.

A circumstellar disk of debris around a mature stellar system could indicate the presence of Earth-like planets. Credit: NASA/JPL — *Artist’s impression of circumstellar disk of debris around a distant star. Credit: NASA/JPL*

For the sake of this study, Dr. Meshkat and her colleagues examined data on 130 different single-star systems with debris disks, which they then compared to 277 stars that do not appear to host disks. These stars were all observed by NASA’s Spitzer Space Telescope and were all relatively young in age (less than 1 billion years). Of these 130 systems, 100 had previously been studied for the sake of finding exoplanets.

Dr. Meshkat and her team then followed up on the remaining 30 systems using data from the W.M. Keck Observatory in Hawaii and the European Southern Observatory’s (ESO) Very Large Telescope (VLT) in Chile. While they did not detect any new planets in these systems, their examinations helped characterize the abundance of planets in systems that had disks.

What they found was that young stars with debris disks are more likely to also have giant exoplanets with wide orbits than those that do not. These planets were also likely to have five times the mass of Jupiter, thus making them “Super-Jupiters”. As Dr. Meshkat explained in a recent NASA press release, this study will be of assistance when it comes time for exoplanet-hunters to select their targets:

“Our research is important for how future missions will plan which stars to observe. Many planets that have been found through direct imaging have been in systems that had debris disks, and now we know the dust could be indicators of undiscovered worlds.”

*This artist’s conception shows how collisions between planetesimals can create additional debris. Credit: NASA/JPL-Caltech*

This study, which was the largest examination of stars with dusty debris disks, also provided the best evidence to date that giant planets are responsible for keeping debris disks in check. While the research did not directly resolve why the presence of a giant planet would cause debris disks to form, the authors indicate that their results are consistent with predictions that debris disks are the products of giant planets stirring up and causing dust collisions.

In other words, they believe that the gravity of a giant planet would cause planestimals to collide, thus preventing them from forming additional planets. As study co-author Dimitri Mawet, who is also a JPL senior research scientist, explained:

“It’s possible we don’t find small planets in these systems because, early on, these massive bodies destroyed the building blocks of rocky planets, sending them smashing into each other at high speeds instead of gently combining.”

Within the Solar System, the giant planets create debris belts of sorts. For example, between Mars and Jupiter, you have the Main Asteroid Belt, while beyond Neptune lies the Kuiper Belt. Many of the systems examined in this study also have two belts, though they are significantly younger than the Solar System’s own belts – roughly 1 billion years old compared to 4.5 billion years old.

*Artist’s impression of Beta Pictoris b. Credit: ESO L. Calçada/N. Risinger (skysurvey.org)*

One of the systems examined in the study was Beta Pictoris, a system that has a debris disk, comets, and one confirmed exoplanet. This planet, designated Beta Pictoris b, which has 7 Jupiter masses and orbits the star at a distance of 9 AUs – i.e. nine times the distance between the Earth and the Sun. This system has been directly imaged by astronomers in the past using ground-based telescopes.

Interestingly enough, astronomers predicted the existence of this exoplanet well before it was confirmed, based on the presence and structure of the system’s debris disk. Another system that was studied was HR8799, a system with a debris disk that has two prominent dust belts. In these sorts of systems, the presence of more giant planets is inferred based on the need for these dust belts to be maintained.

This is believed to be case for our own Solar System, where 4 billion years ago, the giant planets diverted passing comets towards the Sun. This resulted in the Late Heavy Bombardment, where the inner planets were subject to countless impacts that are still visible today. Scientists also believe that it was during this period that the migrations of Jupiter, Saturn, Uranus and Neptune deflected dust and small bodies to form the Kuiper Belt and Asteroid Belt.

Dr. Meshkat and her team also noted that the systems they examined contained much more dust than our Solar System, which could be attributable to their differences in age. In the case of systems that are around 1 billion years old, the increased presence of dust could be the result of small bodies that have not yet formed larger bodies colliding. From this, it can be inferred that our Solar System was once much dustier as well.

*Artist’s concept of the multi-planet system around HR 8799, initially discovered with Gemini North adaptive optics images. Credit: Gemini Observatory/Lynette Cook”*

However, the authors note is also possible that the systems they observed – which have one giant planet and a debris disk – may contain more planets that simply have not been discovered yet. In the end, they concede that more data is needed before these results can be considered conclusive. But in the meantime, this study could serve as an guide as to where exoplanets might be found.

As Karl Stapelfeldt, the chief scientist of NASA’s Exoplanet Exploration Program Office and a co-author on the study, stated:

“By showing astronomers where future missions such as NASA’s James Webb Space Telescope have their best chance to find giant exoplanets, this research paves the way to future discoveries.”

In addition, this study could help inform our own understanding of how the Solar System evolved over the course of billions of years. For some time, astronomers have been debating whether or not planets like Jupiter migrated to their current positions, and how this affected the Solar System’s evolution. And there continues to be debate about how the Main Belt formed (i.e. empty of full).

Last, but not least, it could inform future surveys, letting astronomers know which star systems are developing along the same lines as our own did, billions of years ago. Wherever star systems have debris disks, they an infer the presence of a particularly massive gas giant. And where they have a disk with two prominent dust belts, they can infer that it too will become a system containing many planets and and two belts.

Further Reading: NASA, The Astrophysical Journal

October 12, 2017October 12, 2017 by Matt Williams

Ancient Hydrothermal Vents Found on Mars, Could Have Been a Cradle for Life

MOLA topographic data, colorized to show the maximum (1,100?m) and minimum (700?m) level of an ancient sea. Credit: NASA/Joseph R. Michalski (et al.)/Nature Communications

It is now a well-understood fact that Mars once had quite a bit of liquid water on its surface. In fact, according to a recent estimate, a large sea in Mars’ southern hemisphere once held almost 10 times as much water as all of North America’s Great Lakes combined. This sea existed roughly 3.7 billion years ago, and was located in the region known today as the Eridania basin.

However, a new study based on data from NASA’s Mars Reconnaissance Orbiter (MRO) detected vast mineral deposits at the bottom of this basin, which could be seen as evidence of ancient hot springs. Since this type of hydrothermal activity is believed to be responsible for the emergence of life on Earth, these results could indicate that this basin once hosted life as well.

The study, titled “Ancient Hydrothermal Seafloor Deposits in Eridania Basin on Mars“, recently appeared in the scientific journal Nature Communications. The study was led by Joseph Michalski of the Department of Earth Sciences and Laboratory for Space Research at the University of Hong Kong, along with researchers from the Planetary Science Institute, the Natural History Museum in London, and NASA’s Johnson Space Center.

*The Eridania basin of southern Mars is believed to have held a sea about 3.7 billion years ago, with seafloor deposits likely resulting from underwater hydrothermal activity. Credit: NASA*

Together, this international team used data obtained by the MRO’s Compact Reconnaissance Spectrometer for Mars (CRISM). Since the MRO reached Mars in 2006, this instrument has been used extensively to search for evidence of mineral residues that form in the presence of water. In this respect, CRISM was essential for documenting how lakes, ponds and rivers once existed on the surface of Mars.

In this case, it identified massive mineral deposits within Mars’ Eridania basin, which lies in a region that has some of the Red Planet’s most ancient exposed crust. The discovery is expected to be a major focal point for scientists seeking to characterize Mars’ once-warm and wet environment. As Paul Niles of NASA’s Johnson Space Center said in a recent NASA press statement:

“Even if we never find evidence that there’s been life on Mars, this site can tell us about the type of environment where life may have begun on Earth. Volcanic activity combined with standing water provided conditions that were likely similar to conditions that existed on Earth at about the same time — when early life was evolving here.”

Today, Mars is a cold, dry place that experiences no volcanic activity. But roughly 3.7 billion years ago, the situation was vastly different. At that time, Mars boasted both flowing and standing bodies of water, which are evidenced by vast fluvial deposits and sedimentary basins. The Gale Crater is a perfect example of this since it was once a major lake bed, which is why it was selected as the landing sight for the Curiosity rover in 2012.

*Illustrates showing the origin of some deposits in the Eridania basin of southern Mars resulting from seafloor hydrothermal activity more than 3 billion years ago. Credit: NASA*

Since Mars had both surface water and volcanic activity during this time, it would have also experienced hydrothermal activity. This occurs when volcanic vents open into standing bodies of water, filling them with hydrated minerals and heat. On Earth, which still has an active crust, evidence of past hydrothermal activity cannot be preserved. But on Mars, where the crust is solid and erosion is minimal, the evidence has been preserved.

“This site gives us a compelling story for a deep, long-lived sea and a deep-sea hydrothermal environment,” Niles said. “It is evocative of the deep-sea hydrothermal environments on Earth, similar to environments where life might be found on other worlds — life that doesn’t need a nice atmosphere or temperate surface, but just rocks, heat and water.”

Based on their study, the researchers estimate that the Eridania basin once held about 210,000 cubic km (50,000 cubic mi) of water. Not only is this nine times more water than all of the Great Lakes combined, it is as much as all the other lakes and seas on ancient Mars combined. In addition, the region also experienced lava flows that existed after the sea is believed to have disappeared.

From the CRISM’s spectrometer data, the team identified deposits of serpentine, talc and carbonate. Combined with the shape and texture of the bedrock layers, they concluded that the sea floor was open to volcanic fissures. Beyond indicating that this region could have once hosted life, this study also adds to the diversity of the wet environments which are once believed to have existed on Mars.

A scale model compares the volume of water contained in lakes and seas on the Earth and Mars to the estimated volume of water contained in an ancient Eridania sea. Credit: JJoseph R. Michalski (et al.)/Nature Communications

Between evidence of ancient lakes, rivers, groundwater, deltas, seas, and volcanic eruptions beneath ice, scientists now have evidence of volcanic activity that occurred beneath a standing body of water (aka. hot springs) on Mars. This also represents a new category for astrobiological research, and a possible destination for future missions to the Martian surface.

The study of hydrothermal activity is also significant as far as finding sources of extra-terrestrial, like on the moons of Europa, Enceladus, Titan, and elsewhere. In the future, robotic missions are expected to travel to these worlds in order to peak beneath their icy surfaces, investigate their plumes, or venture into their seas (in Titan’s case) to look for the telltale traces of basic life forms.

The study also has significance beyond Mars and could aid in the study of how life began here on Earth. At present, the earliest evidence of terrestrial life comes from seafloor deposits that are similar in origin and age to those found in the Eridania basin. But since the geological record of this period on Earth is poorly preserved, it has been impossible to determine exactly what conditions were like at this time.

Given Mars’ similarities with Earth, and the fact that its geological record has been well-preserved over the past 3 billion years, scientists can look to mineral deposits and other evidence to gauge how natural processes here on Earth allowed for life to form and evolve over time. It could also advance our understanding of how all the terrestrial planets of the Solar System evolved over billions of years.

Further Reading: NASA

October 12, 2017 by David Dickinson

Tales of the King: Watch as the Moon Occults Regulus for North America This Weekend

The Moon occults Regulus on July 25th, 2017. The Moon also occulted the star shortly after the August 21st total solar eclipse. Credit and copyright; @Shahgazer (Shahrin Ahmad).

Up early Sunday morning? Or perhaps, as we often do, you’re “pulling an all-nighter,” out observing until the break of dawn. Well, the clockwork celestial mechanics of the Universe has a treat in store on the morning of October 15^th, as the waning crescent Moon occults (passes in front of) the bright star Regulus (Alpha Leonis, the “Little King” or “Heart of the Lion”) for the contiguous United States, Mexico and southern Canada.

The visibility footprint for Sunday’s occultation. The white solid lines show where the occultation occurs under dark skies, blue marks twilight, and broken lines represent where the event occurs under daytime skies. Credit: Occult 4.2.

You might call this one the “Great American Occultation,” as it takes a similar track to a certain total solar eclipse and another occultation of the bright star Aldebaran earlier this year. The Moon is a 20% illuminated waning crescent during Sunday’s occultation, about the best phase for such an event, as you’ll also get a nice contrasting Earthshine or Ashen light on dark nighttime limb of the Moon. That’s sunlight from the waxing gibbous Earth, illuminating the (cue Pink Floyd) Dark Side of the Moon.

Moon versus Regulus shortly after Sunday’s occultation as seen from Spring Hill, Florida. Stellarium.

Early morning occultations always see the target star or planet ingress (passing behind) the oncoming bright limb of the waning Moon, then egress (reappearing) from behind its dark limb. During waxing evening occultations, the reverse is true, as the dark limb of the Moon leads the way. The Moon will be 53 degrees west of the Sun during the event, and folks in the western U.S. will see the occultation lower to the eastern horizon under dark skies, while observers from Florida to the Great Lakes will see the event transpire under twilight skies and observers in the U.S. northeast will see the occultation finish up after sunrise. Shining at magnitude +1.4, you’ll be able to see the disappearance and reappearance of Regulus with the unaided eye, though events on the dark limb are always more dramatic. And you may just be able to spy Regulus in the daytime post sunrise near the Moon after the occultation, using binoculars or a telescope.

The northern limit graze line path for Sunday’s occultation. Click here for a Google interactive map. Credit: IOTA

Observers along a line running from Oregon through Lake of the Woods, above the Great Lakes and north of New Brunswick are also in for a treat as you just might be able to catch a rare grazing occultation of Regulus, (see the video below) as the star’s light shines down through those lunar valleys and gets blocked by mountain peaks along the limb of the Moon. Such an event can be quite dramatic to watch, as the star light winks in and out during the very last second of its 79 light year journey.

A look at the occultation circumstances for selected locations tells the story. The International Occultation Timing Association has a full list for locales across North America.

	Ingress	Egress	Moon Alt start/end
Boise, Idaho	9:48 UT	10:03 UT	3 deg / 6 deg
Tuscon, Arizona	(before Moonrise)	10:14 UT	NA / 10 deg
Mexico City, Mexico	9:19 UT	10:06 UT	6 deg / 17 deg
Tampa, Florida	9:24 UT	10:32 UT	23 deg / 39 deg
St. Louis, Missouri	9:29 UT	10:26 UT	18 deg / 29 deg
Boston, Massachusetts	9:50 UT	10:44 UT	36 deg / 45 deg
Toronto, Canada	9:47 UT	10:32 UT	29 / 37 deg

The Moon is in the midst of a cycle of occultations of Regulus running from December 18^th, 2016 to the final one for the cycle on April 24^th, 2018. This is number 12 in a series of 19 events, and the best pre-dawn occultation of Regulus for the United States in the current cycle.

US cloud cover percentages, a few hours before the occultation. Credit: NOAA

The Moon can occult four bright +1^st magnitude stars during the current epoch: Regulus, Antares, Spica and Aldebaran. And though Regulus lies closest to the ecliptic plane, it actually gets occulted the least of any 1^st magnitude star in the 21^st century, with only 220 events. The Moon actually also occulted the bright star Pollux up until almost two millennia ago, and will resume doing so again in the future.

Occultations are easy to observe, and one of the few times (including eclipses) were you can see the motion of the Moon, in real time. The Moon moves its own diameter (30′ or half a degree) per hour, and the reemergence of the bright star will be an abrupt “lights back on” for Regulus. Does it seem to linger a bit between the horns of the crescent Moon? This often reported optical illusion is called the Coleridge Effect, from a line from Samuel Coleridge’s (not Iron Maiden’s) Rime of the Ancient Mariner:

While clome above the Eastern bar

The horned Moon, with one bright star

Almost atween the tips.

Happen to see Regulus “a clome ‘atween the tips?” We also like to refer to this as the ‘Protor and Gamble effect’ due to the company’s traditional star-filled logo.

Occultations also adorn the flags of many Middle Eastern countries. The star and crescent of Islam traces back to antiquity, but was said to have been adapted for the Turkish flag after Sultan Alp Arslan witnessed a close pairing shortly after the Battle of Manzikert on August 26^th, 1071 AD. Though Venus is usually stated as the legendary “star,” Regulus was in fact, just a few degrees away from the Moon on the very same morning… perhaps adding some credence to a major legend vexing vexillology?

The Moon and Regulus on the morning of August 26th, 1071 AD. Stellarium.

Of course, we may never truly know just what Sultan Arsulan saw. A more recent occultation tale was featured in the November 2017 issue of Sky and Telescope, positing the an occultation of Aldebaran by the Moon on March 7^th, 1974 was the source of William Wilkins’ alleged “Volcano on the Moon…” the timing is certainly right, though one wonders how a skilled observer like Wilkins could be fooled by a prominent star (wistful thinking, maybe?)

Recording an occultation is as easy as aiming a video camera at the Moon through a telescope and letting it run. Start early, and make sure you’ve got the contrast between the bright limb of the Moon and the star adjusted, so both appear in the frame. We like to have WWV radio running in the background for an accurate time hack on the video.

Regulus also has a suspected (though never seen) white dwarf companion. Such a star should shine at +12^th magnitude or so… and just might make a very brief appearance on the dark limb of the Moon during egress. One total unknown is its position angle, which is a big wild card, but you just never know… its worth examining that video afterwards, especially if you’re shooting at a high frame rate.

…and speaking of occultations, we’re in the midst of combing through near double occultations of bright stars and planets out to 3000 A.D… hey, it’s what we do for fun. Anyhow, we’re tweeting these out as @Astroguyz as we find ’em, one per day. As a teaser, I give you this grazing occultation of Venus and Regulus over Siberia coming right up in 2025:

The Moon occults Venus and Regulus in 2025. Stellarium.

If nothing else, the cosmic grin of a planet, star and crescent Moon does hint at the Universe’s strange sense of humor.

October 11, 2017October 12, 2017 by Ken Kremer

SpaceX Stages Stunning Sunset Blastoff as Recycled Falcon 9 Soars to Orbit with SES/EchoStar HDTV Sat; Booster Re-Lands at Sea

SpaceX's reusable rockets are bringing down the cost of launching things into space, but the cost is still prohibitive. Any weight savings contribute to missions feasibility, including a reduction in food supplies for long space journeys. In this image, a SpaceX Falcon 9 recycled rocket lifts off at sunset at 6:53 PM EDT on 11 Oct 2017. Credit: Ken Kremer/Kenkremer.com

SpaceX Falcon 9 recycled rocket lifts off at sunset at 6:53 PM EDT on 11 Oct 2017 carrying SES-11/EchoStar 105 HDTV commercial comsat to geosynchronous transfer orbit from Launch Complex 39A at NASA’s Kennedy Space Center, FL- as seen from the pad perimeter. Credit: Ken Kremer/Kenkremer.com

KENNEDY SPACE CENTER, FL – SpaceX staged a stunning sunset blastoff this evening Oct. 11, of the commercial SES-11/EchoStar 105 HDTV satellite that will serve the everyday needs of millions of customers across North America as it soared to geostationary orbit on a recycled Falcon 9 from the Florida Space Coast.

Minutes later the now doubly ‘flight-proven’ booster safely made its way back to Cape Canaveral after reigniting its engines to carry out another upright soft landing and recovery – that potentially sets the stage for an unprecedented third launch.

The private SES-11/EchoStar 105 communications satellite mission made an on time liftoff of the recycled first stage booster at dinnertime Wednesday Oct. 11 at 6:53 p.m. EDT from seaside Launch Complex 39A at NASA’s Kennedy Space Center in Florida.

SpaceX successfully delivered the nearly six ton EchoStar 105/SES-11 joint mission satellite for SES and ExchoStar to geostationary transfer orbit some 22,000 miles (36,000 kilometers) above the equator.

“Successful deployment of EchoStar 105/SES-11 to geostationary transfer orbit confirmed,” said SpaceX.

Remarkably today’s launch was the second launch for SpaceX this week following Monday’s Falcon 9 launch from Vandenberg AFB, Ca., carrying 10 Iridium-NEXT satellites to orbit – and a record setting 15th of 2017!

Sunset blastoff of SpaceX Falcon 9 recycled rocket at 6:53 PM EDT on 11 Oct 2017 carrying SES-11/EchoStar 105 HD TV commercial comsat to geosynchronous transfer orbit from Launch Complex 39A at NASA’s Kennedy Space Center, FL- as seen from the famous countdown clock. This launch counts as third reflight of a liquid fueled orbit class rocket. Credit: Ken Kremer/Kenkremer.com

The launch, landing and satellite deployment were broadcast live on a SpaceX hosted webcast.

The weather was near perfect and there was scarcely a cloud in the sky. Space enthusiasts who traveled far and wide from around the globe to witness a launch were richly rewarded with time and money well spent.

That’s in stark contrast to the horrible weather conditions existing just days ago that forced a part of weather scrubs for the ULA Atlas V. Launch of the NROL-52 spy satellite is currently rescheduled for Sat., Oct 14.

EchoStar 105/SES-11 is a high-powered hybrid Ku and C-band communications satellite launching as a dual-mission satellite for US-based operator EchoStar and Luxembourg-based operator SES.

The used two stage 229-foot-tall (70-meter) Falcon 9 rocket was rolled out to pad 39A Tuesday to ready it for today’s liftoff.

The EchoStar 105/SES-11 spacecraft was built by Airbus and shipped from the Airbus facilities in Toulouse, France to Cape Canaveral, FL for flight processing.

SES-11/EchoStar 105 communications satellite manufactured by Airbus. Credit: SES

The satellite was successfully deployed as planned approximately 36 minutes after liftoff.

“SES-11 is a high-powered communications satellite designed to especially accelerate the development of the US video neighbourhood, and the delivery of HD and UHD channels. Optimised for digital television delivery, SES-11 joins SES-1 and SES-3 at the centre of its robust North American orbital arc, which reaches more than 100 million TV homes. Together with SES-1 and SES-3, SES-11 will be utilised for the expansion of the North America Ultra HD platform,” according to SES.

“SES-11 offers comprehensive coverage over North America, including Hawaii, Mexico and the Caribbean, and will also empower businesses and governments to capture new opportunities and expand their reach across the region.”

The 5,200 kg (11,500 pounds) satellite was encapsulated inside the payload fairing and integrated with the Falcon 9 rocket.

Up close view of payload fairing encapsulating SES-11/EchoStar 105 UHD TV commercial comsat atop ‘flight-proven’ SpaceX Falcon 9 rocket. Liftoff is slated for is 6:53 p.m. ET, Oct. 11, 2017 from Launch Complex 39A at the Kennedy Space Center, FL. Credit: Ken Kremer/kenkremer.com

This is only the third recycled SpaceX Falcon 9 ever to be launched from Pad 39A.

SpaceX Falcon 9 recycled rocket carrying SES-11/EchoStar 105 UHD TV commercial comsat raised erect atop Launch Complex 39A as flock of birds flies by at the Kennedy Space Center, FL, is poised for sunset liftoff on 11 Oct 2017 on world’s third reflight of a liquid fueled orbit class rocket. As seen from the pad perimeter. Credit: Ken Kremer/Kenkremer.com

SES was the first company to ever fly a payload on a ‘flight-proven’ Falcon 9. The SES-10 satellite lifted off successfully this spring on March 30, 2017.

The second reflown booster successfully launched the BulgariaSat-1 a few months later.

Pad 39A has been repurposed by SpaceX from its days as a NASA shuttle launch pad.

After the 156 foot tall first stage booster completed its primary mission task, SpaceX engineers guided it to a second landing on the tiny football field sized OCISLY drone ship for a soft touchdown some eight and a half minutes after liftoff.

“Falcon 9 first stage has landed on Of Course I Still Love You — third successful mission with a flight-proven orbital class rocket,” said SpaceX.

This marked the 18th successful landing of a recovered Falcon 9 first stage booster.

This booster originally flew on the NASA Dragon CRS-10 resupply mission to the International Space Station in February of this year.

OCISLY or “Of Course I Still Love You” left Port Canaveral several days ahead of the planned Oct. 11 launch and was prepositioned in the Atlantic Ocean some 400 miles (600 km) off the US East coast, just waiting for the boosters 2nd approach and pinpoint propulsive soft landing.

The booster was outfitted with four grid fins and four landing legs to accomplish the pinpoint touchdown on the barge at sea.

The last SpaceX Falcon 9 launch from KSC took place on Sep. 7 carrying the USAF X-37B military space plane to orbit just ahead of Hurricane Irma.

Watch for Ken’s continuing onsite coverage of SpaceX SES-11, ULA NROL-52 and NASA and space mission reports direct from the Kennedy Space Center and Cape Canaveral Air Force Station, Florida.

To date SpaceX has successfully recovered 18 first stage boosters by land and sea.

The SES-11 stage is expected back in Port Canaveral in a few days if all goes well.

SpaceX Falcon 9 Booster leaning atop OCISLY droneship upon which it landed after 23 June launch from KSC floats into Port Canaveral, FL, on 29 June 2017, hauled by tugboat as seen from Jetty Park Pier. Credit: Ken Kremer/kenkremer.com

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

Ken Kremer

Deployment of SES-11/EchoStar 105 communications satellite from SpaceX 2nd stage. Credit: SpaceX

October 11, 2017October 25, 2017 by Fraser Cain

Weekly Space Hangout – Oct 11, 2017: SpaceX From The Ground Up by Chris Prophet

Hosts:
Fraser Cain (universetoday.com / @fcain)
Dr. Paul M. Sutter (pmsutter.com / @PaulMattSutter)
Dr. Kimberly Cartier (KimberlyCartier.org / @AstroKimCartier )
Dr. Morgan Rehnberg (MorganRehnberg.com / @MorganRehnberg ChartYourWorld.org)

Special Guest:
Chris Prophet is the author of SpaceX From the Ground Up in which he examines SpaceX’s commercial plan to colonise Mars in the 2020’s, including their many technical innovations, culminating in the Mars Colonial Transporter. Chris began his career as a semiconductor fabrication design engineer and ultimately went on to specialize in technical acquisitions and publishing. Chris authored numerous periodical stories before graduating to full-length stories with a contemporary Sci-fi influence.

Announcements:

If you would like to join the Weekly Space Hangout Crew, visit their site here and sign up. They’re a great team who can help you join our online discussions!

We record the Weekly Space Hangout every Wednesday at 5:00 pm Pacific / 8:00 pm Eastern. You can watch us live on Universe Today, or the Weekly Space Hangout YouTube page – Please subscribe!

October 11, 2017October 11, 2017 by Nancy Atkinson

Watch a House-Sized Asteroid Pass Close to Earth Tonight (October 11/12)

Asteroid 2012 TC4 captured remotely on October 11, 2017 from the iTelescope SRO Observatory. Credit and copyright: Ernesto Guido/Remanzacco Observatory.

On Oct. 12, a house-size asteroid will pass quite close to Earth – only 26,000 miles (42,000 kilometers) away. This is just above the orbital altitude of communications satellites and a little over one-tenth the distance to the Moon. But not to fear, it has no chance of hitting Earth.

Artists concept of Asteroid 2012 TC4’s close pass of Earth on Oct. 12, 2017. Based on continuing observations, scientists have determined that it will pass the Earth at a distance of about 26,000 miles (42,000 kilometers). Credits: NASA/JPL-Caltech

Asteroid 2012 TC4 was discovered almost 4 years ago to the day, on October 4, 2012, just a week before it made another close pass by Earth.

With a little more advance notice this time around, NASA and asteroid trackers around the world are using the close pass to test their ability to operate as a coordinated International Asteroid Warning Network. This is a growing global observing network to communicate and coordinate their optical and radar observations in a real scenario.

“Asteroid trackers are using this flyby to test the worldwide asteroid detection and tracking network, assessing our capability to work together in response to finding a potential real asteroid-impact threat,” said Michael Kelley, program scientist and NASA lead for the TC4 observation campaign. You can read more details about the observing campaign in our previous article.

You can watch it pass by too, if you have a at least an 8 inch telescope, according to our David Dickinson, who has a very informative post about 2012 TC4 at Sky & Telescope.

Closest approach will be at on October 12, 2017, at 5:41 Universal Time (1:41 a.m. EDT).

You can also watch a couple of webcasts of the pass:

Virtual Telescope will have a live feed, and the Slooh Telescope crew will also host a live feed starting tonight at 8 pm EDT on Oct. 11.

2012 TC4 is estimated to be 45 to 100 feet (15 to 30 meters) in size.

NASA’s Asteroid Watch says that no asteroid currently known is predicted to impact Earth for at least the next 100 years.

More info at NASA’s website.

October 11, 2017October 11, 2017 by Nancy Atkinson

Dwarf Planet Haumea Has a Ring

Artist concept of Haumea, with the correct proportions of the main body and the ring. The ring is at a distance of 2287 kilometers from the center of the main body and is darker than the surface of the dwarf planet itself. Credit: Instituto de Astrofísica de Andalucía.

A unique opportunity to study the dwarf planet Haumea has led to an intriguing discovery: Haumea is surrounded by a ring.

Add this to the already long list of unique things about the weird-shaped world with a dizzying rotation and a controversial discovery.

On January 21, 2017 Haumea passed in front of a distant star, in an event known as an occultation. The background star can – pardon the pun – shine a light on the object passing in front, providing information about a distant object — such as size, shape, and density — that is otherwise difficult to obtain. Since an occultation with Haumea had never been observed before, scientists were first eager, and then surprised.

“One of the most interesting and unexpected findings was the discovery of a ring around Haumea,” said said Pablo Santos-Sanz, from the Institute of Astrophysics of Andalusia (IAA-CSIC) in a statement.

This is the first time a ring has been discovered around a trans-neptunian object, and the team said this discovery shows that the presence of rings could be much more common than was previously thought, in our Solar System as well as in other planetary systems.

“Twelve telescopes from ten different European observatories converged on the phenomenon,” said José Luis Ortiz, who led the observational effort, and is also from IAA-CSIC. “This deployment of technical means allowed us to reconstruct with a very high precision the shape and size of dwarf planet Haumea, and discover to our surprise that it is considerably bigger and less reflecting than was previously believed. It is also much less dense than previously thought, which answered questions that had been pending about the object.”

The team said their data shows that the egg-shaped Haumea measures 2,320 kilometers in its largest axis. Previous estimates from various observations put the size at roughly 1,400 km. It takes 3.9 hours for Haumea rotate around its axis, much less than any other body in the Solar System that measures more than a hundred kilometers long. This rotational speed likely caused Haumea to flatten out, giving it an ellipsoid shape. It orbits the Sun in an elliptical loop that takes 284 years to complete. Additionally Haumea has two small moons.

Artist’s impression of the dwarf planet Haumea and its moons, Hi’aka and Namaka. Credit: NASA

Ortiz and team say their data shows the newly discovered ring lies on the equatorial plane of the dwarf planet, and it “displays a 3:1 resonance with respect to the rotation of Haumea, which means that the frozen particles which compose the ring rotate three times slower around the planet than it rotates around its own axis.”

Ortiz says there might be a few possible explanations for the formation of the ring; it may have originated in a collision with another object, or in the dispersal of surface material due to the planet’s high rotational speed.

Of course, other objects in our Solar System have rings: all the giant planets have rings, with Saturn’s being the most massive and well know. But small centaur asteroids located between Jupiter and Neptune were found to have rings, too.
“Now we have discovered that bodies even farther away than the centaurs, bigger and with very different general characteristics, can also have rings,” said Santos-Sanz.

You may recall there was great controversy over the discovery of Haumea. The discovery was originally announced in 2005 by Mike Brown from Caltech, along with his colleagues Chad Trujillo of the Gemini Observatory in Mauna Kea, Hawaii, and David Rabinowitz, of Yale University.

But then Ortiz and Santos-Sanz attempted to scoop Brown et. al by sending in their claim to discovery to the Minor Planet Center before Brown’s paper was published. It was later learned that Ortiz and colleagues had accessed the Caltech observing logs remotely, looking at when and where Brown was looking with his telescopes. Ortiz and team initially denied the claims, but later conceded accessing the observation logs, maintaining they were just verifying whether they had discovered a new object in observations from 2003.

I asked Brown today if anything was ever officially resolved about the controversy.

“I think the resolution is that it is generally accepted that they stole our positions, but no one wants to think about it anymore,” he said via email.

But the discovery of a ring Haumea, Brown said, looks solid.

“I will admit to being wary of anything Ortiz says, so I checked the data very carefully,” Brown said. “Even I have to agree that the detection looks pretty solid. Haumea is weird, so it’s less surprising than, say, finding rings around something like Makemake. But, still, this was not something I was expecting!”

Sources: IAA-CSIC, Nature, email exchange with Brown.

October 11, 2017October 11, 2017 by Matt Williams

This Meteorite Came From a Volcano on Mars

A sample of nakhlite, a type of volcanic terrain that came to Earth as a Martian meteorite. Credit: University of Glasgow

Today, it is well understood that Mars is a cold, dry, and geologically dead planet. However, billions of years ago when it was still young, the planet boasted a denser atmosphere and had liquid water on its surface. Millions of years ago, it also experienced a significant amount of volcanic activity, which resulted in the formation of it’s massive features – like Olympus Mons, the largest volcano in the Solar System.

Until recently, scientists have understood that Martian volcanic activity has been driven by sources other than tectonic movement, which the planet has been devoid of for billions of years. However, after conducting a study of Martian rock samples, a team of researchers from the UK and United States concluded that eons ago, Mars was more volcanically active than previously thought.

Their study, titled “Taking the Pulse of Mars via Dating of a Plume-fed Volcano“, recently appeared in the scientific journal Nature Communications. Led by Benjamin Cohen, a researcher with the Scottish Universities Environmental Research Center (SUERC) and the School of Geographical and Earth Sciences at the University of Glasgow, the team conducted an analysis of Mars’ volcanic past using samples of Martian meteorites.

*Asteroid impacts on Mars have sent samples of Martian rock to Earth in the form of meteorites. Credit: geol.umd.edu*

On Earth, the majority of volcanism occurs as a result of plate tectonics, which are driven by convection in the Earth’s mantle. But on Mars, the majority of volcanic activity is the result of mantle plumes, which are highly-localized upwellings of magma that rise from deep within the mantle. This is due to the fact that Mars’ surface has remained static and cool for the past few billion years.

Because of this, Martian volcanoes (though similar in morophology to shield volcanoes on Earth), grow to much larger sizes than those on Earth. Olympus Mons, for example, is not only the largest shield volcano on Mars, but the largest in the Solar System. Whereas the tallest mountain on Earth – Mt. Everest – is 8,848 m (29,029 ft) in height, Olympus Mons stands some 22 km (13.6 mi or 72,000 ft) tall.

For the sake of their study, Dr. Cohen and his colleagues used radioscopic dating techniques, which are commonly used to determine the age and eruption rate of volcanoes on Earth. However, such techniques have not been previously used for shield volcanoes on Mars. As a result, the team’s study of Martian meteorite samples was the first detailed analysis of growth rates in Martian volcanoes.

The six samples they examined are known as nakhlites, a class of Martian meteorite that formed from basaltic magma roughly 1.3 billion years ago. These came to Earth roughly 11 million years ago after being were blasted from the face of Mars by an impact event. By conducting an analysis of Martian meteorites, the team was able to uncover about 90 million years’ worth of new information about Mars’ volcanic past.

Color Mosaic of Olympus Mons on Mars — Color mosaic of Mars’ greatest mountain, Olympus Mons, viewed from orbit. Credit NASA/JPL

As Dr. Cohen explained in a University of Glasgow press release:

“We know from previous studies that the nakhlite meteorites are volcanic rocks, and the development of age-dating techniques in recent years made the nakhlites perfect candidates to help us learn more about volcanoes on Mars.”

The first step was to demonstrate that the rock samples were indeed Martian in origin, which the team confirmed by measuring their exposure to cosmogenic radiation. From this, they determined that the rocks were expelled from the Martian surface 11 million years ago, most likely as a result of an impact event on the Martian surface. They then applied a high-precision radioscopic technique known as ⁴⁰Ar/³⁹Ar dating.

This consisted of using a noble gas mass spectromomer to measure the amount of argon built up in the samples, which is the result of the natural radioactive decay of potassium. From this, they were able to obtain 90 million years’ worth of new information about the Martian surface. The results of their analysis indicated that there are significant differences in volcanic history between the Earth and Mars. As Dr. Cohen explained:

“We found that the nakhlites formed from at least four eruptions over the course of 90 million years. This is a very long time for a volcano, and much longer than the duration of terrestrial volcanoes, which are typically only active for a few million years. And this is only scratching the surface of the volcano, as only a very small amount of rock would have been ejected by the impact crater – so the volcano must have been active for much longer.”

*A triple crater in Elysium Planitia on Mars. Credit: NASA/JPL/University of Arizona*

In addition, the team was also able to narrow down which volcanoes their rock samples came from. Previous studies conducted by NASA revealed several candidates for the possible nakhlite source crater. However, only one of the locations matched their results in terms of the age of the volcanic eruptions and the impact that would have ejected the samples into space.

This particular crater (which is currently unnamed) is located in the volcanic plains known as Elysium Planitia, roughly 900 km (560 mi) away from summit of the Elysium Mons volcano – which stands 12.6 km (7.8 mi) tall. It is also located about 2000 km (1243 mi) north of where the NASA Curiosity rover currently is. As Cohen explained, NASA has some wonderfully detailed satellite images of this particular crater.

“It is 6.5 km wide, and has preserved ejecta rays of debris,” he said. “And we were able to see multiple horizontal bands on the crater walls – which indicating the rocks form layers, with each layer interpreted as a separate lava flow. This study has been able to provide a clearer picture into the history of the nakhlite meteorites, and in turn the largest volcanoes in the solar system.”

In the future, sample return and crewed missions to Mars are sure to clear up this picture even further. Given that Mars, like Earth, is a terrestrial planet, knowing all we can about its geological history will ultimately improve our understanding of how the rocky planets of the Solar System formed. In short, the more we know about Mars’ volcanic history, the most we will be able to learn about the Solar System’s formation and evolution.

Further Reading: University of Glasgow, Nature Communications

October 10, 2017October 11, 2017 by Ken Kremer

SpaceX Sets Oct. 11 Sunset Blastoff of SES-11 North American UHD TV Sat on Used Falcon 9 Rocket: Watch Live

KENNEDY SPACE CENTER, FL – SpaceX is all set for a sunset blastoff Wednesday, Oct. 11 of the commercial SES-11/EchoStar 105 Ultra High Definition (UHD) TV satellite serving North America on a ‘used’ Falcon 9 booster from the Florida Space Coast – that is also targeted to re-land a second time on an sea going platform off shore in the Atlantic.

Spectators should enjoy a spectacular view of the SpaceX Falcon 9 dinnertime launch with a forecast of extremely favorable weather conditions. This comes on the heels of multiple deluges of torrential rain that twice scrubbed last week’s launch of a United Launch Alliance V carrying a USAF spy satellite.

The private SES-11/EchoStar 105 communications satellite mission will launch on a ‘flight-proven’ booster and is slated for a dinnertime liftoff on Oct. 11 at 6:53 p.m. EDT from seaside Launch Complex 39A at NASA’s Kennedy Space Center in Florida, carrying the SES-11.

All systems are GO at L Minus 1 Day!

“#EchoStar105 is targeted for launch Oct. 11 from launch Complex 39A at NASA’s Kennedy Space Center in Florida-launch window 6:53-8:53 PM EDT,” EchoStar tweeted today.

“Getting Echostar-105/#SES11 ready for launch!” SES tweeted further.

SES-11/EchoStar 105 commercial telecomsat. Credit: SES

If all goes well this will be the second launch for SpaceX this week following Monday’s Falcon 9 launch from Vandenberg AFB, Ca carrying 10 Iridium-NEXT satellites to orbit – and a record setting 15th of 2017!

EchoStar 105/SES-11 is a high-powered hybrid Ku and C-band communications satellite launching as a dual-mission satellite for US-based operator EchoStar and Luxembourg-based operator SES.

The used two stage 229-foot-tall (70-meter) Falcon 9 rocket was rolled out to pad 39A today, erected to vertical launch position and is now poised for liftoff Wednesday.

It will launch the two and a half ton EchoStar 105/SES-11 to geostationary orbit some 22,000 miles (36,000 kilometers) above the equator.

SpaceX will also attempt to recover this recycled Falcon 9 first stage booster again by soft landing on a droneship platform prepositioned hundreds of miles off shore in the Atlantic Ocean – some 8 minutes after blastoff.

Spectacular weather is expected Wednesday for space enthusiasts gathering in local regional hotels after traveling here from across the globe.

Playalinda Beach is among the best places to witness the launch from – while surfing the waves too – if you’re in the area.

You can watch the launch live on a SpaceX dedicated webcast starting about 10 minutes prior to the 6:53 pm EDT or 10:53 pm UTC liftoff time.

Watch the SpaceX broadcast live at: SpaceX.com/webcast

The two hour long launch window closes at 8:53 p.m. EDT.

The weather outlook is currently exceptional along the Florida Space Coast with a 90% chance of favorable conditions at launch time according to U.S. Air Force meteorologists with the 45th Space Wing Weather Squadron at Patrick Air Force Base. The primary concerns on Oct. 11 are only for Cumulus Clouds.

The odds remain high at 90% favorable for the 24 hour scrub turnaround day on Oct. 12.

Reflown SpaceX Falcon 9 soars to orbit with SES-10 telecomsat from historic Launch Complex 39A at NASA’s Kennedy Space Center in Florida at 6:27 p.m. EDT on March 30, 2017. Credit: Ken Kremer/Kenkremer.com

The 45th Space Wing forecast is also favorable for the landing recovery area through Thursday “when a low pressure system may move into the area, increasing winds and seas. This low will migrate west and possibly impact Florida by the weekend.”

After the 156 foot tall first stage booster complets its primary mission task, SpaceX engineers seek to guide it to a second landing on the tiny OCISLY drone ship for a soft touchdown some eight and a half minutes after liftoff.

World’s first reflown rocket booster – the SpaceX Falcon 9 first stage – sails back into Port Canaveral, FL just before sunrise atop OCISLY droneship on which it landed 9 minutes after March 30, 2017 liftoff from KSC with SES-10 telecomsat – as seen entering channels mouth trailing a flock of birds from Jetty Park pier on April 4, 2017. Credit: Ken Kremer/Kenkremer.com

OCISLY or “Of Course I Still Love You” left Port Canaveral several days ahead of the planned Oct. 11 launch and is prepositioned in the Atlantic Ocean some 400 miles (600 km) off the US East coast, just waiting for the boosters 2nd approach and pinpoint propulsive soft landing.

The EchoStar 105/SES-11 spacecraft was built by Airbus and shipped from the Airbus facilities in Toulouse, France to Cape Canaveral, FL for flight processing.

The satellite is scheduled to be deployed approximately 36 minutes after liftoff.

The path to launch was cleared following last weeks successful static fire test of the first stage engines Falcon 9.

During the Oct. 2 static fire test, the rocket’s first and second stages were fueled with liquid oxygen and RP-1 propellants like an actual launch, and a simulated countdown was carried out to the point of a brief engine ignition.

The hold down engine test with the erected rocket involved the ignition of all nine Merlin 1D first stage engines generating some 1.7 million pounds of thrust at pad 39A while the two stage rocket was restrained on the pad – minus the expensive payload.

SpaceX conducts successful static hot fire test of recycled Falcon 9 at Launch Complex 39A at the Kennedy Space Center on 2 Oct 2017 as a gator gazes from Playalinda waterways, FL. Liftoff is slated for 7 Oct 2017 with SES-11/EchoStar 105 telecommunications comsat. Credit: Ken Kremer/Kenkremer.com

Following the hot fire test, the rocket was rolled back to the processing hangar located just outside the pad perimeter fence.

The 5,200 kg (11,500 pounds) satellite encapsulated inside the payload fairing was then integrated with the Falcon 9 rocket.

Mating of SES-11/EchoStar 105 commercial telecomsat. Credit: SES

This is only the third recycled SpaceX Falcon 9 ever to be launched from Pad 39A.

SES was the first company to ever fly a payload on a ‘flight-proven’ Falcon 9. The SES-10 satellite lifted off successfully this spring on March 30, 2017.

The second reflown booster successfully launched the BulgariaSat-1 a few months later.

This Falcon 9 booster previously flew on SpaceX’s 10th resupply mission to the International Space Station (CRS-10) in February of this year and made a ground landing at the Cape at LZ-1.

Pad 39A has been repurposed by SpaceX from its days as a NASA shuttle launch pad.

The last SpaceX Falcon 9 launch from KSC took place on Sept. 7 carrying the USAF X-37B military space plane to orbit just ahead of Hurricane Irma.

USAF X-37B military mini-shuttle lifts off on classified OTV-5 mission at 10 a.m. EDT Sept. 7, 2017 on a SpaceX Falcon 9 rocket from Launch Complex 39A at the Kennedy Space Center. Credit: Ken Kremer/kenkremer.com

Watch for Ken’s continuing onsite coverage of SpaceX SES-11, ULA NROL-52 and NASA and space mission reports direct from the Kennedy Space Center and Cape Canaveral Air Force Station, Florida.

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

Ken Kremer

Mission patch for the SES-11/EchoStar 105 communications satellite launch by SpaceX. Credit: SpaceX

SpaceX Falcon 9 recycled rocket carrying SES-10 telecomsat raised erect atop Launch Complex 39A at the Kennedy Space Center as seen from inside the pad ahead of liftoff on 30 Mar 2017 on world’s first reflight of an orbit class rocket. Credit: Ken Kremer/Kenkremer.com

October 9, 2017December 6, 2017 by Susie Murph

Astronomy Cast Ep. 460: Earth from Afar: Remote Sensing

The space age has given us the ability to look at every corner of the globe in every wavelength. It’s revolutionized our ability to predict the weather, keep track of environmental damage, and watch the world change. Today we look at what missions and technologies give us the ability to watch our world from afar.

We usually record Astronomy Cast every Friday at 1:30 pm PDT / 4:30 pm EDT/ 20:30 PM UTC (8:30 GMT). You can watch us live on AstronomyCast.com, or the AstronomyCast YouTube page.

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