Weekly Space Hangout – Nov 8, 2017: This Week in Musk, and More!

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)

Announcements:

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Proxima Centauri has a Cold Dust Belt that Could Indicate Even More Planets

This artist’s impression shows how the newly discovered belts of dust around the closest star to the Solar System, Proxima Centauri, may look. Credit: ESO/M. Kornmesser

Proxima Centauri, in addition to being the closest star system to our own, is also the home of the closest exoplanet to Earth. The existence of this planet, Proxima b, was first announced in August of 2016 and then confirmed later that month. The news was met with a great deal of excitement, and a fair of skepticism, as numerous studies followed t were dedicated to determining if this planet could in fact be habitable.

Another important question has been whether or not Proxima Centauri could have any more objects orbiting it. According to a recent study by an international team of astronomers, Proxima Centauri is also home to a belt of cold dust and debris that is similar to the Main Asteroid Belt and Kuiper Belt in our Solar System. The existence of this dusty belt could indicate the presence of more planets in this star system.

The study, titled “ALMA Discovery of Dust Belts Around Proxima Centauri“, recently appeared online and is scheduled to appear in the Monthly Notices of the Astronomical Society. The study was led by Guillem Anglada from the Astrophysical Institute of Andalusia (CSIS), and included members from the Institute of Space Sciences (IEEC), the European Southern Observatory (ESO), the Joint ALMA Observatory, and multiple universities.

View of the Atacama Large Millimeter/submillimeter Array (ALMA) site in the Atacama Desert of northern Chile. Credit: A. Marinkovic/X-Cam/ALMA (ESO/NAOJ/NRAO)

For their study, the team relied on data obtained by the Atacama Large Millimeter/submillimter Array (ALMA) at the ALMA Observatory in Chile. These observations revealed the glow of a cold dust belt that is roughly 1 to 4 AUs from Proxima Centauri – one to four times the distance between the Earth and the Sun. This puts it significantly further out than Proxima b, which orbits its sun at a distance of 0.0485 AU (~5% of Earth’s distance from the Sun).

Dust belts are essentially the leftover material that did not form into larger bodies withing a star system. The particles of rock and ice in these belts vary in size from being smaller than a millimeter across to asteroids that are many kilometers in diameter. Based on their observations, the team estimated that the belt in Proxima Centauri has a total mass that is about one-hundredth the mass of Earth.

The team also estimated that this belt experiences temperatures of about 43 K (-230°C; -382 °F), making it as cold as the Kuiper Belt. As Dr. Anglada explained the significance of these findings in a recent ESO press release:

“The dust around Proxima is important because, following the discovery of the terrestrial planet Proxima b, it’s the first indication of the presence of an elaborate planetary system, and not just a single planet, around the star closest to our Sun.”

This infographic compares the orbit of the planet around Proxima Centauri (Proxima b) with the same region of the Solar System. Credit: ESO

The ALMA data also provided indications that Proxima Centauri might also have another belt located about ten times further out. In other words, Proxima Centauri may have two belts, just like our Solar System. If confirmed, this could indicate that this neighboring star also has a system of planets that fall within and between belts of unconsolidated material, which in turn is leftover from the early days of planet formation. As Dr. Anglada explained:

“This result suggests that Proxima Centauri may have a multiple planet system with a rich history of interactions that resulted in the formation of a dust belt. Further study may also provide information that might point to the locations of as yet unidentified additional planets.”

The very cold environment of this outer belt could also have some interesting implications, since its parent star is much dimmer than our own. Pedro Amado, who also hails from the Astrophysical Institute of Andalusia, was similarly enthusiastic about these findings. As he indicated, they are just the beginning of what is sure to be a long process of discovery about this system.

“These first results show that ALMA can detect dust structures orbiting around Proxima,” he said. “Further observations will give us a more detailed picture of Proxima’s planetary system. In combination with the study of protoplanetary discs around young stars, many of the details of the processes that led to the formation of the Earth and the Solar System about 4600 million years ago will be unveiled. What we are seeing now is just the appetiser compared to what is coming!”

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

This study is also likely to be of interest to those planning on conducting direct observations of the Alpha Centauri system, such as Project Blue. In the coming years, they hope to deploy a space telescope that will observe Alpha Centauri directly to study any exoplanets it may have. With a slight adjustment, this telescope could also take a gander at Proxima Centauri and aid in the hunt for a system of planets there.

And then there’s Breakthrough Starshot, the first proposed interstellar voyage which hopes to send a laser sail-driven nanocraft to Alpha Centauri in the coming decades. Recently, the scientists behind Starshot discussed the possibility of extending the mission to include a stopover in Proxima Centauri. Before such a mission can take place, the planners need to know what kind of dusty environment awaits it.

And of course, future studies will benefit from the deployment of next-generation instruments, like the James Webb Space Telescope (scheduled for launch in 2019) and the ESO’s Extremely Large Telescope (ELT) – which is expected to collect its first light in 2024.

Further Reading: ESO, arXiv

They Just Began Casting the Giant Magellan Telescope’s 5th Mirror. What a Monster Job.

The fifth mirror for the GMT's 7 segment primary mirror is being cast at the Richard F. Caris Mirror Laboratory at the University of Arizona. In this image, a worker at the lab places the last piece of glass for mirror 5. Image: Giant Magellan Telescope Organization

The fifth mirror for the Giant Magellan Telescope (GMT) is now being cast, according to an announcement from the Giant Magellan Telescope Organization (GMTO), the body behind the project. The GMT is a ground-breaking segmented telescope consisting of 7 gigantic mirrors, and is being built at the Las Campanas Observatory, in Atacama, Chile.

The mirrors for the GMT are being cast at the Richard F. Caris Mirror Laboratory, at the University of Arizona. This lab is the world centre when it comes to building large mirrors for telescopes. But in a lab known for ground-breaking, precision manufacturing, the GMT’s mirrors are pushing the engineering to its limits.

This illustration shows what the Giant Magellan Telescope will look like when it comes online. The fifth of its seven mirror segments is being cast now. Each of the segments is a 20 ton piece of glass. Image: Giant Magellan
This illustration shows what the Giant Magellan Telescope will look like when it comes online. The fifth of its seven mirror segments is being cast now. Each of the segments is a 20 ton piece of glass. Image: Giant Magellan Telescope – GMTO Corporation

Seven separate mirrors, each the same size (8.4 meters,) will make up the GMT’s primary mirror. One mirror will be in the centre, and six will be arranged in a circle around it. Each one of these mirrors is a 20 ton glass behemoth, and each one is cast separately. Once the seven are manufactured (and one extra, just in case) they will be assembled at the observatory site.

The result will be an optical, light-gathering surface almost 24.5 meters (80 ft.) in diameter. That is an enormous telescope, and it’s taking extremely precise engineering and manufacturing to build these mirrors.

The glass for the mirrors is custom-manufactured, low-expansion glass from Japan. This glass comes as blocks, and each mirror requires exactly 17,481 kg of these glass blocks. A custom built furnace and mold heats the glass to 1165°C (2129°F) for several hours. The glass liquefies and flows into the mold. During this time, the mold is rotated at up to 5 rpm. Then the rotation is slowed, and for several months the glass cools in the mold.

After lengthy cooling, the glass can be polished. The tolerances for the mirrors, and the final shape they must take, requires very careful, extremely accurate polishing. The first mirror was cast in 2005, and in 2011 it was still being polished.

The mirrors for the GMT are not flat; they’re described as “potato chips.” They’re aspherical and parabaloidal. They have to be surface polished to an accuracy of 25 nanometers, which is a fraction of the wavelength of light.

Precision manufacturing is at the heart of the Giant Magellan Telescope. The surface of each mirror must be polished to within a fraction of the wavelength of light. Image: Giant Magellan Telescope Organization
Precision manufacturing is at the heart of the Giant Magellan Telescope. The surface of each mirror must be polished to within a fraction of the wavelength of light. Image: Giant Magellan Telescope Organization

“Casting the mirrors for the Giant Magellan Telescope is a huge undertaking, and we are very proud of the UA’s leading role creating this new resource for scientific discovery. The GMT partnership and Caris Mirror Lab are outstanding examples of how we can tackle complex challenges with innovative solutions,” said UA President Robert C. Robbins. “The University of Arizona has such an amazing tradition of excellence in space exploration, and I have been constantly impressed by the things our faculty, staff, and students in astronomy and space sciences can accomplish.”

Mirror construction for the GMT is a multi-stage process. The first mirror was completed several years ago and is in storage. Three others are in various stages of grinding and polishing. The glass for mirror 6 is in storage awaiting casting, and the glass for mirror 7 is on order from Japan.

Once completed, the GMT will be situated in Atacama, at the Las Campanas Observatory, where high-elevation and clear skies make for excellent seeing conditions. First light is planned for the mid 2020’s.

When the mirrors for the GMT are completed, they are transported in a special container with shock absorbers and insulation. In this image, the first completed mirror is moved from the Caris Mirror Lab to storage several miles away. Image: GMTO Corp.
When the mirrors for the GMT are completed, they are transported in a special container with shock absorbers and insulation. In this image, the first completed mirror is moved from the Caris Mirror Lab to storage several miles away. Image: GMTO Corp.

The GMT will be largest telescope in existence, at least until the Thirty Meter Telescope and the European Extremely Large Telescope supersede it.

“Creating the largest telescope in history is a monumental endeavor, and the GMT will be among the largest privately-funded scientific initiatives to date,” said Taft Armandroff, Professor of Astronomy and Director of the McDonald Observatory at The University of Texas at Austin, and Vice-Chair of the GMTO Corporation Board of Directors. “With this next milestone, and with the leadership, technical, financial and scientific prowess of the members of the GMTO partnership, we continue on the path to the completion of this great observatory.”

The power of the GMT will allow it to directly image extra-solar planets. That alone is enough to get anyone excited. But the GMT will also study things like the formation of stars, planets, and disks; the assembly and evolution of galaxies; fundamental physics; and first light and re-ionization.

The Giant Magellan Telescope is one of the world’s Super Telescopes that we covered in this series of articles. The Super Telescopes include the:

  • Giant Magellan Telescope
  • James Webb Space Telescope
  • Thirty Meter Telescope
  • European Extremely Large Telescope
  • Large Synoptic Survey Telescope
  • Wide Field Infrared Survey Telescope

You can also watch our videos on the Super Telescopes: Part 1: Ground Telescopes, and Part 2: Space Telescopes.

New Study Says Enceladus has had an Internal Ocean for Billions of Years

Cutaway showing the interior of Saturn's moon Enceladus. Credit: ESA

When the Cassini mission arrived in the Saturn system in 2004, it discovered something rather unexpected in Enceladus’ southern hemisphere. From hundreds of fissures located in the polar region, plumes of water and organic molecules were spotted periodically spewing forth. This was the first indication that Saturn’s moon may have an interior ocean caused by hydrothermal activity near the core-mantle boundary.

According to a new study based on Cassini data, which it obtained before diving into Saturn’s atmosphere on September 15th, this activity may have been going on for some time. In fact, the study team concluded that if the moon’s core is porous enough, it could have generated enough heat to maintain an interior ocean for billions of years. This study is the most encouraging indication yet that the interior of Enceladus could support life.

The study, titled “Powering prolonged hydrothermal activity inside Enceladus“, recently appeared in the journal Nature Astronomy. The study was led by Gaël Choblet, a researcher with the Planetary and Geodynamic Laboratory at the University of Nantes, and included members from NASA’s Jet Propulsion Laboratory, Charles University, and the Institute of Earth Sciences and the Geo- and Cosmochemistry Laboratory at the University of Heidelberg.

Artist’s rendering of possible hydrothermal activity that may be taking place on and under the seafloor of Enceladus. Credit: NASA/JPL

Prior to the Cassini mission’s many flybys of Enceladus, scientists believed this moon’s surface was composed of solid ice. It was only after noticing the plume activity that they came to realize that it had water jets that extended all the way down to a warm-water ocean in its interior. From the data obtained by Cassini, scientists were even able to make educated guesses of where this internal ocean lay.

All told, Enceladus is a relatively small moon, measuring some 500 km (311 mi) in diameter. Based on gravity measurements performed by Cassini, its interior ocean is believed to lie beneath an icy outer surface at depths of 20 to 25 km (12.4 to 15.5 mi). However, this surface ice thins to about 1 to 5 km (0.6 to 3.1 mi) over the southern polar region, where the jets of water and icy particles jet through fissures.

Based on the way Enceladus orbits Saturn with a certain wobble (aka. libration), scientists have been able to make estimates of the ocean’s depth, which they place at 26 to 31 km (16 to 19 mi). All of this surrounds a core which is believed to be composed of silicate minerals and metal, but which is also porous. Despite all these findings, the source of the interior heat has remained something of an open question.

This mechanism would have to be active when the moon formed billions of years ago and is still active today (as evidenced by the current plume activity). As Dr. Choblet explained in an ESA press statement:

“Where Enceladus gets the sustained power to remain active has always been a bit of mystery, but we’ve now considered in greater detail how the structure and composition of the moon’s rocky core could play a key role in generating the necessary energy.”

Gravity measurements by NASA’s Cassini spacecraft and Deep Space Network suggest that Saturn’s moon Enceladus, which has jets of water vapor and ice gushing from its south pole, also harbors a large interior ocean beneath an ice shell, as this illustration depicts. Credit: NASA/JPL-Caltech

For years, scientists have speculated that tidal forces caused by Saturn’s gravitational influence are responsible for Enceladus’ internal heating. The way Saturn pushes and pulls the moon as it follows an elliptical path around the planet is also believed to be what causes Enceladus’ icy shell to deform, causing the fissures around the southern polar region. These same mechanisms are believed to be what is responsible for Europa’s interior warm-water ocean.

However, the energy produced by tidal friction in the ice is too weak to counterbalance the heat loss seen from the ocean. At the rate Enceladus’ ocean is losing energy to space, the entire moon would freeze solid within 30 million years. Similarly, the natural decay of radioactive elements within the core (which has been suggested for other moons as well) is also about 100 times too weak to explain Enceladus interior and plume activity.

To address this, Dr. Choblet and his team conducted simulations of Enceladus’ core to determine what kind of conditions could allow for tidal heating over billions of years. As they state in their study:

“In absence of direct constraints on the mechanical properties of Enceladus’ core, we consider a wide range of parameters to characterize the rate of tidal friction and the efficiency of water transport by porous flow. The unconsolidated core of Enceladus can be viewed as a highly granular/fragmented material, in which tidal deformation is likely to be associated with intergranular friction during fragment rearrangements.”
Artist rendering showing an interior cross-section of the crust of Enceladus, which shows how hydrothermal activity may be causing the plumes of water at the moon’s surface.Credits: NASA-GSFC/SVS, NASA/JPL-Caltech/Southwest Research Institute

What they found was that in order for the Cassini observations to be borne out, Enceladus’ core would need to be made of unconsolidated, easily deformable, porous rock. This core could be easily permeated by liquid water, which would seep into the core and gradually heated through tidal friction between sliding rock fragments. Once this water was sufficiently heated, it would rise upwards because of temperature differences with its surroundings.

This process ultimately transfers heat to the interior ocean in narrow plumes which rise to the meet Enceladus’ icy shell. Once there, it causes the surface ice to melt and forming fissures through which jets reach  into space, spewing water, ice particles and hydrated minerals that replenish Saturn’s E-Ring. All of this is consistent with the observations made by Cassini, and is sustainable from a geophysical point of view.

In other words, this study is able to show that action in Enceladus’ core could produce the necessary heating to maintain a global ocean and produce plume activity. Since this action is a result of the core’s structure and tidal interaction with Saturn, it is perfectly logical that it has been taking place for billions of years. So beyond providing the first coherent explanation for Enceladus’ plume activity, this study is also a strong indication of habitability.

As scientists have come to understand, life takes a long time to get going. On Earth, it is estimated that the first microorganisms arose after 500 million years, and hydrothermal vents are believed to have played a key role in that process. It took another 2.5 billion years for the first multi-cellular life to evolve, and land-based plants and animals have only been around for the past 500 million years.

Knowing that moons like Enceladus – which has the necessary chemistry to support for life – has also had the necessary energy for billions of years is therefore very encouraging. One can only imagine what we will find once future missions begin inspecting its plumes more closely!

Further Reading: ESA, Nature Astronomy

Astronomy Cast Ep. 464: Why the Hype over an Exorock?

Astronomers this week announced that they had discovered an asteroid or comet on a trajectory that brought it from outside the Solar System? Is this the first case of an object from deep space? And what can we learn from this discovery?

We usually record Astronomy Cast every Friday at 3:00 pm EST / 12:00 pm PST / 20:00 PM UTC. You can watch us live on AstronomyCast.com, or the AstronomyCast YouTube page.

Visit the Astronomy Cast Page to subscribe to the audio podcast!

If you would like to support Astronomy Cast, please visit our page at Patreon here – https://www.patreon.com/astronomycast. We greatly appreciate your support!

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!

Messier 59 – the NGC 4621 Elliptical Galaxy

Messier 60, Messier 59 and Messier 58. Credit: Wikisky

Welcome back to Messier Monday! Today, we continue in our tribute to our dear friend, Tammy Plotner, by looking at the spiral galaxy known as Messier 59.

In the 18th century, while searching the night sky for comets, French astronomer Charles Messier kept noting the presence of fixed, diffuse objects he initially mistook for comets. In time, he would come to compile a list of approximately 100 of these objects, hoping to prevent other astronomers from making the same mistake. This list – known as the Messier Catalog – would go on to become one of the most influential catalogs of Deep Sky Objects.

One of these objects is the elliptical galaxy known as Messier 59 (aka. NGC 4621). This galaxy is located approximately 60 million light-years from Earth in the direction of the southern Virgo constellation. Sitting just a few degrees away Messier 60, and bordered at a distance by Messier 58, this galaxy is visible using smaller instruments, but is best observed using a larger telescope.

Atlas image of Messier 59 obtained by the Two micron All Sky Survey (2MASS). Credit: 2MASS/NASA/UMass

Description:

Located about 60 million light years away and spanning about 90 million light years of space, but what exactly is its type? Says Takao Mizuno (et al) in their 1996 study:

“We decomposed two-dimensionally an elliptical galaxy, NGC 4621, which shows deviations from the brightness distribution law. We have found that its brightness distribution can be reproduced by three components possessing constant ellipticities of the residuals in the circular region of radius. The component obeying the aw has 62% of the total light, and, hence, is the main body of this elliptical galaxy.” So it might not be the biggest or the brightest of the group, but it is home to nearly 2000 globular clusters. This isn’t news when it comes to this galaxy type, but what is news is how they rotate… the wrong way!

“We present adaptive optics assisted OASIS integral field spectrography of the S0 galaxy NGC 4621. Two-dimensional stellar kinematical maps (mean velocity and dispersion) reveal the presence of a 60 pc diameter counter-rotating core (CRC), the smallest observed to date.” says Fabien Wernli (et al), “The OASIS data also suggests that the kinematic center of the CRC is slightly offset from the center of the outer isophotes. This seems to be confirmed by archival HST/STIS data. We also present the HST/WFPC2 V-I colour map, which exhibits a central elongated red structure, also slightly off-centered in the same direction as the kinematic centre. Although the stellar velocities are reasonably fitted, including the region of the counter-rotating core, significant discrepancies between the model and the observations demonstrate the need for a more general model.”

What could account for such unusual behavior? Try a quiet black hole! As J. M. Wrobel (et al) indicated in their 2008 study:

“The nearby elliptical galaxies NGC 4621 and NGC 4697 each host a supermassive black hole. Analysis of archival Chandra data and new NRAO Very Large Array data shows that each galaxy contains a low-luminosity active galactic nucleus (LLAGN), identified as a faint, hard X-ray source that is astrometrically coincident with a faint 8.5-GHz source. The black holes energizing these LLAGNs have Eddington ratios placing them in the so-called quiescent regime. The emission from these quiescent black holes is radio-loud, suggesting the presence of a radio outflow. Also, application of the radio-X-ray-mass relation from Yuan & Cui for quiescent black holes predicts the observed radio luminosities to within a factor of a few. Significantly, that relation invokes X-ray emission from the outflow rather than from an accretion flow. The faint, but detectable, emission from these two massive black holes is therefore consistent with being outflow-dominated.”

The M59 spiral galaxy. Credit: NOAO

History of Observation:

Both M59 and neighboring M60 were discovered on April 11, 1779 by Johann Gottfried Koehler who wrote: “Two very small nebulae, hardly visible in a 3-foot telescope: The one above the other.” Charles Messier would independently recover it four days later and state in his notes:

“Nebula in Virgo and in the neighborhood of the preceding [M58], on the parallel of epsilon [Virginis], which has served for its [position] determination: it is of the same light as the above, equally faint. M. Messier reported it on the Chart of the Comet of 1779.”

While both William and John Herschel would also observe it, it sometimes confounds me that they didn’t seem to notice all the other galaxies around it! Fortunately for historic record, Admiral Smyth did:

“A fine field is exhibited under the eye-piece, which magnifies 93 times, just as this object [M60 with NGC 4647] enters, because the bright little nebula 59 M. is quitting the np [north preceding, NW] verge, and another small one is seen in the upper part, H. 1402 [NGC 4638]: in fact, four nebulae at once.”

Locating Messier 58:

M59 is a telescope-only object and requires patience to find. Because the Virgo Galaxy field contains so many galaxies which can easily be misidentified, it is sometimes easier to “hop” from one galaxy to the next. In this case, we need to start by locating bright Vindemiatrix (Epsilon Virginis) almost due east of Denebola. Then starhop four and a half degrees west and a shade north of Epsilon to locate one of the largest elliptical galaxies presently known – M60.

The location of M59, which sits between M58 and M60 in the direction of the Virgo constellation. Credit: IAU

At a little brighter than magnitude 9, this galaxy could be spotted with binoculars, but stick with your telescope. In the same low power field (depending on aperture size) you may also note faint NGC 4647 which only appears to be interacting with M60. Also in the field to the west (the direction of drift) is the Messier we’re looking for, bright cored elliptical galaxy M59.

In a smaller telescope, do not expect to see much. What will appear at low power is a tiny egg-shaped patch of contrast change with a brighter center. As aperture increases, a sharper nucleus will begin to appear as you move into the 4-6″ size range at dark sky locations, but elliptical galaxies do not show details. As with all galaxies, dark skies are a must!

Enjoy your journey around the Virgo Galaxy Field!

Object Name: Messier 59
Alternative Designations: M59, NGC 4621
Object Type: E5 Galaxy
Constellation: Virgo
Right Ascension: 12 : 42.0 (h:m)
Declination: +11 : 39 (deg:m)
Distance: 60000 (kly)
Visual Brightness: 9.6 (mag)
Apparent Dimension: 5×3.5 (arc min)

We have written many interesting articles about Messier Objects here at Universe Today. Here’s Tammy Plotner’s Introduction to the Messier ObjectsM1 – The Crab 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:

Cutting-Edge Astronomy Confirms Most Ancient Galaxy to Date

This illustration shows how gravitational lensing works. The gravity of a large galaxy cluster is so strong, it bends, brightens and distorts the light of distant galaxies behind it. The scale has been greatly exaggerated; in reality, the distant galaxy is much further away and much smaller. Credit: NASA, ESA, L. Calcada

Since the deployment of the Hubble Space Telescope, astronomers have been able to look deeper into the cosmic web than ever before. The farther they’ve looked, the deeper back in time they are able to see, and thus learn what the Universe looked like billions of years ago. With the deployment of other cutting-edge telescopes and observatories, scientists have been able to learn a great deal more about the history and evolution of the cosmos.

Most recently, an international team of astronomers using the Gemini North Telescope in Hawaii were able to spot a spiral galaxy located 11 billion light years away. Thanks to a new technique that combined gravitational lensing and spectrography, they were able to see an object that existed just 2.6 billion years after the Big Bang. This makes this spiral galaxy, known as A1689B11, the oldest and most distant spiral galaxy spotted to date.

The study which details the team’s findings, titled “The most ancient spiral galaxy: a 2.6-Gyr-old disk with a tranquil velocity field“, recently appeared in The Astrophysical Journal. The team consisted of members from the Swinburne University of Technology, the Australian Research Council Center of Excellence in All Sky Astrophysics in 3D (ASTRO 3D), the University of Lyon, Princeton University, and the Racah Institute of Physics at The Hebrew University in Jerusalem.

Spiral galaxy A1689B11 sits behind a massive cluster of galaxies that acts as a lens, producing two magnified images of the spiral galaxy in different positions in the sky. Credit: James Josephides

Together, the team relied on the gravitational lensing technique to spot A1689B11. This technique has become a mainstay for astronomers, and involves using a large object (like a galaxy cluster) to bend and magnify the light of a galaxy located behind it. As Dr. Tiantian Yuan, a Swinburne astronomer and the lead author on the research study, explained in a Swinburne press statement:

“This technique allows us to study ancient galaxies in high resolution with unprecedented detail. We are able to look 11 billion years back in time and directly witness the formation of the first, primitive spiral arms of a galaxy.”

They then used the Near-infrared Integral Field Spectrograph (NIFS) on the Gemini North telescope to verify the structure and nature of this spiral galaxy. This instrument was built Peter McGregor of The Australian National University (ANU), which now is responsible for maintaining it. Thanks to this latest discovery, astronomers now have some additional clues as to how galaxies took on the forms that we are familiar with today.

Based on the classification scheme developed by famed astronomer Edwin Hubble (the “Hubble Sequence“), galaxies are divides into 3 broad classes based on their shapes – ellipticals, lenticulars and spirals – with a fourth category reserved for “irregularly-shaped” galaxies. In accordance with this scheme, galaxies start out as elliptical structures before branching off to become spiraled, lenticular, or irregular.

A figure illustrating the Hubble sequence, showing elliptical galaxies (left) and evolving to fit the three broad categories (right) of ellipticals, lenticulars and spirals. Credit: Ville Koistinen

As such, the discovery of such an ancient spiral galaxy is crucial to determining when and how the earliest galaxies began changing from being elliptical to taking on their modern forms. As Dr Renyue Cen, an astronomer from Princeton University and a co-author on the study, says:

“Studying ancient spirals like A1689B11 is a key to unlocking the mystery of how and when the Hubble sequence emerges. Spiral galaxies are exceptionally rare in the early Universe, and this discovery opens the door to investigating how galaxies transition from highly chaotic, turbulent discs to tranquil, thin discs like those of our own Milky Way galaxy.”

On top of that, this study showed that the A1689B11 spiral galaxy has some surprising features which could also help inform (and challenge) our understanding of this period in cosmic history. As Dr. Yuan explained, these features are in stark contrast to galaxies as they exist today. But equally interesting is the fact that it also differentiates this spiral galaxy from other galaxies that are similar in age.

“This galaxy is forming stars 20 times faster than galaxies today – as fast as other young galaxies of similar masses in the early Universe,” said Dr. Yuan. “However, unlike other galaxies of the same epoch, A1689B11 has a very cool and thin disc, rotating calmly with surprisingly little turbulence. This type of spiral galaxy has never been seen before at this early epoch of the Universe!”

Illustration of the depth by which Hubble imaged galaxies in prior Deep Field initiatives, in units of the Age of the Universe. Credit: NASA and A. Feild (STScI)

In the future, the team hopes to conduct further studies of this galaxy to further resolve its structure and nature, and to compare it to other spiral galaxies from this epoch. Of particular interest to them is when the onset of spiral arms takes place, which should serve as a sort of boundary marker between ancient elliptical galaxies and modern spiral, lenticular and irregular shapes.

They will continue to rely on the NIFS to conduct these studies, but the team also hopes to rely on data collected by the James Webb Space Telescope (which will be launched in 2019). These and other surveys in the coming years are expected to reveal vital information about the earliest galaxies in the Universe, and reveal further clues as to how it changed over time.

Further Reading: Swinburne, APJ

The SpaceX Booster is Back in Town, Legs Quickly Detached: Photo/Video Gallery

Recovered SpaceX first stage booster from KoreaSat-5A launch is towed into the mouth of Port Canaveral, FL atop OCISLY droneship to flocks of birds and onlookers as Atlantic Ocean waves crash onshore at sunset Nov. 2, 2017. Credit: Ken Kremer/Kenkremer.com
Recovered SpaceX first stage booster from KoreaSat-5A launch is towed into the mouth of Port Canaveral, FL atop OCISLY droneship to flocks of birds and onlookers as Atlantic Ocean waves crash onshore at sunset Nov. 2, 2017. Credit: Ken Kremer/Kenkremer.com

PORT CANAVERAL/KENNEDY SPACE CENTER, FL – ‘The SpaceX boosters back in town! The boosters back in town!’ paraphrasing the popular lyrics of the hit single from Irish hard rock band Thin Lizzy – its what comes to mind with the speedy cadence of ‘launch, land and relaunch’ firmly established by CEO Elon Musk’s hard rocking crew of mostly youthful rocket scientists and engineers.

Barely three days after successfully launching the commercial KoreaSat-5A telecomsat on Monday Oct 30, the SpaceX Falcon 9 first stage booster that did the heavy lifting to orbit generating 1.7 million pounds of liftoff thrust – arrived back in town Thursday, Nov. 2 or more specifically back into Port Canaveral, Florida.

“Guess who’s back in town?” – the song continues – well its the Falcon 9 that reached the edge of space on Halloween Eve while traveling several thousand miles per hour, flipped around like a witches broom and carried out a pinpoint propulsive and upright touchdown of what amounts to a stick on a board in the middle of the Atlantic Ocean. Just amazing!

Floating atop the football field sized platform upon which it soft landed 8.5 minutes after the two stage Falcon 9 lifted off at 3:34 p.m. EDT (1934 GMT) from seaside Launch Complex 39A at NASA’s Kennedy Space Center in Florida. The 16 story tall booster arrived back into the mouth of Port Canaveral late Thursday at sunset – as witnessed up close by myself and several space journalist colleagues.

Check out our expanding photo and video gallery compiled here of the boosters arrival into Port on the OCISLY droneship. The gallery is growing so check back again for more up close looks of the ocean arrival, sailing and docking.

Used SpaceX first stage booster from KoreaSat-5A launch sails into the mouth of Port Canaveral, FL at sunset Nov. 2, 2017. Credit: Julian Leek

Furthermore the four landing legs that made the landing sequence possible – have already been quickly detached by workers this afternoon, as shown here with additional incredible up close imagery.

Up close look as technicians quickly work to detach all 4 landing legs from the recovered SpaceX Falcon 9 Koreasat-5A booster on Nov. 3, 2017 after it sailed into Port Canaveral the day before. Credit: Ken Kremer/Kenkremer.com
Up close look as technicians quickly work to detach all 4 landing legs from the recovered SpaceX Falcon 9 Koreasat-5A booster on Nov. 3, 2017 after it sailed into Port Canaveral the day before. Credit: Ken Kremer/Kenkremer.com

Plus also featured are lots of imagery of the booster sailing through the narrow channel of Port Canaveral – often past seemingly oblivious spectators and pleasure craft who have no idea what they are seeing. As well as imagery of work crews processing the booster for the eventual return back onto base.

Recovered SpaceX first stage booster from KoreaSat-5A launch is towed into the mouth of Port Canaveral, FL atop OCISLY droneship to flocks of birds and onlookers as Atlantic Ocean waves crash onshore at sunset Nov. 2, 2017. Credit: Ken Kremer/Kenkremer.com

The 156 foot-tall first stage atop OCISLY was towed from the Atlantic Ocean landing zone located several hundred miles off shore of the Florida’s East coast back into Port Canaveral by a tugboat named “Hawk.”

The Hawk was accompanied by a small naval flotilla of commercial vessels SpaceX leased for the occasion.

Entering the mouth of Port Canaveral channel at sunset Nov. 2, 2017, a tugboat tows the recovered SpaceX first stage booster from KoreaSat-5A launch atop OCISLY droneship. Credit: Ken Kremer/Kenkremer.com

In fact with each booster return the SpaceX technicians are progressing faster and faster carrying out the booster processing involving safing, cap and line attachment, leg removal, and lowering the booster for horizontal placement on a specially outfitted lengthy multi-wheeled trailer for hauling back to SpaceX hangar facilities on the Kennedy Space Center and Cape Canaveral Air Force Station.

Entering the mouth of Port Canaveral channel at sunset Nov. 2, 2017, a tugboat tows the recovered SpaceX first stage booster from KoreaSat-5A launch atop OCISLY droneship. Credit: Ken Kremer/Kenkremer.com

After arriving in port, and sailing through the channel for about 45 minutes the SpaceX flotilla carefully and methodically edged the droneship closer to shore and docked the vessel last night – and the crews got a well deserved rest as the booster basked in the maritime glow producing beautiful water reflection vistas.

SpaceX Falcon 9 booster from Koreasat-5A launch stands tall and rests at night on droneship after Port Canaveral arrival Nov. 2, 2017. Credit: Ken Kremer/Kenkremer.com

The team wasted no time this morning. At the crack of dawn they began the task of attaching a hoisting cap to the top of the first stage.

Shortly after 9 a.m. EDT they craned the booster off OCISLY and onto a restraining pedestal platform on land.

The techs were working fast and making mincemeat of the booster.

They detached the four insect like legs one after another in an operation that looked a lot like a well thought out dissection.

One at a fime over a period about roughly two hour the workers methodically unbolted and detached the legs in 2 pieces. First they they slung a harness around the upper strut and removed it with a small crane. Then they did the same with the lower foot pad.

Altogether the land leg amputation operation took about 2.5 hours.

The now legless Falcon 9 stands erect. It will soon be lowered and placed horizontally for transport back to the base.

SpaceX Falcon 9 first stage booster is hoisted off OCISLY droneship after being towed through the channel of Port Canaveral, FL on Nov. 2. It successfully launched KoreaSat-5A telecomsat to orbit on Oct. 30, 2017. Credit: Ken Kremer/Kenkremer.com

It has been barely two weeks after the last dogeship landed booster arrived back into port in mid-October for the SES-11 launch on October 11 and sunrise port arrival on October 15.

OCISLY which stands for “Of Course I Still Love You” left Port Canaveral several days ahead of the planned Oct. 30 launch and was prepositioned in the Atlantic Ocean several hundred miles (km) off the US East coast, awaiting the boosters 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.

Watch this video of the SpaceX booster return to Port Canaveral, FL, from the KoreaSat-5 mission:

Video caption: The booster from the KoreaSat-5 mission returns to Port Canaveral, FL, on the SpaceX drone ship ‘Of Course I Still Love You” on Nov. 2, 2017 after a successful landing at sea. Credit: Jeff Seibert

Video caption: After launching from the Kennedy Space LC-39A the SpaceX Falcon 9 first stage landed on the OCISLY droneship offshore. It was towed back to Port Canaveral to be refurbished and used again in a later launch. Credit: Julian Leek

To date SpaceX has accomplished 19 successful landings of a recovered Falcon 9 first stage booster by land and by sea.

SpaceX Falcon 9 blasts off with KoreaSat-5A commercial telecomsat atop Launch Complex 39A at the Kennedy Space Center, FL, on Halloween eve 30 Oct 2017. As seen from inside the pad perimeter. Credit: Ken Kremer/Kenkremer.com

Watch for Ken’s continuing onsite coverage of SpaceX KoreaSat-5A & 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

Flight proven SpaceX first stage booster from KoreaSat-5A launch is towed into the mouth of Port Canaveral, FL amidst a flock of birds encircling OCISLY droneship at sunset Nov. 2, 2017. Credit: Ken Kremer/Kenkremer.com
Entering the mouth of Port Canaveral channel at sunset Nov. 2, 2017, a tugboat tows the recovered SpaceX first stage booster from KoreaSat-5A launch atop OCISLY droneship. Credit: Ken Kremer/Kenkremer.com
SpaceX used booster from Koreasat-5A launch sails through Port Canaveral atop OCISLY droneship at sunset Nov. 2, 2017. Credit: Ken Kremer/Kenkremer.com
Fisherman enjoys serene sunset as SpaceX used booster from Koreasat-5A launch sails through Port Canaveral atop OCISLY droneship on Nov. 2, 2017. Credit: Ken Kremer/Kenkremer.com
Flight proven SpaceX first stage booster from KoreaSat-5A launch sails into the mouth of Port Canaveral, FL at sunset Nov. 2, 2017. Credit: Dawn Leek Taylor
Used SpaceX first stage booster from KoreaSat-5A launch sails into the mouth of Port Canaveral, FL at sunset Nov. 2, 2017. Credit: Julian Leek
Flight proven SpaceX first stage booster from KoreaSat-5A launch sails into the mouth of Port Canaveral, FL at sunset Nov. 2, 2017. Credit: Julia Bergeron