Adieu Titan: So Long & Thanks For All The Hydrocarbons

Artist's conception of Cassini winging by Saturn's moon Titan (right) with the planet in the background. Credit: NASA/JPL-Caltech

The Cassini spacecraft has done some amazing things since it arrived in the Saturn system in 2004. In addition to providing valuable information on the gas giant and its system of rings, it has also provided us with extensive data and photographs of Saturn’s many moons. Nowhere has this been more apparent than with Saturn’s largest moon, the hydrocarbon-rich satellite known as Titan.

And with just a few hours left before Cassini makes its final plunge between Saturn and its innermost ring (something that no other spacecraft has ever done), we should all take this opportunity to say goodbye to Titan. In the past few years, it has dazzled us with its methane lakes, dense atmosphere, and potential for hosting life. And it shall be sorely missed!

Cassini’s last encounter with Titan – where it passed within 979 km (608 mi) of the moon’s surface – took place on April 21st, at 11:08 p.m. PDT (April 22nd, 2:08 a.m. EDT). The probe also used this opportunity to take some radar images of the moon’s northern polar region. While this area has been photographed before, this was the first time that radar images were acquired.

*Unprocessed image of Saturn’s moon Titan, captured by NASA’s Cassini spacecraft during its final close flyby on April 21st, 2017. Credit: NASA/JPL-Caltech/Space Science Institute*

Over the course of the next week, Cassini’s radar team hopes to pour over theses images, which provide a detailed look at the methane seas and lakes in the northern polar region. It is hoped that this data will allow scientists to shed more light on the depths and compositions of some of the small lakes in the area, as well as provide more information on the evolving surface feature known as “magic island“.

With this last pass complete (its 127th in total), Cassini is now beginning the final phase of its mission – known as the Grand Finale. This will consist of the spacecraft making a final set of 22 orbits around the ringed planet between April 26th and September 15th. The maneuver will allow Cassini to go where no other probe has gone before and get the closest look ever at Saturn’s outer rings.

The final pass over Titan was part of this maneuver, using the moon’s gravity to bend and reshape the probe’s orbit so that it would be able to pass through Saturn’s ring system – instead of passing just beyond the main rings. As Earl Maize, Cassini project manager at JPL, said in a NASA press release:

“With this flyby we’re committed to the Grand Finale. The spacecraft is now on a ballistic path, so that even if we were to forgo future small course adjustments using thrusters, we would still enter Saturn’s atmosphere on Sept. 15 no matter what.”

*Some key numbers for Cassini’s Grand Finale and final plunge into Saturn. Credit: NASA/JPL-Caltech*

Cassini’s final pass with Titan allowed it to acquire a boost in velocity, increasing its speed by 860.5 meters per second (3098 km/h; 1,925 mph). It then reached its farthest point in its orbit around Saturn (apoapse) on April 22nd, :46 p.m. PDT (11:46 p.m. EDT). This effectively began the Grand Finale orbits, with the first dive coming on April 26th, at 02:00 a.m. PDT (05:00 a.m. EDT).

This orbit will provide Cassini with its best look to date at Saturn’s north pole, which it will be studying with both its Visible and Infrared Mapping Spectrometer (VIMS) and Composite Infrared Spectrometer (CIRS). These studies will lead to the creation of the sharpest movies to date in the near-infrared band, which will also allow the science team to study the motions of the hexagon pattern around Saturn’s north pole in more detail.

Between now and September, when the mission will end, the probe will provide information that is expected to improve our understanding of how giant planets form and evolve. Things will finally wrap on September 15th, 2017, when the probe will plunge into Saturn’s atmosphere. But even then, the probe will be sending back information until its very last seconds of operation.

Safe journeys Cassini! And so long Titan! We hope to be exploring you again someday soon, preferably with something that can float or fly around inside your dense atmosphere, or perhaps investigate your methane seas in serious depth!

In the meantime, be sure to check out this narrated, 360-degree animated video from NASA. As you can see, it simulates what a ride on the Cassini spacecraft might look like as it makes its Grand Finale:

Further Reading: NASA, Cassini – The Grand Finale

April 25, 2017April 28, 2017 by Evan Gough

Another Strange Discovery From LHC That Nobody Understands

New results from ALICE at the Large Hadron Collider show so-called strange hadrons being created where none were expected. As the number of proton-proton collisions (the blue lines) increase, the more of these strange hadrons are seen (as shown by the red squares in the graph). (Image: CERN)

There are some strange results being announced in the physics world lately. A fluid with a negative effective mass, and the discovery of five new particles, are all challenging our understanding of the universe.

New results from ALICE (A Large Ion Collider Experiment) are adding to the strangeness.

ALICE is a detector on the Large Hadron Collider (LHC). It’s one of seven detectors, and ALICE’s role is to “study the physics of strongly interacting matter at extreme energy densities, where a phase of matter called quark-gluon plasma forms,” according to the CERN website. Quark-gluon plasma is a state of matter that existed only a few millionths of a second after the Big Bang.

In what we might call normal matter—that is the familiar atoms that we all learn about in high school—protons and neutrons are made up of quarks. Those quarks are held together by other particles called gluons. (“Glue-ons,” get it?) In a state known as confinement, these quarks and gluons are permanently bound together. In fact, quarks have never been observed in isolation.

A cut-away view of the ALICE detector at CERN’s LHC. Image: By Pcharito – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=31365856

The LHC is used to collide particles together at extremely high speeds, creating temperatures that can be 100,000 times hotter than the center of our Sun. In new results just released from CERN, lead ions were collided, and the resulting extreme conditions come close to replicating the state of the Universe those few millionths of a second after the Big Bang.

In those extreme temperatures, the state of confinement was broken, and the quarks and gluons were released, and formed quark-gluon plasma.

So far, this is pretty well understood. But in these new results, something additional happened. There was increased production of what are called “strange hadrons.” Strange hadrons themselves are well-known particles. They have names like Kaon, Lambda, Xi and Omega. They’re called strange hadrons because they each have one “strange quark.”

If all of this seems a little murky, here’s the dinger: Strange hadrons may be well-known particles, because they’ve been observed in collisions between heavy nuclei. But they haven’t been observed in collisions between protons.

“Being able to isolate the quark-gluon-plasma-like phenomena in a smaller and simpler system…opens up an entirely new dimension for the study of the properties of the fundamental state that our universe emerged from.” – Federico Antinori, Spokesperson of the ALICE collaboration.

“We are very excited about this discovery,” said Federico Antinori, Spokesperson of the ALICE collaboration. “We are again learning a lot about this primordial state of matter. Being able to isolate the quark-gluon-plasma-like phenomena in a smaller and simpler system, such as the collision between two protons, opens up an entirely new dimension for the study of the properties of the fundamental state that our universe emerged from.”

Enhanced Strangeness?

The creation of quark-gluon plasma at CERN provides physicists an opportunity to study the strong interaction. The strong interaction is also known as the strong force, one of the four fundamental forces in the Universe, and the one that binds quarks into protons and neutrons. It’s also an opportunity to study something else: the increased production of strange hadrons.

In a delicious turn of phrase, CERN calls this phenomenon “enhanced strangeness production.” (Somebody at CERN has a flair for language.)

Enhanced strangeness production from quark-gluon plasma was predicted in the 1980s, and was observed in the 1990s at CERN’s Super Proton Synchrotron. The ALICE experiment at the LHC is giving physicists their best opportunity yet to study how proton-proton collisions can have enhanced strangeness production in the same way that heavy ion collisions can.

According to the press release announcing these results, “Studying these processes more precisely will be key to better understand the microscopic mechanisms of the quark-gluon plasma and the collective behaviour of particles in small systems.”

I couldn’t have said it better myself.

April 25, 2017 by Susie Murph

Carnival of Space #506

Carnival of Space. Image by Jason Major.

This week’s Carnival of Space is hosted by Allen Versfeld at his Urban Astronomer blog.

Click here to read Carnival of Space #506.
Continue reading “Carnival of Space #506”

April 24, 2017April 26, 2017 by Ken Kremer

NASA Astronaut Peggy Whitson Sets US Space Endurance Record, Speaks to President Trump

NASA astronaut Peggy Whitson, currently living and working aboard the International Space Station, broke the record Monday for cumulative time spent in space by a U.S. astronaut – an occasion that was celebrated with a phone call from President Donald Trump, First Daughter Ivanka Trump, and fellow astronaut Kate Rubins. Credits: NASA TV

NASA Astronaut Peggy Whitson set the endurance record for time in space by a U.S, astronaut today, Monday, April 24, during her current stint of living and working aboard the International Space Station (ISS) along with her multinational crew of five astronauts and cosmonauts.

Furthermore Whitson received a long distance phone call of exuberant congratulations from President Donald Trump, First Daughter Ivanka Trump, and fellow astronaut Kate Rubins direct from the Oval Office in the White House to celebrate the momentous occasion.

“This is a very special day in the glorious history of American spaceflight!” said President Trump during the live phone call to the ISS broadcast on NASA TV.

As of today, Whitson exceeded 534 cumulative days in space by an American astronaut, breaking the record held by NASA astronaut Jeff Williams.

“Today Commander Whitson you have broken the record for the most total time spent in space by an American astronaut. 534 days and counting,” elaborated President Trump.

“That’s an incredible record to break. And on behalf of the nation and frankly the world I would like to congratulate you. That is really something!”

“You’re an incredible inspiration to us all.”

Trump noted that thousands of school students were listening in to the live broadcast which also served to promote students to study STEM subjects.

“Peggy is a phenomenal role model for young women, and all Americans, who are exploring or participating in STEM education programs and careers,” said President Trump.

“As I have said many times before, only by enlisting the full potential of women in our society will we be truly able to make America great again. When I signed the INSPIRE Women Act in February, I did so to ensure more women have access to STEM education and careers, and to ensure America continues to benefit from the contributions of trailblazers like Peggy.”

How does it feel to break the endurance record? Trump asked Whitson.

“It’s actually a huge honor to break a record like this, but it’s an honor for me basically to be representing all the folks at NASA who make this spaceflight possible and who make me setting this record feasible,” Whitson replied from orbit to Trump.

“And so it’s a very exciting time to be at NASA. We are all very much looking forward, as directed by your new NASA bill — we’re excited about the missions to Mars in the 2030s. And so we actually, physically, have hardware on the ground that’s being built for the SLS rocket that’s going to take us there.”

“It’s a very exciting time, and I’m so proud of the team.”

“We have over 200 investigations ongoing onboard the space station, and I just think that’s a phenomenal part of the day.”

NASA astronaut Jack Fischer is also serving aboard the station on his rookie flight and also took part in the phone call with President Trump.

Whitson is currently serving as Space Station Commander of Expedition 51. She most recently launched to the ISS on Nov 17, 2016 aboard a Russian Soyuz capsule from the Baikonur Cosmodrome in Kazakhstan, as part of a three person crew.

At the time of her Soyuz launch she had accumulated 377 total days in space.

She holds several other prestigious records as well. Whitson is the first woman to serve twice as space station commander.

Indeed in 2008 Whitson became the first woman ever to command the space station during her prior stay on Expedition 16 a decade ago. Her second stint as station commander began earlier this month on April 9.

Whitson also holds the record for most spacewalks by a female astronaut. Altogether she has accumulated 53 hours and 23 minutes of EVA time over eight spacewalks.

Overall, Expedition 51 involved her third long duration stay aboard the massive orbiting laboratory complex.

Seen here on a spacewalk in March 2017, NASA astronaut Peggy Whitson holds the record for most spacewalks conducted by a female astronaut. Credits: NASA

“This is an inspirational record Peggy is setting today, and she would be the first to tell you this is a record that’s absolutely made to be broken as we advance our knowledge and existence as both Americans and humans,” said NASA acting Administrator Robert Lightfoot, in a statement.

“The cutting-edge research and technology demonstrations on the International Space Station will help us go farther into our solar system and stay there longer, as we explore the mysteries of deep space first-hand. Congratulation to Peggy, and thank you for inspiring not only women, but all Americans to pursue STEM careers and become leaders.”

When she returns to Earth in September she will have accumulated some 666 days in space.

On her 2007 mission aboard the International Space Station, NASA astronaut Peggy Whitson, Expedition 16 commander, worked on the Capillary Flow Experiment (CFE), which observes the flow of fluid, in particular capillary phenomena, in microgravity. Credits: NASA

Trump made note of the science and commercial industrial work being carried out aboard the station.

“Many American entrepreneurs are racing into space. I have many friends that are so excited about space. They want to get involved in space from the standpoint of entrepreneurship and business,” said President Trump.

“And I’m sure that every student watching wants to know, what is next for Americans in space.”

Indeed the private SS John Glenn Cygnus cargo freighter just arrived at the ISS on Saturday, April 22, carrying nearly 4 tons or science experiments, hardware, parts and provisions.

Whitson was one of two ISS astronauts involved in capturing Cygnus with the Canadian built robotic arm for attachment to the stations Unity node.

Trump also mentioned his strong support for sending humans on a mission to Mars in the 2030s and for NASA’s development of the SLS heavy lift rocket and Orion deep space capsule.

“I’m very proud that I just signed a bill committing NASA to the aim of sending America astronauts to Mars. So we’ll do that. I think we’ll do it a lot sooner than we’re even thinking.”

“Well, we want to try and do it during my first term or, at worst, during my second term. So we’ll have to speed that up a little bit, okay?”

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

Ken Kremer

April 24, 2017May 8, 2017 by Tammy Plotner

Messier 40 – the Winnecke 4 Double Star

The double star Messier 40 (Winnecke 4), along with PGC 39934, NGC 4290 and NGC 4284. Credit: Wikisky

Welcome back to Messier Monday! In our ongoing tribute to the great Tammy Plotner, we take a look at the double star known as Messier 40. Enjoy!

During the 18th century, famed French astronomer Charles Messier noted the presence of several “nebulous objects” in the night sky. Having originally mistaken them for comets, he began compiling a list of them so that others would not make the same mistake he did. In time, this list (known as the Messier Catalog) would come to include 100 of the most fabulous objects in the night sky.

One of these objects is Messier 40, this double star is now known to be an optical double star (i.e. two independent stars at different distances that appear aligned based on our perspective). It is also included in the Winnecke Catalogue of Double Stars as number 4, and is located in the constellation of Ursa Major (aka. the Big Dipper).

Description:

At roughly 500 light years away from us, no one is quite sure if this pair of stars is truly a binary system or an optical double star. According to Richard Nugent’s 2002 data, “The observed relative proper motion, as measured in separation and position angle, is consistent with a straight, independent motion of the two stars, one crossing between us and the other.”

The two stars are nearly the same brightness as each other, with the primary star being magnitude 9 and the secondary being magnitude 9.3 and they are separated by about 49 arc seconds – a wide gap. At one time, the angular separation of the pair was measured at 49.2″, but has gradually changed to about 52.8″ in more recent years.

History of Observation:

Messier 40 was discovered by Charles Messier in 1764 while he was searching for a nebula that had been reported in the area by Johann Hevelius. As he wrote at the time:

“The same night on October 24-25, [1764], I searched for the nebula above the tail of the Great Bear [Ursa Major], which is indicated in the book Figure of the Stars, second edition: it should have, in 1660, the right ascension 183d 32′ 41″, and the northern declination 60d 20′ 33″. I have found, by means of this position, two stars very near to each other and of equal brightness, about the 9th magnitude, placed at the beginning of the tail of Ursa Major: one has difficulty to distinguish them with an ordinary refractor of 6 feet. Here are their position: right ascension, 182 deg 45′ 30″, and 59 deg 23′ 50″ northern declination. There is reason to presume that Hevelius mistook these two stars for a nebula.”

History often credits Messier for being a little bit crazy for cataloging a double star, but upon having read Messier’s report, I feel like he was an astronomer doing his job. If Hevelius reported a nebula here – then he was bound to look and write down what he saw. He didn’t just stumble on a double star and catalog it for no reason!

*Close-up of the double star Messier 40. Credit: Wikisky*

Later astronomers would also search for M40 and report a double star, and it was cataloged by such as by Friedrich August Theodor Winnecke at Pulkovo Observatory in 1863 as WNC 4. However, to give the good Hevelius credit, John Mallas reports, “the Hevelius object is the 5th-magnitude star 74 Ursae Majoris, more than one degree away, as reference to his star catalogue will show.”

In 1991, the separation between the stars was measured at 52.8 arcseconds, which represented an increase since 1966, when it was measured at 51.7. In 2001 and 2002, studies conducted by Brian Skiff and Richard L. Nugent suggested that the stars comprising the double star (HD 238107 and HD 238108) were in fact an optical double star, rather than a double star system.

In 2016, by using parallax measurements from the Gaia satellite, this theory was proven for the first time. Distance estimates were also produced, indicating that the two components are 350±30 and 140±5 parsecs (~1141±98 and 456±16 light years).

Locating Messier 40:

Finding Messier 40 isn’t very difficult for fairly large binoculars and small telescopes – but you need to remember that it’s a double star. First locate the easily recognized constellation of Ursa Major and focus on the ‘Big Dipper’ and look for the two stars that form the edge that connect to the handle – Gamma and Delta.

*The location of Messier 40 in Ursa Major, above and to the left of MegrezCredit: IAU and Sky & Telescope magazine (Roger Sinnott & Rick Fienberg)*

Aim your telescope’s finderscope at Delta – the point where the ‘handle’ would connect. In the finder, you will see a fainter star to the northeast. Hop there. Now, using a low power eyepiece, scan slightly further northeast and you will locate M40. Once located, you may go to higher magnification to more closely examine this Messier catalog curiosity.

While this pair of stars will show easily in binoculars, you must remember that binoculars give such a wide field that it will be difficult to distinguish them from surrounding stars. However, this is a great object for light-polluted skies and moonlit nights!

Enjoy the controversy… and this pair! And here are the quick facts on M40 to help you get started:

Object Name: Messier 40
Alternative Designations: M40, WNC 4
Object Type: Double Star
Constellation: Ursa Major
Right Ascension: 12 : 22.4 (h:m)
Declination: +58 : 05 (deg:m)
Distance: 0.51 (kly)
Visual Brightness: 8.4 (mag)
Apparent Dimension: 0.8 (arc min)

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

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

Sources:

April 24, 2017April 8, 2018 by Matt Williams

What is the Average Surface Temperature of Mercury?

MESSENGER image of Mercury from its third flyby (NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington)

Of all the planets in the Solar System, Mercury is the closest to our Sun. As such, you would think it is the hottest of all the Solar planets. But strangely enough, it is not. That honor goes to Venus, which experiences an average surface temperature of 750 K (477 °C; 890 °F). Not only that, but Mercury is also cold enough in some regions to maintain water in ice form.

Overall, Mercury experiences considerable variations in temperatures, ranging from the extremely hot to the extremely cold. All of this arises from the fact that Mercury has an extremely thin atmosphere, as well as the nature of its orbit. Whereas the side facing the Sun experiences temperatures hot enough to melt lead, the darkened areas are cold enough to freeze water.

Orbital Characteristics:

Mercury has the most eccentric orbit of any planet in the Solar System (0.205). Because of this, its distance from the Sun varies between 46 million km (29 million mi) at its closest (perihelion) to 70 million km (43 million mi) at its farthest (aphelion). And with an average orbital velocity of 47.362 km/s (29.429 mi/s), it takes Mercury a total 87.969 Earth days to complete a single orbit around the Sun.

With an average rotational speed of 10.892 km/h (6.768 mph), Mercury also takes 58.646 days to complete a single rotation. This means that Mercury has a spin-orbit resonance of 3:2, which means that it completes three rotations on its axis for every two orbits around the Sun. This does not, however, mean that three days last the same as two years on Mercury.

In fact, its high eccentricity and slow rotation mean that it takes 176 Earth days for the Sun to return to the same place in the sky (aka. a solar day), which means that one day is twice as long as a single year on Mercury. The planet also has the lowest axial tilt of any planet in the Solar System – approximately 0.027° compared to Jupiter’s 3.1°, (the second smallest). This means that there is virtually no seasonal variation in surface temperature.

Exosphere:

Another factor that affects Mercury’s surface temperatures is its extremely thin atmosphere. Mercury is essentially too hot and too small to retain anything more than a variable “exosphere”, one which is made up of hydrogen, helium, oxygen, sodium, calcium, potassium and water vapor.

The Fast Imaging Plasma Spectrometer on board MESSENGER has found that the solar wind is able to bear down on Mercury enough to blast particles from its surface into its wispy atmosphere. Credit: Carolyn Nowak/Media Academica, LLC

These trace gases have a combined atmospheric pressure of about 10^-14 bar (one-quadrillionth of Earth’s atmospheric pressure). It is believed this exosphere was formed from particles captured from the Sun, volcanic outgassing and debris kicked into orbit by micrometeorite impacts.

Surface Temperatures:

Because it lacks a viable atmosphere, Mercury has no way to retain the heat from the Sun. As a result of this and its high eccentricity, the planet experiences considerable variations in temperature between its light side and dark side. Whereas the side that faces the Sun can reach temperatures of up to 700 K (427° C; 800 °F), the side in shadow dips down to 100 K (-173° C: -279 °F).

Despite its extreme highs in temperature, the existence of water ice and even organic molecules has been confirmed on Mercury’s surface, specifically in the cratered northern polar region. Since the floors of these deep craters are never exposed to direct sunlight, temperatures there remain below the planetary average.

*View of Mercury’s north pole. based on MESSENGER probe data, showing polar deposits of water ice. Credit: NASA/JHUAPL/Carnegie/National Astronomy and Ionosphere Center, Arecibo Observatory.*

These icy regions are believed to contain about 10¹⁴–10¹⁵ kg of frozen water, and may be covered by a layer of regolith that inhibits sublimation. The origin of the ice on Mercury is not yet known, but the two most likely sources are from outgassing of water from the planet’s interior or deposition by the impacts of comets. There are thought to be craters at the south pole as well, where temperatures are similarly cold enough to sustain water in ice form.

Mercury is a planet of extremes. It has an extremely eccentric orbit, an extremely thin-atmosphere, and experiences extremely hot and cold surface temperatures. Little wonder then why there is no life on the planet (at least, that we know about!) But perhaps someday, human beings may live there, sheltered in the cratered regions and using the water ice to create a habitat.

If you’d like more information on Mercury, check out NASA’s Solar System Exploration Guide, and here’s a link to NASA’s MESSENGER Misson Page.

We have also recorded a whole episode of Astronomy Cast that’s just about planet Mercury. Listen to it here, Episode 49: Mercury.

Sources:

April 24, 2017April 28, 2017 by Evan Gough

Into The Submillimeter: The Early Universe’s Formation

A new study looked at 52 submillimeter galaxies to help us understand the early ages of our Universe. Image: University of Nottingham/Omar Almaini

In order to make sense of our Universe, astronomers have to work hard, and they have to push observing technology to the limit. Some of that hard work revolves around what are called sub-millimeter galaxies (SMGs.) SMGs are galaxies that can only be observed in the submillimeter range of the electromagnetic spectrum.

The sub-millimeter range is the waveband between the far-infrared and microwave wavebands. (It’s also called Terahertz radiation.) We’ve only had the capability to observe in the sub-millimeter range for a couple decades. We’ve also increased the angular resolution of telescopes, which helps us discern separate objects.

The submillimter wavelength is also called Terahertz Radiation, and is between Infrared and Microwave Radiation on the spectrum. Image: By Tatoute, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=6884073

SMGs themselves are dim in other wavelengths, because they’re obscured by dust. The optical light is blocked by the dust, and absorbed and re-emitted in the sub-millimeter range. In the sub-millimeter, SMGs are highly luminous; trillions of times more luminous than the Sun, in fact.

This is because they are extremely active star-forming regions. SMGs are forming stars at a rate hundreds of times greater than the Milky Way. They are also generally older, more distant galaxies, so they’re red-shifted. Studying them helps us understand galaxy and star formation in the early universe.

ALMA is an array of dishes located at the Atacama Desert in Chile. Image: ALMA (ESO/NAOJ/NRAO), O. Dessibourg

A new study, led by James Simpson of the University of Edinburgh and Durham University, has examined 52 of these galaxies. In the past, it was difficult to know the exact location of SMGs. In this study, the team relied on the power of the Atacama Large Millimeter/submillimeter array (ALMA) to get a much more precise measurement of their location. These 52 galaxies were first identified by the Submillimeter Common-User Bolometer Array (SCUBA-2) in the UKIDSS Ultra Deep Survey.

There are four major results of the study:

48 of the SMGs are non-lensed, meaning that there is no object of sufficient mass between us and them to distort their light. Of these, the team was able to constrain the red-shift (z) for 35 of them to a median range of z-2.65. When it comes to extra-galactic observations like this, the higher the red-shift, the further away the object is. (For comparison, the highest red-shift object we know of is a galaxy called GN-z11, at z=11.1, which corresponds to about 400 million years after the Big Bang.
Another type of galaxy, the Ultra-Luminous Infrared Galaxy (ULIRG) were thought to be evolved versions of SMGs. But this study showed that SMGs are larger and cooler than ULIRGs, which means that any evolutionary link between the two is unlikely.
The team calculated estimates of dust mass in these galaxies. Their estimates suggest that effectively all of the optical-to-near-infrared light from co-located stars is obscured by dust. They conclude that a common method in astronomy used to characterize astronomical light sources, called Spectral Energy Distribution (SED), may not be reliable when it comes to SMGs.
The fourth result is related to the evolution of galaxies. According to their analysis, it seems unlikely that SMGs can evolve into spiral or lenticular galaxies (a lenticular galaxy is midway between a spiral and an elliptical galaxy.) Rather, it appears that SMGs are the progenitors of elliptical galaxies.

The Pinwheel Galaxy (M101, NGC 5457) is a stunning example of a spiral galaxy. This study determines that there likely is no evolutionary link between sub-millimeter galaxies and spiral galaxies. Image: European Space Agency & NASA. CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=36216331

This study was a pilot study that the team hopes to extend to many other SMGs in the future.

April 23, 2017April 23, 2017 by Fraser Cain

Join Fraser and Friends for a COSMOS Marathon on Monday

Viking Lander — In 1976, two Viking spacecraft landed on Mars. The image is of a model of the Viking lander, along with astronomer and pioneering astrobiologist Carl Sagan. Each lander was equipped with life detection experiments designed to detect life based on its metabolic activities. Credits: NASA/Jet Propulsion Laboratory, Caltech

Click here on Monday, April 24th at 12:00 pm PST to join the livestream.

Remember COSMOS, with Carl Sagan? Of course you do. If you’re fascinated with space and astronomy like me, then the original COSMOS must have had a pivotal impact on your enthusiasm for all things space. And not just space, but all things science. I don’t think it’s an understatement to say that Carl Sagan completely changed the paradigm for what it means to be a science communicator. He revealed the discoveries made by astronomers, and made them accessible to a general audience – and he took a lot of heat for it.

Unfortunately, Carl Sagan died of cancer in 1996, years too early. He changed the world, but he never got to stick around and see his impact echoing through the Internet as it has today. When I started Universe Today in 1999, it was because the ideas in Pale Blue Dot resonated so deeply with me. I wanted to dedicate my life to understanding and teaching the world about space. And I’m always sad that I never got a chance to meet with him, and tell him how much of an influence he had on my career. Demon Haunted World taught me to be a skeptic.

I’ve had an idea kicking around for years now. I’ve always wanted to watch the entire COSMOS series with a bunch of my space friends, and do a live commentary. Partly to update the science, partly to reflect on Sagan’s influence, and partly to just hang out with a bunch of friends and be silly. But I could never figure out how I could navigate the copyright issues to be able to broadcast something based on COSMOS. And Ann Druyan would kill me.

Well, my friends at Twitch.tv have decided to grant my wish, and they’re going to be running a COSMOS marathon on Monday, April 24, 2017 at 12:00 pm PST. Not only that, but they’re encouraging other livestreamers to co-stream the show, and do exactly what I’ve always wanted to do – provide a commentary.

The challenge is that it’s a marathon, which means they’re going to run all 13 episodes back to back. 13 hours of watching COSMOS with my friends, chatting about the show, answering questions, and having fun. I’m up for it. But then, I’m a glutton for punishment.

So, if you’re interested in the raw Twitch stream and all the other cool events that Twitch has planned over the next week, check out their announcement.

And if you want to join me for some or all of the COSMOS marathon, follow fcain on Twitch. I’ll be starting up my livestream when the main feed goes live. And in theory, I’ll be sticking around until the whole thing ends 13 hours later.

Over the course of the livestream, I’ll be joined by many of my space and astronomy journalist friends. Like Dr. Ian O’Neill, Morgan Rehnberg, Nancy Atkinson, Dr. Brian Koberlein, and Dr. Paul Matt Sutter.

Hang out with us, ask questions, chat about your memories and experiences with Carl Sagan’s COSMOS.

I’ll see you on Monday!

April 23, 2017April 24, 2017 by Matt Williams

Team Creates Negative Effective Mass In The Lab

Credit: ESA/Hubble, ESO, M. Kornmesser — Researchers at WSU have created a fluid with a negative effective mass for the first time, which could open the door to studying the deeper mysteries of the Universe. Credit: ESA/Hubble, ESO, M. Kornmesse

When it comes to objects and force, Isaac Newton’s Three Laws of Motion are pretty straightforward. Apply force to an object in a specific direction, and the object will move in that direction. And unless there’s something acting against it (like gravity or air pressure) it will keep moving in that direction until something stops it. But when it comes to “negative mass”, the exact opposite is true.

As the name would suggest, the term refers to matter whose mass is opposite that of normal matter. Until a few years ago, negative mass was predominantly a theoretical concept and had only been observed in very specific settings. But according to a recent study by an international team of researchers, they managed to create a fluid with a “negative effective mass” under laboratory conditions for the first time .

To put it in the simplest terms, matter can have a negative mass in the same way that a particle can have a negative charge. When it comes to the Universe that we know and study on a regular basis, one could say that we have encountered only the positive form of mass. In fact, one could say that it is the same situation with matter and antimatter. Theoretical physics tells us both exist, but we only see the one on a regular basis.

As Dr. Michael McNeil Forbes – a Professor at Washington State University, a Fellow at the Institute for Nuclear Theory, and a co-author on the study – explained in a WSU press release:

“That’s what most things that we’re used to do. With negative mass, if you push something, it accelerates toward you. Once you push, it accelerates backwards. It looks like the rubidium hits an invisible wall.”

According to the team’s study, which was recently published in the Physical Review Letters (under the title “Negative-Mass Hydrodynamics in a Spin-Orbit–Coupled Bose-Einstein Condensate“), a negative effective mass can be created by altering the spin-orbit coupling of atoms. Led by Peter Engels – a professor of physics and astronomy at Washington State University – this consisted of using lasers to control the behavior of rubidium atoms.

They began by using a single laser to keep rubidium atoms in a bowl measuring less than 100 microns across. This had the effect of slowing the atoms down and cooling them to just a few degrees above absolute zero, which resulted in the rubidium becoming a Bose-Einstein condensate. Named after Satyendra Nath Bose and Albert Einstein (who predicted how their atoms would behave) these types of condensates behaves like a superfluid.

*Velocity-distribution data (3 views) for a gas of rubidium atoms, confirming the discovery of a new phase of matter, the Bose–Einstein condensate. Credit: NIST/JILA/CU-Boulder*

Basically, this means that their particles move very slowly and behave like waves, but without losing any energy. A second set of lasers was then applied to move the atoms back and forth, effectively changing the way they spin. Prior to the change in their spins, the superfluid had regular mass and breaking the bowl would result in them pushing out and expanding away from their center of mass.

But after the application of the second laser, the rubidium rushed out and accelerated in the opposite direction – consistent with how a negative mass would. This represented a break with previous laboratory experiments, where researchers were unable to get atoms to behave in a way that was consistent with negative mass. But as Forbes explained, the WSU experiment avoided some of the underlying defects encountered by these experiments:

“What’s a first here is the exquisite control we have over the nature of this negative mass, without any other complications. It provides another environment to study a fundamental phenomenon that is very peculiar.”

And while news of this experiment has been met with fanfare and claims to the effect that the researchers had “rewritten the laws of physics”, it is important to emphasize that this research has created a “negative effective mass” – which is fundamentally different from a negative mass.

*Artist’s rendering of an outburst on an ultra-magnetic neutron star, also called a magnetar.*
*Credit: NASA/Goddard Space Flight Center*

As Sabine Hossenfelder, a Research Fellow at the Frankfurt Institute for Advanced Studies, wrote on her website Backreaction in response to the news:

“Physicists use the preamble ‘effective’ to indicate something that is not fundamental but emergent, and the exact definition of such a term is often a matter of convention. The ‘effective radius’ of a galaxy, for example, is not its radius. The ‘effective nuclear charge’ is not the charge of the nucleus. And the ‘effective negative mass’ – you guessed it – is not a negative mass. The effective mass is merely a handy mathematical quantity to describe the condensate’s behavior.”

In other words, the researchers were able to get atoms to behave as a negative mass, rather than creating one. Nevertheless, their experiment demonstrates the level of control researchers now have when conducting quantum experiments, and also serves to clarify how negative mass behaves in other systems. Basically, physicists can use the results of these kinds of experiments to probe the mysteries of the Universe where experimentation is impossible.

These include what goes on inside neutron stars or what transpires beneath the veil of a event horizon. Perhaps they could even shed some light on questions relating to dark energy.

Further Reading: Physical Review Letters, WSU

April 23, 2017April 24, 2017 by Ken Kremer

SS John Glenn Stellar Space Station Launch – Photo/Video Gallery

Orbital ATK’s seventh cargo delivery flight to the International Space Station -in tribute to John Glenn- launched at 11:11 a.m. EDT April 18, 2017, on a United Launch Alliance Atlas V rocket from Space Launch Complex 41 on Cape Canaveral Air Force Station in Florida. Credit: Ken Kremer/kenkremer.com

KENNEDY SPACE CENTER, FL – This week’s blastoff of the ‘SS John Glenn’ Cygnus cargo freighter atop an Atlas V rocket on a critical mission delivering over 7000 pounds of science and gear to the International Space Station (ISS) yielded stellar imagery from all around the Florida Space Coast.

On the occasion of what amounts to a sentimental third journey to space for NASA astronaut John Glenn – the first American to orbit Earth – near perfect weather conditions enabled spectacular views of the lunchtime liftoff of the United Launch Alliance Atlas V carrying Orbital ATK’s commercial Cygnus supply ship named in honor of a true American hero.

The SS John Glenn blasted to orbit on time at 11:11 a.m. EDT Tuesday, April 18 atop a United Launch Alliance Atlas V rocket from Space Launch Complex 41 on Cape Canaveral Air Force Station in Florida.

The cargo ship safely reached the station early Saturday morning.

The stunning launch events were captured by journalists and tourists gathered from across the globe.

Liftoff of Orbital ATK SS John Glenn OA-7 mission atop ULA Atlas V rocket from Space Launch Complex 41 at Cape Canaveral Air Force Station, FL on April 18, 2017. Credit: Julian Leek

Check out this expanding gallery of eyepopping photos and videos from several space journalist colleagues and friends and myself – for views you won’t see elsewhere.

Click back as the gallery grows !

Watch this truly magnificent and unique video from space journalist Jeff Seibert positioned at a Playalinda Beach on the Atlantic Ocean – as excited vacationers and space enthusiasts frolic together in the waves and sands of this public beach.

Video Caption: Launch of Orbital ATK OA-7 Cygnus cargo vessel viewed from Playalinda Beach, FL on April 18, 2017. An Atlas 5 rocket launching a Cygnus cargo vessel, the “S.S. John Glenn” to the ISS loaded with 7452 pounds of science equipment, experiments, consumables and spare parts. Credit: Jeff Seibert

Playalinda is located just north of NASA’s Launch Complex 39A and offers the closest and clearest possible views of Atlas rocket launches from only about 5 miles away.

Four days after liftoff the SS John Glenn finally arrived at the station as planned Saturday morning April 22 following a carefully choreographed series of thruster maneuvers this past week.

The private Cygnus resupply vessel is carrying nearly four tons of science and supplies crammed inside for the five person multinational Expedition 51 crew.

After reaching the vicinity of the space station overnight Saturday, Cygnus was successfully captured by astronaut crew members Thomas Pesquet of ESA (European Space Agency) and Expedition 51 Station Commander Peggy Whitson of NASA at 6:05 a.m. EDT using the space station’s 57.7-foot (17.6-meter) Canadian-built Canadarm2 robotic arm.

The SS John Glenn Cygnus vehicle counts as Orbital ATK’s seventh cargo delivery flight to the station.

The vehicle is also known alternatively as the Cygnus OA-7 or CRS-7 mission.

Cygnus OA-7 is loaded with 3459 kg (7626 pounds) of science experiments and hardware, crew supplies, spare parts, gear and station hardware to the orbital laboratory in support over 250 research experiments being conducted on board by the Expedition 51 and 52 crews. The total volumetric capacity of Cygnus exceeds 27 cubic meters.

Blastoff of SS John Glenn on Orbital ATK OA-7 resupply mission bound for the ISS atop ULA Atlas V rocket from Space Launch Complex 41 at Cape Canaveral Air Force Station, FL on April 18, 2017. Credit: Julia Bergeron

The Orbital ATK SS John Glenn Cygnus is the 2nd US cargo ship to launch to the ISS this year following the SpaceX Dragon CRS-10 mission in February – as I reported here.