Posted on by Nancy Atkinson

A ‘Cosmic Miracle’: Indications Of Early Forming ‘Direct Collapse’ Black Hole Seen

An image based on a supercomputer simulation of the cosmological environment where primordial gas undergoes the direct collapse to a black hole. Credit: Aaron Smith/TACC/UT-Austin.
An image based on a supercomputer simulation of the cosmological environment where primordial gas undergoes the direct collapse to create black holes. Credit: Aaron Smith/TACC/UT-Austin.

Astronomers have been finding some extremely old supermassive black holes, ones that formed when the Universe was quite young. But they were puzzled at how a black hole could grow to such tremendous size when the Universe itself was just a toddler.

Astronomers have now found a unique set of conditions were present half a billion years after the Big Bang that allowed these monster black holes to form. An unusual source of intense radiation created what are called “direct-collapse black holes.”

“It’s a cosmic miracle,” said Volker Bromm of The University of Texas at Austin, who worked with several astronomers on the finding. “It’s the only time in the history of the universe when conditions are just right for them to form.”

The conventional understanding of how black holes form is called the accretion theory, where an extremely massive star collapses and black hole “seeds” are built from the collapse by pulling in gas from their surroundings and by mergers of smaller black holes. But that process takes a long time, much longer than the time these quickly forming black holes were around. Plus, the early universe didn’t have the quantities of gas and dust needed for supermassive black holes to grow to their gigantic size.

The new findings suggest instead that some of the first black holes formed directly when a cloud of gas collapsed, bypassing any other intermediate phases, such as the formation and subsequent destruction of a massive star.

This artist's illustration depicts a possible "seed" for the formation of a supermassive black hole, that is an object that contains millions or even billions of times the mass of the Sun. In the artist's illustration, the gas cloud is shown as the wispy blue material, while the orange and red disk is showing material being funneled toward the growing black hole through its gravitational pull. Credit: X-ray: NASA/CXC/Scuola Normale Superiore/Pacucci, F. et al, Optical: NASA/STScI; Illustration: NASA/CXC/M.Weiss.
This artist’s illustration depicts a possible “seed” for the formation of a supermassive black hole, that is an object that contains millions or even billions of times the mass of the Sun. In the artist’s illustration, the gas cloud is shown as the wispy blue material, while the orange and red disk is showing material being funneled toward the growing black hole through its gravitational pull. Credit: X-ray: NASA/CXC/Scuola Normale Superiore/Pacucci, F. et al, Optical: NASA/STScI; Illustration: NASA/CXC/M.Weiss.

Of course, like any black hole, these “direct collapse” black holes can’t be seen. But there was strong evidence for their existence, as they are needed to power the highly luminous quasars detected in the young universe. A quasar’s great brightness comes from matter spiraling into a supermassive black hole, heating to millions of degrees, creating jets that shine like beacons across the Universe. But since the accretion theory doesn’t explain supermassive black holes in extremely distant — and therefore young — universe, astronomers couldn’t explain the quasars either. This has been called “the quasar seed problem.”

“The quasars observed in the early universe resemble giant babies in a delivery room full of normal infants,” said Avi Loeb from the Harvard-Smithsonian Center for Astrophysics, who worked with Bromm. “One is left wondering: what is special about the environment that nurtured these giant babies? Typically the cold gas reservoir in nearby galaxies like the Milky Way is consumed mostly by star formation.”

But In 2003, Bromm and Loeb came up with a theoretical idea to get an early galaxy to form a supermassive seed black hole, by suppressing the otherwise prohibitive energy input from star formation. They called the process “direct collapse.”

“Begin with a “primordial cloud of hydrogen and helium, suffused in a sea of ultraviolet radiation,” Bromm said. “You crunch this cloud in the gravitational field of a dark-matter halo. Normally, the cloud would be able to cool, and fragment to form stars. However, the ultraviolet photons keep the gas hot, thus suppressing any star formation. These are the desired, near-miraculous conditions: collapse without fragmentation! As the gas gets more and more compact, eventually you have the conditions for a massive black hole.”

This set of cosmic conditions appears to have only existed in the very early universe, and this process does not happen in galaxies today.

To test their theory, Bromm, Loeb and their colleague Aaron Smith started studying a galaxy called CR7, identified by a Hubble Space Telescope survey called COSMOS as being around at less than 1 billion years after the Big Bang.

David Sobral of the University of Lisbon had made follow-up observations of CR7 with some of the world’s largest ground-based telescopes, including Keck and the VLT. These uncovered some extremely unusual features in the light signature coming from CR7. Specifically, the Lyman-alpha hydrogen line was several times brighter than expected. Remarkably, the spectrum also showed an unusually bright helium line.

“Whatever is driving this source is very hot — hot enough to ionize helium,” Smith said, about 100,000 degrees Celsius.

These and other unusual features in the spectrum meant that it could either be a cluster of primordial stars or a supermassive black hole likely formed by direct collapse.

Smith ran simulations for both scenarios and while the star cluster scenario “spectacularly failed,” Smith said, the direct collapse black hole model performed well.

Also, earlier this year, researchers using combined data from the Chandra X-ray Observatory, Hubble Space Telescope, and Spitzer Space Telescope to identify these possible black hole seeds. They found two objects, both of these matched the theoretical profile in the infrared data. (read their paper here.)

It seems astronomers are “converging on this model,” Smith said, for solving the quasar seed problem and the early black hole conundrum.

Stay tuned.

Bromm, Loeb and Smith’s work is published in the journal Monthly Notices of the Royal Astronomical Society.

Sources:
RAS, Harvard-Smithsonian CfA, Press release for NASA’s detection of direct collapse black holes earlier this year.

Posted on by Nancy Atkinson

First Detection of Water Clouds Outside Our Solar System

Artist's conception of how WISE 0855 might appear if viewed close-up in infrared light. Artwork by Joy Pollard, Gemini Observatory/AURA.

Brown dwarfs – those not-quite-a-planet and not-quite-a-star objects – are intriguing oddities that are too low in mass to burn hydrogen, but are more massive than planets. They only emit a faint amount of light, so they are hard to detect, making scientists unsure of how many of them might be out there in our galaxy.

But astronomers have been keeping an eye one particular brown dwarf known called WISE 0855. Just 7.2 light-years from Earth, it is the coldest known object outside of our Solar System and is just barely visible at infrared wavelengths. But with some crafty spectroscopic observing techniques, astronomers have now determined this object has some exciting characteristics: its atmosphere is full of clouds of water vapor. This is the first time water clouds have been detected outside of our Solar System.

“It’s five times fainter than any other object detected with ground-based spectroscopy at this wavelength,” said Andrew Skemer, assistant professor of astronomy and astrophysics at UC Santa Cruz and the first author on a paper on WISE 0855 published in Astrophysical Journal Letters (paper is available on arXiv here). “Now that we have a spectrum, we can really start thinking about what’s going on in this object. Our spectrum shows that WISE 0855 is dominated by water vapor and clouds, with an overall appearance that is strikingly similar to Jupiter.”

This brown dwarf’s full name is WISE J085510.83-071442.5, but we’re among friends, so it’s W0855 for short. It has about five times the mass of Jupiter and is the coldest brown dwarf ever detected, with an average temperature of about 250 degrees Kelvin, or minus 10 degrees F, minus 20 C. That makes it nearly as cold as Jupiter, which is 130 degrees Kelvin.

“WISE 0855 is our first opportunity to study an extrasolar planetary-mass object that is nearly as cold as our own gas giants,” Skemer said.

Skemer and his team used the Gemini-North telescope in Hawaii and the Gemini Near Infrared Spectrograph to observe WISE 0855 over 13 nights for a total of about 14 hours. Skemer was part of a team that studied this object in 2014 found tentative indications of water clouds based on very limited photometric data. Skemer said obtaining a spectrum (which separates the light from an object into its component wavelengths) was the only way to detect this object’s molecular composition.

A video about the 2014 discovery and study of WISE 0855:

WISE 0855 is too faint for conventional spectroscopy at optical or near-infrared wavelengths, but the team took up a challenge and looked at the thermal emissions from the object at wavelengths in a narrow window around 5 microns.

“I think everyone on the research team really believed that we were dreaming to think we could obtain a spectrum of this brown dwarf because its thermal glow is so feeble,” said Skemer. WISE 0855, is so cool and faint that many astronomers thought it would be years before a spectrum could be obtained. “I thought we’d have to wait until the James Webb Space Telescope was operating to do this,” Skemer said.

This spectroscopic view provided a glimpse into the environment of WISE 0855’s atmosphere. With the data in hand, the researchers then developed atmospheric models of the equilibrium chemistry for a brown dwarf at 250 degrees Kelvin and calculated the resulting spectra under different assumptions, including cloudy and cloud-free models. The models predicted a spectrum dominated by features resulting from water vapor, and the cloudy model yielded the best fit to the features in the spectrum of WISE 0855.

While the spectra of this object are strikingly similar to Jupiter, WISE 0855 appears to have a less turbulent atmosphere.

“The spectrum allows us to investigate dynamical and chemical properties that have long been studied in Jupiter’s atmosphere, but this time on an extrasolar world,” Skemer said.

The scientists say WISE 0855 looks more similar to Jupiter than any exoplanet yet discovered, which is especially intriguing since the Juno mission has just begun its exploration at the giant world. Jupiter, along with the other gas planets in our Solar System, all have clouds and storms, although Jupiter’s clouds are mainly made of ammonia with lower level clouds perhaps containing water. One of Juno’s goals is to determine the global water abundance at Jupiter.

Sources: UC Santa Cruz, Gemini

Posted on by Nancy Atkinson

Jupiter’s Magnetosphere Will Blow Your Mind While it Kills Your Spacecraft

Jupiter has an extremely powerful magnetic field. Ganymede has one, too, and is the only moon with one. Jupiter's envelops Ganymede's and their interactions are just part of the pair's complicated relationship. Image Credit: NASA Goddard Space Flight Center.

Jupiter is a huge planet, but its magnetosphere is mind-blowingly massive. It extends out to nearly 5 million kilometers (3 million miles) wide on average, 150 times wider than Jupiter itself and almost 15 times wider than the Sun, making it one of the largest structures in the Solar System.

“If you were to look up into the night sky and if we could see the outline of Jupiter’s magnetosphere, it would be about the size of the Moon in our sky,” said Jack Connerney, deputy principal investigator and head of the Juno mission magnetometer team. “It’s a very large feature in our Solar System, and it’s a pity we can’t see it.”

But the Juno spacecraft is about to change our understanding of Jupiter’s magnetosphere and allow scientists to “see” for the first time Jupiter’s magnetic field.

And today, NASA announced that Juno has entered Jupiter’s magnetic field. Listen to the video below as the spacecraft gathered data as it crossed the bow shock:

A magnetosphere is the area of space around a planet that is controlled by the planet’s magnetic field. The stronger the magnetic field, the larger the magnetosphere. It is estimated that Jupiter’s magnetic field is about 20,000 times stronger than Earth’s.

Jupiter has spectacular aurora, such as this view captured by the Hubble Space Telescope. Auroras are formed when charged particles in the space surrounding the planet are accelerated to high energies along the planet's magnetic field. Credit: NASA, ESA, and J. Nichols (University of Leicester)
Jupiter has spectacular aurora, such as this view captured by the Hubble Space Telescope. Auroras are formed when charged particles in the space surrounding the planet are accelerated to high energies along the planet’s magnetic field. Credit: NASA, ESA, and J. Nichols (University of Leicester)

Magnetic fields are produced by what are known as dynamos – an electric current created from the convection motion of a planet’s interior. Earth’s magnetic field is generated by its circulating core of molten iron and nickel. But what creates Jupiter’s dynamo? Is it like Earth’s or could it be very different? Jupiter consists predominantly of hydrogen and helium, and it is currently unknown if there is a rocky core at the center of the planet.

“With Jupiter, we don’t know what material is producing the planet’s magnetic field,” said Jared Espley, Juno program scientist for NASA Headquarters, “What material is present and how deep down it lies is one of the questions Juno is designed to answer.”

Juno has a pair of magnetometers to basically look inside the planet. The magnetometers will allow scientists to map Jupiter’s magnetic field with high accuracy and observe variations in the field over time. The instruments will be able to show how the magnetic field is generated by dynamo action deep in the planet’s interior, providing the first look at what the magnetic field looks like from the surface of the dynamo where it is generated.

“The best way to think of a magnetometer is like a compass,” said Connerney. “Compasses record the direction of a magnetic field. But magnetometers expand on that capability and record both the direction and magnitude of the magnetic field.”

But Jupiter presents a lot of problems as far as being nice to instruments. Trapped within the magnetosphere are charged particles from the Sun that form intense radiation belts around the planet. These belts are similar to the Earth’s Van Allen belts, but are many millions of times stronger.

To help protect the spacecraft and instrument electronics, Juno has a radiation vault about the size of a car trunk made of titanium that limits the radiation exposure to Juno’s command and data handling box (the spacecraft’s brain), power and data distribution unit (its heart) and about 20 other electronic assemblies. But the instruments themselves need to be outside of the vault in order to make their observations.

Workers place the special radiation vault for NASA's Juno spacecraft onto the propulsion module. Image credit: NASA/JPL-Caltech/LMSS
Workers place the special radiation vault for NASA’s Juno spacecraft onto the propulsion module. Image credit: NASA/JPL-Caltech/LMSS

The magnetometer sensors are on a boom attached to one of the solar arrays, placing them about 40 feet (12 meters) from the body of the spacecraft. This helps ensure that the rest of the spacecraft does not interfere with the magnetometer.
But there are other ways to help limit the amount of radiation exposure, at least in the first part of the mission.

Scientists designed a path that takes Juno around Jupiter’s poles so that the spacecraft spends the least amount of time possible in those blistering radiation belts around Jupiter’s equator. Engineers also used designs for electronics already approved for the Martian radiation environment, which is harsher than Earth’s, though not as harsh as Jupiter’s.

That elliptical orbit — between radiation belt and the planet — also puts the spacecraft very close to Jupiter, about 5,000 km above the cloud tops, enabling a close-up look at this amazing planet.

“This is our first opportunity to do very precise, high-accuracy mapping of the magnetic field of another planet,” Connerney said. “We are going to be able to explore the entire three-dimensional space around Jupiter, wrapping Jupiter in a dense net of magnetic field observations completely covering the sphere.”

By studying Jupiter’s magnetosphere, scientists will gain a better understanding about how Jupiter’s magnetic field is generated. They also hope to measure how fast Jupiter is spinning, determine whether the planet has a solid core, and learn more about Jupiter’s formation.

“It’s always incredible to be the first person in the world to see anything,” Connerney said, “and we stand to be the first to look down upon the dynamo and see it clearly for the first time.”

Further reading: Juno mission page, NASA article on Juno’s magnetometer.

Posted on by Nancy Atkinson

Bezos Is Building A House For His Big Brother

Artist concept of Blue Origin's 750,000 square foot spacecraft factory. Credit: Blue Origin.

Blue Origin and its founder Jeff Bezos do a little one-upmanship on the old saying, “go big or go home.” With the groundbreaking of their new orbital vehicle manufacturing complex, they are going big AND going home. The new facility will be located near Kennedy Space Center in Florida and will house Blue Origin’s orbital launch vehicle, which Bezos has sometimes referred to as “Very Big Brother.” The new facility has a planned grand opening of December 2017.

Site preparation for Blue Origin's new orbital vehicle manufacturing complex in Florida. Credit: Blue Origin.
Site preparation for Blue Origin’s new orbital vehicle manufacturing complex in Florida. Credit: Blue Origin.

Blue Origin announced the plans for the complex in September 2015, and bulldozers started clearing ground this week (June 28, 2016). The facility will be where Blue Origin manufactures, processes, integrates and tests its rockets.

“It’s exciting to see the bulldozers in action,” Bezos wrote in an email update. “We’re clearing the way for the production of a reusable fleet of orbital vehicles that we will launch and land, again and again.”

Bezos said the 750,000 square foot (70,000 sq. meter) building will be “custom-built from the ground up” and will enable “large scale friction stir welding and automated composite processing equipment,” among other things.

The entire launch vehicle will be manufactured in this new facility except for the engines, the BE-4 — which Blue Origin says will be flight qualified by 2017 — and are currently produced in Blue Origin’s Kent, Washington facility. But they plan to build a new, larger engine production facility to accommodate their projected need for higher production rates, and they will conduct a site selection process for that facility later this year.

Another artist concept of Blue Origin's orbital vehicle manufacturing complex in Florida. Credit: Blue Origin.
Another artist concept of Blue Origin’s orbital vehicle manufacturing complex in Florida. Credit: Blue Origin.

Another little one-upmanship: Blue Origin’s new facility will best SpaceX’s main factory, which is about 550,000 square feet (51,000 sq. meters). SpaceX’s Hawthorne, California building was originally used by Northrup Aircraft to build 747 fuselages (although, SpaceX’s total campus of buildings in Hawthorne is over 1.6 million square feet.)

Very Big Brother (VBB) will get an official name at some point, but it will be a vertical takeoff, vertical landing (VTVL) system, like Blue Origin’s smaller suborbital New Shepard rocket. The plan is to have VBB’s lower stage be reusable and the upper stage be expendable.

For launches, Blue Origin will share Cape Canaveral Air Force Station’s Space Launch Complex 36 with Google Lunar X PRIZE team Moon Express (MoonEx).

The New Shepard launching from its facility in West Texas. Image: Blue Origin
The New Shepard rocket launching from its facility in West Texas. Image: Blue Origin
Posted on by Nancy Atkinson

NASA Brings Back the X-Plane, and This One’s Electric

An artist's concept of NASA's X-57 Maxwell aircraft, a new electric X-plane that is quieter, more efficient and more environmentally friendly. Credits: NASA Langley/Advanced Concepts Lab, AMA, Inc

While NASA has had a long and storied history of building and testing experimental aircraft – called X-planes — it has been almost a decade since the space agency has developed any new aircraft. But an initiative announced earlier this year as part of the new budget has NASA back designing, building and flying a new series of X-planes, with the goal of creating more “green” aviation technologies that can then be utilized by the aeronautics industry.

NASA unveiled the first plane in the new X series, an electric aircraft with 14 motors integrated into a new wing design. This experimental airplane has been designated the X-57, with the nickname of “Maxwell,” to honor James Clerk Maxwell, the 19th century Scottish physicist who did groundbreaking work in electromagnetism.

“With the return of piloted X-planes to NASA’s research capabilities – which is a key part of our 10-year-long New Aviation Horizons initiative – the general aviation-sized X-57 will take the first step in opening a new era of aviation,” said NASA Administrator Charlie Bolden, speaking at an annual forum of theAmerican Institute of Aeronautics and Astronautics (AIAA).

This artist's concept of NASA's X-57 Maxwell aircraft shows the plane's specially designed wing and 14 electric motors. Credits: NASA Langley/Advanced Concepts Lab, AMA, Inc.
This artist’s concept of NASA’s X-57 Maxwell aircraft shows the plane’s specially designed wing and 14 electric motors. Credits: NASA Langley/Advanced Concepts Lab, AMA, Inc.

Other new X-plane designs include larger transport-scale aircraft that will use less fuel and create less noise, and a business-jet-sized supersonic vehicle that burns low carbon bio-fuels and generates only quiet sonic booms that people on the ground will barely hear. The main goals of the new X-planes will be to demonstrate how airliners can burn half the fuel, saving airline companies money, while generating 75 percent less pollution during each flight as compared to now. They’ll also be much quieter than today’s jets.

The X-57 Maxwell has newly designed long, skinny wings embedded with 14 electric motors – 12 on the leading edge for take offs and landings, and one larger motor on each wing tip for use while at cruise altitude. The idea is that distributing electric power across a number of motors integrated with an aircraft will result in a five-time reduction in the energy required for a private plane to cruise at 175 mph.

The Bell X-1, in which Chuck Yeager “broke” the sound barrier in 1947. Credit: NASA
The Bell X-1, in which Chuck Yeager “broke” the sound barrier in 1947. Credit: NASA

NASA’s first X-plane was the X-1, which in 1947 became the first airplane to fly faster than the speed of sound. It was flown by Chuck Yeager and was featured in the book and movie “The Right Stuff.” While many of the aircraft were well known — like the X-15 that became the fastest piloted aircraft of the X-plane program — other aircraft were developed clandestinely. Other experimental aircraft included research on lifting bodies and other wing designs or unique engines like the scramjet. Other experimental aircraft didn’t carry the “X” designation, like the Navy’s D-558-II Skyrocket, but was flown by Scott Crossfield in 1953 to become the first airplane to travel twice the speed of sound, or Mach 2.

“Dozens of X-planes of all shapes, sizes and purposes have followed – all of them contributing to our stature as the world’s leader in aviation and space technology,” said Jaiwon Shin, associate administrator for NASA’s Aeronautics Research Mission Directorate. “Planes like the X-57, and the others to come, will help us maintain that role.”

Further reading: NASA

Posted on by Nancy Atkinson

Second Gravitational Wave Source Found By LIGO

This image depicts two black holes just moments before they collided and merged with each other, releasing energy in the form of gravitational waves. Image credit: Numerical Simulations: S. Ossokine and A. Buonanno, Max Planck Institute for Gravitational Physics, and the Simulating eXtreme Spacetime (SXS) project. Scientific Visualization: T. Dietrich and R. Haas, Max Planck Institute for Gravitational Physics.

Lightning has struck twice – maybe three times – and scientists from the Laser Interferometer Gravitational-wave Observatory, or LIGO, hope this is just the beginning of a new era of understanding our Universe. This “lightning” came in the form of the elusive, hard-to-detect gravitational waves, produced by gigantic events, such as a pair of black holes colliding. The energy released from such an event disturbs the very fabric of space and time, much like ripples in a pond. Today’s announcement is the second set of gravitational wave ripples detected by LIGO, following the historic first detection announced in February of this year.

“This collision happened 1.5 billion years ago,” said Gabriela Gonzalez of Louisiana State University at a press conference to announce the new detection, “and with this we can tell you the era of gravitational wave astronomy has begun.”

LIGO’s first detection of gravitational waves from merging black holes occurred Sept. 14, 2015 and it confirmed a major prediction of Albert Einstein’s 1915 general theory of relativity. The second detection occurred on Dec. 25, 2015, and was recorded by both of the twin LIGO detectors.

While the first detection of the gravitational waves released by the violent black hole merger was just a little “chirp” that lasted only one-fifth of a second, this second detection was more of a “whoop” that was visible for an entire second in the data. Listen in this video:

“This is what we call gravity’s music,” said González as she played the video at today’s press conference.

While gravitational waves are not sound waves, the researchers converted the gravitational wave’s oscillation and frequency to a sound wave with the same frequency. Why were the two events so different?

From the data, the researchers concluded the second set of gravitational waves were produced during the final moments of the merger of two black holes that were 14 and 8 times the mass of the Sun, and the collision produced a single, more massive spinning black hole 21 times the mass of the Sun. In comparison, the black holes detected in September 2015 were 36 and 29 times the Sun’s mass, merging into a black hole of 62 solar masses.

The scientists said the higher-frequency gravitational waves from the lower-mass black holes hit the LIGO detectors’ “sweet spot” of sensitivity.

“It is very significant that these black holes were much less massive than those observed in the first detection,” said Gonzalez. “Because of their lighter masses compared to the first detection, they spent more time—about one second—in the sensitive band of the detectors. It is a promising start to mapping the populations of black holes in our universe.”

An aerial view of LIGO Hanford. (Credit: Gary White/Mark Coles/California Institue of Technology/LIGO/NSF).
An aerial view of LIGO Hanford. (Credit: Gary White/Mark Coles/California Institue of Technology/LIGO/NSF).

LIGO allows scientists to study the Universe in a new way, using gravity instead of light. LIGO uses lasers to precisely measure the position of mirrors separated from each other by 4 kilometers, about 2.5 miles, at two locations that are over 3,000 km apart, in Livingston, Louisiana, and Hanford, Washington. So, LIGO doesn’t detect the black hole collision event directly, it detects the stretching and compressing of space itself. The detections so far are the result of LIGO’s ability to measure the perturbation of space with an accuracy of 1 part in a thousand billion billion. The signal from the lastest event, named GW151226, was produced by matter being converted into energy, which literally shook spacetime like Jello.

LIGO team member Fulvio Ricci, a physicist at the University of Rome La Sapienzaa said there was a third “candidate” detection of an event in October, which Ricci said he prefers to call a “trigger,” but it was much less significant and the signal to noise not large enough to officially count as a detection.

But still, the team said, the two confirmed detections point to black holes being much more common in the Universe than previously believed, and they might frequently come in pairs.

“The second discovery “has truly put the ‘O’ for Observatory in LIGO,” said Albert Lazzarini, deputy director of the LIGO Laboratory at Caltech. “With detections of two strong events in the four months of our first observing run, we can begin to make predictions about how often we might be hearing gravitational waves in the future. LIGO is bringing us a new way to observe some of the darkest yet most energetic events in our universe.”

LIGO is now offline for improvements. Its next data-taking run will begin this fall and the improvements in detector sensitivity could allow LIGO to reach as much as 1.5 to two times more of the volume of the universe compared with the first run. A third site, the Virgo detector located near Pisa, Italy, with a design similar to the twin LIGO detectors, is expected to come online during the latter half of LIGO’s upcoming observation run. Virgo will improve physicists’ ability to locate the source of each new event, by comparing millisecond-scale differences in the arrival time of incoming gravitational wave signals.

In the meantime, you can help the LIGO team with the Gravity Spy citizen science project through Zooniverse.

Sources for further reading:
Press releases:
University of Maryland
Northwestern University
West Virginia University
Pennsylvania State University
Physical Review Letters: GW151226: Observation of Gravitational Waves from a 22-Solar-Mass Binary Black Hole Coalescence
LIGO facts page, Caltech

For an excellent overview of gravitational waves, their sources, and their detection, check out Markus Possel’s excellent series of articles we featured on UT in February:

Gravitational Waves and How They Distort Space

Gravitational Wave Detectors and How They Work

Sources of Gravitational Waves: The Most Violent Events in the Universe

Posted on by Nancy Atkinson

Gorgeous Photos of Earth and the Night Sky: TWAN Photo Contest Winners Announced

'Northern Lights above Lofoten,' a photo taken by Alex Conu, won first prize in the 'Against the Lights' category in the 2016 International Earth & Sky Photo Contest. The image was taken from a mountaintop in Lofoten Islands, Norway. Credit and copyright: Alex Conu.

The winners of the 7th annual Earth & Sky Photo Contest have been announced, and wow, these images are absolutely stunning! The contest really highlights the beauty of the night sky, and its mission is to spread the message to cut down on light pollution while helping to preserve the last remaining natural night environments and night skies in the world. The contest was organized by The World at Night (TWAN) and other sister organizations.

“The sky above us is an essential part of our nature, a heritage for us and other species on this planet,” said TWAN founder and contest chair, Babak Tafreshi.”The contest main goal is to present the night sky in this broader context that helps preserving the natural night sky by reconnect it with our modern life.”

See more winning photos below:

The second place winner in the ‘Against the Light’ category is Carlo Zanandrea from Italy for "All that Glitters is not Gold" taken in December 2015 showing constellation Orion rising over lights and fog in the province of Treviso in northeastern Italy. Credit and copyright: Carlo Zanandrea.
The second place winner in the ‘Against the Light’ category is Carlo Zanandrea from Italy for “All that Glitters is not Gold” taken in December 2015 showing constellation Orion rising over lights and fog in the province of Treviso in northeastern Italy. Credit and copyright: Carlo Zanandrea.

Just last week, a group of Italian and American scientists unveiled a new global atlas of light pollution, and sadly, they said the results show the Milky Way is “but a faded memory to one-third of humanity and 80 percent of Americans.”

“We’ve got whole generations of people in the United States who have never seen the Milky Way,” said Chris Elvidge, a scientist with NOAA’s National Centers for Environmental Information. “It’s a big part of our connection to the cosmos — and it’s been lost.”

These photos from Earth & Sky Contest really display that important connection, with people and places on Earth being a big part of many of the images – the classic definition of “TWAN-style” photography. According to the contest theme of “Dark Skies Importance,” the submitted photos were judged in two categories: “Beauty of The Night Sky” and “Against the Lights.”

“The selected images are those most effective in impressing public on both how important and delicate the starry sky is as an affecting part of our nature, and also how bad the problem of light pollution has become,” TWAN said in their press release. “Today, most city skies are virtually devoid of stars. Light pollution (excessive light that scatters to the sky instead of illuminating the ground) not only is a major waste of energy, it also obscures the stars, disrupts ecosystems and has adverse health effects.”

"The Photographer" by Nicholas Roemmelt from Austria is the second place winner in the 'Beauty of the Night Sky category, taken in March 2015 in Stockiness, Iceland. Credit and copyright: Nicholas Roemmelt
“The Photographer” by Nicholas Roemmelt from Austria is the second place winner in the ‘Beauty of the Night Sky category, taken in March 2015 in Stockiness, Iceland. Credit and copyright: Nicholas Roemmelt

The winning images were chosen on their “aesthetic merit and technical excellence,” said David Malin of the judging panel, who is well-known pioneer in scientific astrophotography. “We believe they accurately reflect the state of the art in TWAN-style photography. The competition encourages photographers with imagination to push their cameras to their technical limits, and to produce eye-catching images that appear perfectly natural and are aesthetically pleasing.”

This photo, "Viking Lights" by Adam Woodworth from USA, won in the composite section of the ‘Beauty of the Night Sky’ category, where frames of various exposure or focus settings are blended. This image was captured in Newfoundland, Canada in June, 2015. Credit and copyright: Adam Woodworth.
This photo, “Viking Lights” by Adam Woodworth from USA, won in the composite section of the ‘Beauty of the Night Sky’ category, where frames of various exposure or focus settings are blended. This image was captured in Newfoundland, Canada in June, 2015. Credit and copyright: Adam Woodworth.
In the photo sequence submissions, the winner in the Beauty category is "Total Solar Eclipse from Svalbard" by Thanakrit Santikunaporn from Thailand. He captured the eclipse phases every 3 minutes over frozen landscape of Svalbard, Norway on March 20, 2015. Credit and copyright: Thanakrit Santikunaporn.
In the photo sequence submissions, the winner in the Beauty category is “Total Solar Eclipse from Svalbard” by Thanakrit Santikunaporn from Thailand. He captured the eclipse phases every 3 minutes over frozen landscape of Svalbard, Norway on March 20, 2015. Credit and copyright: Thanakrit Santikunaporn.

The contest was open to anyone of any age, anywhere in the world; to both professional and amateur/hobby photographers. It has been an annual event since 2009 (initially for the International Year of Astronomy) by TWAN, the National Optical Astronomy Observatory, and Global Astronomy Month from Astronomers Without Borders. The contest supports efforts of the International Dark Sky Association (IDA) and other organizations that seek to preserve the night sky.

The images were taken in 57 countries and territories including Algeria, Antarctica, Australia, Austria, Bahamas, Belgium, Bolivia, Brazil, Canada, China, Colombia, Croatia, Czech Republic, Egypt, England, Estonia, Finland, France, Germany, Greece, Guatemala, Guam, Hungary, Iceland, India, Indonesia, Iran, Ireland, Italy, Japan, Jordan, Kenya, Lithuania, Madagascar, Malaysia, Malta, Morocco, Norway, New Zealand, Paraguay, Peru, Philippines, Poland, Reunion (France), Romania, Russia, Scotland, Sri Lanka, South Africa, Spain, South Africa, Sri Lanka, Sweden, Switzerland, Tanzania, Thailand, Ukraine, and USA.

See all the images and more information about them at TWAN. Click on each image for larger versions. A larger version of the lead image can be found here.

You can see the global atlas of light pollution here, which was created from data from the NOAA/NASA Suomi National Polar-orbiting Partnership satellite and calibrated by thousands of ground observations.

And here’s a video that includes all the winning images:

Posted on by Nancy Atkinson

Watch Mercury Transit the Sun in Multiple Wavelengths

A composite image of the May 9, 2016 transit of Mercury across the face of the Sun, as seen by the Solar Dynamics Observatory. Credit: NASA's Goddard Space Flight Center/SDO/Genna Duberstein

On May 9, 2016, Mercury passed directly between the Sun and Earth. No one had a better view of the event than the space-based Solar Dynamics Observatory, as it had a completely unobstructed view of the entire seven-and-a-half-hour event! This composite image, above, of Mercury’s journey across the Sun was created with visible-light images from the Helioseismic and Magnetic Imager on SDO, and below is a wonderful video of the transit, as it includes views in several different wavelenths (and also some great soaring music sure to stir your soul).

Mercury transits of the Sun happen about 13 times each century, however the next one will occur in only about three and a half years, on November 11, 2019. But then it’s a long dry spell, as the following one won’t occur until November 13, 2032.

Make sure you check out the great gallery of Mercury transit images from around the world compiled by our David Dickinson.

Posted on by Nancy Atkinson

Dark Moon Discovered Orbiting Dwarf Planet Makemake

This Hubble Space Telescope image reveals the first moon ever discovered around the dwarf planet Makemake. The tiny 100 mile-wide moon, nicknamed MK 2, is located just above Makemake in this image, and is barely visible because it is almost lost in the glare of the very bright dwarf planet. Credit: NASA, ESA, A. Parker and M. Buie (Southwest Research Institute), W. Grundy (Lowell Observatory), and K. Noll (NASA GSFC)

Planetary scientists using the Hubble Space Telescope have spotted a dark mini-moon orbiting the distant dwarf planet Makemake. The moon, nicknamed MK 2, is roughly 160 km (100 miles) wide and orbits about 20,000 km (13,000 miles) from Makemake. Makemake is 1,300 times brighter than its moon and is also much larger, at 1,400 km (870 miles) across, about 2/3rd the size of Pluto.

“Our discovery of the Makemakean moon means that every formally-designated Kuiper Belt dwarf planet has at least one moon!” said Alex Parker on Twitter. Parker, along with Mark Buie, both from the Southwest Research Institute, led the same team that found the small moons of Pluto in 2005, 2011, and 2012, and they used the same Hubble technique to find MK 2. NASA says Hubble’s Wide Field Camera 3 has the unique ability to see faint objects near bright ones, and together with its sharp resolution, allowed the scientists to pull the moon out from bright Makemake’s glare.

Artist impression of Makemake and its moon. Credit: NASA, ESA, and A. Parker (Southwest Research Institute).
Artist impression of Makemake and its moon. Credit: NASA, ESA, and A. Parker (Southwest Research Institute).

Previous searches for moons around Makemake came up empty, but Parker said their analysis shows the moon has a very dark surface and it is also in a nearly edge-on orbit, which made it very hard to find.

This moon might be able to provide more details about Makemake, such as its mass and density. For example, when Pluto’s moon Charon was discovered in 1978, astronomers were able to measure Charon’s orbit and then calculate the mass of Pluto, which showed Pluto’s mass was hundreds of times smaller than originally estimated.

“Makemake is in the class of rare Pluto-like objects, so finding a companion is important,” Parker said. “The discovery of this moon has given us an opportunity to study Makemake in far greater detail than we ever would have been able to without the companion.”

Parker also said the discovery of a moon for Makemake might solve a long-standing mystery about the dwarf planet. Thermal observations of Makemake by the Spitzer and Herschel space observatories seemed to show the bright world had some darker, warmer material on its surface, but other observations couldn’t confirm this.

Parker said perhaps the dark material isn’t on Makemake’s surface, but instead is in orbit. “I modeled the emission we expect from Makemake’s moon, and if the moon is very dark, it accounts for most previous thermal measurements,” he said on Twitter.

The researchers will need more Hubble observations to make accurate measurements to determine if the moon’s orbit is elliptical or circular, and this could help determine its origin. A tight circular orbit means that MK 2 probably formed from a collision between Makemake and another Kuiper Belt Object. If the moon is in a wide, elongated orbit, it is more likely to be a captured object from the Kuiper Belt. Many KBOs are covered with very dark material, so that might explain the dark surface of MK 2.

Read the team’s paper.
HubbleSite info on the discovery

Posted on by Nancy Atkinson

Incredible Hand-Drawn Animations Explain How Spacecraft Work

A sample of the detailed drawings of Stanley VonMedvey that explain how spacecraft work. Credit and copyright: Stanley VonMedvey. Used by permission.

Freelance animator and storyboard artist Stanley VonMedvey has started using his remarkable talents to create short videos to explain a pretty complex topic: how spacecraft work. He’s made two so far and they are wonderfully concise, clear and easy to understand. Plus his hand-drawn animations are incredible.

Here’s the first one that caught my eye, about the space shuttle and the concept of reusability:

VonMedvey describes himself as “completely obsessed with and fascinated by space exploration,” and he wants to share what he’s learned over the years about spaceflight.

He’d like the opportunity and resources to make more videos, and has started a Patreon page to help in this process. Right now, he creates the videos on his own (using the time-honored home-recording technique of draping a blanket over his head) in his home officee.

“I’d like to make a lot more videos,” he writes on Patreon, “explaining things like Hohmman transfers and laser propulsion and the construction techniques of O’Neill cylinders. I want to make long form videos (2-3 minutes) that explain a general idea, and short form videos (30 seconds) that cover a single word, like “ballistics” or “reaction control”.

The second video he’s done covers expendable launch vehicles:

Enjoy these great videos and if you’d like to see more, consider supporting his work. See more of his drawings at his website.