Refugee children learn astronomy in the Netherlands


This video from the Netherlands says about itself:

Kickstart the Universe: UNAWE crowdfund to send astronomy educational resources around the globe

14 May 2014

Leiden University‘s Universe Awareness educational programme has launched an innovative Kickstarter crowdfunding campaign to share the educational toolkit, Universe in a Box, with underprivileged communities around the world.

From Leiden University in the Netherlands:

Refugee children explore cosmos with Universe Awareness

14 October 2016

In September 2016, the educational programme Universe Awareness (UNAWE) implemented a series of educational activities at Basisschool De Verrekijker, a primary school for refugee children in Katwijk, the Netherlands.

In this month-long astronomy project, more than 180 children and their teachers engaged in astronomy educational activities. For instance, participants learned about the planets of our Solar System and created their own spaceships. This astronomy-themed month was concluded on 30 September with a visit from the NOVA Mobile Planetarium and a family day where parents and siblings could see what the students learned and created.

Universe Awareness

Since early 2016, UNAWE has implemented several initiatives with refugee children in the Leiden region. UNAWE aims to inspire young children around the world with astronomy, science and technology, because astronomy embodies a unique combination of scientific and cultural aspects. Learning about our amazing cosmos offers a special perspective on our place in the Universe that encourages a sense of global citizenship and tolerance.

Discovery Club

In the first half of 2016, UNAWE implemented Discovery Club, an after-school Science, Technology, Engineering, Arts and Mathematics (STEAM) programme developed to inspire, educate and entertain children and parents in refugee centres. Discovery Club held weekly sessions with a group of around 30 children. According to Tibisay Sankatsing Nava, Project Manager at UNAWE, there was an enormous willingness to help by volunteers within, as well as outside the Sterrewacht: ‘With the volunteers we managed to provide fun, hands-on science activities for the kids every Saturday. The children needed continuity: their lives had been disrupted and the weekly activities provided both a fun learning opportunity and stability while they were in the emergency center.’

Saturn’s moon Dione, underground ocean?


This video says about itself:

NASA’s Cassini Finds Hidden Ocean on Saturn’s Moon Dione

3 October 2016

New gravity data from recent Cassini flybys of the giant planet suggest that Dione’s crust floats on an ocean 62 miles below the surface, and may harbor microbial life.

From Science News:

Saturn’s moon Dione might harbor an underground ocean

by Christopher Crockett

2:14pm, October 7, 2016

A Saturnian satellite joins the club of moons with oceans. A subsurface sea might hide beneath the icy crust of Dione, a moon of Saturn, researchers report online September 28 in Geophysical Research Letters. That puts Dione in good company alongside Enceladus (another moon of Saturn), several moons of Jupiter and possibly even Pluto.

Dione’s ocean is about 100 kilometers below the surface and is roughly 65 kilometers deep, Mikael Beuthe, a planetary scientist at the Royal Observatory of Belgium in Brussels, and colleagues report. They inferred the ocean’s presence from measurements of Dione’s gravity made by the Cassini spacecraft, which has been in orbit around Saturn since 2004.

10 times more galaxies than previously thought, new research


This video says about itself:

13 October 2016

Since Edwin Hubble discovered that the Milky Way is not the only galaxy in the Universe, astronomers try to find out how many of them are there. This new Hubblecast focusses on the question “How many galaxies are there?” including the new numbers achieved in 2016.

From the Hubblesite:

October 13, 2016 10:00 AM (EDT)

News Release Number: STScI-2016-39

Hubble Reveals Observable Universe Contains 10 Times More Galaxies Than Previously Thought

The universe suddenly looks a lot more crowded, thanks to a deep-sky census assembled from surveys taken by NASA’s Hubble Space Telescope and other observatories.

Astronomers came to the surprising conclusion that there are at least 10 times more galaxies in the observable universe than previously thought.

The results have clear implications for galaxy formation, and also helps shed light on an ancient astronomical paradox — why is the sky dark at night?

In analyzing the data, a team led by Christopher Conselice of the University of Nottingham, U.K., found that 10 times as many galaxies were packed into a given volume of space in the early universe than found today. Most of these galaxies were relatively small and faint, with masses similar to those of the satellite galaxies surrounding the Milky Way. As they merged to form larger galaxies the population density of galaxies in space dwindled. This means that galaxies are not evenly distributed throughout the universe’s history, the research team reports in a paper to be published in The Astrophysical Journal.

“These results are powerful evidence that a significant galaxy evolution has taken place throughout the universe’s history, which dramatically reduced the number of galaxies through mergers between them — thus reducing their total number. This gives us a verification of the so-called top-down formation of structure in the universe,” explained Conselice.

One of the most fundamental questions in astronomy is that of just how many galaxies the universe contains. The landmark Hubble Deep Field, taken in the mid-1990s, gave the first real insight into the universe’s galaxy population. Subsequent sensitive observations such as Hubble‘s Ultra Deep Field revealed a myriad of faint galaxies. This led to an estimate that the observable universe contained about 200 billion galaxies. The new research shows that this estimate is at least 10 times too low.

Conselice and his team reached this conclusion using deep-space images from Hubble and the already published data from other teams. They painstakingly converted the images into 3-D, in order to make accurate measurements of the number of galaxies at different epochs in the universe’s history. In addition, they used new mathematical models, which allowed them to infer the existence of galaxies that the current generation of telescopes cannot observe. This led to the surprising conclusion that in order for the numbers of galaxies we now see and their masses to add up, there must be a further 90 percent of galaxies in the observable universe that are too faint and too far away to be seen with present-day telescopes. These myriad small faint galaxies from the early universe merged over time into the larger galaxies we can now observe.

“It boggles the mind that over 90 percent of the galaxies in the universe have yet to be studied. Who knows what interesting properties we will find when we discover these galaxies with future generations of telescopes? In the near future, the James Webb Space Telescope will be able to study these ultra-faint galaxies,” said Conselice.

The decreasing number of galaxies as time progresses also contributes to the solution for Olbers’ paradox (first formulated in the early 1800s by German astronomer Heinrich Wilhelm Olbers): Why is the sky dark at night if the universe contains an infinity of stars? The team came to the conclusion that indeed there actually is such an abundance of galaxies that, in principle, every patch in the sky contains part of a galaxy. However, starlight from the galaxies is invisible to the human eye and most modern telescopes due to the other known factors that reduce visible and ultraviolet light in the universe. Those factors are the reddening of light due to the expansion of space, the universe’s dynamic nature, and the absorption of light by intergalactic dust and gas. All combined, this keeps the night sky dark to our vision.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C.

Origin of the universe, evolution of life, new film


This video from the USA says about itself:

Voyage of Time IMAX® Trailer

30 June 2016

Voyage of Time: The IMAX Experience, a 40-minute, giant-screen adventure narrated by Brad Pitt, which immerses audiences directly into the story of the universe and life itself, will be shown exclusively in IMAX® theatres. For more info, visit here.

From Science News:

‘Voyage of Time’ is Terrence Malick’s ode to life

Film offers an artistic take on science

By Erin Wayman

4:38pm, October 7, 2016

Condensing billions and billions and billions of years into a 45-minute film is a tall order. But director Terrence Malick took on the challenge with Voyage of Time. The film, now playing in IMAX theaters, surveys the 13.8-billion-year history of the universe and even looks eons into the future when we — life on Earth, the planet and the entire solar system — are gone.

Starting with the Big Bang, Voyage of Time progresses through highlights of the past, with a central focus on the evolution of life. Malick, best known for directing visually rich dramas such as The Thin Red Line and The Tree of Life, presents breathtaking cinematography, using locales such as Hawaii’s lava-oozing Kilauea volcano as stand-ins for the past. Stunning visualizations and special effects bring to life the formation of the planets, the origin of the first cells, the demise of the sun and other events that scientists can only imagine.

The film marks Malick’s first attempt at documentary filmmaking. If you can call it that. Viewers hoping for a David Attenborough–style treatment of the subject matter will be disappointed. The film is more evocative, with moody scenes that provide little explication. And what narration (by Brad Pitt) there is tends to be philosophical rather than informative.

Serious science enthusiasts may find some reasons to quibble with the movie. For one, it’s hard to grasp the true immenseness and scale of cosmic time. With so much screen time devoted to the evolution of life, many viewers may not realize just how relatively recent a phenomenon it is. After the Big Bang, more than 9 billion years passed before Earth began to form. It took many hundred thousand more years before the first microbes emerged.

Malick’s treatment of evolution may also rankle some viewers. At times, the narration seems to imply life was destined to happen, with the young, barren Earth just waiting around for the first seeds of life to take root. At other times, the narration imbues evolution with purpose. Pitt notes, for instance, that perfecting a leaf took eons. Yet perfection is something evolution neither achieves nor strives for — it’s a process that lacks intentionality.

These critiques aside, Malick sought to tell an accurate story, enlisting an accomplished group of scientists as advisers, including Lee Smolin of the Perimeter Institute for Theoretical Physics in Waterloo, Canada. Smolin says he was impressed with the end result. “It’s a very unusual film,” he says, likening it to a visual poem or piece of art.

And that’s probably the best mindset to watch Voyage of Time: Just sit back, soak in the dazzling visuals and contemplate the wonders of nature.

Rosetta spaceship’s comet mission ending tomorrow


This video says about itself:

5 August 2016

Animation visualising Rosetta’s two-year journey around Comet 67P/Churyumov–Gerasimenko.

The animation begins on 31 July 2014, during Rosetta’s final approach to the comet after its ten-year journey through space. The spacecraft arrived at a distance of 100 km on 6 August whereupon it gradually approached the comet and entered initial mapping orbits that were needed to select a landing site for Philae. These observations also enabled the first comet science of the mission. The manoeuvres in the lead up to, during and after Philae’s deployment on 12 November are seen, before Rosetta settled into longer-term science orbits.

In February and March 2015 the spacecraft made several flybys. One of the closest flybys triggered a ‘safe mode’ event that forced it to retreat temporarily until it was safe to gradually draw closer again. The comet’s increased activity in the lead up to and after perihelion in August 2015 meant that Rosetta remained well beyond 100 km distances for several months.

In June 2015, contact was restored with Philae again – albeit temporary, with no permanent link able to be maintained, despite a series of dedicated trajectories flown by Rosetta for several weeks.

Following perihelion, Rosetta performed a dayside far excursion some 1500 km from the comet, before re-approaching to closer orbits again, enabled by the reduction in the comet’s activity. In March–April 2016 Rosetta went on another far excursion, this time on the night side, followed by a close flyby and orbits dedicated to a range of science observations.

The animation finishes at 9 August 2016, before the details of the end of mission orbits were known. A visualisation of the trajectories leading to the final descent to the surface of the comet on 30 September will be provided once available.

The trajectory shown in this animation is created from real data, but the comet rotation is not. An arrow indicates the direction to the Sun as the camera viewpoint changes during the animation.

From Science News:

So long, Rosetta: End is near for comet orbiter

Spacecraft’s legacy will live on after it lands on comet 67P, shuts down for good

By Christopher Crockett

5:30am, September 29, 2016

Rosetta is about to take its final bow.

On September 30, the comet orbiter will wrap up its nearly 26-month visit to comet 67P/Churyumov-Gerasimenko by touching down on the surface and then shutting down. Before sending its last signal to Earth, Rosetta will snap pictures and gather data all the way to the end, collecting some of the most detailed looks ever at a comet.

“Every time you look at a body and increase the resolution … it’s another world,” says Jessica Sunshine, a planetary scientist at the University of Maryland in College Park. “It’s going to be very interesting to see what this place looks like.”

After more than 10 years in space, Rosetta arrived at 67P on August 6, 2014 (SN: 9/6/14, p. 8). About three months later, a lander named Philae detached from the orbiter and dropped to the comet’s surface. It was a rough landing: Philae bounced twice and nicked a ridge before coming to rest on its side in the shadow of a cliff. With insufficient sunlight to charge its battery, Philae went to sleep about 60 hours later, though not before getting some pictures of its new home.

Unlike Philae, the orbiter was never designed to land on the comet. Despite meeting the ground at a walking pace of about 3 kilometers per hour, Rosetta’s landing — described as a “controlled impact” by mission scientists — will probably snap pieces off of the spacecraft.

“Feelings are mixed,” says mission lead Matt Taylor of the European Space Research and Technology Center in Noordwijk, the Netherlands. “Sadness that this is over, but great joy on what [we’ve] achieved.”

Before bidding the spacecraft adieu, here’s a look back at five mission highlights.

  1.  One surprise came right away when researchers got their first good gander at the comet. Described as resembling a rubber duck, comet 67P has two distinct lobes. Some planetary scientists suspect that 67P was once two comets that smooshed together (SN: 10/31/15, p. 17).
  2.  Comets are not just big balls of ice, as once thought. Towering cliffs, dusty dunes, shadowy pits — the landscape on 67P is a hodgepodge of terrains, some scarred by erosion, others blanketed under seasonal flows of fine dust (SN: 2/21/15, p. 6). Comets “are much more dynamic than a lot of surfaces in the solar system,” Sunshine says.
  3. Water on 67P is unlike Earth’s, suggesting that comets provided little help in bringing H2O to our planet (SN: 1/10/15, p. 8). The ratio of deuterium (a heavy form of hydrogen) to hydrogen in 67P’s water is roughly three times that on Earth. Comets as a whole, however, exhibit a large range in this ratio, implying comets have diverse origins.
  4. Comet 67P carts around a cocktail of chemicals that includes oxygen and noble gases, both indicators of a birthplace that was cold and far from the sun (SN: 11/28/15, p. 6). Organic molecules are prevalent as well. While asteroids probably delivered the bulk of Earth’s water, “comets do have complex organics and could have brought those to Earth and provided the seeds of life,” Taylor says.
  5. The interior of the comet is quite porous, which suggests that 67P was assembled gently 4.6 billion years ago (SN: 8/22/15, p. 13). That means the comet’s building blocks weren’t altered by forceful collisions, which supports the long-standing idea that comets are time capsules that preserve samples from the solar system’s formative years.

Comet science doesn’t end with Rosetta. Ground-based telescopes will continue to study them from afar, and next year NASA will consider proposals for flying a spacecraft to a comet, plucking a piece off the surface and bringing it back to Earth.

“As for Rosetta data, there is loads of it,” Taylor says. “There is decades of work to do. So Rosetta isn’t over — it’s just begun.”

Rosetta spacecraft lands on comet, ends mission, by Christopher Crockett, 8:19am, September 30, 2016: here.

Jupiter moon Europa spouting water


This video says about itself:

26 September 2016

NASA has announced that a team using the Hubble Space Telescope has spotted possible water vapor plumes on Jupiter’s moon Europa.

From Science News:

Europa spouting off again

Hubble images of plumes on Jupiter’s icy moon revive talk of hidden ocean

By Christopher Crockett

5:18pm, September 26, 2016

Jupiter’s moon Europa might once again be venting water into space, further supporting the idea that an ocean hides beneath its thick shell of ice, researchers reported September 26 at a news conference.

Plumes erupting from the moon’s surface, silhouetted against background light from Jupiter, appear in several images taken by the Hubble Space Telescope in early 2014. The geysers — presumably of water vapor or ice particles — showed up in the same location as an eruption captured by Hubble in 2012 (SN: 1/25/14, p. 6). The eruptions also appear to be intermittent, appearing in only three out of 10 images. Material hovering over the moon’s southern hemisphere and absorbing ultraviolet light coming from Jupiter made the plumes visible.

“The plumes are a sign that we may be able to explore the ocean without having to drill through unknown miles of ice,” said William Sparks, an astronomer at the Space Telescope Science Institute in Baltimore. “We presume it to be water or ice particles because that’s what Europa is made of and those molecules do absorb at the wavelengths we observed,” he said. Future spacecraft could plow through the plumes and sample the water to better understand its chemistry and look for by-products of life.

First ever failed supernova discovered?


This video says about itself:

Hydrogen River Between Galaxies Breaks the Rules | Space News

28 February 2014

Scientists using the Green Bank Telescope have observed what they describe as a river of neutral hydrogen streaming into the Galaxy NGC 6946. The researchers conclude that this tenuous filament of gas is providing the necessary fuel for the high rate of star formation in the spiral galaxy.

From Science News:

Vanished star may be first known failed supernova

Despite no signs of massive explosion, black hole now marks stellar grave

By Christopher Crockett

6:00am, September 20, 2016

A star that mysteriously disappeared might be the first confirmed case of a failed supernova, a star that tried to explode but couldn’t finish the job. A newborn black hole appears to have been left behind to snack on the star’s remains.

In 2009, a star in the galaxy NGC 6946 flared up over several months to become over 1 million times as bright as the sun. Then, it seemed to vanish. While the star could just be hiding behind a wall of dust, new observations with the Hubble Space Telescope, reported online September 6 at arXiv.org, strongly suggest that the star did not survive. A faint trickle of infrared light, however, emanates from where the star used to be. The remnant glow probably comes from debris falling onto a black hole that formed when the star died, write Caltech astronomer Scott Adams and colleagues.

Black holes are typically thought to form in the aftermath of a supernova, the explosive death of a massive star. But multiple lines of evidence have recently hinted that not all heavyweights go out with a bang. Some stars might skip the supernova and collapse into a black hole. Until now, though, evidence that this happens has been either spotty or indirect.

“This is the first really solid observational evidence for a failed supernova,” says Elizabeth Lovegrove, an astronomer at the University of California, Santa Cruz. “Some supernovas really do fail and this is what they look like.”

This attempt at a supernova, first observed with the Large Binocular Telescope in Arizona, occurred about 19 million light-years away in the constellation Cygnus. Only one other known star — a yellow supergiant that faded away in 2010 — is suspected to be a failed supernova, though there’s not enough data to say for certain.

When a star at least eight times as heavy as the sun runs out of thermonuclear fuel, it can no longer support its own weight. Gas crashes down on the star’s core, bounces and sends a shock wave racing back toward the surface that tears the star apart. Some stars might be so massive that the shock wave doesn’t have enough oomph to push against the onrush of collapsing star stuff. The shock fizzles, the supernova fails and the core gathers enough mass to collapse into a black hole, possibly taking the rest of the star down with it.

If the dying star is a red supergiant — a ruddy orb that can be over 1,000 times as wide as the sun — it might give a signal before vanishing. As the core collapses, it releases an enormous amount of gravitational energy. A second shock wave ripples up through the star — not powerful enough for an explosion, but enough to burp off the loosely held outer layers of the supergiant and expose the feeding black hole.

That’s exactly what Adams and colleagues think they saw. Hubble images from before 2009 reveal a star about 25 to 30 times as massive as the sun sitting where the flash of light came from. The star doesn’t show up in images taken since the eruption. Neither the brightness of the flash, the rate at which the brightness evolved nor the amount of light coming from there now fully matches other types of stellar incidents, such as a collision between a pair of stars or the violent outbursts that accompany some aging supermassive stars.

If the star did give birth to a black hole, X-rays may be radiating from debris spiraling down its gravitational throat. Adams and collaborators are waiting on observations from the space-based Chandra X-ray Observatory to check that idea. They also continue to monitor what’s left of the star. The star might still be there, hiding within a shell of dust expelled during the 2009 eruption. If that’s the case, it should become visible again in the coming years as the cloak dissipates.