A Third of All Galaxy Clusters Have Gone Unnoticed Until Now

By Chelsea Gohd | January 11, 2019 5:13 pm
galaxy cluster

The galaxy cluster Abell 370, as seen by the Hubble Space Telescope. (Credit: ESA/Hubble/NASA)

Hidden Clusters

The universe is far from homogenous. Rather, stars, and the galaxies that contain them, clump together in some places, brought together by their shared gravitational attraction. Astronomers have historically found clusters of galaxies in the sky to be relatively easy to spot, as they’re extremely large and bright. But one new study suggests that a third of all galaxy clusters have been hiding undiscovered out in the cosmos.

Scientists estimate that very little of the mass of a galaxy cluster is actually made of galaxies themselves. Much of the mass probably comes from the hot gas that floats between the galaxies, and far more is probably from dark matter. This means that the most obvious feature of a galaxy cluster is actually responsible for very little of its mass. It’s a disparity that has likely hidden an enormous number of less traditional galaxy clusters throughout the universe.

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CATEGORIZED UNDER: Space & Physics, top posts
MORE ABOUT: cosmology, dark matter

Neurons From People With Autism Grow Differently, Scientists Find

By Lacy Schley | January 11, 2019 4:49 pm
Fluorescent imaging of neuronal cells stained in red and green.

A two-dimensional culture of cortical neurons, stained in red and green, grown from induced pluripotent stem cells created from volunteers’ skin cells. (Credit: Salk Institute)

Researchers announced this week that they may have helped illuminate another small piece of the puzzle that is autism spectrum disorder (ASD), a developmental disorder that can impact social communication and behavior.

In a paper published in the journal Nature Neuroscience, an international team of neuroscientists described a process that used participants’ skin cells to eventually grow neurons in petri dishes. Their observations of the neurons’ growth could help unravel some of the mysteries about early brain development in ASD.

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CATEGORIZED UNDER: Mind & Brain, top posts

NASA’s New World-hunting Satellite Just Found Two More Exoplanets

By Jake Parks | January 11, 2019 4:40 pm
HD 21749b

The discovery and confirmation of the sub-Neptune exoplanet HD 21749b (middle) makes it the third small planet discovered by TESS so far, and many more are likely on the way. (Credit: NASA/GSFC/MIT News)

Within just a few months of beginning its primary science mission, NASA’s planet-hunting Transiting Exoplanet Survey Satellite (TESS) already has identified over 50 exoplanet candidates. Now, TESS has discovered and confirmed one of the densest sub-Neptune (meaning smaller than Neptune) planets found so far: HD 21749b.

As an added bonus, the newly confirmed world just so happens to be the longest-period confirmed TESS planet discovered to date. Furthermore, it also seems to have a planetary sibling that is surprisingly similar to Earth.

A Hefty sub-Neptune

Located about 52 light-years from Earth in the direction of the Southern Hemisphere constellation Reticulum, HD 21749b is a strange world that orbits a bright, orange dwarf star once every 36 days.

Like many exoplanets discovered so far, HD 21749b sits very close to its star. Specifically, it orbits at a distance of just 0.2 AU (1 AU is the Earth-Sun distance of 93 million miles [150 million km]), so the newfound planet sits twice as close to its host star as Mercury is to the Sun.

Though HD 21749b is only about 3 times the size of Earth, it’s a whopping 23 times as massive. This means that the world has an overall density of 5.7 grams per cubic centimeter. (For reference, that’s significantly denser than diamond and titanium, and about half the density of lead; however, with an average density of 5.5 g/cm3, Earth is also pretty dense.)


By utilizing just three months of data from TESS, researchers have discovered the small, yet massive planet HD 21749b, which orbits a rather Sun-like star. (Credit: NASA/MIT/TESS)

Importantly, according to the research paper, which is available on the pre-print website arXiv.org, “the density of HD 21749b indicates it is likely surrounded by a substantial atmosphere.” Unfortunately, the authors also point out the HD 21749b likely is not an ideal target for future atmospheric follow-up observations with the upcoming James Webb Space Telescope (JWST).

Finally, HD 21749b is also pretty cool for a planet its size. The world sports temperatures that hover around 300 degrees Fahrenheit (150 Celsius), which is just a bit too hot for liquid water to exist on its surface. 

A Boiling Earth-sized World

In addition to finding HD 21749b, TESS also recently discovered an Earth-sized world orbiting the same system’s host star. However, since the planet has yet to be confirmed, it still holds the moniker TOI 186.02, which stands for “TESS Object of Interest 186.02.”

At roughly 80 percent the mass and 90 percent the size of Earth, if confirmed, TOI 186.02 would be the very first Earth-sized planet discovered by TESS.

However, just because a planet is about the same size and mass as Earth, it doesn’t mean it’s truly a fitting Earth analog. For example, TOI 186.02 has a very short orbital period of just 7.8 days and little is known about its composition or potential atmosphere. Furthermore, the world experiences temperatures of around 800 degrees Fahrenheit (430 Celsius), making it more akin to Venus than Earth.

No matter whether TOI 186.02 is truly a fitting Earth-like exoplanet or not, these new discoveries show that the multi-planet system HD 21749 is ripe for future study and exploration, so be sure to stay tuned.

The newly discovered planets were announced during this week’s 233rd annual meeting of the American Astronomical Society, held in Seattle, Washington.


[This article originally appeared on Astronomy.com]

CATEGORIZED UNDER: Space & Physics, top posts
MORE ABOUT: exoplanets

Recreating the Intense Conditions of the Earth’s Mantle Solves A Long-standing Geological Mystery

By Bill Andrews | January 11, 2019 4:26 pm
inner earth

The various layers of the inner Earth. (Credit: Ellen Bronstayn/Shutterstock)

Science is never exactly easy, but it’s especially tough when you can’t see, touch or even really interact with your subject. Consider the plight of a geophysicist interested in the makeup and structure of Earth’s interior. Without being able to dig up a sample of our planet’s ultrahot, ultra-pressurized mantle, how can they figure out what makes our planet work?

The answer, in part, is seismic waves. When the ground shakes, as in an earthquake, the vibrations go through and interact with all the materials in their way. This can provide scientists with a means of imaging all those materials, allowing them to virtually peer beneath the surface.

But sometimes that’s not enough. If the models tell you the vibrations — analogous to sound waves in some cases — should travel at a certain speed, but the data show they don’t, you’re left with an anomaly. Something’s wrong, but without somehow recreating the incredible conditions hundreds of miles below the surface, how can you figure out what?

Just such an issue has been plaguing geophysicists studying the Earth’s innards, who’ve noticed that vibrations from earthquakes traveling through the mantle have been going slower than they should be.

At least until now, that is. According to a Nature paper this week, a team of Japanese scientists figured out what was wrong just by recreating those crazy conditions after all.

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CATEGORIZED UNDER: Environment, top posts
MORE ABOUT: earth science, physics

Conditions for Life Might Exist On The New Planet Discovered Around Barnard’s Star

By Alison Klesman | January 10, 2019 4:53 pm
An artist’s interpretation of what Barnard’s star b, a super-Earth recently discovered just six light-years from Earth, may look like. (Credit: ESO/M. Kornmesser)

An artist’s interpretation of what Barnard’s star b, a super-Earth recently discovered just six light-years from Earth, may look like. (Credit: ESO/M. Kornmesser)

Late last year, astronomers announced that they’d found a super-Earth around Barnard’s star – one of the closest suns to our own. The discovery of a planet just six light-years away was enough to excite astronomers and the public alike. However, the researchers who found the planet said that they suspected the icy world couldn’t support life.

But now, a group of astronomers are saying such pessimism may be premature. On Earth, geothermal vents produce heat and create unique environments where life thrives in places otherwise difficult to eke out a living – like the frigid, dark deep of the oceans. The team says similar processes could be at work on this world, which is officially cataloged as Barnard b.

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CATEGORIZED UNDER: Space & Physics, top posts

SNAPSHOT: Hubble Takes Second-most Detailed Image Ever

By Alison Mackey | January 10, 2019 4:41 pm
triangulum galaxy

The Triangulum galaxy is seen here in the second-largest image ever taken by Hubble. (Credit: NASA, ESA, and M. Durbin, J. Dalcanton, and B. F. Williams (University of Washington))

Hubble just released its second-largest image ever: the Triangulum Galaxy, and it’s a stunner. While Andromeda has been holding the top spot since being imaged back in 2015, this ~665 million-pixel composite is nothing to sneeze at, clocking in at a staggering 34,372 x 19,345 pixels. All told that adds up to 665 million pixels.

Also known as Messier 33, 40 billion stars make up this spiral galaxy, which is faintly visible by naked eye under a dark sky as a small smudge in the constellation Triangulum (the triangle.) This image spans 14,500 light-years, composed of shots taken between February 2017 and 2018 by the famous space telescope’s Advanced Camera for Surveys. The Triangulum Galaxy is small by cosmic standards, at about half the diameter of the Milky Way and a quarter of the diameter of the Andromeda galaxy. Still, the astronomers estimate there are anywhere between 10 and 15 millions stars contained in this image.

Eat your heart out, David Bowman — this thing is FULL of stars!


Find more great science imagery on our Instagram page.

CATEGORIZED UNDER: Space & Physics, top posts
MORE ABOUT: cosmology, stargazing, stars

SpaceX’s Crew Dragon Might Launch Next Month

By Chelsea Gohd | January 10, 2019 4:23 pm
falcon 9 crew capsule

The Falcon 9 rocket sits with the Crew Dragon capsule and the new astronaut walkway on launch pad 39A. (Credit: SpaceX)

Crew Dragon Launch

In just about a month, SpaceX’s first Crew Dragon spacecraft might launch for the first time on an uncrewed orbital test flight to the International Space Station, SpaceX CEO Elon Musk stated on Jan 5 on Twitter.

Previously, SpaceX had suggested that the launch would take place Jan 17. After Musk said that the launch was about a month away, NASA confirmed in a statement today that an uncrewed test flight will take place no sooner than February. Still, no official new launch date has been announced. NASA said that these delays are due to the team needing additional time “to complete hardware testing and joint reviews.”

But, as SpaceNews suggested, it’s possible that the U.S. government shutdown, which furloughed about 95 percent of NASA’s civil servant workforce, could be partially responsible.

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CATEGORIZED UNDER: Space & Physics, top posts

In a First, Astronomers Capture Birth of Black Hole or Neutron Star

By Chelsea Gohd | January 10, 2019 4:15 pm
A look at The Cow (approximately 80 days after explosion) from the W.M. Keck Observatory in Maunakea, Hawaii. The Cow is nestled in the CGCG 137-068 galaxy, 200 million light years from Earth. (Credit: Raffaella Margutti/Northwestern University)

A look at The Cow (approximately 80 days after explosion) from the W.M. Keck Observatory in Maunakea, Hawaii. The Cow is nestled in the CGCG 137-068 galaxy, some 200 million light-years from Earth. (Credit: Raffaella Margutti/Northwestern University)

Some 200 million years ago, not long after dinosaurs first appeared on Earth, a star collapsed in a nearby galaxy. The star’s collapse triggered an ultra-bright explosion that sent radiation racing across the cosmos. The light finally reached earthly skies this past summer, forming a strange, new beacon in the constellation Hercules.

The ATLAS survey’s twin telescopes in Hawaii, were the first to spot the exploding star on June 17, 2018. And astronomers from around the world – including an international team of 45 co-authors from 33 different institutions – soon turned their telescopes and attention to studying the mysterious compact object created in the aftermath. By combining radio waves, gamma-rays, and X-rays, the team suspects the object, officially named AT2018cow and informally called “The Cow,” is likely a black hole or neutron star surrounded by swirling stellar debris.

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CATEGORIZED UNDER: Space & Physics, top posts

Termites’ Engineering Skills Help Protect Tropical Rainforests From Drought

By Roni Dengler | January 10, 2019 1:55 pm
termite construction rainforest drought

Termites scamper about on the rainforest floor in Borneo. (Credit: corlaffra/shutterstock)

Termites are minuscule scourges to homeowners, but the wood-chomping critters are also masterful engineers. And now an international team of researchers has found that these construction skills actually help protect tropical rainforests from drought. The insects have an outsized impact on forest soils by helping control moisture in the dirt, a critical component to forest health that climate change and human impacts increasingly threaten. The results also suggest termites could buffer tropical rainforests from drought in the future.

“We previously thought termites were important in tropical rainforests, but we didn’t know how important, particularly during drought,” said Louise Ashton, an ecologist at the University of Hong Kong, who led the new work.

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CATEGORIZED UNDER: Living World, top posts

Blue Tooth Reveals Woman Scribe From Middle Ages

By Megan Schmidt | January 10, 2019 9:54 am

Lapis lazuli pigment entrapped within the dental calculus on the lower jaw of a medieval woman. (Credit: Christina Warinner)

For the medieval Christian, opening an illuminated religious text was like opening a window into the sacred. These lavishly decorated books contained teachings of the church and helped deepen the beliefs of the faithful. The luxurious materials used in their creation glittered in the light, offering an elevated spiritual experience.

A brilliant blue pigment known as ultramarine, a color often associated with holiness and royalty in art, was reserved for special features of this artwork — such as the robe of the Virgin Mary. Derived from the lapis lazuli stone mined only in Afghanistan, the pigment was once considered more precious than gold.

Now, researchers say they’ve discovered one of the most prized pigments in art history in a peculiar place — in the dental plaque of a woman buried at a monastery at the Church of St. Peter in Dalhaim, Germany around 1000-1200 AD. The researchers say the find represents the “earliest direct evidence that religious women in Germany used ultramarine pigment,” challenging gendered ideas about the role of women in creating one of the highest forms of art in medieval times.

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CATEGORIZED UNDER: Living World, top posts
MORE ABOUT: archaeology

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