Astronomy

The SOCIETY for POPULAR ASTRONOMY

Electronic News Bulletin No. 463 2018 February 18

Here is the latest round-up of news from the Society for Popular
Astronomy.


COMPOSITION OF TRAPPIST-1 PLANETS
ESO

The seven Earth-size planets of TRAPPIST-1 are all mostly made of rock, with some having the potential to hold more water than the Earth. The planets' densities, now known much more precisely than before, suggest that some of them could have up to 5 per cent of their mass in water -- which is 250 times more than the oceans on Earth. The form that water would take on TRAPPIST-1 planets would depend on the amount of heat they receive from their star, which is a mere 9 per cent as massive as our Sun. Planets closest to the star are more likely to have water in the form of atmospheric vapour, while those farther away may have water frozen on their surfaces as ice. TRAPPIST-1e is the rockiest planet of them all, but still is believed potentially to have some liquid water. Astronomers now know more about TRAPPIST-1 than about any other planetary system apart from our own. Since the extent of the TRAPPIST system was recognized in 2017 February, researchers have been working hard to characterize the planets better and to collect more information about them. The new study offers better estimates than were available previously for the planets' densities. The TRAPPIST name comes from the Transiting Planets and Planetesimals Small Telescope in Chile, which discovered two of the seven planets we know of today --announced in 2016. The Spitzer space telescope, in collaboration with ground-based telescopes, confirmed those planets and discovered the other five in the system. Since then, the Kepler space telescope has also observed the TRAPPIST-1 system, and Spitzer began a new programme of 500 additional hours of TRAPPIST-1 observations, which will conclude in March. The new body of data has helped the authors of the study to paint a clearer picture of the system than ever before -- although there is still much more to learn about TRAPPIST-1.

The TRAPPIST-1 planets huddle so close to one another that a person standing on the surface of one of them would have a spectacular view of the neighbouring planets in the sky. Those planets would sometimes appear larger than the Moon looks to an observer on Earth. They may also be tidally locked, meaning that the same side of the planet is always facing the star, with each side in perpetual day or night. Although the planets are all
closer to their star than Mercury is to the Sun, TRAPPIST-1 is such a cool
star that some of its planets could still, in theory, hold liquid water.
It is impossible to know exactly how each planet looks, because they are so
far away. In our own Solar System, the Moon and Mars have nearly the same density, yet their surfaces appear entirely different. TRAPPIST-1b, the innermost planet, is likely to have a rocky core, surrounded by an atmosphere much thicker than the Earth's. TRAPPIST-1c also probably has a rocky interior, but with a thinner atmosphere than planet b. TRAPPIST-1d is the lightest of the planets -- about three-tenths the mass of the Earth.
Scientists are uncertain whether it has a large atmosphere, an ocean or an
ice layer -- all three of those would give the planet an 'envelope' of
volatile substances, which would make sense for a planet of its density.
Scientists were surprised that TRAPPIST-1e is the only planet in the system
slightly denser than the Earth, suggesting that it may have a relatively
larger iron core than our home planet. Like TRAPPIST-1c, it does not
necessarily have a thick atmosphere, ocean or ice layer -- making those two
planets distinct in the system. It is a mystery why TRAPPIST-1e has a much
rockier composition than the rest of the planets. In terms of size, density
and the amount of radiation it receives from its star, it is the planet that
is most similar to the Earth. TRAPPIST-1f, g and h are far enough from the
host star that water could be frozen as ice on their surfaces. If they have
thin atmospheres, they would be unlikely to contain heavy molecules such as carbon dioxide.

Scientists can calculate the densities of the planets because their orbits
happen to be oriented in such a way that they transit in front of their
star, causing a slight dimming of the starlight. The amount of dimming is
related to the radius of the planet. To get the density, scientists take
advantage of what are called 'transit timing variations'. If there were no
other gravitational forces on a transiting planet, it would always cross in
front of its host star in the same amount of time -- for example, the Earth
orbits the Sun every 365 days. But because the TRAPPIST-1 planets are
packed so close together, they change the timing of one another's 'years'
ever so slightly. Those variations in orbital timing are used to estimate
the planets' masses. Then, mass and radius are used to calculate density.
The next step in exploring TRAPPIST-1 will be with the James Webb space
telescope, which may be able to determine whether these planets have
atmospheres and, if so, what those atmospheres are like. A recent study
using the Hubble telescope found no detection of hydrogen-dominated
atmospheres on planets TRAPPIST-1d, e and f -- another piece of evidence for rocky composition -- although a hydrogen-dominated atmosphere cannot be ruled out for good.

Quote:

---

The scientists argue that, in order to understand how life formed on Earth, we should ignore the surface environments on Mars and focus exploration on hydrothermal deposits. Using infrared data on Mars collected by spacecraft, astronomers can interpret which minerals are there and describe the 'geology' of ancient hydrothermal systems. That type of work is based on laboratory measurements, which provide the necessary mineralogical background with which to interpret spectroscopic data from Mars.

---

Sounds like a valid approach.

Quote:

---

Originally Posted by Dreamwoven

The SOCIETY for POPULAR ASTRONOMY

Electronic News Bulletin No. 463 2018 February 18

Here is the latest round-up of news from the Society for Popular
Astronomy.


COMPOSITION OF TRAPPIST-1 PLANETS
ESO

The seven Earth-size planets of TRAPPIST-1 are all mostly made of rock, with some having the potential to hold more water than the Earth. The planets' densities, now known much more precisely than before, suggest that some of them could have up to 5 per cent of their mass in water -- which is 250 times more than the oceans on Earth. The form that water would take on TRAPPIST-1 planets would depend on the amount of heat they receive from their star, which is a mere 9 per cent as massive as our Sun. Planets closest to the star are more likely to have water in the form of atmospheric vapour, while those farther away may have water frozen on their surfaces as ice. TRAPPIST-1e is the rockiest planet of them all, but still is believed potentially to have some liquid water. Astronomers now know more about TRAPPIST-1 than about any other planetary system apart from our own. Since the extent of the TRAPPIST system was recognized in 2017 February, researchers have been working hard to characterize the planets better and to collect more information about them. The new study offers better estimates than were available previously for the planets' densities. The TRAPPIST name comes from the Transiting Planets and Planetesimals Small Telescope in Chile, which discovered two of the seven planets we know of today --announced in 2016. The Spitzer space telescope, in collaboration with ground-based telescopes, confirmed those planets and discovered the other five in the system. Since then, the Kepler space telescope has also observed the TRAPPIST-1 system, and Spitzer began a new programme of 500 additional hours of TRAPPIST-1 observations, which will conclude in March. The new body of data has helped the authors of the study to paint a clearer picture of the system than ever before -- although there is still much more to learn about TRAPPIST-1.

The TRAPPIST-1 planets huddle so close to one another that a person standing on the surface of one of them would have a spectacular view of the neighbouring planets in the sky. Those planets would sometimes appear larger than the Moon looks to an observer on Earth. They may also be tidally locked, meaning that the same side of the planet is always facing the star, with each side in perpetual day or night. Although the planets are all
closer to their star than Mercury is to the Sun, TRAPPIST-1 is such a cool
star that some of its planets could still, in theory, hold liquid water.
It is impossible to know exactly how each planet looks, because they are so
far away. In our own Solar System, the Moon and Mars have nearly the same density, yet their surfaces appear entirely different. TRAPPIST-1b, the innermost planet, is likely to have a rocky core, surrounded by an atmosphere much thicker than the Earth's. TRAPPIST-1c also probably has a rocky interior, but with a thinner atmosphere than planet b. TRAPPIST-1d is the lightest of the planets -- about three-tenths the mass of the Earth.
Scientists are uncertain whether it has a large atmosphere, an ocean or an
ice layer -- all three of those would give the planet an 'envelope' of
volatile substances, which would make sense for a planet of its density.
Scientists were surprised that TRAPPIST-1e is the only planet in the system
slightly denser than the Earth, suggesting that it may have a relatively
larger iron core than our home planet. Like TRAPPIST-1c, it does not
necessarily have a thick atmosphere, ocean or ice layer -- making those two
planets distinct in the system. It is a mystery why TRAPPIST-1e has a much
rockier composition than the rest of the planets. In terms of size, density
and the amount of radiation it receives from its star, it is the planet that
is most similar to the Earth. TRAPPIST-1f, g and h are far enough from the
host star that water could be frozen as ice on their surfaces. If they have
thin atmospheres, they would be unlikely to contain heavy molecules such as carbon dioxide.

Scientists can calculate the densities of the planets because their orbits
happen to be oriented in such a way that they transit in front of their
star, causing a slight dimming of the starlight. The amount of dimming is
related to the radius of the planet. To get the density, scientists take
advantage of what are called 'transit timing variations'. If there were no
other gravitational forces on a transiting planet, it would always cross in
front of its host star in the same amount of time -- for example, the Earth
orbits the Sun every 365 days. But because the TRAPPIST-1 planets are
packed so close together, they change the timing of one another's 'years'
ever so slightly. Those variations in orbital timing are used to estimate
the planets' masses. Then, mass and radius are used to calculate density.
The next step in exploring TRAPPIST-1 will be with the James Webb space
telescope, which may be able to determine whether these planets have
atmospheres and, if so, what those atmospheres are like. A recent study
using the Hubble telescope found no detection of hydrogen-dominated
atmospheres on planets TRAPPIST-1d, e and f -- another piece of evidence for rocky composition -- although a hydrogen-dominated atmosphere cannot be ruled out for good.

---

Again.They are studying the composition of these planets specially to find an answer for the origin of life.

I thought this article very interesting too:

How does space change the human body?
NASA’s Twins Study sent one identical twin to space for a year, while the other stayed on Earth. Ten separate research projects then tracked how each twin changed.

http://www.astronomy.com/news/2018/0...the-human-body

I only didn´t understand why they sent the twin to space, that wasn´t an astronaut.

It is interesting how they research the differences. They have tried to do really far-reaching studies that explore the differences in great detail.

The SOCIETY for POPULAR ASTRONOMY

Electronic News Bulletin No. 463 2018 February 18

MASSIVE, DENSE SUPER-EARTH DETECTED
Carnegie Institution for Science

A star about 100 light-years away in the constellation Pisces, GJ 9827, has
what may be one of the most massive and dense super-Earth planets detected to date, according to new research. That new information provides evidence to help astronomers understand the process by which such planets form. The GJ 9827 star actually hosts three planets, discovered by the exoplanet-hunting Kepler/K2 mission, and all three are slightly larger than the Earth. That is the size that the Kepler mission found to be most common in the Galaxy with periods between a few and several hundred days. Intriguingly, no planets of that size exist in the Solar System. That makes scientists curious about the conditions under which they form and evolve. One important key to understanding a planet's history is its composition. Are these super-Earths rocky like our own planet? Or do they have solid cores surrounded by large, gassy atmospheres? To try to understand what an exo-planet is made of, scientists need to measure both its mass and its radius, which allow them to determine its bulk density. When quantifying planets in that way, astronomers have noticed a trend. It turns out that planets with radii greater than about 1.7 times that of the Earth have a gassy envelopes, like Neptune's, and those with radii smaller than that are rocky, like ours. Some researchers have proposed that the difference is caused by photo-evaporation, which strips planets of their envelopes of so-called volatiles -- substances like water and carbon dioxide that have low boiling points -- creating smaller-radius planets. But more information is needed to test that theory. That is why GJ 9827's three planets are special -- with radii of 1.64 (planet b), 1.29 (planet c) and 2.08 (planet d), they span the dividing line between super-Earth (rocky) and sub-Neptune (somewhat gassy) planets.

Luckily, scientists have been monitoring GJ 9827 with their Planet-Finding
Spectrograph (PFS), so they were able to constrain the masses of the three
planets with data in hand, rather than having to scramble to get many new
observations of GJ 9827. Usually, if a transiting planet is detected, it
takes months if not a year or more to gather enough observations to measure its mass. Because GJ 9827 is a fairly bright (tenth-magnitude) star, the team already had it in the catalogue of stars that it been monitoring for planets since 2010. The spectrograph was mounted on the Magellan Clay Telescopes at Las Campanas Observatory. The PFS observations indicate that planet b is roughly eight times the mass of the Earth, which would make it one of the most-massive and dense super-Earths yet discovered. The masses for planets c and d are estimated to be about two and a half and four times that of the Earth respectively, although the uncertainty in those two determinations is very high. That information suggests that planet d has a significant volatile envelope, and leaves open the question of whether planet c has a volatile envelope or not. But the better constraint on the mass of planet b suggests that that it is roughly 50% iron. More observations are needed to pin down the compositions of the three planets, but they do seem to be some of the best candidates to test our ideas about how super-Earths form and evolve.

The SOCIETY for POPULAR ASTRONOMY

Electronic News Bulletin No. 463 2018 February 18
PLANETS FOUND IN ANOTHER GALAXY
University of Oklahoma

A team of astronomers has discovered for the first time a population of
planets beyond the Milky Way galaxy. Using microlensing, researchers were able to detect objects in extragalactic systems that range from the mass of the Moon to the mass of Jupiter. The discovery was made using data from the Chandra X-ray Observatory, a telescope in space that is controlled by the Smithsonian Astrophysical Observatory. The small planets are the best candidates for observations by the microlensing technique. While planets are often discovered within the Milky Way using microlensing, the gravitational effect of even small objects can create high magnification, leading to a signature that can be modelled and explained in external galaxies. Until this study, there had been no evidence of planets in other galaxies. The galaxy concerned is 3800 million light-years away, and there is not the slightest chance of observing the planets directly. However, microlensing makes it possible to study them, unveil their presence and even obtain an idea of their masses.

Well, here we are with four new planets. It´s still early to say if the news are good or bad.

That was a poor post I made! Struggling to find something new on the astronomy front.

Idon´t think so. But there really isn´t much to report today.

With the approach of Valentine day, NASA seems to be getting sentimental. But the image is beautiful indeed.

A lonely beauty
Date:
February 14, 2018
Source:
ESA/Hubble Information Centre
Summary:
Beauty, grace, mystery -- this magnificent spiral galaxy has all the qualities of a perfect galactic Valentine. The galaxy NGC 3344 presents itself face-on, allowing astronomers a detailed look at its intricate and elegant structure. And Hubble's ability to observe objects over a wide range of different wavelengths reveals features that would otherwise remain invisible.

https://www.sciencedaily.com/release...0214150237.htm

The SOCIETY for POPULAR ASTRONOMY

Electronic News Bulletin No. 463 2018 February 18

GRAVITATIONAL LENS SETS NEW RECORD
University of Hawaii at Manoa

Extremely distant galaxies are mostly too faint to be seen, even by the
largest telescopes. But nature has a solution: gravitational lensing,
predicted by Einstein and observed many times by astronomers. Now, an
international team of astronomers has discovered one of the most extreme
instances of magnification by gravitational lensing. Using the Hubble
Telescope to survey a sample of huge clusters of galaxies, the team found a
distant galaxy, eMACSJ1341-QG-1, that is magnified 30 times thanks to the
distortion of space-time created by the massive 'foreground' galaxy cluster
dubbed eMACSJ1341.9-2441. The underlying physical effect of gravitational lensing was first confirmed during the solar eclipse of 1919, and can dramatically magnify images of distant celestial sources if a sufficiently massive object lies between the background source and the observers. Galaxy clusters, enormous concentrations of dark matter and hot gas surrounding hundreds or thousands of individual galaxies, all bound by the force of gravity, are valued by astronomers as powerful gravitational lenses. By magnifying the galaxies situated behind them, massive clusters act as natural telescopes that allow scientists to study faint and distant sources that would otherwise be beyond the reach of even the most powerful man-made telescopes. In the present instance, The high magnification of the image provides astronomers with a rare opportunity to investigate the stellar populations of that distant object and, ultimately, to reconstruct its undistorted shape and properties. Although similarly extreme magnifications have been observed before, the discovery sets a record for the magnification of a rare 'quiescent' background galaxy -- one that, unlike our Milky Way, is not forming new stars in giant clouds of cool gas. The team specializes in finding extremely massive clusters that act as natural telescopes and has already discovered many exciting cases of gravitational lensing. This discovery stands out, though, as the huge magnification provided by eMACSJ1341 allows us to study in detail a rare type of galaxy.

I think I understand the concept of Gravitational lensing from the above post.

Quote:

---

By magnifying the galaxies situated behind them, massive clusters act as natural telescopes that allow scientists to study faint and distant sources that would otherwise be beyond the reach of even the most powerful man-made telescopes.

---

This is not clear to me, how these massive clusters act as magnifying lenses.

Well, Einstein predicted this 100 year ago. But I agree, it is still unclear what he meant, as is the way it works.

A quite different kind of research:

A new study shows mankind’s reaction to alien life would be quite positive
News of extraterrestrials would likely generate upbeat attitudes.
"As technology rapidly advances, we’re making astronomical discoveries faster than ever before. Many think it’s just a matter of time before we come across extraterrestrial life and prove that we’re not alone in the universe. So let’s say it actually happens. We uncover or are approached by alien life. Now what? How does the public react? Do our defensive instincts or humble curiosities take over? New research suggests that the general population’s reaction would be quite positive."
http://www.astronomy.com/news/2018/0...quite-positive

I would agree with that conclusion, but the real test will come when we meet intelligent life. No sign of the yet.

I couldn´t agree more, DW!

Improved Hubble yardstick gives fresh evidence for new physics in the universe

Date:
February 22, 2018
Source:
NASA/Goddard Space Flight Center
Summary:
Astronomers have used NASA's Hubble Space Telescope to make the most precise measurements of the expansion rate of the universe since it was first calculated nearly a century ago. Intriguingly, the results are forcing astronomers to consider that they may be seeing evidence of something unexpected at work in the universe.
https://www.sciencedaily.com/release...0222162005.htm

Universe today https://www.universetoday.com has some interesting posts about NASA's SOHO - the Solar and Heliospheric Observatory - https://www.universetoday.com/138664...sun-from-soho/. This website has many different projects, including one when the total eclipse passed over the USA, which gave a prolonged view of solar eclipses.

This is one of the quiet successes of the study of solar eclipses.

"The Solar and Heliospheric Observatory (SOHO) is celebrating 22 years of observing the Sun, marking one complete solar magnetic cycle in the life of our star. SOHO is a joint project between NASA and the ESA and its mission is to study the internal structure of the sun, its extensive outer atmosphere, and the origin of the solar wind.

The activity cycle in the life of the Sun is based on the increase and decrease of sunspots. We’ve been watching this activity for about 250 years, but SOHO has taken that observing to a whole new level."

"Though sunspot cycles work on an 11-year period, they’re caused by deeper magnetic changes in the Sun. Over the course of 22 years, the Sun’s polarity gradually shifts. At the 11 year mark, the orientation of the Sun’s magnetic field flips between the northern and southern hemispheres. At the end of the 22 year cycle, the field has shifted back to its original orientation. SOHO has now watched that cycle in its entirety."

"SOHO is a real success story. It was launched in 1995 and was designed to operate until 1998. But it’s been so successful that its mission has been prolonged and extended several times."

An astroid will pass by Earth really close. There is no danger of it hitting Earth. See http://earthsky.org/space/asteroid-2...oon-mar-2-2018

Yes, it can be seen tomorrow.

I don't know if this is a practical joke or not but I add this post here: http://earthsky.org/space/signal-fro...tars-detected?

"By Karl Glazebrook, Swinburne University of Technology

A signal caused by the very first stars to form in the universe has been picked up by a tiny but highly specialised radio telescope in the remote Western Australian desert.

Details of the detection are revealed in a paper published February 28, 2018, in Nature, and tell us these stars formed only 180 million years after the Big Bang.

It’s potentially one of the most exciting astronomical discoveries of the decade. A second Nature paper, also published February 28, links the finding to possibly the first detected evidence that dark matter, thought to make up much of the universe, might interact with ordinary atoms."

I don´t think it is meant as a joke, DW. I read something about it in the Brazilian news. However no sources were mentioned so I couldn´t trace the information.
Your article mentions two papers published in Nature, which make a more sober approach. I reproduce both abstracts here:

1-An absorption profile centred at 78 megahertz in the sky-averaged spectrum

"Abstract
After stars formed in the early Universe, their ultraviolet light is expected, eventually, to have penetrated the primordial hydrogen gas and altered the excitation state of its 21-centimetre hyperfine line. This alteration would cause the gas to absorb photons from the cosmic microwave background, producing a spectral distortion that should be observable today at radio frequencies of less than 200 megahertz1. Here we report the detection of a flattened absorption profile in the sky-averaged radio spectrum, which is centred at a frequency of 78 megahertz and has a best-fitting full-width at half-maximum of 19 megahertz and an amplitude of 0.5 kelvin. The profile is largely consistent with expectations for the 21-centimetre signal induced by early stars; however, the best-fitting amplitude of the profile is more than a factor of two greater than the largest predictions2. This discrepancy suggests that either the primordial gas was much colder than expected or the background radiation temperature was hotter than expected. Astrophysical phenomena (such as radiation from stars and stellar remnants) are unlikely to account for this discrepancy; of the proposed extensions to the standard model of cosmology and particle physics, only cooling of the gas as a result of interactions between dark matter and baryons seems to explain the observed amplitude3. The low-frequency edge of the observed profile indicates that stars existed and had produced a background of Lyman-α photons by 180 million years after the Big Bang. The high-frequency edge indicates that the gas was heated to above the radiation temperature less than 100 million years later."

2-Possible interaction between baryons and dark-matter particles revealed by the first stars

"Abstract
The cosmic radio-frequency spectrum is expected to show a strong absorption signal corresponding to the 21-centimetre-wavelength transition of atomic hydrogen around redshift 20, which arises from Lyman-α radiation from some of the earliest stars1,2,3,4. By observing this 21-centimetre signal—either its sky-averaged spectrum5 or maps of its fluctuations, obtained using radio interferometers6,7—we can obtain information about cosmic dawn, the era when the first astrophysical sources of light were formed. The recent detection of the global 21-centimetre spectrum5 reveals a stronger absorption than the maximum predicted by existing models, at a confidence level of 3.8 standard deviations. Here we report that this absorption can be explained by the combination of radiation from the first stars and excess cooling of the cosmic gas induced by its interaction with dark matter8,9,10. Our analysis indicates that the spatial fluctuations of the 21-centimetre signal at cosmic dawn could be an order of magnitude larger than previously expected and that the dark-matter particle is no heavier than several proton masses, well below the commonly predicted mass of weakly interacting massive particles. Our analysis also confirms that dark matter is highly non-relativistic and at least moderately cold, and primordial velocities predicted by models of warm dark matter are potentially detectable. These results indicate that 21-centimetre cosmology can be used as a dark-matter probe."

Thanks for that, Danik.

THE SOCIETY FOR POPULAR ASTRONOMY

Electronic News Bulletin No. 464 2018 March 4

http://earthsky.org/earth/wildfires-forecast-US-west

My cousin in California, George Weisz, will know about this, I look forward to a brief correspondence on this.

THE SOCIETY FOR POPULAR ASTRONOMY

Electronic News Bulletin No. 464 2018 March 4

SUN'S MAGNETIC CAGE STOPPED SOLAR ERUPTION
NASA/Goddard Space Flight Center

New research using NASA data shows that a dramatic magnetic power struggle
at the Sun's surface lies at the heart of solar eruptions. The work high-
lights the role of the Sun's magnetic landscape, or topology, in the dev-
elopment of solar eruptions that can trigger 'space weather' events around
the Earth. The scientists examined solar flares, which are intense bursts
of radiation and light. Many strong solar flares are followed by a coronal
mass ejection, or CME, a massive, bubble-shaped eruption of solar material
and magnetic field, but some are not -- what differentiates the two
situations is not clearly understood. Using data from NASA's Solar Dynamics
Observatory, or SDO, the scientists examined a 2014 October Jupiter-sized
sunspot group, an area of complex magnetic fields, often the site of solar
activity. That was the biggest group in the past two solar cycles and a
highly active region. Though conditions seemed ripe for an eruption, the
region never produced a major CME on its journey across the Sun. It did,
however, emit a powerful X-class flare, the most intense class of flares.
What determines, the scientists wondered, whether a flare is associated
with a CME?

The team of scientists included SDO's observations of magnetic fields at the
Sun's surface in powerful models that calculated the magnetic field of the
Sun's corona, or upper atmosphere, and examined how it evolved in the time
just before the flare. The model reveals a battle between two key magnetic
structures: a twisted magnetic rope -- known to be associated with the onset
of CMEs -- and a dense cage of magnetic fields overlying the rope. The
scientists found that that magnetic cage physically prevented a CME from
erupting that day. Just hours before the flare, the sunspot's natural
rotation contorted the magnetic rope and it grew increasingly twisted and
unstable, like a tightly coiled rubber band, but the rope never erupted from
the surface: the model demonstrated that it did not have enough energy to
break through the cage. It was, however, volatile enough to lash through
part of the cage, triggering the strong solar flare. By changing the
conditions of the cage in their model, the scientists found that if the
cage had been weaker that day, a major CME would have erupted. The group is
interested in developing its model further to study how the conflict between
the magnetic cage and rope plays out in other eruptions.

Don´t mention it!

This might also interest peers who live in that area. Here we go:

Wildfires will likely get worse in western North America
A new study projects increases in burning across the U.S. West and Canada. It suggests large fires – such those we’ve seen recently in California – may become more common.
http://earthsky.org/earth/wildfires-forecast-US-west

Very curious!

[QUOTE=Dreamwoven;1349237]THE SOCIETY FOR POPULAR ASTRONOMY

Electronic News Bulletin No. 464 2018 March 4

SUN'S MAGNETIC CAGE STOPPED SOLAR ERUPTION
NASA/Goddard Space Flight Center

New research using NASA data shows that a dramatic magnetic power struggle
at the Sun's surface lies at the heart of solar eruptions. The work high-
lights the role of the Sun's magnetic landscape, or topology, in the dev-
elopment of solar eruptions that can trigger 'space weather' events around
the Earth.

THE SOCIETY FOR POPULAR ASTRONOMY

Electronic News Bulletin No. 464 2018 March 4

NOCTURNAL ANIMALS NAVIGATE BY THE STARS
Lund University:

Nocturnal animals can use the stars and the Milky Way to find their way
during the darkest hours. There are advantages to being active in the
night. Fewer parasites are active, and the same goes for predators.
Moreover, there are not as many competitors for food as there are during
the day. For animals that migrate or search for food over vast distances in
particular, the cooler hours of the night are preferable to the heat of the
day. A key requirement for nocturnal animals is that they can hold their
course in the dark. Migrating birds that take off at sunset rely on their
magnetic compass, but also the star compass when they use individual stars
for orientation. Dung beetles do not use individual stars. Instead they
travel through the night with the help of the light from the Milky Way,
which contrasts with the surrounding dark sky. Studies also support that
seals, moths, frogs and other animals use the starry sky to navigate at
night. Animals with camera eyes, the type of eyes that we humans possess,
can discern individual stars. Insects with compound eyes most likely can
not, but scientists believe that they can interpret the starry sky and the
Milky Way as patterns of light. We still know very little about how
nocturnal animals experience and interpret the night sky. For example, no
one has yet determined whether, and how, migrating birds change their point
of reference in the night sky when they pass the equator. Emerging
technologies, such as highly-sensitive cameras, may allow us to discover
many more species that also use the starry skies to guide them during the
darkest hours of the night.

Interesting post. Even cats seem to feel safer at night, which in human environments can be a mistake. I´m linking this post to the thread "about animals".

Good, thanks Danik. Astonishing that animals can navigate by the stars in the night sky!

It certainly is. Here is another article on another recent theme you posted;

Fingerprinting the very first stars

Using a radio antenna the size of a tabletop, astronomers found evidence suggesting the first stars formed just 180 million years after the Big Bang.
"Like detectives, astronomers can't always just examine a simple image when they want to solve a mystery. Most of the time, the have to meticulously piece together tiny bits of evidence, often by scouring the heavens to hunt for clues. And one of the biggest cosmic cold cases that astronomers have been attempting to solve for years is: When exactly did the first stars form?

This week in the journal Nature, after over a decade of intense experimental investigation, a team of astronomers announced that they have finally cracked the case of the first stars. Using a simple radio antenna the size of a tabletop located in the Australian desert, the researchers discovered the faint fingerprints of the earliest stars in the infant universe, which formed when the cosmos was just 180 million years old."
http://www.astronomy.com/news/2018/0...ry-first-stars

What I like about this article is that its wording is very simple.

Not quite sure where to post this. I refuse to put it in the animal thread. Anyway, meet "Cyberslug":

Virtual predator is 'self-aware', behaves like living counterpart

"Scientists report in the journal eNeuro that they've built an artificially intelligent ocean predator that behaves a lot like the original flesh-and-blood organism on which it was modeled. The virtual creature, "Cyberslug," reacts to food and responds to members of its own kind much like the actual animal, the sea slug Pleurobranchaea californica, does."
https://www.sciencedaily.com/release...0301103130.htm

http://earthsky.org/earth/scientists...danger-islands

A large colony of Adelie penguins has been discovered in the Danger Islands, Antarctica.

http://earthsky.org/earth/scientists...danger-islands

"Scientists recently discovered a “supercolony” of more than 1,500,000 Adélie penguins on the Danger Islands, a chain of remote, rocky islands off the Antarctic Peninsula’s northern tip.

For the past 40 years, the total number of Adélie penguins, one of the most common species of penguins live on the Antarctic peninsula, has been steadily declining — or so biologists thought."

Quote:

---

Originally Posted by Dreamwoven

http://earthsky.org/earth/scientists...danger-islands

"Scientists recently discovered a “supercolony” of more than 1,500,000 Adélie penguins on the Danger Islands, a chain of remote, rocky islands off the Antarctic Peninsula’s northern tip.

For the past 40 years, the total number of Adélie penguins, one of the most common species of penguins live on the Antarctic peninsula, has been steadily declining — or so biologists thought."

---

That´s funny. I was sure that I had answered this post because I linked it to "About animals."
What I don´t like about this kind of discoveries is that with it comes human interference into the animal environment.

Making a splash in search for interstellar water
Date:
March 9, 2018
Source:
NASA/Goddard Space Flight Center
Summary:
Water is crucial for life, but how do you make water? Cooking up some H2O takes more than mixing hydrogen and oxygen. It requires the special conditions found deep within frigid molecular clouds, where dust shields against destructive ultraviolet light and aids chemical reactions. NASA's James Webb Space Telescope will peer into these cosmic reservoirs to gain new insights into the origin and evolution of water and other key building blocks for habitable planets.

https://www.sciencedaily.com/release...0309125213.htm

No, that was post #1670. :)

Stars can exhibit cute behavior too. At least in the eyes of their describers:

Red giant brings its companion star back to life

"There’s some adage out there about helping out your neighbor, right? Well, a red giant star was recently spotted lending more than just a cup of flour to its companion neutron star — it blasted it with winds that nourished the dead star back to life in a burst of X-ray light."
http://www.astronomy.com/news/2018/0...r-back-to-life

http://earthsky.org/space/measuring-...eveals-mystery

By Donna Weaver and Ray Villard/Johns Hopkins

Here’s the good news: Astronomers have made the most precise measurement to date of the rate at which the universe is expanding since the Big Bang.

Here’s the possibly unsettling news: The new numbers remain at odds with independent measurements of the early universe’s expansion, which could mean that there is something unknown about the makeup of the universe.

Is something unpredicted going on in the depths of space?

Adam Riess is a Nobel Laureate and Bloomberg Distinguished Professor at Johns Hopkins University. He said:

The community is really grappling with understanding the meaning of this discrepancy.

Riess leads a team of researchers using the Hubble Space Telescope to measure the expansion rate of the universe. He shared a Nobel Prize in 2011 for the discovery of the accelerating universe.

The team, which includes researchers from Hopkins and the Space Telescope Science Institute, has used the Hubble Space Telescope over the past six years to refine the measurements of the distances to galaxies, using stars as milepost markers. Those measurements are used to calculate how fast the universe expands with time, a value known as the Hubble constant.
By Donna Weaver and Ray Villard/Johns Hopkins