astrobites 2017

Find out the latest thinking about our universe.
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Re: Can we see neutrinos from ... ?

Postby BDanielMayfield » Fri Apr 14, 2017 6:50 pm

Since neutrinos are nearly impossible to detect how can the origin (the direction they come from) of the very few that are detected be determined?

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Re: Can we see neutrinos from ... ?

Postby Chris Peterson » Fri Apr 14, 2017 7:08 pm

BDanielMayfield wrote:Since neutrinos are nearly impossible to detect how can origin (the direction they come from) of the very few that are detected be determined?

When neutrinos are associated with a transient or intermittent source, the signal rises above the background rate. If you have two or more widely separated detectors, you can correlate those peaks (looking at arrival time) and determine a direction. In the case of steady sources which add to the background, you can statistically correlate all arrival times at one station with those from another and identify source directions.
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Re: Can we see neutrinos from ... ?

Postby BDanielMayfield » Fri Apr 14, 2017 7:45 pm

Chris Peterson wrote:
BDanielMayfield wrote:Since neutrinos are nearly impossible to detect how can [the] origin (the direction they come from) of the very few that are detected be determined?

When neutrinos are associated with a transient or intermittent source, the signal rises above the background rate.

Yes, as when a spike in detection corresponds with a SN blast.
If you have two or more widely separated detectors, you can correlate those peaks (looking at arrival time) and determine a direction. In the case of steady sources which add to the background, you can statistically correlate all arrival times at one station with those from another and identify source directions.

I see. Thanks.

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The birth of a new field

Postby bystander » Tue Apr 18, 2017 4:02 pm

The birth of a new field
astrobites | 2017 Apr 14
Kelly Malone wrote:
Today’s paper is historical in nature rather than a current summary – it describes the 1989 paper that essentially birthed the field of ground-based gamma-ray astrophysics by making the first > 5 sigma detection of a TeV gamma-ray source! ...

Observation of TeV gamma rays from the Crab Nebula using the Atmospheric Cerenkov Imaging technique - T. C. Weekes et al
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Reionization of Dwarfs in the Local Group

Postby bystander » Tue Apr 18, 2017 4:09 pm

Reionization of Dwarfs in the Local Group
astrobites | 2017 Apr 17
Stacy Kim wrote:
There was a time in the universe when there were no stars. It was only after a long, dark 100 million years or so that the first stars—giant, blindingly bright monoliths a species apart from today’s stars—blinked on. As these stars blazed to life, they unleashed vast amounts of energetic ultraviolet (UV) photons. The universe at that time was filled mostly with cold hydrogen gas—cold enough to be in neutral form, single atoms of hydrogen. The UV photons unleashed by the stars changed this—they heated up the hydrogen gas and broke the atoms up into bare protons and electrons. This process was so efficient that the entire universe was reionized. ...

Reionization of the Milky Way, M31, and Their Satellites
I: Reionization History and Star Formation
- Keri L. Dixon et al
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Live fast, die young: quiescent galaxies in the early universe

Postby bystander » Tue Apr 18, 2017 4:20 pm

Live fast, die young: quiescent galaxies in the early universe
astrobites | 2017 Apr 18
Christopher Lovell wrote:
Galaxies in the early universe tend to be young and carefree. They have plenty of gas, and set about vigorously forming lots of stars. As a galaxy gets older though, it starts to run out of gas and becomes quiescent, no longer forming stars (see these bites for more details on quiescent galaxies). Theorists predict that it takes at least a few gigayears to deplete the gas, and this can be sped up by mergers and interactions with other galaxies. So, the further away we look (which corresponds to looking further back in time) the fewer quiescent galaxies we expect to see.

Today’s paper is about the snappily named ZF-COSMOS-20115, a quiescent galaxy at the unusually high redshift of 3.7, around one and a half billion years after the big bang. It has a mass equivalent to 170 billion suns, making it one of the most massive galaxies at this point in the universe’s history (much bigger than other similarly quiescent galaxies at this time), but it’s also very compact, less than a kiloparsec across (in comparison, our own Milky Way is ~ 50 kiloparsecs across). How did ZF-COSMOS-20115 become quiescent so quickly after forming, and is it a challenge to our current understanding of galaxy evolution? ...

A massive, quiescent galaxy at a redshift of 3.717 - Karl Glazebrook et al

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Active Cryovolcanism on Europa?

Postby bystander » Sat Apr 22, 2017 7:59 pm

Active Cryovolcanism on Europa?
astrobites | 2017 Apr 20
Joseph Schmitt wrote:
Europa, one of Jupiter’s Galilean moons, is one of the most exciting places in the search for alien life in our solar system, rivaling both Mars and Saturn’s moon Enceladus. Underneath a 15-25 km surface layer of ice, Europa very likely has a thick (~100 km) ocean of salty water with a rocky seafloor. Chemical reactions on the icy surface caused by high-energy particles from Jupiter’s radiation belts could provide some of the essential ingredients for life, but only if this material could somehow reach the liquid water beneath it. These geological properties make Europa a prime candidate for potential alien life. ...

The authors of the article in today’s Astrobite did follow-up Hubble observations in early 2016. They also observed a potential plume of water vapor in the same location as the previous observations, although they were still unable to definitively confirm it. There are two popularly supported mechanisms for creating these plumes: an explosion of dissolved gases in a pressurized liquid after the outside pressure has been removed and the expansion of ice when a trapped body of water freezes that then breaks out of its enclosure. ...

Active Cryovolcanism on Europa? - William B. Sparks et al
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Cradles of Massive Stars

Postby bystander » Sat Apr 22, 2017 8:16 pm

Cradles of Massive Stars
astrobites | 2017 Apr 20
Benny Tsang wrote:
Today let’s talk about massive stars! My favorite view of massive stars is the Hubble image of the star cluster R136 in the Large Magellanic Cloud. All the blue shining spots in this picture are massive stars, with masses up to hundreds of solar masses that are million times brighter than the sun! Massive stars bring beauty to our night skies, as well as structures to our Universe. The Hubble image shows massive stars in their magnificent adulthood. But have you ever wondered what they looked like when they were still babies? ...

Thermal Feedback in the High-mass Star and Cluster Forming Region W51 - Adam Ginsburg et al
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2 slow, 2 furious

Postby bystander » Sat Apr 22, 2017 8:39 pm

2 slow, 2 furious
astrobites | 2017 Apr 21
Paddy Alton wrote:
Scientific papers are a bit like buses. Sometimes you wait for ages waiting for one to take you where you want to go, then – surprise, surprise – two come along at once. This is, of course, a fundamental physical law, to which even astrophysicists are not immune.

In today’s article I’m going to break with tradition a little bit and highlight not one, but two papers, released weeks apart and with similar goals. This happens reasonably often, principally because if the science is both exciting and possible, chances are more than one team are looking into it! It’s always interesting to see independent groups take on the same question – and of course, the replicability of results is at the core of the scientific method. So for those reasons, and in the interests of fairness, let’s look at two takes on the origin of fast and slow rotating elliptical galaxies. ...

The MASSIVE Survey - VII. The Relationship of Angular Momentum,
Stellar Mass, and Environment of Early-Type Galaxies
- Melanie Veale et al
The SAMI Galaxy Survey: Mass as the Driver of the Kinematic
Morphology - Density Relation in Clusters
- Sarah Brough et al
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Breaking Planet Chains and Cracking the Kepler Dichotomy

Postby bystander » Fri Apr 28, 2017 3:57 pm

Breaking Planet Chains and Cracking the Kepler Dichotomy
astrobites | 2017 Apr 24
Michael Hammer wrote:
To migrate, or not to migrate? That is the question. Of course, since planets are not Shakespearean characters, they should not have a choice! When a planet forms in a disk, it creates two spiral waves: a weaker one ahead of the planet that drags it forward (sending the planet outwards), and a stronger one behind the planet that pulls it backwards (sending the planet inwards). Ultimately, every planet should migrate inwards and in most cases, end up much closer to its star than where it formed.

When planets in the outer disk migrate inwards faster than planets closer in, they start to catch up to each other. As these planets get closer together, they eventually become gravitationally locked into resonance: pairs of orbits where the outer planet takes exactly twice as long (or another integer ratio such as 3-to-2, etc.) to complete an orbit around its star as the inner one. Once this happens, the planets migrate together, maintaining that 2-to-1 ratio. In systems with many rocky planets, the third one will follow suit and fall into a resonance with the second planet, as will the fourth with the third, and so on. Eventually, the system will have a long chain of up to 10 resonant rocky planets tightly packed in the inner part of the disk!

Yet even though migration is supposed to be inevitable, only about 5% of the planetary systems discovered by the Kepler mission are actually in this setup (TRAPPIST-1 is the most famous). The other 95% are not, many of which because they only have one planet. Today’s paper, led by Andre Izidoro, attempts to explain these discrepancies by suggesting that all systems migrate into resonant chains, but not all of them stay in resonant chains! ...

Breaking the Chains: Hot Super-Earth systems from migration and disruption of compact resonant chains - Andre Izidoro et al
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Spinning Up Massive Classical Bulges in Spiral Galaxies

Postby bystander » Fri Apr 28, 2017 4:05 pm

Spinning Up Massive Classical Bulges in Spiral Galaxies
astrobites | 2017 Apr 25
Sandeep Kumar Kataria wrote:
The mass of spiral galaxies is mainly distributed in three components: the classical bulge (ClB), disc, and surrounding dark matter halo. Classical bulges are the central building blocks of many early-type spiral galaxies (see the Astrobites Guide to Galaxy Types). These bulges might have formed as a result of collisions between galaxies in the early universe or various other processes mentioned in this paper. It is believed that initially the motion of stars in ClBs is disordered, so the ClB does not rotate. The authors of this paper see an interesting problem to ponder: in the present day, there is an observed net rotation of stars in classical bulges. The origin of this rotation is still to be understood in detail.

One of the authors of this paper has explained in earlier work that low-mass classical bulges spin up by absorbing angular momentum from galactic bars. The bar has a pattern speed, which is a measure of the collective rotation of a family of orbits of stars in the bar. Angular momentum exchange from the bar mainly occurs at resonances in the disc. These are locations where the difference between disc’s rotation speed and the bar pattern speed have specific ratios with radial oscillations of the stars in the disc. These resonances can be thought of as analogous to resonances in an organ pipe, the natural frequency of which corresponds to waves with wavelengths which match the length of the organ pipe. Let’s see how the authors approach the solution of the rotation problem in ClBs. ...

Spin-up of massive classical bulges during secular evolution - Kanak Saha, Ortwin Gerhard, Inma Martinez-Valpuesta
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The Backwards Discs around Be/X-ray Binaries

Postby bystander » Fri Apr 28, 2017 4:13 pm

The Backwards Discs around Be/X-ray Binaries
astrobites | 2017 Apr 26
Matthew Green wrote: ...
In the standard X-ray binary model, material is pulled from the atmosphere of the donor star by the accretor’s gravity. Today’s paper is about Be/X-ray binaries, a special case in which the donor star is a Be-type star and the transferred material is a stellar wind. A Be star is a star spinning so fast that it throws some of its own matter off into space. Put a Be star into orbit around a neutron star, and some of that expelled matter will fall towards the neutron star — and voilà, you have your accretion. The orbits of these systems are often elliptical, meaning that at some points in their orbit the stars are close together (resulting in a higher accretion rate and an extra spurt of X-ray emission) and at others they are further apart (causing a dip in the X-ray emission). ...

Retrograde Accretion Disks in High-Mass Be/X-ray Binaries - D. M. Christodoulou, S. G. T. Laycock, D. Kazanas
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16th Century Statisticians and Alien Oceans

Postby bystander » Fri Apr 28, 2017 4:20 pm

16th Century Statisticians and Alien Oceans
astrobites | 2017 Apr 27
Elisabeth Matthews wrote:
We exist.

That might seem like an obvious statement, but it’s one of the observations that drives today’s paper.

It’s a provocative piece of work by Fergus Simpson, which attempts to understand – robustly and with Bayesian statistics – what we can infer about potential aliens based on the data point that is us. Given that we exist, and our planet is like this, can we infer anything about other planets that host intelligent life? This Bayes primer might be useful if you’re not familiar with the concept.

Simpson is responsible for the Big Alien Theory, where he predicts that aliens typically live on planets smaller than Earth and weigh around 300kg. For more on that, see the paper and his website explaining the idea.

This is a follow-up to that paper, with a focus on the water coverage of planets that host intelligent life. ...

Bayesian Evidence for the Prevalence of Waterworlds - Fergus Simpson

viewtopic.php?t=37098
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The stellar evolution conspiracy, part I

Postby bystander » Wed May 03, 2017 5:43 pm

The stellar evolution conspiracy, part I
astrobites | 2017 Apr 30
Leonardo dos Santos wrote:
Practically all areas of research in astrophysics depend on how well we understand the life and death of stars. Habitability of exoplanets? Yes. Evolution of galaxies? Definitely. The nature of dark matter? Yup. The search for extraterrestrial life? You bet. This is such a crucial component of astrophysics that I decided to discuss the issue in more than one bite (the next one is coming soon). Stars are ubiquitous and drive countless phenomena in the universe. And that is why, at the end of every day, I always ask myself: how much should we trust our understanding of stellar evolution? ...

Confronting uncertainties in stellar physics II. Exploring differences in main-sequence stellar evolution tracks - R. J. Stancliffe et al
Confronting uncertainties in stellar physics: Calibrating convective overshooting with eclipsing binaries - R. J. Stancliffe et al
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A reversible N-body integrator with JANUS

Postby bystander » Wed May 03, 2017 5:50 pm

A reversible N-body integrator with JANUS
astrobites | 2017 May 01
Suk Sien Tie wrote:
It is simply astronomical, everything in astronomy: there are too many objects, everything happens on mega glacial time scale over mega glacial distance, space is too big, and objects are almost always certainly too faint. With our finite resources and human lifetimes, it is impossible to observe everything and to follow their evolution religiously from the beginning to the end. However, (super)computers have endowed astronomers with divine powers, allowing us to manipulate the Universe at our fingertips. In the absence of data, they are also the next favorite playgrounds to put theories to the test. Simulations have become the bread and butter of astronomical research.

The underlying schemes used in simulations can be divided into those that deal with collisional fluid (hydrodynamics simulations) and those that deal with pure gravitational dynamics (N-body simulation), although there are growing instances of hybrid simulations. The Millennium Simulation is an example of an N-body simulation. In today’s bite, we focus on N-body simulation and discuss a numerical method (aka an integrator) that solves a problem facing all dynamical integrators, which is that of time-reversibility. ...

JANUS: A bit-wise reversible integrator for N-body dynamics - Hanno Rein, Daniel Tamayo
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Counterparts to Gravitational Wave Events

Postby bystander » Wed May 03, 2017 5:59 pm

Counterparts to Gravitational Wave Events:
Very Important Needles in a Very Large Haystack

astrobites | 2017 May 02
Thankful Cromartie wrote:
The LIGO Scientific Collaboration’s historic direct detection of gravitational waves (GWs) brought with it the promise of answers to long-standing astrophysical puzzles that were unsolvable with traditional electromagnetic (EM) observations. In previous astrobites, we’ve mentioned that an observational approach that involves both the EM and GW windows into the Universe can help shed light on mysteries such as the neutron star (NS) equation of state, and can serve as a unique test of general relativity. Today’s paper highlights the biggest hinderance to EM follow-up of GW events: the detection process doesn’t localize the black hole (BH) and NS mergers well enough to inform a targeted observing campaign with radio, optical, and higher-frequency observatories. While EM counterparts to GW-producing mergers are a needle that’s likely worth searching an entire haystack for, the reality is that telescope time is precious, and everyone needs a chance to use these instruments for widely varying scientific endeavors. ...

Where and When: Optimal scheduling of the electromagnetic follow-up
of gravitational-wave events based on counterpart lightcurve models
- Om Sharan Salafia et al
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Lakes, an atmosphere and bubbles? Titan has it all

Postby bystander » Wed May 03, 2017 6:07 pm

Lakes, an atmosphere and bubbles? Titan has it all
astrobites | 2017 May 03
Amber Hornsby wrote:
Orbiting the awe inspiring ring-planet Saturn, the Cassini spacecraft continues to uncover the secrets of its host and its neighbouring moons. Saturn’s sixth moon, Titan, is the second largest moon in our Solar System and is probably one of the most diverse ones. Due to its unique atmosphere – it’s the only moon to have one – its surface is also home to the only extra-terrestrial source of stable liquid that we know of. Recently, scientists have observed peculiar features present on the surfaces of these vast lakes of methane. It is these oddities and the simulations designed to explain them which are the subject of today’s astrobite. ...

Bubble streams in Titan’s seas as a product of liquid N2 + CH4 + C2H6 cryogenic mixture - Daniel Cordier et al
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Run away, star

Postby bystander » Sat May 06, 2017 3:09 pm

Run away, star
astrobites | 2017 May 04
Philipp Plewa wrote:
The fastest known stars in the Galaxy are the ones orbiting the supermassive black hole in its very center. At the time of closest approach to the black hole, these stars can reach speeds on the order of 10000 km/s or more. Their origin is suspected to be the Hills mechanism: If a binary star system is scattered into the vicinity of the black hole, by gravitational interaction one of the companion stars can get captured on a close orbit, while the other is ejected.

A few extremely fast-moving stars have also been discovered in the Galactic halo, traveling at speeds exceeding 500 km/s, some of which could even escape the Milky Way. Presumably, these hypervelocity stars are the Hills stars now outbound from the Galactic center, although alternative explanations have been proposed as well. The authors of today’s paper explore yet another scenario: Could the Milky Way’s hypervelocity stars originate from the Large Magellanic Cloud (LMC)? ...

Hypervelocity Runaways from the Large Magellanic Cloud - Douglas Boubert et al

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A new fitness diagnosis of hot Jupiters

Postby bystander » Sat May 06, 2017 3:16 pm

A new fitness diagnosis of hot Jupiters
astrobites | 2017 May 05
Shang-Min Tsai wrote:
In the field of exoplanets, hot Jupiters are the first friends we discovered two decades ago. We now know they are usually loners. They are most likely not formed in situ but migrated from the outer disk. They are expected to be synchronized to their parent stars by close-in tidal interactions. Nevertheless, there are still a few open questions that we do not understand yet. The inflated radius is one of them (see this previous bites). In today’s paper, the authors provide a new approach to tackle the conundrum. ...

Advection of potential temperature in the atmosphere of irradiated
exoplanets: A robust mechanism to explain radius inflation
- P. Tremblin et al
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New information from an old result: planets in globular clusters

Postby bystander » Thu May 11, 2017 5:08 pm

New information from an old result: planets in globular clusters
astrobites | 2017 May 08
Eckhart Spalding wrote:
If the orbital plane of an exoplanetary system is almost edge-on as seen from Earth, there is a good chance the system’s close-in planets will ‘transit’, or pass directly over the face of the host star. When this happens, we see the total light from the system make a characteristic dip. ...

A general-purpose space telescope like HST is good at making sensitive optical observations, but the restricted fields-of-view and the high competition for observing time make them unsuitable for large-scale surveys. But Gilliland et al. had an idea: why not harness the sensitivity of HST to observe a dense globular cluster, where thousands of stars are packed together in the field of view?

The proposal was accepted. In July 1999, Gilliland et al. burned through 120 HST orbits to stare at the 120-light-year-distant cluster 47 Tucanae for 8.3 days. They monitored a field of 34,000 stars in a pioneering observation which today remains the deepest exoplanet transit survey of any globular cluster. Know what they found, aside from some variable stars?

Nothing. ...

Or was it? In today’s paper, Masuda et al. look back at Gilliland et al.’s result and ask, ‘Based on our much better understanding of planet statistics seventeen years on, do we still come to the same conclusions?’ ...

Reassessment of the Null Result of the HST Search for Planets in 47 Tucanae - Kento Masuda, Joshua N. Winn
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Setting (photon) sail for Alpha Centauri

Postby bystander » Thu May 11, 2017 5:16 pm

Setting (photon) sail for Alpha Centauri
astrobites | 2017 May 09
Kerrin Hensley wrote:
In August 2016, astronomers announced the discovery of a potentially Earth-like planet in orbit around Proxima Centauri, the Sun’s nearest stellar companion. With this announcement, we humans—the eager, sometimes greedy explorers that we are—are already itching to scout out this far-off planet. Where we can’t go we send robotic surrogates, their instruments more sensitive to photons than human eyes, more sensitive to particles than human hands. These stand-ins stare unblinking at the glare of the Sun. They celebrate lonely birthdays coated in the red dust of Mars. And given enough time, they leave the Solar System behind. Time is precious to us, though, and the distance traveled by Voyagers 1 and 2 in their 39-year lifespan is just 0.05% of the distance to Proxima Centauri; traveling at the same rate as Voyager 1, it would take over 75,000 years to reach the Sun’s nearest companion. Humans are far too impatient to wait that long. How can we get there faster? ...

In this paper, the authors expand upon the photon sail idea in a way that minimizes the travel time to the α Centauri system while maximizing the potential to do meaningful science once there. They integrate the stellar radiation pressure along the photon sail’s path and use a modified N-body code to show that the combined gravitational pull and radiation pressure of the stars in the α Centauri system can be used to steer a photon sail through the system — possibly even into a stable orbit around Proxima Centauri. ...

Deceleration of High-velocity Interstellar Photon Sails into Bound Orbits at α Centauri - René Heller et al
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The Origin of the IceCube Neutrinos: An Ongoing Mystery

Postby bystander » Thu May 11, 2017 5:27 pm

The Origin of the IceCube Neutrinos: An Ongoing Mystery
astrobites | 2017 May 10
Nora Shipp wrote:
The IceCube Neutrino Observatory is a giant telescope embedded deep within the South Pole ice – a trap waiting to detect elusive astrophysical neutrinos. These neutrinos have traveled from violent, often explosive astrophysical sources all the way to the Earth without interacting with another particle. Many of these neutrinos will pass straight through the Earth and out the other side without leaving a trace. However, the strings of detectors inserted a kilometer deep into the Antarctic ice that make up IceCube (Fig. 1) can detect the radiation produced by rare neutrino interactions and, in fact, the IceCube collaboration announced the first ever detection of astrophysical neutrinos back in 2013. (Check out this astrobite on their discovery!) The origin of these particles, however, remains a mystery. ...

Evidence against Star-forming Galaxies as the Dominant Source of Icecube Neutrinos - Keith Bechtol et al
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Icy quake-y comet!

Postby bystander » Sun May 14, 2017 1:50 pm

Icy quake-y comet!
astrobites | 2017 May 11
Bhawna Motwani wrote:
Amongst all kinds of small bodies in our solar system, comets are undoubtedly the most beautiful, and the most elusive. Hiding the clues to our beginnings in their mesmerizing tails, they silently streak across the dark sky. No doubt that these tiny balls of ice are of great interest to people entrenched in the quest to learn how the solar system came to be. ...

Today’s paper presents how rapidly the material making up a comet swiftly evolves from its pristine subsurface form to a dark, dehydrated state, showing that a pristine interior could be hidden under an evolved and altered surface of comets such as 67P for billions of years. In addition to shedding light on the processes that shape comets, the results of today’s paper would significantly aid future assessment of the composition as well as morphology of other small bodies, and their ties to the composition and dynamics within the early Solar system.

The pristine interior of comet 67P revealed by the combined Aswan outburst and cliff collapse - M. Pajola et al
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bystander
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Distilling Astronomy

Postby bystander » Sun May 14, 2017 2:15 pm

Distilling Astronomy
astrobites | 2017 May 12
Emily Sandford wrote:
Let’s start with a short, back-of-the-envelope (back-of-the-blog-post?) calculation.

  1. Roughly 50 new astronomy papers appear on the arXiv every day.
  2. A typical paper is 10 pages long, with (conservatively) 500 words per page.
  3. The average human reads 250 words per minute.
So if you wanted to keep up, in detail, with every new development in astronomy, you’d have to spend about 17 hours per day reading. Perfect! Just enough time for a restful 7 hours of sleep before hitting the arXiv anew. (Astrobites will save you a little time, but even we can only summarize about one paper per day!) ...

Clearly, a lot of astronomy is being done. But is so much astronomy good for astronomy? ...

Research Debt - Chris Olah, Shan Carter
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk.
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Re: Distilling Astronomy

Postby Chris Peterson » Sun May 14, 2017 2:24 pm

bystander wrote:Distilling Astronomy
astrobites | 2017 May 12
Emily Sandford wrote:
Let’s start with a short, back-of-the-envelope (back-of-the-blog-post?) calculation.

  1. Roughly 50 new astronomy papers appear on the arXiv every day.
  2. A typical paper is 10 pages long, with (conservatively) 500 words per page.
  3. The average human reads 250 words per minute.
So if you wanted to keep up, in detail, with every new development in astronomy, you’d have to spend about 17 hours per day reading. Perfect! Just enough time for a restful 7 hours of sleep before hitting the arXiv anew. (Astrobites will save you a little time, but even we can only summarize about one paper per day!) ...

Clearly, a lot of astronomy is being done. But is so much astronomy good for astronomy? ...

Research Debt - Chris Olah, Shan Carter

The argument is flawed. You don't keep up with astronomy (or any scientific field) by reading papers. You keep up with your personal area of specialization by reading papers. If you're interested in other areas of science, you keep up by reading summaries of research. Only occasionally would you actually go to a source paper for something outside your own area of expertise.
Chris

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