AAS NOVA — Research Highlights 2016

bystander · Post by **bystander** » Mon Jul 25, 2016 5:03 pm

Forming Planets in the Hostile Carina Nebula
NOVA | American Astronomical Society | 2016 July 08

Can protoplanetary disks form and be maintained around low-mass stars in the harsh environment of a highly active, star-forming nebula? A recent study examines the Carina nebula to answer this question. ...

Protoplanetary Disks in the Hostile Environment of Carina - A. Mesa-Delgado et al

Astrophysical Journal Letters 825(1):L16 (01 July 2016) DOI: 10.3847/2041-8205/825/1/L16
arXiv.org > astro-ph > arXiv:1605.08809 > 27 May 2016

bystander · Post by **bystander** » Mon Jul 25, 2016 5:08 pm

A History of Collisions between the Magellanic Clouds
Nova | American Astronomical Society | 2016 July 11

Recent deep observations of the Large Magellanic Cloud (LMC), a satellite galaxy of the Milky Way, have revealed a faint arc of stars extending from its northern outskirts. Was this stream created by the gravitational pull of the Milky Way? Or could it have a more violent source? ...

Low Surface Brightness Imaging of the Magellanic System: Imprints of
Tidal Interactions between the Clouds in the Stellar Periphery - Gurtina Besla et al

Astrophysical Journal 825(1):20 (01 July 2016) DOI: 10.3847/0004-637X/825/1/20
arXiv.org > astro-ph > arXiv:1602.04222 > 12 Feb 2016

http://asterisk.apod.com/viewtopic.php?t=36192

bystander · Post by **bystander** » Mon Jul 25, 2016 5:15 pm

A Preferred Home for Disrupted Stars
Nova | American Astronomical Society | 2016 July 13

Observed “burps” from the shredding of stars by supermassive black holes suggest that this behavior is more common in an unusual type of galaxy. A new study has examined NGC 3156, an example from this galaxy type, to better understand what causes this preference. ...

An Enhanced Rate of Tidal Disruptions in the Centrally Overdense E+A Galaxy NGC 3156 - Nicholas C. Stone, Sjoert van Velzen

Astrophysical Journal Letters 825(1):L14 (01 July 2016) DOI: 10.3847/2041-8205/825/1/L14
arXiv.org > astro-ph > arXiv:1604.02056 > 07 Apr 2016

bystander · Post by **bystander** » Mon Jul 25, 2016 5:27 pm

New Objects Beyond the Kuiper Belt
Nova | American Astronomical Society | 2016 July 15

What has the search for the hypothetical Planet Nine led to? In the case of this study, the discovery of a collection of new — and puzzling — objects located in the outer reaches of our solar system. ...

Beyond the Kuiper Belt Edge: New High Perihelion Trans-Neptunian Objects
with Moderate Semi-Major Axes and Eccentricities - Scott S. Sheppard, Chadwick Trujillo, David J. Tholen

Astrophysical Journal Letters 825(1):L13 (01 July 2016) DOI: 10.3847/2041-8205/825/1/L13
arXiv.org > astro-ph > arXiv:1606.02294 > 07 Jun 2016 (v1), 22 Jun 2016 (v3)

http://asterisk.apod.com/viewtopic.php?t=35962#p260165

bystander · Post by **bystander** » Mon Jul 25, 2016 5:42 pm

Supernova Remnants in the LMC
Nova | American Astronomical Society | 2016 July 18

[c][attachment=0]SNR_LMC.jpg[/attachment][/c][hr][/hr]
These vibrant images (click for the full view!) of supernova remnants in the Large Magellanic Cloud (LMC) were created by mapping data from the Chandra X-ray Telescope into three colors: red for 300–720 eV, green for 720–1100 eV, and blue for 1100–7000 eV. Three scientists at University of Texas at Arlington — Andrew Schenck, Sangwook Park, and Seth Post — created these maps in order to probe the composition of the LMC’s interstellar medium. The forward shocks of supernova remnants sweep up the interstellar medium as they expand, heating it and causing it to emit the X-rays that Chandra observes. Schenck, Park and Post used Chandra’s observations of these remnants to make new measurements of the interstellar metallicities in the LMC. To find out more, check out the paper below!

A Chandra Study of the Interstellar Metallicity in the Large Magellanic Cloud
Using Supernova Remnants - Andrew Schenck, Sangwook Park, Seth Post

Astronomical Journal 151(6):161 (2016 June) DOI: 10.3847/0004-6256/151/6/161
arXiv.org > astro-ph > arXiv:1603.07163 > 23 Mar 2016 (v1), 07 Apr 2016 (v2)

bystander · Post by **bystander** » Mon Jul 25, 2016 5:52 pm

Do Galactic Bars Buckle to Form Bulges?
Nova | American Astronomical Society | 2016 July 20

The Milky Way is one of many galaxies that has a peanut-shaped bulge at its center. A new study has now caught two galaxies in the process of forming similar bulges, yielding insight into how ours was created. ...

Caught in the Act: Direct Detection of Galactic Bars in the Buckling Phase - Peter Erwin, Victor P. Debattista

Astrophysical Journal Letters 825(2):L30 (10 July 2016) DOI: 10.3847/2041-8205/825/2/L30
arXiv.org > astro-ph > arXiv:1607.01290 > 05 Jul 2016

bystander · Post by **bystander** » Mon Jul 25, 2016 6:02 pm

The Hunt for a Counterpart to GW150914
Nova | American Astronomical Society | 2016 July 22

On 14 September 2015, the Laser Interferometer Gravitational-wave Observatory (LIGO) — in a pre-operative testing state at the time — detected its first sign of gravitational-waves. The LIGO team sprang into action, performing data-quality checks on this unexpected signal. Within two days, they had sent a notification to 63 observing teams at observatories representing the entire electromagnetic spectrum, from radio to gamma-ray wavelengths.

Thus began the very first hunt for an electromagnetic counterpart to a detected gravitational wave signal. ...

Localization and Broadband Follow-up of the Gravitational-Wave Transient GW150914 - B. P. Abbott et al

Astrophysical Journal Letters 826(1):L13 (20 July 2016) DOI: 10.3847/2041-8205/826/1/L13
arXiv.org > astro-ph > arXiv:1602.08492 > 26 Feb 2016 (v1), 21 Jul 2016 (v4)

http://asterisk.apod.com/viewtopic.php?t=35646

Ann · Post by **Ann** » Mon Jul 25, 2016 7:48 pm

bystander wrote:Do Galactic Bars Buckle to Form Bulges?
Nova | American Astronomical Society | 2016 July 20

The Milky Way is one of many galaxies that has a peanut-shaped bulge at its center. A new study has now caught two galaxies in the process of forming similar bulges, yielding insight into how ours was created. ...

Caught in the Act: Direct Detection of Galactic Bars in the Buckling Phase - Peter Erwin, Victor P. Debattista
Astrophysical Journal Letters 825(2):L30 (10 July 2016) DOI: 10.3847/2041-8205/825/2/L30
arXiv.org > astro-ph > arXiv:1607.01290 > 05 Jul 2016

: Click to view full size image

NGC 3226 and NGC 3227.
Photo: Kent Biggs.

I can't resist posting this picture of NGC 3227 (and elliptical NGC 3226), since NGC 3227 is one of the galaxies mentioned that has been found to have a buckling bar. (Whatever that means - I can't say I really understood it!)

Ann

bystander · Post by **bystander** » Wed Aug 10, 2016 5:21 pm

A Pulsar and a Disk
Nova | American Astronomical Society | 2016 July 25

Recent, unusual X-ray observations from our galactic neighbor, the Small Magellanic Cloud, have led to an interesting model for SXP 214, a pulsar in a binary star system. ...

SXP214, an X-ray Pulsar in the Small Magellanic Cloud,
Crossing the Circumstellar Disk of the Companion - JaeSub Hong et al

Astrophysical Journal 826(1):4 (2016 July 20) DOI: 10.3847/0004-637X/826/1/4
arXiv.org > astro-ph > arXiv:1605.03672 > 12 May 2016

bystander · Post by **bystander** » Wed Aug 10, 2016 5:36 pm

Observing the Sun with NuSTAR
Nova | American Astronomical Society | 2016 July 29

The Nuclear Spectroscopic Telescope Array (NuSTAR) is a space telescope primarily designed to detect high-energy X-rays from faint, distant astrophysical sources. Recently, however, it’s occasionally been pointing much closer to home, with the goal of solving a few longstanding mysteries about the Sun. ...

The First Focused Hard X-ray Images of the Sun with NuSTAR - Brian W. Grefenstette et al

Astrophysical Journal 826(1):20 (2016 July 20) DOI: 10.3847/0004-637X/826/1/20
arXiv.org > astro-ph > arXiv:1605.09738 > 31 May 2016

bystander · Post by **bystander** » Wed Aug 10, 2016 7:13 pm

Satellite Galaxies of the Milky Way
Nova | American Astronomical Society | 2016 Aug 01

This beautiful 13’ x 13’ image (click for the full view!) holds more than meets the eye. Look closely at the small concentration of blue stars just to the left of center. This is Eridanus II, one of nine new ultra-faint galaxies discovered just last year around the Milky Way. Detected as part of the Dark Energy Survey (DES) and presented in a study led by Sergey E. Koposov (Institute of Astronomy, Cambridge), these new galaxies add to a growing list of very dim satellites that orbit within the Milky Way’s potential. Since their discovery, these DES satellites have been used to answer a number of astronomical questions. In particular, the large dark-matter fraction of these ultra-faint galaxies makes them excellent laboratories for testing models of dark matter in the universe. Check back with us on Wednesday to learn more about what Eridanus II has revealed about dark matter! And for more information on the nine DES-discovered ultra-faint satellites, check out the paper below.

Beasts of the Southern Wild: Discovery of Nine Ultra Faint
Satellites in the Vicinity of the Magellanic Clouds - Sergey E. Koposov et al

Astrophysical Journal 805(2):130 (2015 June 01) DOI: 10.1088/0004-637X/805/2/130
arXiv.org > astro-ph > arXiv:1503.02079 > 06 Mar 2015 (v1), 01 Apr 2015 (v3)

http://asterisk.apod.com/viewtopic.php?t=34531

bystander · Post by **bystander** » Thu Aug 11, 2016 1:40 am

How a Star Cluster Ruled Out MACHOs
Nova | American Astronomical Society | 2016 Aug 03

Are massive black holes hiding in the halos of galaxies, making up the majority of the universe’s mysterious dark matter? This possibility may have been ruled out by a star cluster in a small galaxy recently discovered orbiting the Milky Way. ...

Constraints on MACHO Dark Matter from Compact Stellar Systems in Ultra-Faint Dwarf Galaxies - Timothy D. Brandt

Astrophysical Journal Letters 824(2):L31 (2016 June 20) DOI: 10.3847/2041-8205/824/2/L31
arXiv.org > astro-ph > arXiv:1605.03665 > 12 May 2016 (v1), 09 Jun 2016 (v2)

bystander · Post by **bystander** » Thu Aug 11, 2016 2:07 am

Images of an Activated Asteroid
Nova | American Astronomical Society | 2016 Aug 05

In late April of this year, asteroid P/2016 G1 (PANSTARRS) was discovered streaking through space, a tail of dust extending behind it. What caused this asteroid’s dust activity? ...

Early Evolution of Disrupted Asteroid P/2016 G1 (PANSTARRS) - Fernando Moreno et al

Astrophysical Journal Letters 826(2):L22 (2016 Aug 01) DOI: 10.3847/2041-8205/826/2/L22
arXiv.org > astro-ph > arXiv:1607.03375 > 12 Jul 2016

bystander · Post by **bystander** » Thu Aug 11, 2016 2:16 am

K2’s First Five-Planet System
Nova | American Astronomical Society | 2016 Aug 08

What’s the latest from the Kepler K2 mission? K2 has found its first planetary system containing more than three planets — an exciting five-planet system located ~380 light-years from Earth! ...

Five Planets Transiting a Ninth Magnitude Star - Andrew Vanderburg et al

Astrophysical Journal Letters 827(1):L10 (2016 Aug 10) DOI: 10.3847/2041-8205/827/1/L10
arXiv.org > astro-ph > arXiv:1606.08441 > 27 Jul 2016

bystander · Post by **bystander** » Thu Aug 11, 2016 2:22 am

Exploring the Birth of Binary Stars
Nova | American Astronomical Society | 2016 Aug 10

More than half of all stars are thought to be in binary or multiple star systems. But how do these systems form? The misaligned spins of some binary protostars might provide a clue. ...

The Turbulent Origin of Outflow and Spin Misalignment in Multiple Star Systems - Stella S. R. Offner et al

Astrophysical Journal Letters 827(1):L11 (2016 Aug 10) DOI: 10.3847/2041-8205/827/1/L11
arXiv.org > astro-ph > arXiv:1606.08445 > 27 Jul 2016

bystander · Post by **bystander** » Sat Aug 13, 2016 4:31 pm

A New Player in the Search for Extraterrestrial Intelligence
Nova | American Astronomical Society | 2016 Aug 12

The modern search for extraterrestrial intelligence, known as SETI, began at radio observatories more than 50 years ago. Now scientists at the Murchison Widefield Array (MWA) in Western Australia have launched a new SETI endeavor — the first to look for signals in the low-radio-frequency regime. ...

An Opportunistic Search for ExtraTerrestrial Intelligence (SETI) with the Murchison Widefield Array - S.J. Tingay et al

Astrophysical Journal Letters 827(2):L22 (2016 Aug 20) DOI: 10.3847/2041-8205/827/2/L22
arXiv.org > astro-ph > arXiv:1607.08818 > 29 Jul 2016

bystander · Post by **bystander** » Tue Aug 23, 2016 4:20 pm

Models of a Circumbinary Disk
Nova | American Astronomical Society | 2016 Aug 15

Last week, we discussed a model for how binary star systems might form. The image above (click for the full view!) captures a scene from another study of the formation of multiple-star systems: a series of 2D hydrodynamics simulations of a self-gravitating binary system surrounded by a circumbinary disk. These simulations were performed by Andrew Nelson (Los Alamos National Laboratory) and Francesco Marzari (University of Padua, Italy), who were attempting to better understand observations of GG Tau A, one of two binaries in the quadruple star system GG Tau. Nelson and Marzari use their simulations to demonstrate how spiral structures could form within the circumbinary disk, and how material from the circumbinary disk can substantially feed the individual accretion disks around each star, if the stars are in a wide orbit. To find out more about what they learned (and to see more awesome simulation images!), check out the paper below.

Dynamics of Circumstellar Disks III: The Case of GG Tau A - Andrew F. Nelson, F. Marzari

Astrophysical Journal 827(2):93 (20 Aug 2016) DOI: 10.3847/0004-637X/827/2/93
arXiv.org > astro-ph > arXiv:1605.02764 > 09 May 2016

bystander · Post by **bystander** » Tue Aug 23, 2016 4:29 pm

History of a Rare Radio Galaxy Revealed by Its Jets
Nova | American Astronomical Society | 2016 Aug 17

Most radio galaxies exhibit a single pair of radio lobes marking the endpoints of their jets. But the unusual three pairs of radio lobes of a recently observed radio galaxy may reveal information about this galaxy’s past. ...

J1216+0709: A radio galaxy with three episodes of AGN jet activity - Veeresh Singh et al

Astrophysical Journal 826(2):132 (01 Aug 2016) DOI: 10.3847/0004-637X/826/2/132
arXiv.org > astro-ph > arXiv:1605.05821 > 19 May 2016

bystander · Post by **bystander** » Tue Aug 23, 2016 4:49 pm

A High-Velocity Collision With Our Galaxy’s Disk
Nova | American Astronomical Society | 2016 Aug 19

What caused the newly discovered “supershell” in the outskirts of our galaxy? A new study finds evidence that a high-velocity cloud may have smashed into the Milky Way’s disk millions of years ago. ...

A High-Velocity Cloud Impact Forming a Supershell in the Milky Way - Geumsook Park et al

Astrophysical Journal Letters 827(2):L27 (20 Aug 2016) DOI: 10.3847/2041-8205/827/2/L27
arXiv.org > astro-ph > arXiv:1607.07699 > 26 Jul 2016

bystander · Post by **bystander** » Tue Aug 23, 2016 4:54 pm

When Charged Black Holes Merge
Nova | American Astronomical Society | 2016 Aug 22

Most theoretical models assume that black holes aren’t charged. But a new study shows that mergers of charged black holes could explain a variety of astrophysical phenomena, from fast radio bursts to gamma-ray bursts. ...

Mergers of Charged Black Holes: Gravitational Wave Events, Short Gamma-Ray Bursts, and Fast Radio Bursts - Bing Zhang

Astrophysical Journal Letters 827(2):L31 (20 Aug 2016) DOI: 10.3847/2041-8205/827/2/L31
arXiv.org > astro-ph > arXiv:1602.04542 > 15 Feb 2016 (v1), 13 Jul 2016 (v4)

bystander · Post by **bystander** » Tue Sep 20, 2016 3:03 pm

The (Historical) Search for Planets Orbiting Proxima Centauri
Nova | American Astronomical Society | 2016 Aug 24

We’ve spent the last couple decades searching for planets around our nearest stellar neighbor, the red dwarf Proxima Centauri. Here’s a look at what we’ve learned so far.

A Possible Companion to Proxima Centauri - A. B. Schultz et al

Astronomical Journal 115(1):345 (1998 Jan) DOI: 10.1086/300176

Wide Field Planetary Camera 2 Observations of Proxima Centauri:
No Evidence of the Possible Substellar Companion - David A. Golimowski, Daniel J. Schroeder

Astronomical Journal 116(1):440 (1998 July) DOI: 10.1086/300437

Interferometric Astrometry of Proxima Centauri and Barnard's Star Using Hubble Space
Telescope Fine Guidance Sensor 3: Detection Limits for Substellar Companions - G. Fritz Benedict et al

Astronomical Journal 118(2):1086 (1999 Aug) DOI: 10.1086/300975
arXiv.org > astro-ph > arXiv:astro-ph/9905318 > 25 May 1999

The HARPS-TERRA Project. I. Description of the Algorithms, Performance,
and New Measurements on a Few Remarkable Stars Observed by HARPS - Guillem Anglada-Escudé, R. Paul Butler

Astrophysical Journal Supplement 200(2):15 (2012 June) DOI: 10.1088/0067-0049/200/2/15
arXiv.org > astro-ph > arXiv:1202.2570 > 12 Feb 2012 (v1), 19 Apr 2012 (v2)

The Solar Neighborhood. XXXIV. A Search for Planets Orbiting Nearby M Dwarfs using Astrometry - John C. Lurie et al

Astronomical Journal 148(5):91 (2014 Nov) DOI: 10.1088/0004-6256/148/5/91
arXiv.org > astro-ph > arXiv:1407.4820 > 17 Jul 2014

http://asterisk.apod.com/viewtopic.php?t=36287

bystander · Post by **bystander** » Tue Sep 20, 2016 3:14 pm

New Efforts to Identify Dark Matter
Nova | American Astronomical Society | 2016 Aug 26

Could the dark matter in our universe be “warm” instead of “cold”? Recent observations have placed new constraints on the warm dark matter model.

A Stringent Limit on the Warm Dark Matter Particle Masses from
the Abundance of z = 6 Galaxies in the Hubble Frontier Fields - N. Menci et al

Astrophysical Journal Letters 825(1):L1 (2016 July 01) DOI: 10.3847/2041-8205/825/1/L1
arXiv.org > astro-ph > arXiv:1606.02530 > 08 Jun 2016 (v1), 10 Jun 2016 (v3)

bystander · Post by **bystander** » Tue Sep 20, 2016 3:21 pm

Monitoring Holes in the Sun’s Corona
Nova | American Astronomical Society | 2016 Aug 31

Coronal holes are where the fast solar wind streams out of the Sun’s atmosphere, sending charged particles on rapid trajectories out into the solar system. A new study examines how the distribution of coronal holes has changed over the last 40 years.

Long-Term Trend of Solar Coronal Hole Distribution from 1975 to 2014 - K. Fujiki et al

Astrophysical Journal Letters 827(2):L41 (2016 Aug 20) DOI: 10.3847/2041-8205/827/2/L41

bystander · Post by **bystander** » Tue Sep 20, 2016 3:35 pm

Rings from Close Encounters
Nova | American Astronomical Society | 2016 Sep 02

We’ve recently discovered narrow sets of rings around two minor planets orbiting in our solar system. How did these rings form? A new study shows that they could be a result of close encounters between the minor planets and giants like Jupiter or Neptune.

Formation of Centaurs’ Rings through Their Partial Tidal Disruption during Planetary Encounters - Ryuki Hyodo et al

Astrophysical Journal Letters 828(1):L8 (2016 Sep 01) DOI: 10.3847/2041-8205/828/1/L8
arXiv.org > astro-ph > arXiv:1608.03509 > 11 Aug 2016 (v1), 01 Sep 2016 (v2)

bystander · Post by **bystander** » Tue Sep 20, 2016 3:43 pm

Building Up the Milky Way’s Skeleton
Nova | American Astronomical Society | 2016 Sep 09

A team of scientists has now uncovered half of the entire “skeleton” of the Milky Way, using an automated method to identify large filaments of gas and dust hiding between stars in the galactic plane.

A Census of Large-Scale (≥10 PC), Velocity-Coherent, Dense Filaments in the Northern
Galactic Plane: Automated Identification Using Minimum Spanning Tree - Ke Wang et al

Astrophysical Journal Supplement 226(1):9 (2016 Sep) DOI: 10.3847/0067-0049/226/1/9
arXiv.org > astro-ph > arXiv:1607.06452 > 21 Jul 2016

Starship Asterisk*

AAS NOVA — Research Highlights 2016

Nova: Forming Planets in the Hostile Carina Nebula

Nova: A History of Collisions between the Magellanic Clouds

Nova: A Preferred Home for Disrupted Stars

Nova: New Objects Beyond the Kuiper Belt

Nova: Supernova Remnants in the LMC

Nova: Do Galactic Bars Buckle to Form Bulges?

Nova: The Hunt for a Counterpart to GW150914

Re: Nova: Do Galactic Bars Buckle to Form Bulges?

Nova: A Pulsar and a Disk

Nova: Observing the Sun with NuSTAR

Nova: Satellite Galaxies of the Milky Way

Nova: How a Star Cluster Ruled Out MACHOs

Nova: Images of an Activated Asteroid

Nova: K2’s First Five-Planet System

Nova: Exploring the Birth of Binary Stars

Nova: A New Player in the Search for Extraterrestrial Intelligence

Nova: Models of a Circumbinary Disk

Nova: History of a Rare Radio Galaxy Revealed by Its Jets

Nova: A High-Velocity Collision With Our Galaxy’s Disk

Nova: When Charged Black Holes Merge

Nova: The (Historical) Search for Planets Orbiting Proxima Centauri

Nova: New Efforts to Identify Dark Matter

Nova: Monitoring Holes in the Sun’s Corona

Nova: Rings from Close Encounters

Nova: Building Up the Milky Way’s Skeleton