Starship Asterisk*

Susanna Kohler wrote:
The merger of two compact objects — neutron stars or black holes — could be accompanied by a sudden, immediate flash of radio emission, according to predictions. Can an array of antennas in California help us spot these signals? ...

• Astrophysical Journal Letters 877(2):L39 (2019 Jun 01) DOI: 10.3847/2041-8213/ab2248
• arXiv.org > astro-ph > arXiv:1903.06786 > 15 Mar 2019

Susanna Kohler wrote:
How do we get the heavy elements — elements with atomic mass above iron, like gold, platinum, or uranium — in our universe? A new study suggests that one theorized source, collapsing massive stars, may not be the best option. ...

• Astrophysical Journal Letters 877(2):L24 (2019 Jun 01) DOI: 10.3847/2041-8213/ab2049
• arXiv.org > astro-ph > arXiv:1905.04315 > 10 May 2019

Susanna Kohler wrote:
The stunning substructures of gaps and rings revealed in protoplanetary disks have been attributed to the motions of hidden, newly formed planets. But are we interpreting our observations correctly? ...

• Astrophysical Journal Letters 878(1):L9 (2019 Jun 10) DOI: 10.3847/2041-8213/ab22a7
• arXiv.org > astro-ph > arXiv:1905.08259 > 20 May 2019

Kerry Hensley wrote:
When massive stars explode as supernovae, they fling shredded stellar material into the interstellar medium. The explosion should also generate gravitational waves, but astronomers haven’t detected any yet. Is it just a matter of time before we detect gravitational waves from core-collapse supernovae, or are the signals still out of reach? ...

• Astrophysical Journal Letters 876(1):L9 (2019 May 01) DOI: 10.3847/2041-8213/ab191a
• arXiv.org > astro-ph > arXiv:1812.07703 > 18 Dec 2018 (v1), 23 Apr 2019 (v3)

Susanna Kohler wrote:
What happens to Venus when an enormous solar eruption slams into the planet? In 2011, the Venus Express spacecraft was on site to find out! ...

• Astrophysical Journal 876(1):84 (2019 May 01) DOI: 10.3847/1538-4357/ab14e1

Susanna Kohler wrote:
When the Laser Interferometer Gravitational-Wave Observatory (LIGO) discovered its first merging black holes, astronomers were surprised: these black holes were much larger than we had expected! A new study looks at what these observations might tell us about black holes in star clusters. ...

• Astrophysical Journal Letters 878(1):L1 (2019 Jun 10) DOI: 10.3847/2041-8213/ab2336
• arXiv.org > astro-ph > arXiv:1901.03345 > 10 Jan 2019 (v1),21 May 2019 (v2)

Susanna Kohler wrote:
Massive stars can die in a lot of different ways! A new study explores one possible channel in more detail. ...

• Astrophysical Journal Letters 876(2):L29 (2019 May 10) DOI: 10.3847/2041-8213/ab1bdf
• arXiv.org > astro-ph > arXiv:1903.02135 > 06 Mar 2019 (v1), 25 Apr 2019 (v2)

Kerry Hensley wrote:
Powerful solar flares are dazzlingly bright in ultraviolet and X-ray images of the Sun. Despite their demands for attention, there’s still a lot that we don’t know about these unpredictable eruptions. ...

• Astrophysical Journal 879(2):128 (2019 July 10) DOI: 10.3847/1538-4357/ab262e
• arXiv.org > astro-ph > arXiv:1905.13356 > 30 May 2019

Susanna Kohler wrote:
For all that space telescopes are powerful tools for exploring our universe, we can achieve some remarkable science using ground-based observations! A new study explores the lessons learned from five years of monitoring Jupiter’s volcanic moon Io from the ground. ...

• Astronomical Journal 158(1):29 (2019 July) DOI: 10.3847/1538-3881/ab2380
• arXiv.org > astro-ph > arXiv:1906.05426 > 12 Jun 2019

Susanna Kohler wrote:
Astronomy is driven forward by a combination of novel observations and complex, inventive modeling. How can astronomers better analyze their models? A new study presents a tool for the job — and is also the first article published under a new partnership between the American Astronomical Society (AAS) and the Journal of Open Source Software. ...

• Astrophysical Journal Supplement 242(2):22 (2019 June) DOI: 10.3847/1538-4365/ab1f7d
• arXiv.org > astro-ph > arXiv:1901.08725 > 25 Jan 2019 (v1), 12 Jun 2019 (v3)

Susanna Kohler wrote:
Can we use clues from the present to figure out how a planet has been blasted by the radiation of its host star in the past? According to a new study, it’s a definite possibility. ...

• Astrophysical Journal 879(1):26 (2019 Jul 01) DOI: 10.3847/1538-4357/ab1e42
• arXiv.org > astro-ph > arXiv:1906.12153 > 28 Jun 2019

Kerry Hensley wrote:
Many people start to slow down as they age, and stars seem to be the same way. Astronomers measure how fast stars spin to determine their ages, but new measurements suggest that some stars may wind down more quickly than others. ...

• Astrophysical Journal 879(1):49 (2019 Jul 01) DOI: 10.3847/1538-4357/ab2393
• arXiv.org > astro-ph > arXiv:1905.06869 > 16 May 2019 (v1), 25 May 2019 (v3)

Susanna Kohler wrote:
There’s still a lot we don’t know about the internal structure and behavior of neutron stars, the compact remnants of giant, collapsed stars. Can the mergers of neutron stars with another type of exotic object, black holes, reveal important information? ...

• Astrophysical Journal 877(2):94 (2019 Jun 01) DOI: 10.3847/1538-4357/ab1b15
• arXiv.org > astro-ph > arXiv:1808.06848 > 21 Aug 2018

Susanna Kohler wrote:
Though Kepler’s primary mission ended years ago, the resulting dataset remains a vast playground in which astronomers continue to discover new surprises in stellar light curves. The latest? Evidence of a white dwarf that defies all expectations. ...

• Astrophysical Journal Letters 881(1):L3 (2019 Aug 10) DOI: 10.3847/2041-8213/ab321b
• arXiv.org > astro-ph > arXiv:1907.07656 > 17 Jul 2019 (v1), 11 Aug 2019 (v2)

Susanna Kohler wrote:
Let’s be honest: the universe has an awful lot of gas. But the gas discovered in a new study isn’t your run-of-the-mill atomic gas! We’ve now found dense, star-formation-enabling molecular gas farther out than ever before. ...

• Astrophysical Journal Letters 880(2):L19 (2019 Aug 01) DOI: 10.3847/2041-8213/ab2ed9
• arXiv.org > astro-ph > arXiv:1907.02721 > 05 Jul 2019

Susanna Kohler wrote:
Pisces–Eridanus may try to pass itself off as a billion years old, but scientists are calling its bluff. The Transiting Exoplanet Survey Satellite (TESS) has now carded this nearby stream of stars, revealing that it’s actually a relative baby! ...

• Astronomical Journal 158(2):77 (2019 Aug) DOI: 10.3847/1538-3881/ab2899
• arXiv.org > astro-ph > arXiv:1905.10588 > 25 May 2019

Kerry Hensley wrote:
With energies a thousand times greater than an average solar flare, stellar superflares can strip away atmospheres and endanger life on planetary surfaces. These violent outbursts often go hand in hand with coronal mass ejections, shaping the evolution of planets near and far. ...

• Astrophysical Journal 880(2):97 (2019 Aug 01) DOI: 10.3847/1538-4357/ab287e
• arXiv.org > astro-ph > arXiv:1906.03189 > 07 Jun 2019 (v1), 30 Jul 2019 (v2)

Kerry Hensley wrote:
Saturn may appear calm and motionless from afar, but the immense planet is subtly pulsing and oscillating — and those oscillations impose a pattern on the planet’s rings that could tell us about Saturn’s history. ...

• Astrophysical Journal 881(2):142 (2019 Aug 20) DOI: 10.3847/1538-4357/ab2892
• arXiv.org > astro-ph > arXiv:1901.04511 > 14 Jan 2019

Susanna Kohler wrote:
Though dark matter appears to be common in the universe, there’s still a lot we don’t know about it. A new study has now shed some light on this mysterious topic using faint satellite galaxies around the Milky Way. ...

• Astrophysical Journal Letters 878(2):L32 (2019 Jun 20) DOI: 10.3847/2041-8213/ab1eb2
• arXiv.org > astro-ph > arXiv:1904.10000 > 22 Apr 2019 (v1), 19 Jun 2019 (v2)

Susanna Kohler wrote:
Remember KIC 8462852, better known as Boyajian’s star (or you may have seen it referred to as the “alien megastructure” star)? We still don’t have a definitive explanation for this source’s odd behavior — in part because we thought that Boyajian’s star was one-of-a-kind.

But what if it isn’t?

• Astrophysical Journal Letters 880(1):L7 (2019 Jul 20) DOI: 10.3847/2041-8213/ab2e77

Susanna Kohler wrote:
Short-duration gamma-ray bursts (GRBs) are brief flashes of high-energy emission lasting less than two seconds. These events have long been hypothesized to occur when two neutron stars spiral in and collide, launching enormously powerful jets of light and matter. Can we now definitively make this connection? ...

• Astrophysical Journal Letters 880(2):L23 (2019 Aug 01) DOI: 10.3847/2041-8213/ab2fd4
• arXiv.org > astro-ph > arXiv:1905.02665 > 07 May 2019

Susanna Kohler wrote:
How can we measure the masses of free-floating planets wandering around our galaxy? A new study identifies one approach that combines the power of two upcoming missions. ...

• Astrophysical Journal Letters 880(2):L32 (2019 Aug 01) DOI: 10.3847/2041-8213/ab2da5
• arXiv.org > astro-ph > arXiv:1908.02720 > 07 Aug 2019

Susanna Kohler wrote:
When a passing star gets a little too close to a massive black hole, destruction ensues. But how does the star’s age affect the outcome? ...

• Astrophysical Journal Letters 882(2):L25 (2019 Sep 10) DOI: 10.3847/2041-8213/ab379a
• arXiv.org > astro-ph > arXiv:1907.04859 > 10 Jul 2019 (v1), 06 Aug 2019 (v2)

Susanna Kohler wrote:
Sometimes slow and steady wins the race — like in the long-term, continuous monitoring of a variable star. A collection of more than 100 years of data has now given us a rare opportunity to watch, in real time, as a star evolves. ...

• Astrophysical Journal 879(1):62 (2019 Jul 01) DOI: 10.3847/1538-4357/ab22a5
• arXiv.org > astro-ph > arXiv:1905.00597 > 02 May 2019 (v1), 04 Jun 2019 (v2)

Susanna Kohler wrote:
The Earth is constantly being bombarded by cosmic rays — high energy protons and atomic nuclei that speed through space at nearly the speed of light. Where do these energetic particles come from? A new study examines whether pulsars are the source of one particular cosmic-ray conundrum. ...

• Astrophysical Journal 878(2):104 (2019 Jun 20) DOI: 10.3847/1538-4357/ab20c9
• arXiv.org > astro-ph > arXiv:1810.10928 > 25 Oct 2018 (v1), 09 May 2019 (v3)