AAS NOVA — Research Highlights 2018

Find out the latest thinking about our universe.
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A New Look at the Solar Corona

Post by bystander » Sat Sep 22, 2018 3:54 pm

A New Look at the Solar Corona
NOVA | American Astronomical Society | 2018 Sep 21
Kerry Hensley wrote:
The hot, tenuous solar corona is visible during a total solar eclipse, and astronomers have long studied the structure and dynamics of the ghostly coronal streamers. Now, a special observing campaign has allowed us to see the corona in unprecedented detail. ...

The Highly Structured Outer Solar Corona ~ C. E. DeForest et al
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Planning for Images of a Black Hole

Post by bystander » Thu Sep 27, 2018 3:57 pm

Planning for Images of a Black Hole
NOVA | American Astronomical Society | 2018 Sep 24
Susanna Kohler wrote:
In 2006 an ambitious project was begun: creating the world’s largest telescope with the goal of imaging the shadow of a black hole. But how will we analyze the images this project produces? ...

The Event Horizon Telescope (EHT) ...

Principal Component Analysis as a Tool for Characterizing Black Hole Images and Variability ~ Lia Medeiros et al
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JunoCam Captures Dynamics of Jupiter’s Great Red Spot

Post by bystander » Thu Sep 27, 2018 4:03 pm

JunoCam Captures Dynamics of Jupiter’s Great Red Spot
NOVA | American Astronomical Society | 2018 Sep 26
Susanna Kohler wrote:
A camera on the Juno spacecraft has returned stunning high-resolution images of Jupiter’s Great Red Spot. What can we learn about the properties of this long-lived storm? ...

The Rich Dynamics of Jupiter’s Great Red Spot from JunoCam: Juno Images ~ A. Sánchez-Lavega et al
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Unexpected Discovery of a Bright Cow

Post by bystander » Fri Sep 28, 2018 3:48 pm

Unexpected Discovery of a Bright Cow
NOVA | American Astronomical Society | 2018 Sep 28
Susanna Kohler wrote:
The recent discovery of an unusual transient event, nicknamed “the Cow”, has set the community of transient astronomers abuzz (amoo?). What do we know about this odd event so far? ...

The Cow: Discovery of a Luminous, Hot, and Rapidly Evolving Transient ~ S.J. Prentice et al
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Investigating Our Expanding Universe

Post by bystander » Wed Oct 03, 2018 3:58 pm

Investigating Our Expanding Universe
NOVA | American Astronomical Society | 2018 Oct 03
Susanna Kohler wrote:
The universe is expanding — but we’re still not sure how quickly! With past measurements of this expansion rate causing yielding conflict and debate, a new study investigates whether we can resolve the evident tension. ...

The Trouble with Hubble: Local versus Global Expansion Rates in Inhomogeneous
Cosmological Simulations with Numerical Relativity
~ Hayley J. Macpherson et al
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Oscillations in the Eye of the Bull

Post by bystander » Sat Oct 06, 2018 1:49 pm

Oscillations in the Eye of the Bull
NOVA | American Astronomical Society | 2018 Oct 05
Kerry Hensley wrote:
Aldebaran, the brightest star in the constellation Taurus, was one of the first stars suspected to harbor an exoplanet. The presence of its planetary companion, Aldebaran b, was confirmed in 2015, and the decades of data preceding the discovery might harbor a few more surprises. ...

Aldebaran b's Temperate Past Uncovered in Planet Search Data ~ Will M. Farr et al
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Re: Investigating Our Expanding Universe

Post by Ann » Sat Oct 06, 2018 4:46 pm

bystander wrote:
Wed Oct 03, 2018 3:58 pm
Investigating Our Expanding Universe
NOVA | American Astronomical Society | 2018 Oct 03
Susanna Kohler wrote:
The universe is expanding — but we’re still not sure how quickly! With past measurements of this expansion rate causing yielding conflict and debate, a new study investigates whether we can resolve the evident tension. ...

The Trouble with Hubble: Local versus Global Expansion Rates in Inhomogeneous
Cosmological Simulations with Numerical Relativity
~ Hayley J. Macpherson et al
Here's a naive amateur's question. Couldn't the two values be reconciled if the Universe is gradually picking up speed? So that, when we look at the low Planck value of H0, Planck is taking the relatively slow expansion of the young Universe into account, whereas the Hubble value mostly reflects the faster expansion of the local Universe?

Ann
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Chris Peterson
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Re: Investigating Our Expanding Universe

Post by Chris Peterson » Sat Oct 06, 2018 5:45 pm

Ann wrote:
Sat Oct 06, 2018 4:46 pm
bystander wrote:
Wed Oct 03, 2018 3:58 pm
Investigating Our Expanding Universe
NOVA | American Astronomical Society | 2018 Oct 03
Susanna Kohler wrote:
The universe is expanding — but we’re still not sure how quickly! With past measurements of this expansion rate causing yielding conflict and debate, a new study investigates whether we can resolve the evident tension. ...

The Trouble with Hubble: Local versus Global Expansion Rates in Inhomogeneous
Cosmological Simulations with Numerical Relativity
~ Hayley J. Macpherson et al
Here's a naive amateur's question. Couldn't the two values be reconciled if the Universe is gradually picking up speed? So that, when we look at the low Planck value of H0, Planck is taking the relatively slow expansion of the young Universe into account, whereas the Hubble value mostly reflects the faster expansion of the local Universe?
It can all be very confusing. H0 is actually the present value of the Hubble parameter H. H does vary with time, but it is decreasing, not increasing.
Chris

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Ann
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Re: Investigating Our Expanding Universe

Post by Ann » Sat Oct 06, 2018 6:01 pm

Chris Peterson wrote:
Sat Oct 06, 2018 5:45 pm

It can all be very confusing. H0 is actually the present value of the Hubble parameter H. H does vary with time, but it is decreasing, not increasing.
Even though the expansion of the Universe is picking up speed?

Ann
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Chris Peterson
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Re: Investigating Our Expanding Universe

Post by Chris Peterson » Sun Oct 07, 2018 1:51 pm

Ann wrote:
Sat Oct 06, 2018 6:01 pm
Chris Peterson wrote:
Sat Oct 06, 2018 5:45 pm

It can all be very confusing. H0 is actually the present value of the Hubble parameter H. H does vary with time, but it is decreasing, not increasing.
Even though the expansion of the Universe is picking up speed?

Ann
Yes. It has to do with how the parameter is defined can calculated. Like I said, confusing.
Chris

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Cloudbait Observatory
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How to Turn Off a Galaxy’s Star Formation

Post by bystander » Wed Oct 10, 2018 4:53 pm

How to Turn Off a Galaxy’s Star Formation
NOVA | American Astronomical Society | 2018 Oct 08
Susanna Kohler wrote:
New observations by the Atacama Large Millimeter/submillimeter Array (ALMA) provide a close look at a galaxy that may be in the process of shutting down its star formation. ...

Astronomers probe 'outstanding mystery' of how galaxies stop building stars
University of Kansas | 2018 Sep 12

Violent Quenching: Molecular Gas Blown to 1000 km/s during a Major Merger ~ J.E. Geach et al
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Two Explosions with Similar Quirks

Post by bystander » Sat Oct 13, 2018 3:41 pm

Two Explosions with Similar Quirks
NOVA | American Astronomical Society | 2018 Oct 12
Susanna Kohler wrote:
High-energy radiation released during the merger of two neutron stars last year has left astronomers puzzled. Could a burst of gamma rays from 2015 help us to piece together a coherent picture of both explosions? ...

Fermi GBM Observations of GRB 150101B: A Second Nearby Event with a Short Hard Spike and a Soft Tail ~ E. Burns et al
Know the quiet place within your heart and touch the rainbow of possibility; be
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