Very bright fireball spotted over Abilene, Texas on April 19, 2017
Fireball event
http://www.amsmeteors.org/members/imo_view/event/2017/1418

AMS event #1418-2017
https://www.youtube.com/watch?v=wP_wHKfGIVA



Same bright fireball spotted over Amarillo, Texas on April 19, 2017
http://www.amsmeteors.org/members/imo_view/event/2017/1418

AMS event #1418-2017
https://www.youtube.com/watch?v=b6GIZPjjrsI

A matter of distance | ESA/Hubble
https://www.spacetelescope.org/images/potw1717a/

In space, being outshone is an occupational hazard. This NASA/ESA Hubble Space Telescope image captures a galaxy named NGC 7250.
Despite being remarkable in its own right — it has bright bursts of star formation and recorded supernova explosions— it blends
into the background somewhat thanks to the gloriously bright star hogging the limelight next to it.

This bright object is a single and little-studied star named TYC 3203-450-1, located in the constellation of Lacerta (The Lizard),
much closer than the much more distant galaxy. Only this way a normal star can outshine an entire galaxy, consisting of billions
of stars. Astronomers studying distant objects call these stars “foreground stars” and they are often not very happy about them,
as their bright light is contaminating the faint light from the more distant and interesting objects they actually want to study.

Astronomers detect dozens of new quasars and galaxies
https://phys.org/news/2017-04-astronomers-dozens-quasars-galaxies.html

A team of astronomers led by Yoshiki Matsuoka of the National Astronomical Observatory of Japan (NAOJ) has detected a treasure trove
of new high-redshift quasars (or quasi-stellar objects) and luminous galaxies. The newly found objects could be very important for
our understanding of the early universe. The findings were presented Apr. 19 in a paper published on arXiv.org.

High-redshift quasars and galaxies (at redshift higher than 5.0) are useful probes of the early universe in many respects. They offer
essential clues on the evolution of the intergalactic medium, quasar evolution, early supermassive black hole growth, as well as
evolution of galaxies through cosmic times. Generally speaking, they enable scientists to study the universe when it looked much
different than it does today.

Recently, Matsuoka's team has presented the results from the Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs) project,
which uses multi-band photometry data provided by the Hyper Suprime-Cam (HSC) Subaru Strategic Program (SSP) survey. HSC is a wide-field
camera installed on the Subaru 8.2 m telescope located at the summit of Maunakea, Hawaii and operated by NAOJ. The researchers selected
nearly 50 photometric candidates from the HSC-SSP source catalog and then observed them with spectrographs on the Subaru Telescope and
the Gran Telescopio Canarias (GTC), located on the island on the Canary Island of La Palma, Spain.

The observations resulted in the identification of 24 new quasars and eight new luminous galaxies at redshift between 5.7 and 6.8.

Mars Trojans may be part of a planet that was destroyed long ago | New Scientist
https://www.newscientist.com/...81-mars-trojans-may-be-part-of-a-planet-that-was-destroyed-long-ago/

Mars has an asteroid entourage, with nine so-called Trojans trailing in its wake. Now it seems these travelling
companions all had the same violent beginning: as the innards of a mini-planet, eviscerated in a violent collision.
Some remnants may even have been incorporated into the material that became Mars.

Trojans are distinct from the asteroids found in the asteroid belt, which begins about 101 million kilometres past Mars
and stretches toward Jupiter. While Trojans orbit the sun, like the asteroid belt, they are trapped in gravitational
sweet spots that ensure they will permanently trail or precede the planet in its trip around our star. These are known
as Lagrange points.

Weird, hairy microbes discovered on volcano soon after eruption | New Scientist
https://www.newscientist.com/...8570-weird-hairy-microbes-discovered-on-volcano-soon-after-eruption/

Gone today, hair tomorrow. Soon after an underwater volcano erupted and wiped out all nearby life forms,
hardy bacteria moved in and covered the area in a huge mat of hair-like filaments.

These strange colonies were found by an expedition to Tagoro Volcano, near the Canary Islands, in 2014,
two years after an eruption that reshaped 9 square kilometres of the sea floor. The researchers explored
the area via a robotic submarine equipped with cameras and arms for collecting samples.

Asteroid shock waves could have provided the building blocks for RNA - ScienceAlert
http://www.sciencealert.com/the-building-blocks-for-rna-could-be-the-result-of-asteroid-shock-waves

A now famous experiment conducted by chemists Stanley Miller and Harold Urey back in 1952 showed that even if we don't know for sure how the first living
cells formed, at least some of their molecular building blocks could have been produced by simple chemical reactions under conditions on ancient Earth.

Now, more than half a century later, researchers from France and the Czech Republic have used a similar experiment to expand this list of potential
ingredients to include all four RNA bases, filling in some possible stepping stones on the pathway from chemical soup to the origins of life.

While the results don't show how life probably formed, they do demonstrate that conditions on Earth roughly 3.5 to 4 billion years ago could have been
sufficient to produce the toolbox of compounds necessary for biochemistry.

Those conditions include what was probably an atmosphere without oxygen – referred to as a reducing atmosphere – and warm bodies of water containing
nitrogen and carbon-based molecules such as ammonia and methane.

Miller and Urey dissolved these two compounds in a sterile flask of water with some hydrogen gas for their experiment, letting it sit for a week before
shocking the solution with electricity to simulate lightning strikes.

NASA VR: Cassini's Grand Finale (360 view)
https://www.youtube.com/watch?v=hFjzFSidX3s

Petr Horálek - Lovy skvostů temné oblohy (Pátečníci 10.6.2016)
https://www.youtube.com/watch?v=2Kv-H1spCLU

NASA’s Cassini, Voyager Missions Suggest New Picture of Sun’s Interaction with Galaxy
https://www.nasa.gov/...assini-voyager-missions-suggest-new-picture-of-sun-s-interaction-with-galaxy

New data from NASA’s Cassini mission, combined with measurements from the two Voyager spacecraft and NASA’s Interstellar Boundary Explorer, or IBEX,
suggests that our sun and planets are surrounded by a giant, rounded system of magnetic field from the sun — calling into question the alternate view
of the solar magnetic fields trailing behind the sun in the shape of a long comet tail.

The sun releases a constant outflow of magnetic solar material — called the solar wind — that fills the inner solar system, reaching far past the orbit
of Neptune. This solar wind creates a bubble, some 23 billion miles across, called the heliosphere. Our entire solar system, including the heliosphere,
moves through interstellar space. The prevalent picture of the heliosphere was one of comet-shaped structure, with a rounded head and an extended tail.
But new data covering an entire 11-year solar activity cycle show that may not be the case: the heliosphere may be rounded on both ends, making its
shape almost spherical. A paper on these results was published in Nature Astronomy on April 24, 2017.

Jellyfish-shaped galaxy found in Abell 2670 cluster
https://phys.org/news/2017-04-jellyfish-shaped-galaxy-abell-cluster.html

Using the Multi Unit Spectroscopic Explorer (MUSE), astronomers have identified a new elliptical jellyfish-like galaxy in the Abell 2670 cluster.
The newly detected galaxy showcases spectacular one-sided tails of gas and young stars, which indicates intense ram-pressure stripping.
The findings were presented Apr. 18 in a paper published on the arXiv pre-print server.

Messier 78: HD View of A Reflective Nebula : VLT Telescope / Astronomy Video
https://www.youtube.com/watch?v=cXtyRnUdBFM

A Black Hole in a Low Mass X-Ray Binarysu201715 | www.cfa.harvard.edu/
https://www.cfa.harvard.edu/news/su201715

A globular cluster is a roughly spherical ensemble of stars (as many as several million) that are gravitationally bound together,
and typically located in the outer regions of galaxies. Low mass X-ray binary stars (LMXBs) are systems in which one star is compact
(a neutron star or black hole) and is accreting matter from a companion star. Astronomers have long noticed that there are fractionally
many more LMXBs in globular clusters than elsewhere in the galaxy, an overabundance that is usually attributed to the high stellar
density in globular clusters. But this calls attention to another unusual feature of the LMXBs in globulars. In the galactic field,
most LXMBs are formed from binary stars as they age and evolve, but in globular clusters it has been shown that most LMXBs form when
compact objects encounter and then capture another star. There are many neutron stars in clusters, but black holes that form in these
dense stellar environments are expected either to sink down to the center of the cluster or else to be gravitationally ejected from
the cluster after they are formed. Indeed, all of the LMXBs seen in globular clusters are of the type with a neutron star.

NASA's Fermi Catches Gamma-ray Flashes from Tropical Storms
https://www.nasa.gov/...ture/goddard/2017/nasas-fermi-catches-gamma-ray-flashes-from-tropical-storms

About a thousand times a day, thunderstorms fire off fleeting bursts of some of the highest-energy light naturally found on Earth.
These events, called terrestrial gamma-ray flashes (TGFs), last less than a millisecond and produce gamma rays with tens of millions
of times the energy of visible light. Since its launch in 2008, NASA's Fermi Gamma-ray Space Telescope has recorded more than 4,000 TGFs,
which scientists are studying to better understand how the phenomenon relates to lightning activity, storm strength and the life cycle of
storms.

Now, for the first time, a team of NASA scientists has analyzed dozens of TGFs launched by the largest and strongest weather systems on
the planet: tropical storms, hurricanes and typhoons. A paper describing the research was published March 16 in the Journal of Geophysical
Research: Atmospheres.

NASA's Fermi Catches Gamma-ray Flashes from Tropical Storms
https://www.youtube.com/watch?v=f3lx0yzZXNQ

What Should A Black Hole's Event Horizon Look Like?
https://www.forbes.com/.../ask-ethan-what-should-a-black-holes-event-horizon-look-like/#91c401271075

Simulated galaxies provide fresh evidence of dark matter - Durham University
https://www.dur.ac.uk/news/newsitem/?itemno=31169

Further evidence of the existence of dark matter – the mysterious substance that is believed to hold the Universe together –
has been produced by Cosmologists at Durham University.

Using sophisticated computer modelling techniques, the research team simulated the formation of galaxies in the presence of
dark matter and were able to demonstrate that their size and rotation speed were linked to their brightness in a similar way
to observations made by astronomers.

One of the simulations is pictured, showing the main ingredients that make up a galaxy: the stars (blue), the gas from which
the stars are born (red), and the dark matter halo that surrounds the galaxy (light grey).