The stable retrograde orbit of the Bee-Zed asteroid explained
https://phys.org/news/2017-06-stable-retrograde-orbit-bee-zed-asteroid.html

In our solar system, an asteroid orbits the sun in the opposite direction to the planets. Asteroid 2015 BZ509, also known as Bee-Zed, takes 12 years to
make one complete orbit around the sun. This is the same orbital period as that of Jupiter, which shares its orbit but moves in the opposite direction.

RThe asteroid with the retrograde co-orbit was identified by Helena Morais, a professor at São Paulo State University's Institute of Geosciences & Exact
Sciences (IGCE-UNESP). Morais had predicted the discovery two years earlier, and has published his findings in Nature.

"It's good to have confirmation," Morais said. "I was sure retrograde co-orbits existed. We've known about this asteroid since 2015, but the orbit hadn't
been clearly determined, and it wasn't possible to confirm the co-orbital configuration. Now it's been confirmed after more observations that reduced the
number of errors in the orbital parameters. So, we're sure the asteroid is retrograde, co-orbital and stable."

In partnership with Fathi Namouni at the Côte d'Azur Observatory in France, Morais developed a general theory on retrograde co-orbitals and retrograde
orbital resonance.

VIRGO: chápu :)

Galaxy NGC 1132 has a disturbed hot halo, study finds
https://phys.org/news/2017-06-galaxy-ngc-disturbed-hot-halo.html

A new study recently published on arXiv.org reveals that the fossil group galaxy NGC 1132 (also known as UGC 2359) has a disturbed and asymmetrical hot halo.
The findings provide new insights into the formation and evolution of this galaxy and could improve our understanding of fossil groups in the universe.

Located some 318 million light years away from the Earth, NGC 1132 is a well-known fossil galaxy group. The so-called "fossil group" is an isolated elliptical
galaxy embedded in an extended halo of X-ray emitting gas the size of a galaxy group. Such groups are believed to be the end result of galaxy merging within
a normal galaxy group, leaving behind the X-ray halo of the progenitor group.

NEBULA: Já teď nestíhám nic kromě práce, která se po té pauze nakupila. Hrůza...

VIRGO: půjdeš se tam podívat?

Discoveries Fuel Fight Over Universe’s First Light | Quanta Magazine
https://www.quantamagazine.org/discoveries-fuel-fight-over-universes-first-light-20170519/

A series of observations at the very edge of the universe has reignited a debate over what lifted the primordial cosmic fog.

Not long after the Big Bang, all went dark. The hydrogen gas that pervaded the early universe would have snuffed out the light of the universe’s
first stars and galaxies. For hundreds of millions of years, even a galaxy’s worth of stars — or unthinkably bright beacons such as those created
by supermassive black holes — would have been rendered all but invisible.

Eventually this fog burned off as high-energy ultraviolet light broke the atoms apart in a process called reionization. But the questions of exactly
how this happened — which celestial objects powered the process and how many of them were needed — have consumed astronomers for decades.

Now, in a series of studies, researchers have looked further into the early universe than ever before. They’ve used galaxies and dark matter as a giant
cosmic lens to see some of the earliest galaxies known, illuminating how these galaxies could have dissipated the cosmic fog. In addition, an international
team of astronomers has found dozens of supermassive black holes — each with the mass of millions of suns — lighting up the early universe. Another team
has found evidence that supermassive black holes existed hundreds of millions of years before anyone thought possible. The new discoveries should make
clear just how much black holes contributed to the reionization of the universe, even as they’ve opened up questions as to how such supermassive
black holes were able to form so early in the universe’s history.

The Shapes of Galaxiessu201723 | www.cfa.harvard.edu/
https://www.cfa.harvard.edu/news/su201723

Since Edwin Hubble proposed his galaxy classification scheme in 1926, numerous studies have investigated the physical mechanisms responsible
for the shapes of spiral and elliptical galaxies. Because the processes are complex, however, studies frequently rely on computer simulations
as their main tool. The discs of galaxies are believed to form through the collapse of gas which acquires its initial spin in the early Universe.
During their subsequent evolution, galaxies undergo a wide range of phenomena, from the accretion of matter -- or its outflow -- to mergers with
other galaxies, all of which modify the disk’s spin and angular momentum.

Astronomers think that spiral galaxies with the largest galactic discs formed preferentially in protogalaxies with the highest angular momentum,
although early attempts to verify this prediction using computer simulations failed. (More recently, simulations have been able to verify this
trend.) Elliptical galaxies, on the other hand, are believed to be the remnants of repeated galaxy mergers, but their shapes depend on many details
like the galaxies' masses, gas content, and the collision parameters. As a result, these mergers need to be considered over a cumulative,
cosmological context with large numbers of examples to evaluate their development from a statistical perspective.

CfA astronomers Vicente Rodriguez-Gomez, Annalisa Pillepich and Lars Hernquist led a team that analyzed the morphologies of about eighteen thousand
galaxies in the Illustris computer simulation. Both disc and spheroidal galaxies arise naturally in this simulation. They find that massive merging
galaxies develop into spirals or spheroidal shapes depending on their gas content (as expected, since the star formation activity depends crucially
on the gas). Unexpectedly, they find that for lower mass galaxies -- roughly the mass of the Milky Way or smaller -- mergers do not seem to play
a significant role in determining the morphology. The reason appears to be that in higher mass mergers a galaxy accretes many more stars from
the partner, and this plays the a critical role. Their significant conclusion is that only in massive galaxies are mergers the dominant factor
in shaping the system.

VIRGO:

Tisícovka vědců představí na týdnu astronomie v Praze svůj výzkum | ČeskéNoviny.cz
http://www.ceskenoviny.cz/...sicovka-vedcu-predstavi-na-tydnu-astronomie-v-praze-svuj-vyzkum/1500846

https://www.nature.com/nature/journal/v546/n7659/full/nature22388.html