Scientists identify a black hole choking on stardust | MIT News
http://news.mit.edu/2017/black-hole-choking-stardust-0315
Data suggest black holes swallow stellar debris in bursts.

In the center of a distant galaxy, almost 300 million light years from Earth, scientists have discovered a supermassive black hole
that is “choking” on a sudden influx of stellar debris.

In a paper published today in Astrophysical Journal Letters, researchers from MIT, NASA’s Goddard Space Flight Center, and elsewhere
report on a “tidal disruption flare” — a dramatic burst of electromagnetic activity that occurs when a black hole obliterates a nearby
star. The flare was first discovered on Nov. 11, 2014, and scientists have since trained a variety of telescopes on the event to learn
more about how black holes grow and evolve.

The MIT-led team looked through data collected by two different telescopes and identified a curious pattern in the energy emitted by
the flare: As the obliterated star’s dust fell into the black hole, the researchers observed small fluctuations in the optical and UV bands
of the electromagnetic spectrum. This very same pattern repeated itself 32 days later, this time in the X-ray band.

Astrobiologie: Přístroje pro sondy JUICE a ExoMars 2020 - Kalendář akcí | Přírodovědci.cz
https://www.prirodovedci.cz/kalendar-akci/astrobiologie-pristroje-pro-sondy-juice-a-exomars-2020

Prof. Aharon Oren přednese na naší fakultě dvě přednášky — Přírodovědecká fakulta UK
https://www.natur.cuni.cz/...ulta/aktuality/prof-aharon-ohren-prednese-na-nasi-fakulte-dve-prednasky

https://www.nasa.gov/image-feature/jpl/pia17213/farewell-to-mimas
In its season of "lasts," NASA's Cassini spacecraft made its final close approach to Saturn's moon Mimas on January 30, 2017. At closest approach,
Cassini passed 25,620 miles (41,230 kilometers) from Mimas. All future observations of Mimas will be from more than twice this distance.

This mosaic is one of the highest resolution views ever captured of the icy moon. Close approaches to Mimas have been somewhat rare during Cassini's
mission, with only seven flybys at distances of less than 50 000 kilometers.

ALMA nahlíží do srdce hvězdných školek | ESO Česko
http://www.eso.org/public/czechrepublic/images/potw1711a/?lang

Zdá se, že velké spirální galaxie se svými nápadnými svítícími rameny přitahují veškerou pozornost. Ale NGC 6822, nepravidelná trpasličí galaxie s příčkou,
dokazuje, že pravidelné spirální galaxie nemají monopol na galaktickou krásu. NGC 6822, které se také říká Barnardova galaxie, leží v souhvězdí Střelce
(Sagittarius) ve vzdálenosti 1.6 milionu světelných let a je plná oblastí tvorby hvězd.

Tento nový obrázek je kombinací starších pozorování pořízených kamerou WFI (Wide Field Imager) na 2.2m dalekohledu MPG/ESO na observatoři ESO La Silla a nových
dat z interferometru ALMA (Atacama Large Millimeter/submillimeter Array). Oblasti pozorované ALMou jsou na obrázku zvýrazněny a dají se prohlédnout v detailu.

Pozorování z dalekohledu ALMA odhalují s neuvěřitelným rozlišením strukturu oblaků obsahujících plyn, ze kterého se tvoří hvězdy. Z pozorování v naší vlastní
galaxii víme, že hvězdy se tvoří v hustých jádrech velkých oblaků molekulárního vodíku - v jediných místech, kde se plyn stane dostatečně chladným na to, aby
vlastní gravitací zkolaboval. Tyto podmínky podporují také tvorbu dalších molekul, např. oxidu uhelnatého, které jsou nenahraditelnou pomůckou astronomů při
detekování galaktického molekulárního vodíku.

Až donedávna byli astronomové schopní rozlišist oblasti tvorby hvězd pouze v Mléčné dráze, ale vysoké rozlišení ALMy otevírá okno do tvorby hvězd v jiných galaxiích.
Analýza dat ukázala, že, na rozdíl od naší galaxie, pozorované molekuly jsou soustředěny do malých, hustých jader plynu. To vysvětluje, proč bylo doposud tak těžké
pozorovat extragalaktické oblasti tvorby hvězd, obzvláště v málo hmotných galaxiích s nízkým obsahem těžších prvků. ALMA také zjistila, že se jádra v NGC 6822 chovají
velmi podobně hvězdným školkám v Mléčné dráze, což signalizuje, že fyzika tvorby hvězd v těchto malých galaxiích připomíná tu, kterou vidíme v naší galaxii.

Seeing things sideways | ESA/Hubble
http://www.spacetelescope.org/images/potw1711a/

This image from Hubble’s Wide Field Camera 3 (WFC3) shows NGC 1448, a spiral galaxy located about 50 million light-years from Earth
in the little-known constellation of Horologium (The Pendulum Clock). We tend to think of spiral galaxies as massive and roughly
circular celestial bodies, so this glittering oval does not immediately appear to fit the visual bill. What’s going on?

Imagine a spiral galaxy as a circular frisbee spinning gently in space. When we see it face on, our observations reveal a spectacular
amount of detail and structure — a great example from Hubble is the telescope’s view of Messier 51, otherwise known as the Whirlpool
Galaxy. However, the NGC 1448 frisbee is very nearly edge-on with respect to Earth, giving it an appearance that is more oval than
circular. The spiral arms, which curve out from NGC 1448’s dense core, can just about be seen.

Metabolism may be older than life itself and start spontaneously | New Scientist
https://www.newscientist.com/...75-metabolism-may-be-older-than-life-itself-and-start-spontaneously/

A set of chemical reactions occurring spontaneously in Earth’s early chemical environments could have provided the foundations upon which life evolved.

The discovery that a version of the Krebs cycle, which occurs in most living cells, can proceed in the absence of cellular proteins called enzymes suggests
that metabolism is older than life itself.

Metabolism describes the fiendishly complex network of reactions that enable organisms to generate energy and the molecules they need to survive, grow and
reproduce. The Krebs cycle – also known as the tricarboxylic acid (TCA) cycle – is at the heart of this network. It describes a circular chain of reactions
that generates precursors of amino acids and lipids used to build proteins and membranes, and molecules that help the cell to produce its energy.

But how did such a complex cycle develop in the first place?

One idea is that it began only after RNA, a fundamental building block of life, came into being. Metabolic reactions are catalysed by proteins called enzymes,
for which RNA provides the template – at least in modern cells. There is, however, a problem with this “RNA world” hypothesis: if the reactions didn’t already
occur immediately in early life forms and provide them with a survival advantage, then there would have been no selective pressure to drive the evolution of
enzymes. Furthermore, RNA itself is made from products of metabolism.

Building Magnetic Fields in White Dwarfs
http://aasnova.org/2017/03/10/building-magnetic-fields-in-white-dwarfs/

White dwarfs, the compact remnants left over at the end of low- and medium-mass stars’ lifetimes, are often found to have
magnetic fields with strengths ranging from thousands to billions of times that of Earth. But how do these fields form?

Incredible Saturn's upper atmosphere layers observed by Cassini on March 7th in far-red & ultraviolet wavelengths via Kevin M. Gill.
Assembled using raw uncalibrated far-red and ultraviolet (CB2, UV2) images taken by the Cassini spacecraft on March 7 2017.

Astronomy magazine - If Aliens Contact Us, We Won't Understand | Astronomy Magazine
http://astronomy.com/bonus/alien-contact

2016 gave us a fair number of false SETI detections. But lets imagine that this year it's the year.

Maybe it's first detected at a radio telescope in Russia, or perhaps an optical telescope in California. But in 2017, somewhere someone picks up
a signal. Skeptical astronomers alert their colleagues, yet sure enough, they're reading it out in telescopes around the world. It's too specific
or too weird to be a known natural phenomenon, and it repeats itself with suspiciously high fidelity over some interval. Cautiously, but excitedly,
the news gets out. We've received a message from the stars.

It's worth wondering: what would happen next?

Well, if you follow the logic of the renowned Polish philosopher and science fiction writer Stanisław Lem, after a lot of hubbub and frustration:
absolutely nothing. According to Lem's logic, our species may never be able to read or understand a message from extraterrestrials.