https://www.nasa.gov/image-feature/new-day

"A view of the sunrise from the ISS is a perfect start to a new day," so said @Anton_Astrey, otherwise known as cosmonaut
Anton Shkaplerov, who is currently stationed aboard the International Space Station, orbiting 250 miles above the Earth.

Hurá!!

První segmenty primárního zrcadla dalekohledu ELT úspěšně odlity | ESO Česko
http://www.eso.org/public/czechrepublic/news/eso1801/?lang

Německá firma SCHOTT ve své továrně ve městě Mainz úspěšně odlila prvních šest segmentů primárního zrcadla pro dalekohled ELT. Hlavní zrcadlo dalekohledu ELT bude
mít průměr 39 m a bude ho tvořit celkem 798 šestiúhelníkových segmentů. Po dokončení v roce 2024 by se dalekohled ELT měl stát největším optickým teleskopem na světě.

Primární zrcadlo připravovaného dalekohledu ELT (Extremely Large Telescope) bude s průměrem 39 m zdaleka největším, jaké bylo kdy osazeno v jakémkoliv dalekohledu
pro viditelnou nebo infračervenou oblast. Takto velké zrcadlo je však příliš velké na to, aby bylo možné ho vyrobit z jednoho kusu skla. Proto bude sestaveno ze 798
šestiúhelníkových segmentů o průměru 1,4 m a tloušťce 5 cm. Jednotlivé díly budou uloženy tak, aby mohly pracovat společně jako jedna optická plocha, která posbírá
dvacetmilionkrát více světla než lidské oko.

ESOcast Light 145: First ELT Main Mirror Segments Successfully Cast
https://www.youtube.com/watch?v=85Qcbn8nlaM

First PEPSI data release — English
http://www.aip.de/en/news/science/first-pepsi-data-release

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona
released its first batch of high-spectral resolution data to the scientific community. In a series of three papers in
the European journal Astronomy & Astrophysics, the PEPSI team presents a new spectral atlas of the Sun, a total of 48
atlases of bright benchmark stars, and a detailed analysis of the chemical abundances of the 10-billion year old planet-
system host Kepler-444.

Saturn's moon Titan sports Earth-like features | Cornell Chronicle
http://news.cornell.edu/stories/2018/01/saturns-moon-titan-sports-earth-features

Using the now-complete Cassini data set, Cornell astronomers have created a new global topographic map of Saturn’s moon Titan that has opened new windows into
understanding its liquid flows and terrain. Two new papers, published Dec. 2 in Geophysical Review Letters, describe the map and discoveries arising from it.

Creating the map took about a year, according to doctoral student Paul Corlies, first author on “Titan’s Topography and Shape at the End of the Cassini Mission.”
The map combines all of the Titan topography data from multiple sources. Since only about 9 percent of Titan has been observed in relatively high-resolution
topography, with 25-30 percent of the topography imaged in lower resolution, the remainder of the moon was mapped using an interpolation algorithm and a global
minimization process, which reduced errors such as those arising from spacecraft location.

The map revealed several new features on Titan, including new mountains, none higher than 700 meters. The map also provides a global view of the highs and lows
of Titan’s topography, which enabled the scientists to confirm that two locations in the equatorial region of Titan are in fact depressions that could be either
ancient, dried seas or cryovolcanic flows. The map also revealed that Titan is a little bit flatter – more oblate – than was previously known, which suggests
there is more variability in the thickness of Titan’s crust than previously thought.

W. M. Keck Observatory Achieves First Light with NIRES W. M. Keck Observatory
http://www.keckobservatory.org/recent/entry/NIRES

Astronomers at W. M. Keck Observatory have successfully met a major milestone after capturing the very first
science data from Keck Observatory’s newest instrument, the Caltech-built Near-Infrared Echellette Spectrometer (NIRES).

The Keck Observatory-Caltech NIRES team just completed the instrument’s first set of commissioning observations and achieved
“first light” with a spectral image of the planetary nebula NGC 7027.

“The Keck Observatory continually strives to provide instrumentation that meets the high aspirations of our scientific
community and responds to changing scientific needs,” said Keck Observatory Director Hilton Lewis. “NIRES is expected to be
one of the most efficient single-object, near-infrared spectrographs on an eight to ten-meter telescope, designed to study
explosive, deep sky phenomena such as supernovae and gamma ray bursts, a capability that is in high demand.”

“The power of NIRES is that it can cover a whole spectral range simultaneously with one observation,” said Keith Matthews,
the instrument’s principal investigator and a chief instrument scientist at Caltech. “It’s a cross-dispersed spectrograph
that works in the infrared from where the visual cuts off out to 2.4 microns where the background from the thermal emission
gets severe.”

Large asteroid 2018 AH flew past Earth at 0.77 LD, 2 days after discovery

A relatively large newly discovered asteroid designated 2018 AH flew past Earth at 0.77 LD / 0.00199 AU (~297 699 km / 184 982 miles) on January 2, 2018.
This is the 1st known asteroid to flyby Earth within 1 LD this year, 54th since January 1, 2017 and the largest within 1 LD since 2011.

2018 AH was first observed at ATLAS-MLO, Mauna Loa on January 4, 2018, two days after its close approach to Earth. The closest approach to Earth took place
at 04:25 UTC on January 2 at a speed (relative to the Earth) of 13.76 km/s.

It belongs to the Apollo group of asteroids, the most common one, and it has an estimated diameter of 84 - 190 m (275 - 693 feet), making it the largest
known near-Earth object to flyby Earth within 1 lunar distance since 2011.

It is also the 9th largest known near-Earth object (asteroids + comets) to flyby Earth within 1 lunar distance ever. Over the past 18 years, only 2 asteroids
larger than 2018 AH flew past us this close and 8 since 1918.

As of January 5, 2018, there are 17 566 known near-Earth objects around our planet, 17 460 of them are asteroids. Of the total number of known NEOs,
7 999 have an estimated diameter roughly 140 m (460 feet) or larger, including 2018 AH.

Gravitational Waves Measure the Universesu201801 | www.cfa.harvard.edu/
https://www.cfa.harvard.edu/news/su201801

The direct detection of gravitational waves from at least five sources during the past two years offers spectacular confirmation of Einstein's model of gravity and space-time. Modeling of these events has also
provided information on massive star formation, gamma-ray bursts, neutron star characteristics, and (for the first time) verification of theoretical ideas about how the very heavy elements, like gold, are produced.

Astronomers have now used a single gravitational wave event (GW170817) to measure the age of the universe. CfA astronomers Peter Blanchard, Tarreneh Eftekhari, Victoria Villar, and Peter Williams were members
of a team of 1314 scientists from around the world who contributed to the detection of gravitational waves from a merging pair of binary neutron stars, followed by the detection of gamma-rays, and then the
identification of the origin of the cataclysm in a source in the galaxy NGC4993 spotted in images taken with various time delays at wavelengths from the X-ray to the radio.

An analysis of the gravitational waves from this event infers their intrinsic strength. The observed strength is less, implying (because the strength diminishes with distance from the source) that the source
is about 140 million light-years away. NGC4993, its host galaxy, has an outward velocity due to the expansion of the universe that can be measured from its spectral lines. Knowing how far away it is and how fast
the galaxy is moving from us allows scientists to calculate the time since the expansion began – the age of the universe: between about 11.9 and 15.7 billion years given the experimental uncertainties.

Plot thickens as New Horizons moves within year of next flyby – Astronomy Now
https://astronomynow.com/2018/01/06/plot-thickens-as-new-horizons-moves-within-year-of-next-flyby/

The final days before NASA’s New Horizons probe barrels in on its next destination on Jan. 1, 2019, should prove eventful, with scientists trying
to sort out whether a distant mini-world detected by the Hubble Space Telescope more than three years ago may actually be a swarm of icy objects.

New Horizons’ sharp-eyed camera will serve as a look-out as the spacecraft makes a speedy approach toward 2014 MU69, the official name for the mission’s
next target. Scientists will search for moons and icy debris, discoveries which could add intrigue to the one-shot encounter on New Year’s Day 2019.

Krásný kousek!

NASA rover spots strange 'stick-like figures' on Mars - CNET
https://www.cnet.com/au/news/nasa-mars-rover-curiosity-stick-like-figures-crystals/

While the rest of us were on vacation over the holidays, the Mars Curiosity rover kept plugging away at its mission of exploring the Red Planet. It put some of the time
into inspecting and photographing a set of fascinating stick-like formations on the Martian ground. The rover team tweeted a good look at the small objects on Wednesday.

https://www.nasa.gov/image-feature/jpl/pia21973/high-above-jupiter-s-clouds

NASA’s Juno spacecraft was a little more than one Earth diameter from Jupiter when it captured this mind-bending, color-enhanced view of the planet’s tumultuous atmosphere.

Jupiter completely fills the image, with only a hint of the terminator (where daylight fades to night) in the upper right corner, and no visible limb (the curved edge of the planet).

Juno took this image of colorful, turbulent clouds in Jupiter’s northern hemisphere on Dec. 16, 2017 at 9:43 a.m. PST (12:43 p.m. EST) from 8,292 miles (13,345 kilometers) above
the tops of Jupiter’s clouds, at a latitude of 48.9 degrees. The spatial scale in this image is 5.8 miles/pixel (9.3 kilometers/pixel).

Citizen scientists Gerald Eichstädt and Seán Doran processed this image using data from the JunoCam imager.

How I discovered the origins of the cigar-shaped alien 'asteroid' 'Oumuamua
https://theconversation.com/...covered-the-origins-of-the-cigar-shaped-alien-asteroid-oumuamua-89577

With a hyperbolic trajectory around the Sun, `Oumuamua is the first confirmed interstellar object. However, its origin is poorly known. By simulating the orbits of 0.23 million local stars,
we find 109 encounters with periastron less than 5 pc. `Oumuamua's low peculiar velocity is suggestive of its origin from a young stellar association with similar velocity. In particular,
we find that `Oumuamua would have had slow encounters with at least five young stars belonging to the Local Association thus suggesting these as plausible sites for formation and ejection.
In addition to an extremely elongated shape, the available observational data for `Oumuamua indicates a red colour suggestive of a potentially organic-rich and activity-free surface.

[1711.08800] `Oumuamua as a messenger from the Local Association
https://arxiv.org/abs/1711.08800