USRA | Arecibo Observatory casts new light on cosmic microwave background observed by WMAP and PLANCK spacecraft: Bringing scientists one step closer to understanding the small-scale structure in the cosmic microwave background
http://www.usra.edu/news/pr/2017/cosmicmicrowave/

Arecibo Observatory observations of galactic neutral hydrogen structure confirm the discovery of an unexpected contribution to the measurements of the cosmic microwave
background observed by the WMAP and Planck spacecraft. An accurate understanding of the foreground (galactic) sources of radiation observed by these two spacecraft is
essential for extracting information about the small-scale structure in the cosmic microwave background believed to be indicative of events in the early universe.

The new source of radiation in the 22 to 100 GHz range observed by WMAP and Planck appears to be emission from cold electrons (known as free-free emission). While
cosmologists have corrected for this type of radiation from hot electrons associated with galactic nebulae where the source temperatures are thousands of degrees,
the new model requires electron temperatures more like a few 100 K.

The spectrum of the small-scale features observed by WMAP and Planck in this frequency range is very nearly flat - a finding consistent with the sources being associated
with the Big Bang. At first glance it appears that the spectrum expected from the emission by cold galactic electrons, which exist throughout interstellar space, would
be far too steep to fit the data. However, if the sources of emission have a small angular size compared with the beam width used in the WMAP and Planck spacecraft, the
signals they record would be diluted. The beam widths increase with lower frequency, and the net result of this "beam dilution" is to produce an apparently flat spectrum
in the 22 to 100 GHz range.

The model invoking the emission from cold electrons not only gives the observed flat spectrum usually attributed to cosmic sources but also predicts values for the angular
scale and temperature for the emitting volumes. Those predictions can then be compared with observations of galactic structure revealed in the Galactic Arecibo L-Band Feed
Array (GALFA) HI survey.

"The interstellar medium is much more surprising and important than we have given it credit for," noted Dr. Joshua Peek, an astronomer at the Space Telescope Science
Institute and a co-investigator on the GALFA-HI survey. "Arecibo, with its combination of large area and high resolution, remains a spectacular and cutting edge tool
for comparing ISM maps to cosmological data sets."

The angular scales of the smallest features observed in neutral hydrogen maps made at Arecibo and the temperature of the apparently associated gas both match the model
calculations extremely well. So far only three well-studied areas have been analyzed in such detail, but more work is being planned.

"It was the agreement between the model predictions and the GALFA-HI observations that convinced me that we might be onto something," noted Dr. Joan Schmelz, Director,
Universities Space Research Association (USRA) at Arecibo Observatory and a coauthor on the paper. "We hope that these results help us understand the true cosmological
nature of Planck and WMAP data."

The data suggest that the structure and physics of diffuse interstellar matter, in particular of cold hydrogen gas and associated electrons, may be more complex than
heretofore considered. Such complexities need to be taken into account in order to produce better foreground masks for application to the high-frequency continuum
observations of Planck and WMAP in the quest for a cosmologically significant signal.

Working at Subaru Telescope 3. Instrumentation & Electronics
https://www.youtube.com/watch?v=shCMkZI9LuQ

USRA | The Mystery of Part-Time Pulsars
http://www.usra.edu/news/pr/2017/pulsar/

A new discovery has upended the widely held view that all pulsars are orderly ticking clocks of the universe.
A survey done at the Arecibo Observatory in Puerto Rico has fortuitously discovered two extremely strange pulsars
that undergo a "cosmic vanishing act." Sometimes they are there, and then for very long periods of time, they are not.

Recognizing the existence of this strange behavior was fortuitous in itself. It took great patience on the part of
a team of radio astronomers at Jodrell Bank in the UK led by Professor Andrew Lyne of the University of Manchester
to confirm the existence of these mostly invisible pulsars.

Intermittent pulsars are a rarely observed population of pulsars, which have two states -- one when they pulse like
normal pulsars (the ON state), and another when they mysteriously fail to work, producing no radio waves at all (the
OFF state). "They switch instantaneously between the states," notes Lyne. "They're ON and then they're gone,
disappearing without any apparent warning."

A 34-member pulsar study team, including Dr. Andrew Seymour, a USRA postdoc at Arecibo, used the 7-beam receiver to
conduct routine pulsar searches in what they call the PALFA (Pulsar Arecibo L-Band Feed Array) Survey. The two recently
discovered intermittent pulsars spend most of their time in the OFF state. Three other similar pulsars are also known,
but they are mostly ON.

VIRGO: no já se právě vylekala (pozitivně), že se chystá nějaký great oznámení, co se toho týče... :) no takže takhle taky dobrý :)

VIRGO: to je nádhera, i ta andromeda níže! krása prostě :)

VIRGO:
VIRGO: co to co to co to??

VIRGO: Mise Lucy a Psyche byly vybrány pro program Discovery. Jupí!!

NASA’s New Discovery Missions
https://www.youtube.com/watch?v=nYdCU1QQQro


NASA has selected two missions that have the potential to open new windows on one of the earliest eras in the history of our solar system –
a time less than 10 million years after the birth of our sun. The missions, known as Lucy and Psyche, were chosen from five finalists and
will proceed to mission formulation, with the goal of launching in 2021 and 2023, respectively.

https://www.nasa.gov/press-release/nasa-selects-two-missions-to-explore-the-early-solar-system

How much light does a supernova shed on the history of universe?

New research by cosmologists at the University of Chicago and Wayne State University confirms the accuracy of Type Ia supernovae in measuring
the pace at which the universe expands. The findings support a widely held theory that the expansion of the universe is accelerating and such
acceleration is attributable to a mysterious force known as dark energy. The findings counter recent headlines that Type Ia supernova cannot
be relied upon to measure the expansion of the universe.

Using light from an exploding star as bright as entire galaxies to determine cosmic distances led to the 2011 Nobel Prize in physics. The method
relies on the assumption that, like lightbulbs of a known wattage, all Type Ia supernovae are thought to have nearly the same maximum brightness
when they explode. Such consistency allows them to be used as beacons to measure the heavens. The weaker the light, the farther away the star. But
the method has been challenged in recent years because of findings the light given off by Type Ia supernovae appears more inconsistent than expected.

“The data that we examined are indeed holding up against these claims of the demise of Type Ia supernovae as a tool for measuring the universe,”
said Daniel Scolnic, a postdoctoral scholar at UChicago’s Kavli Institute for Cosmological Physics and co-author of the new research published in
Monthly Notices of the Royal Astronomical Society. “We should not be persuaded by these other claims just because they got a lot of attention,
though it is important to continue to question and strengthen our fundamental assumptions.”

Research reinforces role of supernovae in clocking the universe | UChicago News
https://news.uchicago.edu/article/2017/01/03/research-reinforces-role-supernovae-clocking-universe