Tag Archives: Quasar

Free Astronomy Magazine – November-December 2015 AND January-February 2016 Issues Available For Reading And Download

2016_fam_coversGreetings fellow astrophiles!

I must have missed an email a few months back – The *two* most recent issues of Free Astronomy Magazine are available for your reading and downloading pleasure at www.astropublishing.com.

Free Astronomy Magazine was featured as the first of a series of articles on great free online content for amateur astronomers (see A Universe Of Free Resources Part 1) and we’ll be keeping track of future publications under the Online Resources category on the CNYO website.

You can find previous Free Astronomy Magazine issues by checking out our Free Astronomy Magazine Category (or look under the Education link in our menu).

For those wanting a quick look at what these issues have to offer, the Table of Contents are reproduced below (click on each for larger views).

January-February 2016

The web browser-readable versions of the issue can be found here:

Jan/Feb 2016 – www.astropublishing.com/FAM-1-2016/index.html

For those who want to jump right to the PDF download (50 MB), Click below:

January-February 2016

2016janfeb

November-December 2015

The web browser-readable versions of the issue can be found here:

Nov/Dec 2015 – www.astropublishing.com/FreeAstronomyMagazine_NovDec2015/index.html

For those who want to jump right to the PDF download (50 MB), Click below:

November-December 2015

2015novdec

NASA News Digest: Space Science For 22 July – 31 July 2014

Greetings fellow astrophiles,

The NASA News service provides up-to-date announcements of NASA policy, news events, and space science. A recent selection of space science articles are provided below, including direct links to the full announcements. Those interested in receiving these news announcements directly from NASA can subscribe to their service by sending an email to:

hqnews-request@newsletters.nasa.gov?subject=subscribe

NASA’s Chandra X-Ray Observatory Celebrates 15th Anniversary

RELEASE 14-196 (Click here for the full article) – 22 July 2014

14_196_smallFifteen years ago, NASA’s Chandra X-ray Observatory was launched into space aboard the Space Shuttle Columbia. Since its deployment on July 23, 1999, Chandra has helped revolutionize our understanding of the universe through its unrivaled X-ray vision.

Chandra, one of NASA’s current “Great Observatories,” along with the Hubble Space Telescope and Spitzer Space Telescope, is specially designed to detect X-ray emission from hot and energetic regions of the universe.

With its superb sensitivity and resolution, Chandra has observed objects ranging from the closest planets and comets to the most distant known quasars. It has imaged the remains of exploded stars, or supernova remnants, observed the region around the supermassive black hole at the center of the Milky Way, and discovered black holes across the universe. Chandra also has made a major advance in the study of dark matter by tracing the separation of dark matter from normal matter in collisions between galaxy clusters. It also is contributing to research on the nature of dark energy.

Additional details, images and an animation are available at: www.ciclops.org/view_event/202
More information about Cassini is available at: www.nasa.gov/cassini and saturn.jpl.nasa.gov

Hubble Finds Three Surprisingly Dry Exoplanets

RELEASE 14-197 (Click here for the full article) – 24 July 2014

14_197_smallAstronomers using NASA’s Hubble Space Telescope have gone looking for water vapor in the atmospheres of three planets orbiting stars similar to the sun — and have come up nearly dry.
The three planets, known as HD 189733b, HD 209458b, and WASP-12b, are between 60 and 900 light-years away from Earth and were thought to be ideal candidates for detecting water vapor in their atmospheres because of their high temperatures where water turns into a measurable vapor.

These so-called “hot Jupiters” are so close to their star they have temperatures between 1,500 and 4,000 degrees Fahrenheit, however, the planets were found to have only one-tenth to one one-thousandth the amount of water predicted by standard planet-formation theories.

For images and more information about Hubble, visit: www.nasa.gov/hubble and hubblesite.org/news/2014/36

Cassini Spacecraft Reveals 101 Geysers and more on Icy Saturn Moon

RELEASE 14-203 (Click here for the full article) – 28 July 2014

14_203_smallScientists using mission data from NASA’s Cassini spacecraft have identified 101 distinct geysers erupting on Saturn’s icy moon Enceladus. Their analysis suggests it is possible for liquid water to reach from the moon’s underground sea all the way to its surface.

These findings, and clues to what powers the geyser eruptions, are presented in two articles published in the current online edition of the Astronomical Journal.

Over a period of almost seven years, Cassini’s cameras surveyed the south polar terrain of the small moon, a unique geological basin renowned for its four prominent “tiger stripe” fractures and the geysers of tiny icy particles and water vapor first sighted there nearly 10 years ago. The result of the survey is a map of 101 geysers, each erupting from one of the tiger stripe fractures, and the discovery that individual geysers are coincident with small hot spots. These relationships pointed the way to the geysers’ origin.

Additional details, images and an animation are available at: www.ciclops.org/view_event/202

More information about Cassini is available at: www.nasa.gov/cassini and saturn.jpl.nasa.gov

Hubble Shows Farthest Lensing Galaxy Yields Clues to Early Universe

RELEASE 14-205 (Click here for the full article) – 31 July 2014

14_205_smallAstronomers using NASA’s Hubble Space Telescope have unexpectedly discovered the most distant galaxy that acts as a cosmic magnifying glass. Seen here as it looked 9.6 billion years ago, this monster elliptical galaxy breaks the previous record-holder by 200 million years.

These “lensing” galaxies are so massive that their gravity bends, magnifies, and distorts light from objects behind it, a phenomenon called gravitational lensing. Finding one in such a small area of the sky is so rare that you would normally have to survey a region hundreds of times larger to find just one.

For images and more information about Hubble, visit: www.nasa.gov/hubble and hubblesite.org/news/2014/33

NASA’s Fermi Space Telescope Reveals New Source of Gamma Rays

RELEASE 14-209 (Click here for the full article) – 31 July 2014

14_209_smallObservations by NASA’s Fermi Gamma-ray Space Telescope of several stellar eruptions, called novae, firmly establish these relatively common outbursts almost always produce gamma rays, the most energetic form of light.

“There’s a saying that one is a fluke, two is a coincidence, and three is a class, and we’re now at four novae and counting with Fermi,” said Teddy Cheung, an astrophysicist at the Naval Research Laboratory in Washington, and the lead author of a paper reporting the findings in the Aug. 1 edition of the journal Science.

A nova is a sudden, short-lived brightening of an otherwise inconspicuous star caused by a thermonuclear explosion on the surface of a white dwarf, a compact star not much larger than Earth. Each nova explosion releases up to 100,000 times the annual energy output of our sun. Prior to Fermi, no one suspected these outbursts were capable of producing high-energy gamma rays, emission with energy levels millions of times greater than visible light and usually associated with far more powerful cosmic blasts.

For more information about Fermi, visit: www.nasa.gov/fermi

NASA Space Place – Old Tool, New Use: GPS and the Terrestrial Reference Frame

Poster’s Note: One of the many under-appreciated aspects of NASA is the extent to which it publishes quality science content for children and Ph.D.’s alike. NASA Space Place has been providing general audience articles for quite some time that are freely available for download and republishing. Your tax dollars help promote science! The following article was provided for reprinting in March, 2014.

By Alex H. Kasprak

2013february2_spaceplaceFlying over 1300 kilometers above Earth, the Jason 2 satellite knows its distance from the ocean down to a matter of centimeters, allowing for the creation of detailed maps of the ocean’s surface. This information is invaluable to oceanographers and climate scientists. By understanding the ocean’s complex topography—its barely perceptible hills and troughs—these scientists can monitor the pace of sea level rise, unravel the intricacies of ocean currents, and project the effects of future climate change.

But these measurements would be useless if there were not some frame of reference to put them in context. A terrestrial reference frame, ratified by an international group of scientists, serves that purpose. “It’s a lot like air,” says JPL scientist Jan Weiss. “It’s all around us and is vitally important, but people don’t really think about it.” Creating such a frame of reference is more of a challenge than you might think, though. No point on the surface of Earth is truly fixed.

To create a terrestrial reference frame, you need to know the distance between as many points as possible. Two methods help achieve that goal. Very-long baseline interferometry uses multiple radio antennas to monitor the signal from something very far away in space, like a quasar. The distance between the antennas can be calculated based on tiny changes in the time it takes the signal to reach them. Satellite laser ranging, the second method, bounces lasers off of satellites and measures the two-way travel time to calculate distance between ground stations.

Weiss and his colleagues would like to add a third method into the mix—GPS. At the moment, GPS measurements are used only to tie together the points created by very long baseline interferometry and satellite laser ranging together, not to directly calculate a terrestrial reference frame.

“There hasn’t been a whole lot of serious effort to include GPS directly,” says Weiss. His goal is to show that GPS can be used to create a terrestrial reference frame on its own. “The thing about GPS that’s different from very-long baseline interferometry and satellite laser ranging is that you don’t need complex and expensive infrastructure and can deploy many stations all around the world.”

Feeding GPS data directly into the calculation of a terrestrial reference frame could lead to an even more accurate and cost effective way to reference points geospatially. This could be good news for missions like Jason 2. Slight errors in the terrestrial reference frame can create significant errors where precise measurements are required. GPS stations could prove to be a vital and untapped resource in the quest to create the most accurate terrestrial reference frame possible. “The thing about GPS,” says Weiss, “is that you are just so data rich when compared to these other techniques.”

You can learn more about NASA’s efforts to create an accurate terrestrial reference frame here: space-geodesy.nasa.gov/.

Kids can learn all about GPS by visiting http://spaceplace.nasa.gov/gps and watching a fun animation about finding pizza here: spaceplace.nasa.gov/gps-pizza.

This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

2014mar15_jason2

Caption: Artist’s interpretation of the Jason 2 satellite. To do its job properly, satellites like Jason 2 require as accurate a terrestrial reference frame as possible. Image courtesy: NASA/JPL-Caltech.

About NASA Space Place

The goal of the NASA Space Place is “to inform, inspire, and involve children in the excitement of science, technology, and space exploration.” More information is available at their website: http://spaceplace.nasa.gov/