Tag Archives: Dark Matter

Free Astronomy Magazine – May-June 2017 Issue Available For Reading And Download

Greetings, fellow astrophiles!

The most recent issue of Free Astronomy Magazine (May-June, 2017) is available for your reading and downloading pleasure at www.astropublishing.com (click the link to go directly to the issue).

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 the issue has to offer, the Table of Contents is reproduced below.

May-June 2017

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

May-June 2017 – www.astropublishing.com/3FAM2017/

For those who want to jump right to the PDF download (27 MB), Click here: May-June 2017

NASA Space Place – The Loneliest Galaxy In The Universe

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 January, 2016.

By Dr. Ethan Siegel

2013february2_spaceplaceOur greatest, largest-scale surveys of the universe have given us an unprecedented view of cosmic structure extending for tens of billions of light years. With the combined effects of normal matter, dark matter, dark energy, neutrinos and radiation all affecting how matter clumps, collapses and separates over time, the great cosmic web we see is in tremendous agreement with our best theories: the Big Bang and General Relativity. Yet this understanding was only possible because of the pioneering work of Edwin Hubble, who identified a large number of galaxies outside of our own, correctly measured their distance (following the work of Vesto Slipher’s work measuring their redshifts), and discovered the expanding universe.

But what if the Milky Way weren’t located in one of the “strands” of the great cosmic web, where galaxies are plentiful and ubiquitous in many different directions? What if, instead, we were located in one of the great “voids” separating the vast majority of galaxies? It would’ve taken telescopes and imaging technology far more advanced than Hubble had at his disposal to even detect a single galaxy beyond our own, much less dozens, hundreds or millions, like we have today. While the nearest galaxies to us are only a few million light years distant, there are voids so large that a galaxy located at the center of one might not see another for a hundred times that distance.

While we’ve readily learned about our place in the universe from observing what’s around us, not everyone is as fortunate. In particular, the galaxy MCG+01-02-015 has not a single known galaxy around it for a hundred million light years in all directions. Were you to draw a sphere around the Milky Way with a radius of 100 million light years, we’d find hundreds of thousands of galaxies. But not MCG+01-02-015; it’s the loneliest galaxy ever discovered. Our Milky Way, like most galaxies, has been built up by mergers and accretions of many other galaxies over billions of years, having acquired stars and gas from a slew of our former neighbors. But an isolated galaxy like this one has only the matter it was born with to call its own.

Edwin Hubble made his universe-changing discovery using telescope technology from 1917, yet he would have found absolutely zero other galaxies at all were we situated at MCG+01-02-015’s location. The first visible galaxy wouldn’t have shown up until we had 1960s-level technology, and who knows if we’d have continued looking? If we were such a lonely galaxy, would we have given up the search, and concluded that our galaxy encompassed all of existence? Or would we have continued peering deeper into the void, eventually discovering our unusual location in a vast, expanding universe? For the inhabitants of the loneliest galaxy, we can only hope that they didn’t give up the search, and discovered the entire universe.

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

2016_01_NASA_loneliest.en

Caption: ESA/Hubble & NASA and N. Gorin (STScI); Acknowledgement: Judy Schmidt, of the loneliest void galaxy in the known: MCG+01-02-015.

About NASA Space Place

With articles, activities, crafts, games, and lesson plans, NASA Space Place encourages everyone to get excited about science and technology. Visit spaceplace.nasa.gov (facebook|twitter) to explore space and Earth science!

NASA News Digest: Space Science For 15 March – 26 March 2015

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

New Desktop Application Has Potential To Increase Asteroid Detection, Now Available To Public

RELEASE 15-041 (Click here for the full article) – 15 March 2015

2015april2_15_041A software application based on an algorithm created by a NASA challenge has the potential to increase the number of new asteroid discoveries by amateur astronomers.

Analysis of images taken of our solar system’s main belt asteroids between Mars and Jupiter using the algorithm showed a 15 percent increase in positive identification of new asteroids.

During a panel Sunday at the South by Southwest Festival in Austin, Texas, NASA representatives discussed how citizen scientists have made a difference in asteroid hunting. They also announced the release of a desktop software application developed by NASA in partnership with Planetary Resources, Inc., of Redmond, Washington. The application is based on an Asteroid Data Hunter-derived algorithm that analyzes images for potential asteroids. It’s a tool that can be used by amateur astronomers and citizen scientists.

The new asteroid hunting application can be downloaded at: topcoder.com/asteroids

For information about NASA’s Asteroid Grand Challenge, visit: www.nasa.gov/asteroidinitiative

NASA Spacecraft Detects Aurora And Mysterious Dust Cloud Around Mars

RELEASE 15-045 (Click here for the full article) – 18 March 2015

2015april2_15_045aNASA’s Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft has observed two unexpected phenomena in the Martian atmosphere: an unexplained high-altitude dust cloud and aurora that reaches deep into the Martian atmosphere.

The presence of the dust at orbital altitudes from about 93 miles (150 kilometers) to 190 miles (300 kilometers) above the surface was not predicted. Although the source and composition of the dust are unknown, there is no hazard to MAVEN and other spacecraft orbiting Mars.

“If the dust originates from the atmosphere, this suggests we are missing some fundamental process in the Martian atmosphere,” said Laila Andersson of the University of Colorado’s Laboratory for Atmospherics and Space Physics (CU LASP), Boulder, Colorado.

For images related to the findings, visit: http://www.nasa.gov/maven

NASA’s SOFIA Finds Missing Link Between Supernovae And Planet Formation

RELEASE 15-044 (Click here for the full article) – 19 March 2015

2015april2_15_044aUsing NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA), an international scientific team discovered that supernovae are capable of producing a substantial amount of the material from which planets like Earth can form.

These findings are published in the March 19 online issue of Science magazine.

“Our observations reveal a particular cloud produced by a supernova explosion 10,000 years ago contains enough dust to make 7,000 Earths,” said Ryan Lau of Cornell University in Ithaca, New York.

The research team, headed by Lau, used SOFIA’s airborne telescope and the Faint Object InfraRed Camera for the SOFIA Telescope, FORCAST, to take detailed infrared images of an interstellar dust cloud known as Supernova Remnant Sagittarius A East, or SNR Sgr A East.

For more information about SOFIA, visit: www.nasa.gov/sofia or www.dlr.de/en/sofia

For information about SOFIA’s science mission and scientific instruments, visit: www.sofia.usra.edu or www.dsi.uni-stuttgart.de/index.en.html

NASA’s Opportunity Mars Rover Finishes Marathon, Clocks In At Just Over 11 Years

RELEASE 15-049 (Click here for the full article) – 24 March 2015

2015april2_15_049cThere was no tape draped across a finish line, but NASA is celebrating a win. The agency’s Mars Exploration Rover Opportunity completed its first Red Planet marathon Tuesday — 26.219 miles (42.195 kilometers) – with a finish time of roughly 11 years and two months.

“This is the first time any human enterprise has exceeded the distance of a marathon on the surface of another world,” said John Callas, Opportunity project manager at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California. “A first time happens only once.”

The rover team at JPL plans a marathon-length relay run at the laboratory next week to celebrate.

The long-lived rover surpassed the marathon mark during a drive of 153 feet (46.5 meters). Last year, Opportunity became the long-distance champion of all off-Earth vehicles when it topped the previous record set by the former Soviet Union’s Lunokhod 2 moon rover.

For more information about Opportunity, visit www.nasa.gov/rovers

Follow the project on social media at: twitter.com/MarsRovers and www.facebook.com/mars.rovers

NASA’s Hubble, Chandra Find Clues That May Help Identify Dark Matter

RELEASE 15-046 (Click here for the full article) – 26 March 2015

2015april2_15_046Using observations from NASA’s Hubble Space Telescope and Chandra X-ray Observatory, astronomers have found that dark matter does not slow down when colliding with itself, meaning it interacts with itself less than previously thought. Researchers say this finding narrows down the options for what this mysterious substance might be.

Dark matter is an invisible matter that makes up most of the mass of the universe. Because dark matter does not reflect, absorb or emit light, it can only be traced indirectly by, such as by measuring how it warps space through gravitational lensing, during which the light from a distant source is magnified and distorted by the gravity of dark matter.

To learn more about dark matter and test such theories, researchers study it in a way similar to experiments on visible matter — by watching what happens when it bumps into other objects. In this case, the colliding objects under observation are galaxy clusters.

For images and more information about the Hubble Space Telescope, visit: www.nasa.gov/hubble

For more Chandra images, multimedia and related materials, visit: www.nasa.gov/mission_pages/chandra/main