Astronomical Organizations

New Study Challenges Long-Held Theory of Fate of Mars’ Water

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Grey Hautaluoma / Alana Johnson
NASA Headquarters, Washington
grey.hautaluoma-1@nasa.gov / alana.r.johnson@nasa.gov

Andrew Good
Jet Propulsion Laboratory, Pasadena, Calif.
andrew.c.good@jpl.nasa.gov

This global view of Mars is composed of about 100 Viking Orbiter images. Credit: NASA/JPL-Caltech/USGS

The new science results indicate that a large quantity of the Red Planet’s water is trapped in its crust rather than having escaped into space.

Billions of years ago, according to geological evidence, abundant water flowed across Mars and collected into pools, lakes, and deep oceans. New NASA-funded research shows a substantial quantity of its water – between 30 and 99% – is trapped within minerals in the planet’s crust, challenging the current theory that due to the Red Planet’s low gravity, its water escaped into space.

Early Mars was thought to have enough water to have covered the whole planet in an ocean roughly 100 to 1,500 meters (330 to 4,920 feet) deep – a volume roughly equivalent to half of Earth’s Atlantic Ocean. While some of this water undeniably disappeared from Mars via atmospheric escape, the new findings, published in the latest issue of Science, conclude it does not account for most of its water loss.

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New Clues About How Ancient Galaxies Lit up the Universe

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Calla Cofield
Jet Propulsion Laboratory, Pasadena, Calif.
calla.e.cofield@jpl.nasa.gov 

 

This deep-field view of the sky (center) taken by NASA’s Hubble and Spitzer space telescopes is dominated by galaxies – including some very faint, very distant ones – circled in red. The bottom right inset shows the light collected from one of those galaxies during a long-duration observation.Credit: NASA/JPL-Caltech/ESA/Spitzer/P. Oesch/S. De Barros/I.Labbe

 

NASA’s Spitzer Space Telescope has revealed that some of the universe’s earliest galaxies were brighter than expected. The excess light is a byproduct of the galaxies releasing incredibly high amounts of ionizing radiation. The finding offers clues to the cause of the Epoch of Reionization, a major cosmic event that transformed the universe from being mostly opaque to the brilliant starscape seen today. 

In a new study (Royal Astronomical Society), researchers report on observations of some of the first galaxies to form in the universe, less than 1 billion years after the big bang (or a little more than 13 billion years ago). The data show that in a few specific wavelengths of infrared light, the galaxies are considerably brighter than scientists anticipated. The study is the first to confirm this phenomenon for a large sampling of galaxies from this period, showing that these were not special cases of excessive brightness, but that even average galaxies present at that time were much brighter in these wavelengths than galaxies we see today. 

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NASA, FEMA, International Partners Plan Asteroid Impact Exercise

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Dwayne Brown / JoAnna Wendel 

NASA Headquarters, Washington 

 

DC Agle 

Jet Propulsion Laboratory, Pasadena, Calif.

 

 

 

The Manicouagan impact crater in Quebec, Canada, is one of many reminders that asteroids have impacted Earth. Although large impacts are rare, it’s important to be prepared. That’s why NASA, other U.S. agencies and international partners gather periodically to simulate impact scenarios and discuss the best course of action for disaster mitigation. Credit: International Space Station

 

While headlines routinely report on “close shaves” and “near-misses” when near-Earth objects (NEOs) such as asteroids or comets pass relatively close to Earth, the real work of preparing for the possibility of a NEO impact with Earth goes on mostly out of the public eye.

 

For more than 20 years, NASA and its international partners have been scanning the skies for NEOs, which are asteroids and comets that orbit the Sun and come within 30 million miles (50 million kilometers) of Earth’s orbit. International groups, such as NASA’s Planetary Defense Coordination Office (PDCO), the European Space Agency’s Space Situational Awareness-NEO Segment and the International Asteroid Warning Network (IAWN) have made better communication of the hazards posed by NEOs a top priority.


 

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SPACE-TIME: The Missing Mass Mystery

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By George McGinn
Cosmology and Space Research Institute

 

This illustration shows the three steps astronomers used to measure the universe’s expansion rate to an unprecedented accuracy, reducing the total uncertainty to 2.4 percent. Credits: NASA, ESA, A. Field (STScI), and A. Riess (STScI/JHU)

 

I don’t believe in Dark Matter or Dark Energy. Even the new Dark Flow.

While I would like to think that our cosmologists and physicists got lazy, what I really believe is they just created placeholders, misleading ones at that, but I wholeheartedly agree that we have no idea what they are, do, or if they are even real.
 
I like to watch PBS Space-Time on YouTube, as Host and Physicist Matt O’Dowd* would discuss topics that are relevant today in our field, and there is something for everyone, from the novice to the professionals. And while he sometimes will do numerous episodes, like on Dark Matter and Dark Energy, I don’t always agree with what he’s talking about.
 
But after watching the episode below (it is an older one, but the information is as relevant today as it was when it was reported on), I had to post a reply (which is below) and a short explanation, as I am working on a research paper on Dark Matter, Dark Energy, and the new voodoo science of “Dark Flow,” which I will address in another post here.
 
 

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Dark Matter Less Influential in Galaxies in Early Universe

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Reinhard Genzel
Director, Max-Planck-Institut für extraterrestrische Physik
Garching bei München, Germany
March 15, 2017 

 

New observations indicate that massive, star-forming galaxies during the peak epoch of galaxy formation, 10 billion years ago, were dominated by baryonic or “normal” matter. This is in stark contrast to present-day galaxies, where the effects of mysterious dark matter seem to be much greater. This surprising result was obtained using ESO’s Very Large Telescope and suggests that dark matter was less influential in the early Universe than it is today. The research is presented in four papers, one of which will be published in the journal Nature this week.

 

VLT observations of distant galaxies suggest they were dominated by normal matter


We see normal matter as brightly shining stars, glowing gas and clouds of dust. But the more elusive dark matter does not emit, absorb or reflect light and can only be observed via its gravitational effects. The presence of dark matter can explain why the outer parts of nearby spiral galaxies rotate more quickly than would be expected if only the normal matter that we can see directly were present [1].

Now, an international team of astronomers led by Reinhard Genzel at the Max Planck Institute for Extraterrestrial Physics in Garching, Germany have used the KMOS and SINFONI instruments at ESO’s Very Large Telescope in Chile [2] to measure the rotation of six massive, star-forming galaxies in the distant Universe, at the peak of galaxy formation 10 billion years ago.

What they found was intriguing: unlike spiral galaxies in the modern Universe, the outer regions of these distant galaxies seem to be rotating more slowly than regions closer to the core — suggesting there is less dark matter present than expected [3].

 

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Charting the Milky Way From the Inside Out

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Charting the Milky Way From the Inside Out
Imagine trying to create a map ofyour house while confined to only the living room. You might peek through the doors into other rooms or look for light spilling in through the windows. But, in the end, the walls and lack of visibility would largely prevent you from seeing the big picture.
 


The job of mapping our own Milky Way galaxy from planet Earth, situated about two-thirds of the way out from the galaxy’s center, is similarly difficult. Clouds of dust permeate the Milky Way, blocking our view of the galaxy’s stars. Today, researchers have a suitable map of our galaxy’s spiral structure, but, like early explorers charting new territory, they continue to patiently and meticulously fill in the blanks.


Recently, researchers have turned to a new mapping method that takes advantage of data from NASA’s Wide-field Infrared Survey Explorer, or WISE. Using WISE, the research team has discovered more than 400 dust-shrouded nurseries of stars, which trace the shape of our galaxy’s spiral arms. Seven of these “embedded star clusters” are described in a new study published online May 20 in the Monthly Notices of the Royal Astronomical Society.

“The sun’s location within the dust-obscured galactic disk is a complicating factor to observe the galactic structure,” said Denilso Camargo, lead author of the paper from the Federal University of Rio Grande do Sul in Brazil.

The results support the four-arm model of our galaxy’s spiral structure. For the last few years, various methods of charting the Milky Way have largely led to a picture of four spiral arms. The arms are where most stars in the galaxy are born. They are stuffed with gas and dust, the ingredients of stars. Two of the arms, called Perseus and Scutum-Centaurus, seem to be more prominent and jam-packed with stars, while the Sagittarius and Outer arms have as much gas as the other two arms but not as many stars.

The new WISE study finds embedded star clusters in the Perseus, Sagittarius, and Outer arms. Data from the Two Micron All Sky Survey (2MASS), a ground-based predecessor of WISE from NASA, the National Science Foundation and the University of Massachusetts, Amherst, helped narrow down the distances to the clusters and pinpoint their location.

Embedded star clusters are a powerful tool for visualizing the whereabouts of spiral arms because the clusters are young, and their stars haven’t yet drifted away and out of the arms. Stars begin their lives in the dense, gas-rich neighborhoods of spiral arms, but they migrate away over time. These embedded star clusters complement other techniques for mapping our galaxy, such as those used by radio telescopes, which detect the dense gas clouds in spiral arms.

“Spiral arms are like traffic jams in that the gas and stars crowd together and move more slowly in the arms. As material passes through the dense spiral arms, it is compressed and this triggers more star formation,” said Camargo.

WISE is ideal for finding the embedded star clusters because its infrared vision can cut through the dust that fills the galaxy and shrouds the clusters. What’s more, WISE scanned the whole sky, so it was able to perform a thorough survey of the shape of our Milky Way. NASA’s Spitzer Space Telescope also uses infrared images to map the Milky Way’s territory. Spitzer looks along specific lines of sight and counts stars. The spiral arms will have the densest star populations.

NASA’s Jet Propulsion Laboratory in Pasadena, California managed and operated WISE for NASA’s Science Mission Directorate in Washington. The spacecraft was put into hibernation mode in 2011, after it scanned the entire sky twice, thereby completing its main objectives. In September 2013, WISE was reactivated, renamed NEOWISE and assigned a new mission to assist NASA’s efforts to identify potentially hazardous near-Earth objects.
Other authors of the study are: Charles Bonatto and Eduardo Bica, also with the Federal University of Rio Grande do Sul.

For more information on WISE, visit: http://www.nasa.gov/wise

Previous research from Camargo’s team found two embedded clusters far outside the plane of our Milky Way, 16,000 light-years away. A feature story about that work is online at: http://www.jpl.nasa.gov/news/news.php?feature=4497


The new WISE study from the Monthly Notices of the Royal Astronomical Society is online at: http://mnras.oxfordjournals.org/content/450/4/4150.full?keytype=ref&ijkey=tjeJAezGAmgdXzc






NASA’s CubeSat Initiative Aids in Testing of Technology for Solar Sails in Space

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May 20, 2015 
RELEASE 15-101

With help from NASA, a small research satellite to test technology for in-space solar propulsion launched into space Wednesday aboard an Atlas V rocket from Cape Canaveral Air Force Station, Florida, as part of the agency’s CubeSat Launch Initiative.

The Atlas V sent the U.S. Air Force’s X-37B space plane on its fourth mission, which also is carrying NASA’s Materials Exposure and Technology Innovation in Space (METIS) investigation that will expose about 100 different materials samples to the space environment for more than 200 days.

 

LightSail team members Alex Diaz and Riki Munakata prepare the spacecraft for a sail deployment test.

Credits: The Planetary Society

The Planetary Society’s LightSail satellite is a technology demonstration for using solar propulsion on CubeSats, a class of research spacecraft called nanosatellites. Using the momentum transferred from solar photons as they strike a large, thin, reflective sail would allow a spacecraft to accelerate continuously using only the sun’s energy. NASA is considering the use of solar sails on future exploration mission secondary payloads, and data from this mission will advance understanding of this form of propulsion.

This first LightSail mission specifically is designed to test the spacecraft’s critical systems, including the deployment sequence for the Mylar solar sail, which measures 32 square meters (344 square feet). The Planetary Society is planning a second, full solar sailing demonstration flight for 2016.

NASA selected LightSail as part of the agency’s CubeSat Launch Initiative, which provides opportunities for small satellites to fly as auxiliary payloads on planned missions. It was assigned to a launch as part of as the 11th installment of the Educational Launch of Nanosatellite (ELaNa) mission.

The upper stage of the Atlas V included the National Reconnaissance Office’s third auxiliary mission to launch CubeSats. The Ultra Lightweight Technology and Research Auxiliary Satellite (ULTRASat) carried 10 CubeSats — including LightSail — from five organizations. It was made possible through agreements between NASA, the Air Force’s Space and Missile Systems Center and the National Reconnaissance Office to work together on CubeSat integration and launch opportunities.

The cube-shaped satellites measure about four inches on each side, have a volume of about one quart and weigh less than three pounds each. LightSail consists of three CubeSats bundled together. Individual CubeSat research projects may address science, exploration, technology development or education. During the next month, the LightSail team will receive data from the satellite in space. As part of its agreement with NASA, the Planetary Society will provide the agency a report on outcomes and scientific findings.

Since its inception in 2010, the CubeSat Launch Initiative has selected 110 CubeSats primarily from educational and government institutions around the United States. NASA will announce the next call for proposals in August 2015.

For more information about ELaNa, visit: http://www.nasa.gov/mission_pages/smallsats/elana/

For more information about LightSail and the Planetary Society, visit: http://sail.planetary.org

For additional information about NASA’s CubeSat Launch Initiative, visit: http://go.nasa.gov/CubeSat_initiative