Universe’s most energetic phenomena to be studied

HAWC Observatory is going to study the universe's most energetic phenomena, Zee News reports.

Supernovae, neutron star collisions and active galactic nuclei are among the most energetic phenomena in the known universe. These violent explosions produce high-energy gamma rays and cosmic rays, which can easily travel large distances, making it possible to see objects and events far outside our own galaxy.

The High Altitude Water Cherenkov (HAWC) Gamma-Ray Observatory, located 13,500 feet above sea level on the slopes of Mexico's Volcan Sierra Negra, is the newest tool available to visualize these explosive events and learn more about the nature of high-energy radiation.

Construction is now complete on HAWC's 300th and final detector tank, and the observatory will soon begin collecting data at full capacity. This milestone will be marked with an inaugural event at the observatory on March 19-20, 2015.

University of Maryland's Jordan Goodman said that HAWC truly is the only observatory of its kind and will give them a clearer picture than ever before of the high-energy wonders of the universe.

Each of HAWC's detectors is a huge tank containing 50,000 gallons of ultrapure water with four light sensors anchored to the floor. When gamma rays or cosmic rays reach Earth's atmosphere they set off a cascade of charged particles, and when these particles reach the water in HAWC's detectors, they produce a cone-shaped flash of light known as Cherenkov radiation. The effect is much like a sonic boom produced by a supersonic jet, because the particles are travelling slightly faster than the speed of light when they enter the detectors.

The light sensors record each flash of Cherenkov radiation inside the detector tanks. By comparing nanosecond differences in arrival times at each light sensor, scientists can reconstruct the angle of travel for each particle cascade. The intensity of the light indicates the primary particle's energy, and the pattern of detector hits can distinguish between gamma rays and cosmic rays. With 300 detectors spread over an area equivalent to more than three football fields, HAWC is able to "see" these events in relatively high resolution.

From its perch atop the highest accessible peak in Mexico, HAWC will have 15 percent of the sky within its sights at any given time. As the Earth rotates, so too will HAWC's field of vision, meaning that HAWC will see up to two-thirds of the sky every 24 hours. 

article image The Martian frontier could open up with new mission concepts

 new mission concept could bring previously unaccessible Martian landing sites within reach,

 say its creators at the Planetary Science Institute (PSI). This could mean landings in vast canyons,

 on dormant volcanoes or other locations that rovers can't reach.

The concept is called MARSDROP and it would tag along with a bigger, primary Martian mission. The vehicle would be tiny—adding less than 5% to the cost of a major mission—and would provide more landing opportunities for a single Mars shot, PSI added.

To get to the surface, MARSDROP would use an aerodynamic feature called a parawing, which would give it better steering capabilities than traditional parachutes. The design calls for MARSDROP to reach a target within a few tens of meters, should its video navigation work as planned.

“In addition, MARSDROP can help lay the groundwork for future human exploration of Mars by characterizing biohazards like Martian dust and assessing the availability of key resources, such as water from which oxygen and rocket propellant can be made," stated Rebecca Williams, a senior research scientist at PSI who is working on the project.

How MARSDROP would make it to the Martian surface. Image credit: Planetary Science Institute, NASA

While landers have been exploring the surface of Mars for 40 years, scientists are itching to do more. The traditional big missions only happen once every couple of years, at best, and if you lose a landing chance that can set research far back. This has happened several times, such as with NASA's Mars Polar Lander and the European Space Agency's Beagle 2 spacecraft.

Additionally, a big mission requires a big parachute or landing system, which limits the areas in which the lander can be placed on the Martian surface. At the altitude of a Martian volcano, for example, the air is too thin. And in a hilly area, a rover may have trouble getting around or at worst, get stuck.

Small missions are becoming more common in space exploration these days, notably with CubeSats, small 10 cm cubed satellites. Powerful microelectronics and cameras allow these missions to do more than what could have been possible even a decade ago. And with the idea tested in Earth orbit, scientists are itching to bring the small mission idea to other planets.

MARSDROP, if it were to go forward, would only be about 30 centimeters in diameter and weigh one kilogram, which would force instruments to be small and efficient. But in that small space, scientists are proposing to pack on cameras, microscopes and other instruments that could search for signs of organic materials (the building blocks of life) or tell us more about the Martian surface, for example.

Visualization of Valles Marineris on Mars based on Mars Odyssey data. This could be a candidate landing area for MARSDROP. Image credit: NASA/JPL/Arizona State University

The PSI mission (which is not yet fully developed or approved) represents just one of a few novel proposals lately to explore the Red Planet.

NASA's Jet Propulsion Laboratory is proposing a "Mars helicopter" that could act as a scout for rovers, looking for the best areas to explore. JPL said the rovers could triple their potential driving distance every day with the help of a flying companion, since engineers would have more precise information about the terrain.

To better guage the Martian landscape in 3D, JPL and Microsoft are co-developing technology that would transform the Curiosity rover's images into 3D. Called OnSight, this would allow scientists to virtually walk alongside the rover and identify potential mission targets as Curiosity searches for signs of habitability.

For now, though, the planned and (at least mostly) funded landing missions to Mars remain big and robust. NASA has another rover planned called Mars 2020, while the European Space Agency will launch two ExoMars landing missions in 2016 and 2018. The first will be a simple probe to ride with the Trace Gas Orbiter, while the second will be a rover.

Credit: Elizabeth Howell, News Writer

A Grand Extravaganza of New Stars

This dramatic landscape in the southern constellation of Ara (The Altar) is a treasure trove of celestial objects. Star clusters, emission nebulae and active star-forming regions are just some of the riches observed in this region lying some 4000 light-years from Earth. This beautiful new image is the most detailed view of this part of the sky so far, and was taken using the VLT Survey Telescope at ESO’s Paranal Observatory in Chile.

This dramatic landscape in the southern constellation of Ara (The Altar) is a treasure trove of celestial objects. Star clusters, emission nebulae and active star-forming regions are just some of the riches observed in this region lying some 4000 light-years from Earth. This beautiful new image is the most detailed view of this part of the sky so far, and was taken using the VLT Survey Telescope at ESO’s Paranal Observatory in Chile.

At the centre of the image is the open star cluster NGC 6193, containing around thirty bright stars and forming the heart of the Ara OB1 association. The two brightest stars are very hot giant stars. Together, they provide the main source of illumination for the nearby emission nebula, the Rim Nebula, or NGC 6188, which is visible to the right of the cluster.

full details - http://www.eso.org/public/news/eso1510/

Millions of stars forming in a nearby Galaxy.

The blue background is a Hubble Space Telescope image of galaxy NGC 5253; the white spots are young star clusters. Superimposed is the gas (fuzzy red to yellow) as seen by the Submillimeter Array. The brightest part of the image is Cloud D.

Within a super-nebula in a dwarf galaxy known as NGC 5253, in the constellation Centaurus, Star Cluster is buried. The cluster has one billion times the luminosity of our sun, but is invisible in ordinary light, hidden by its own hot gases.

More than a million young stars are forming in a hot, dusty cloud of molecular gases in a tiny galaxy near our own, an international team of astronomers has discovered.

“We are stardust, and this cluster is a factory of stars and soot,” said Jean Turner, a professor of physics and astronomy in the UCLA College and lead author of the research, which is published March 19 in the journal Nature. “We are seeing the dust that the stars have created. Normally when we look at a star cluster, the stars long ago dispersed all their gas and dust, but in this cluster, we see the dust.

“I’ve been searching for the gas cloud that is forming the supernebula and its star cluster for years,” she said. “Now we have detected it.”

The amount of dust surrounding the stars is extraordinary — approximately 15,000 times the mass of our sun in elements such as carbon and oxygen.

“We were stunned,” said Turner, who is chair of the department of physics and astronomy.

The Cluster is no older than 3 million years old, which in Astronomical Units is very young and is likely to live more than a billion year.

The Milky Way has not formed gigantic star clusters for billions of years, Turner said. It is still forming new stars, but not in nearly such large numbers, she said. Some astronomers had believed that such giant star clusters could form only in the early universe.

The Milky Way has gas clouds, but nothing comparable to this galaxy’s Cloud D — see the bright white area in the photo — which houses the enormous star cluster enshrouded in thick gas and dust, Turner said.

How much of a gas cloud gets turned into stars varies in different parts of the universe. In the Milky Way, the rate for gas clouds the size of Cloud D is less than 5 percent. In Cloud D, the rate is at least 10 times higher, and perhaps much more.

Turner and her colleagues conducted the research with the Submillimeter Array, a joint project of the Smithsonian Astrophysical Observatory and the Academia Sinica Institute of Astronomy and Astrophysics, on Hawaii’s Mauna Kea.

NGC 5253 has hundreds of large star clusters, including at least several that are young, the astronomers report. The most spectacular is found within Cloud D.

“We’re catching this cluster at a special time,” Turner said. “With a cluster this large, we would expect several thousand stars that would have become supernovae and exploded by now. We found no evidence of a supernova yet.”

The cluster contains more than 7,000 massive “O” stars — the most luminous of all known stars, each a million times brighter than our sun.

NGC 5253 has approximately nine times as much dark matter as visible matter — a much higher rate than the inner parts of the Milky Way, Turner said.

In coming years, the cloud could be destroyed by stars that become supernovae, Turner said, “which would spin all of the gas and elements created by the stars into interstellar space.”

Co-authors of the research include S. Michelle Consiglio, a UCLA graduate student of Turner’s; David Meier, a former UCLA graduate student who is now at the New Mexico Institute of Mining and Technology; Sara Beck, astronomy professor at Israel’s University of Tel Aviv School of Physics and Astronomy; Paul Ho of Taiwan’s Academia Sinica Astronomy and Astrophysics; and Jun-Hui Zhao of the Harvard-Smithsonian Center for Astrophysics.

Turner and colleagues first detected the star cluster’s radio emission in 1996. They will continue to study the galaxy using the Atacama Large Millimeter/submillimeter Array in Chile.

PC:Hubble Telescope

PC: Hubble Telescope

Mars One finalist says the project may be doomed

The much-hyped Mars One project may crash and burn before it even gets off the ground. Joseph Roche, an assistant professor at Trinity College Dublin and one of Mars One’s 100 finalists, recently spoke out on the project, and it’s starting to sound more like a pyramid scheme than a space exploration endeavor.

Mars One: revelations and implications

While Mars One originally led the public to believe that candidates were undergoing a strenuous vetting and interview process, it turns out that candidates have actually been ranked on a “points” system that has more to do with how much money they raise for the project than anything else.

Mars enthusiasts may have to turn to someone besides eccentric billionaires to make their space exploration dreams come true.

Roche, who holds PhDs in physics and astrophysics, said he had originally signed up for the project out of curiosity, but he found himself increasingly worried about all the media coverage the project was receiving. One of his most striking revelations involves a press guide provided to the finalists in February, which asked that they “donate 75% of profits” from any speaking engagements to Mars One. According to Roche, the “Top 10 hopefuls” featured in The Guardian in February were simply the candidates who had brought in the most money for Mars One.

Additionally, Roche said that he was never made subject to any rigorous testing or psychological evaluations. In fact, the entirety of his interactions with Mars One staff boiled down to one ten-minute Skype interview with Dr. Norbert Kraft, the project’s chief medical officer, during which he was quizzed on material that had been given to him a month before.

Elmo Keep, who spoke with Roche and who has reported extensively on Mars One in the past, summarized Mars One’s current situation beautifully:

So, here are the facts as we understand them: Mars One has almost no money. Mars One has no contracts with private aerospace suppliers who are building technology for future deep-space missions. Mars One has no TV production partner. Mars One has no publicly known investment partnerships with major brands. Mars One has no plans for a training facility where its candidates would prepare themselves. Mars One’s candidates have been vetted by a single person, in a 10-minute Skype interview.

While Roche said coming forward was difficult, he felt he had too since he feared that “people (would) lose faith in NASA and possibly even in scientists…If I was somehow linked to something that could do damage to the public perception of science, that is my nightmare scenario.”

In a world in which the US Senate’s Chairman of the Committee on Environment and Public Works throws a snowball on the Senate floor to supposedly disprove climate change, Roche’s concerns are frighteningly resonant.

Mars One candidates are just a few million ribbon-cutting ceremonies away from landing in the shadow of Olympus Mons.