Tag: NASA

WASHINGTON (TIP): Astronomers using data from Nasa’s Fermi Gamma-ray Space Telescope have detected hints of periodic changes in the brightness of a so-called “active” galaxy, whose emissions are powered by a supersized black hole.

If confirmed, the discovery would mark the first years-long cyclic gamma-ray emission ever detected from any galaxy, providing new insights into physical processes near the black hole.

“Looking at many years of data from Fermi’s Large Area Telescope (LAT), we picked up indications of a roughly two-year-long variation of gamma rays from a galaxy known as PG 1553+113,” said Stefano Ciprini, who coordinates the Fermi team at the Italian Space Agency’s Science Data Center (ASDC) in Rome.

“This signal is subtle and has been seen over less than four cycles, so while this is tantalising we need more observations,” he added.

Supermassive black holes lie at the hearts of most large galaxies, including our own Milky Way.

In about one percent of these galaxies, the monster black hole radiates billions of times as much energy as the sun, emission that can vary unpredictably on timescales ranging from minutes to years.

Astronomers refer to these as “active” galaxies.

More than half of the gamma-ray sources seen by Fermi’s LAT are active galaxies called blazars.

If the gamma-ray cycle of PG 1553+113 is in fact real, the scientists predict it will peak again in 2017 and 2019, well within Fermi’s expected operational lifetime.

PG 1553+113 lies in the direction of the constellation Serpens, and its light takes about five billion years to reach Earth. Nasa’s Fermi Gamma-ray Space Telescope was launched in June 2008.

Nasa’s New Horizons spacecraft has returned the best colour and the highest resolution images yet of Pluto’s largest moon, Charon, which show a surprisingly complex and violent history.

The image combines blue, red and infrared images taken by the spacecraft’s Ralph/Multispectral Visual Imaging Camera (MVIC); the colours are processed to best highlight the variation of surface properties across Charon.

Charon’s colour palette is not as diverse as Pluto’s; most striking is the reddish north polar region, informally named Mordor Macula, Nasa said.

Charon is 1,214 kilometres across. The image resolves details as small as 2.9 kilometers.

At half the diameter of Pluto, Charon is the largest satellite relative to its planet in the solar system.

Charon’s cratered uplands at the top are broken by series of canyons, and replaced on the bottom by the rolling plains of the informally named Vulcan Planum.

The scene covers Charon’s width of 1,214 kilometres and resolves details as small as 0.8 kilometres.

Another image shows the details of a belt of fractures and canyons just north of the moon’s equator.

This great canyon system stretches more than 1,600 kilometres across the entire face of Charon and likely around onto Charon’s far side.

WASHINGTON (TIP): Researchers at Nasa have successfully tested an umbrella-like heat shield made of carbon fabric that could protect future Mars exploration vehicles from extreme heat when entering the red planet’s atmosphere.

As Nasa missions to Mars progress with science and complex human exploration missions, spacecrafts will require larger heat shields to protect against the extreme heat of entering a planet’s atmosphere and decelerating at a safe altitude in the thin Martian atmosphere, the US space agency said.

Today’s rockets have limited space to accommodate spacecraft and their heat shields.

However, engineers at Nasa’s Ames Research Centre may have a solution —Adaptive Deployable Entry and Placement Technology (ADEPT).

ADEPT is a mechanically-deployable heat shield concept using carbon fabric— a flexible heat shield that expands to “open” like an umbrella.

Ames’ engineers have successfully completed heating simulation testing of an ADEPT model under conditions akin to entering the Martian atmosphere.

The test used a blast of hot air from a 21 inches diameter nozzle to simulate a bow shock wave in front of a 2 m wide ADEPT shield, which was attached to a water—cooled support arm.

During the tests, temperatures on the shield reached 1,700 degrees Celsius while bluish streaks streamed away as a special resin—infused protective coating ablated from the stitching.

Extensive instrumentation and imaging products from the test will be used to validate how materials respond to the testing conditions, and thermo—structural design codes.

The testing approach demonstrated with this test will enable future, more extensive testing of the ADEPT configuration — towards possible future use of the system on missions bigger than anything NASA’s ever flown.

The ADEPT project is led by Nasa’s Ames Research Centre, with contributions from multiple other Nasa centres.

WASHINGTON (TIP): Two US airlines will soon begin testing a new NASA-developed software that is designed to help air carriers save time, cut fuel consumption and carbon emissions.

During the next three years, Virgin America and Alaska Airlines will use the Traffic Aware Planner (TAP) application to make “traffic aware strategic aircrew requests” (TASAR), the US space agency said in a statement.

TAP connects directly to the aircraft avionics information hub on the aircraft.

“It reads the current position and altitude of the aircraft, its flight route and other real-time information that defines the plane’s current situation and active flight plan,” explained David Wing, TASAR project lead at NASA’s Langley Research Center in Hampton, Virginia.

Then, it automatically looks for a variety of route and/or altitude changes that could save fuel or flight time and displays those solutions directly to the flight crew.

TAP also scans the signals of nearby air traffic to avoid potential conflicts in any proposed flight path changes, making it easier for air traffic controllers to approve a pilot’s route change request. For airlines with internet connectivity in the cockpit, TAP also can access information –such as real-time weather conditions, wind forecast updates and restricted airspace status — to further increase flight efficiency.

The software is loaded onto a tablet computer, which many airline pilots already use for charts and flight calculations. Even four minutes of flight time shaved off of each leg of a trip made by an airline could result in massive fuel and time savings, according to researchers.

The software provided similar results in flight tests. A second round of flight tests was recently completed to ensure readiness for operational use by partner airlines.

“We are excited to partner with NASA to test this new technology that has the potential to help reduce fuel consumption and carbon emissions and save our guests time in the air,” commented Steve Forte, Virgin America’s chief operating officer in Burlingame, California.

WASHINGTON (TIP): NASA’s Dawn spacecraft has shown the brightest spots on the dwarf planet Ceres that are gleaming with mystery.

The closest-yet view of Occator crater, with a resolution of 450 feet per pixel, on its surface gives scientists a deeper perspective on these very unusual features.

The new up-close view reveals better-defined shapes of the brightest, central spot and features on the crater floor.

“Dawn has transformed what was so recently a few bright dots into a complex and beautiful, gleaming landscape,” said Marc Rayman, Dawn’s chief engineer and mission director from NASA’s Jet Propulsion Laboratory in California.

Dawn is the first mission to visit a dwarf planet, and the first to orbit two distinct solar system targets.

“Soon, the scientific analysis will reveal the geological and chemical nature of this mysterious and mesmerising extraterrestrial scenery,” he said in a statement.

Because these spots are so much brighter than the rest of Ceres’ surface, the Dawn team combined two different images into a single composite view — one properly exposed for the bright spots, and one for the surrounding surface.

Scientists also have produced animations that provide a virtual fly-around of the crater, including a colourful topographic map.

Dawn scientists note the rim of Occator crater is almost vertical in some places, where it rises steeply for nearly two km. The spacecraft has already completed two 11-day cycles of mapping the surface of Ceres from its current altitude.

Dawn will map all of Ceres six times over the next two months.

WASHINGTON (TIP): NASA’s Dawn spacecraft has delivered the closest-yet views of the dwarf planet called Ceres that show the small world’s features in unprecedented detail.

The new images show Ceres’ tall, conical mountain, crater formation features and narrow, braided fractures.

“Dawn’s view is now three times as sharp as in its previous mapping orbit, revealing exciting new details of this intriguing dwarf planet,” said Marc Rayman, Dawn’s chief engineer and mission director at NASA’s Jet Propulsion Laboratory in California.

Engineers and scientists will now refine their measurements of Ceres’ gravity field which will help mission planners in designing Dawn’s next orbit — its lowest — as well as the journey to get there.

In late October, Dawn will begin spiraling toward this final orbit, which will be at an altitude of 375 km.

At its current orbital altitude of 1,470 km, Dawn takes 11 days to capture and return images of Ceres’ whole surface.

Each 11-day cycle consists of 14 orbits.

Over the next two months, the spacecraft will map the entirety of Ceres six times.

The spacecraft is using its framing camera to extensively map the surface, enabling 3-D modeling.

Every image from this orbit has a resolution of 450 feet per pixel, and covers less than one percent of the surface of Ceres.

At the same time, Dawn’s visible and infrared mapping spectrometer is collecting data that will give scientists a better understanding of the minerals found on Ceres’ surface.

Dawn is the first mission to visit a dwarf planet, and the first to orbit two distinct solar system targets.

It orbited protoplanet Vesta for 14 months in 2011 and 2012 and arrived at Ceres on March 6, 2015.

WASHINGTON (TIP): With its biggest orbit manoeuvre since 2006, NASA’s Mars Reconnaissance Orbiter (MRO) is preparing for the arrival of NASA’s next Mars lander called InSight next year.

The Mars orbiter will be engaged in a 77-second firing of six intermediate-size thrusters that will adjust the orbit timing of the veteran spacecraft.

The move will put the orbiter in position to receive radio transmissions from InSight as the newcomer descends through the Martian atmosphere and touches down on September 28 next year, the US space agency said in a statement.

These six rocket engines, which were used for trajectory corrections during the spacecraft’s flight from Earth to Mars, can each produce about five pounds of thrust.

“Without making this orbit change manoeuvre, Mars Reconnaissance Orbiter would be unable to hear from InSight during the landing, but this will put us in the right place at the right time,” said MRO project manager Dan Johnston of NASA’s Jet Propulsion Laboratory, Pasadena, California.

The orbiter will record InSight’s transmissions for later playback to Earth as a record of each event during the critical minutes of InSight’s arrival at Mars.

This is the same exercise that MRO did for the landings of NASA’s Curiosity Mars rover three years ago and NASA’s Phoenix Mars lander in 2008.

InSight will examine the deep interior of Mars for clues about the formation and early evolution of all rocky planets, including Earth.

After the InSight landing, the scientists will prepare MRO to perform a pair of even larger manoeuvres in October 2016 and April 2017 — each using the six intermediate-size thrusters longer than three minutes.

HOUSTON (TIP): NASA said Thursday, July 23, that its Kepler spacecraft has spotted “Earth’s bigger, older cousin”: the first nearly Earth-size planet to be found in the habitable zone of a star similar to our own.

Though NASA can’t say for sure whether the planet is rocky like ours or has water and air, it’s the closest match yet found.

“Today, Earth is a little less lonely,” Kepler researcher Jon Jenkins said.

The planet, Kepler-452b, is about 1,400 light-years from Earth in the constellation Cygnus. It’s about 60% bigger than Earth, NASA says, and is located in its star’s habitable zone — the region where life-sustaining liquid water is possible on the surface of a planet.

A visitor there would experience gravity about twice that of Earth’s, and planetary scientists say the odds of it having a rocky surface are “better than even.”

While it’s a bit farther from its star than Earth is from the sun, its star is brighter, so the planet gets about the same amount of energy from its star as Earth does from the sun. And that sunlight would be very similar to Earth’s, Jenkins said.

The planet “almost certainly has an atmosphere,” Jenkins said, although scientists can’t say what it’s made of. But if the assumptions of planetary geologists are correct, he said, Kepler-452b’s atmosphere would probably be thicker than Earth’s, and it would have active volcanoes.

It takes 385 days for the planet to orbit its star, very similar to Earth’s 365-day year, NASA said. And because it’s spent so long orbiting in this zone — 6 billion years — it’s had plenty of time to brew life, Jenkins said.

“That’s substantial opportunity for life to arise, should all the necessary ingredients and conditions for life exist on this planet,” he said in a statement.

Before the discovery of this planet, one called Kepler-186f was considered the most Earthlike, according to NASA. That planet, no more than a 10th bigger than Earth, is about 500 light-years away from us. But it gets only about a third of the energy from its star as Earth does from the sun, and noon there would look similar to the evening sky here, NASA says.

The $600 million Kepler mission launched in 2009 with a goal to survey a portion of the Milky Way for habitable planets.

From a vantage point 64 million miles from Earth, it scans the light from distant stars, looking for almost imperceptible drops in a star’s brightness, suggesting a planet has passed in front of it.

It has discovered more than 1,000 planets. Twelve of those, including Kepler-425b, have been less than twice the size of Earth and in the habitable zones of the stars they orbit.

Missions are being readied to move scientists closer to the goal of finding yet more planets and cataloging their atmospheres and other characteristics.

In 2017, NASA plans to launch a planet-hunting satellite called TESS that will be able to provide scientists with more detail on the size, mass and atmospheres of planets circling distant stars.

The next year, the James Webb Space Telescope will go up. That platform, NASA says, will provide astonishing insights into other worlds, including their color, seasonal differences, weather and even the potential presence of vegetation.

WASHINGTON (TIP): New images of Ceres from Nasa’s Dawn spacecraft has provided more visible images of mysterious bright spots and also revealed a pyramid-shaped peak towering over a relatively flat landscape.

Dawn has been studying the dwarf planet Ceres, the largest object in the main asteroid belt between Mars and Jupiter, in detail from its second mapping orbit, which is 4,400 km above Ceres.

A new view of its intriguing bright spots, located in a crater 90 km across, shows even more small spots in the crater than were previously visible, the US space agency said.

At least eight spots can be seen next to the largest bright area, which scientists think is approximately 9km wide.

Although ice and salt are leading candidates that could explain these spots, scientists are considering other options, too.

“The surface of Ceres has revealed many interesting and unique features. For example, icy moons in the outer solar system have craters with central pits but on Ceres central pits in large craters are much more common,” said Carol Raymond, deputy principal examiner for the Dawn mission, based at Nasa’s Jet Propulsion Laboratory in Pasadena, California.

“These and other features will allow us to understand the inner structure of Ceres that we cannot sense directly.”

Dawn’s visible and infrared mapping spectrometer allows scientists to identify specific minerals present on Ceres by looking at how light is reflected.

Each mineral reflects the range of visible and infrared-light wavelengths in a unique way and this signature helps scientists determine the components of Ceres.

So, as the spacecraft continues to send back more images and data, scientists will learn more about the mystery bright spots, Nasa said.

In addition to the bright spots, the latest images also show a mountain with steep slopes protruding from a relatively smooth area of the dwarf planet’s surface.

The structure rises about five km above the surface.

Dawn is the first mission to visit a dwarf planet and the first to orbit two distinct targets in our solar system.

It arrived at Ceres on March 6, 2015 and will remain in its current altitude until June 30.

WASHINGTON (TIP): NASA’s Hubble space telescope has provided the first glimpse of Pluto’s moons that wobble unpredictably, tumbling in absolute chaos.

It means if you lived on one of Pluto’s moons, you might have a hard time determining when, or from which direction, the Sun will rise each day.

“Hubble has provided a new view of Pluto and its moons revealing a cosmic dance with a chaotic rhythm,” said John Grunsfeld, associate administrator of NASA’s Science Mission Directorate in Washington, DC.

When the New Horizons spacecraft flies through the Pluto system in July, we will get a chance to see what these moons look like up close and personal, he added in a NASA statement.

Comprehensive analysis of the data shows that two of Pluto’s moons, Nix and Hydra, wobble unpredictably.

The moons wobble because they are embedded in a gravitational field that shifts constantly.

This shift is created by the double planet system of Pluto and Charon as they whirl about each other.

Pluto and Charon are called a double planet because they share a common centre of gravity located in the space between the bodies.

Their variable gravitational field sends the smaller moons tumbling erratically.

The effect is strengthened by the football-like, rather than spherical, shape of the moons.

Scientists believe it is likely that Pluto’s other two moons, Kerberos and Styx, are in a similar situation.

The astonishing results were found by Mark Showalter of the SETI Institute in Mountain View, California and Doug Hamilton of the University of Maryland at College Park.

They also found three of Pluto’s moons are presently locked together in resonance, meaning there is a precise ratio for their orbital periods.

“We are learning chaos may be a common trait of binary systems,” Hamilton said. “It might even have consequences for life on planets if found in such systems.”

“Pluto will continue to surprise us when New Horizons flies past it in July,” Showalter said.

The New Horizons spacecraft may help settle the oddities uncovered by Hubble. The new findings will also provide important new constraints on the sequence of events that led to the formation of the system.

WASHINGTON (TIP): The mysterious dark material coating some geological features of Jupiter’s moon Europa is likely sea salt from a subsurface ocean, discoloured by exposure to radiation, NASA scientists have found.

Presence of sea salt on Europa’s surface suggests the ocean is interacting with its rocky seafloor – an important consideration in determining whether the icy moon could support life.

“We have many questions about Europa, the most important and most difficult to answer being is there life?Research like this is important because it focuses on questions we can definitively answer, like whether or not Europa is inhabitable,” said Curt Niebur, Outer Planets Programme scientist at NASA Headquarters here.

“Once we have those answers, we can tackle the bigger question about life in the ocean beneath Europa’s ice shell,” said Niebur.

For more than a decade, scientists have wondered about the nature of the dark material that coats long, linear fractures and other relatively young geological features on Europa’s surface.

Its association with young terrains suggests the material has erupted from within Europa, but with limited data available, the material’s chemical composition has remained elusive.

“If it’s just salt from the ocean below, that would be a simple and elegant solution for what the dark, mysterious material is,” said research lead Kevin Hand, a planetary scientist at NASA’s Jet Propulsion Laboratory in California.

One certainty is that Europa is bathed in radiation created by Jupiter’s powerful magnetic field. Electrons and ions slam into the moon’s surface with the intensity of a particle accelerator.

Theories proposed to explain the nature of the dark material include this radiation as a likely part of the process that creates it.

Previous studies using data from NASA’s Galileo spacecraft, and various telescopes, attributed the discolourations on Europa’s surface to compounds containing sulphur and magnesium.

While radiation-processed sulphur accounts for some of the colours on Europa, the new experiments reveal that irradiated salts could explain the colour within the youngest regions of the moon’s surface.

To identify the dark material, Hand and his co-author Robert Carlson, also at JPL, created a simulated patch of Europa’s surface in a laboratory test apparatus for testing possible candidate substances.

CAPE CANAVERAL, Florida (TIP): Nasa’s pioneering Messenger spacecraft ended its four-year study of the planet Mercury on Thursday by crashing into the planet’s surface, scientists said.

Flight controllers at the Johns Hopkins University Applied Physics Laboratory in Maryland earlier estimated that Messenger, traveling at more than 8,700mph (14,000kph), would hit the ground near Mercury’s north pole at 3.26pm EDT (1926 GMT).

Messenger, with no more fuel to maneuver, fought the downward push of the sun’s gravity until it impacted the planet’s surface. It likely gouged a 52-foot-wide (16 meter) crater into Mercury’s scarred face.

During its final weeks in orbit, Messenger relayed more details about the innermost planet of the solar system, which turns out to have patches of ice inside some of its craters, despite its sizzling location more than twice as close to the sun as Earth.

“We’ve been concentrating on getting as much of the data down on the ground,” lead researcher Sean Solomon, with Columbia University in New York, wrote in an email. “We will have years to think about the meaning of the measurements.”

Messenger (Mercury Surface, Space ENvironment, GEochemistry, and Ranging craft) made the first close-up studies of Mercury since Nasa’s Mariner 10 spacecraft flew by the planet three times in the mid-1970s. It arrived at Mercury in 2011 after a circuitous six-year journey.

During its 4,104 orbits of Mercury, Messenger made surprising detections of potassium, sulfur and other volatiles on the planet’s surface that presumably should have evaporated due to the planet’s high temperature. Mercury’s average surface temperature is 332 degrees Fahrenheit (167 degrees Celsius), with daytime highs of 801 degrees Fahrenheit (427 degrees Celsius.)

Messenger also confirmed the existence of ices and other materials, possibly even carbon-based organics, on the floors of craters where sunlight never shines. During its final days, Messenger attempted to peer directly down into targeted craters, Solomon said.It also found evidence of past volcanic activity and signs the dense and shrinking planet has a liquid-iron core.

WASHINGTON (TIP): Nasa scientists have joined the hunt for extraterrestrial life and will adapt a global climate model to simulate conditions on potentially habitable exoplanets.

The effort by Nasa Goddard Institute for Space Studies (GISS) is part of a broader push to identify Earth-like worlds. Nasa’s space-based Kepler telescope has pinpointed more than 1,000 alien planets by observing the brief interruption of starlight that signals a planet passing in front of its parent star.

At least five of these planets are similar in size to Earth and located in the ‘habitable zone’, where liquid water could persist.

“We have to start thinking about these things as more than planetary objects,” said Anthony Del Genio, a climate modeller who is leading the GISS effort. “All of a sudden, this has become a topic not just for astronomers, but for planetary scientists and now climate scientists,” Del Genio said.

Del Genio’s group is one of around 16 – ranging from Earth and planetary scientists to solar physicists and astrophysicists – that are participating in Nasa’s new Nexus for Exoplanet System Science (NExSS) programme, ‘Nature.com’ reported.

“We are bringing together a bunch of different disciplines, and they all look at the formation and functioning of planets in different ways,” said Mary Voytek, who directs Nasa’s astrobiology programme and organised NExSS.

NExSS will expand the network of researchers collaborating on exoplanets, she said.

That should help scientists to make sense of existing data and observations from the James Webb Space Telescope and the Transiting Exoplanet Survey Satellite, which are both scheduled for launch in 2018. It could also help Nasa develop missions to hunt for exoplanets in the 2020s and beyond.

At GISS, Del Genio’s team has started repurposing the institution’s workhorse Earth-system climate model.

The researchers are trying to locate simple parameters that are fixed for Earth, such as 24-hour days and 365-day orbits, in order to create an exoplanet model that can be adjusted for different planetary systems.

Initial simulations will focus on the Earth’s ancient past and the evolution of Venus and Mars. Although neither can support life today, each may have had liquid surface water at some time.

The team’s ultimate goal is to explore the concept of a habitable zone by mixing and matching some of the key factors that determine whether a planet can support life.

By feeding these parameters into the exoplanet model, the group will create a database of ‘hypothetical atmospheres’ with spectra that could be visible to astronomers.