NASA's LRO Moves Closer to the Lunar Surface

NASA - Lunar Reconnaissance Orbiter (LRO) patch.

May 5, 2015

NASA’s Lunar Reconnaissance Orbiter (LRO) has completed a maneuver that lowered the spacecraft’s orbit to within 20 kilometers (12 miles) above areas near the lunar South Pole, the closest the spacecraft has ever been to the lunar surface.

On Monday, May 4, 2015 flight controllers at NASA’s Goddard Space Flight Center in Greenbelt, Maryland performed two station keeping burns to change LRO’s orbit. The new orbit allows LRO to pass within 20 km (12 miles) of the South Pole and 165 km (103 miles) over the North Pole.

Image above: The image is a visualization of the LRO spacecraft as it passes low over the moon¹s surface near the lunar South Pole. From this vantage point LRO will continue to make detailed measurements of the lunar surface, and now from its lower orbit near the South Pole will make unique observations of selected areas. Image Credits: NASA/GSFC/SVS.

"We're taking LRO closer to the moon than we've ever done before, but the maneuver is similar to all other station keeping maneuvers, so the mission operations team knows exactly what to do,” said Steve Odendahl, LRO mission manager from NASA Goddard. 

To optimize science return, team members made the decision to change the orbit after determining that the new orbit configuration poses no danger to the spacecraft. LRO can operate for many years at this orbit.

The new orbit enables exciting new science and will see improved measurements near the South Pole. Two of the instruments benefit significantly from the orbit change. The return signal from the Lunar Orbiter Laser Altimeter (LOLA) laser shots will become stronger, producing a better signal. LOLA will obtain better measurements of specific regions near the South Pole that have unique illumination conditions. Diviner will be able to see smaller lunar features through the collection of higher resolution data.

“The lunar poles are still places of mystery where the inside of some craters never see direct sunlight and the coldest temperatures in the solar system have been recorded,” said John Keller, LRO project scientist at NASA Goddard. “By lowering the orbit over the South Pole, we are essentially magnifying the sensitivity of the LRO instruments which will help us understand the mechanisms by which water or other volatiles might be trapped there.”

Launched on June 18, 2009, LRO has collected a treasure trove of data with its seven powerful instruments, making an invaluable contribution to our knowledge about the moon. LRO is managed by NASA's Goddard Space Flight Center in Greenbelt, Maryland, for the Science Mission Directorate at NASA Headquarters in Washington.

For more information on LRO visit: http://www.nasa.gov/lro

Image (mentioned), Text, Credits: NASA’s Goddard Space Flight Center/Nancy Neal Jones/Lynn Jenner.

Cheers, Orbiter.ch

Astronomers Set a New Galaxy Distance Record

NASA / ESA - Hubble Space Telescope 25th Anniversary logo.

May 5, 2015

An international team of astronomers, led by Yale University and the University of California scientists, pushed back the cosmic frontier of galaxy exploration to a time when the universe was only 5 percent of its present age of 13.8 billion years. The team discovered an exceptionally luminous galaxy more than 13 billion years in the past and determined its exact distance from Earth using the combined data from NASA’s Hubble and Spitzer space telescopes, and the Keck I 10-meter telescope at the W. M. Keck Observatory in Hawaii. These observations confirmed it to be the most distant galaxy currently measured, setting a new record. The galaxy existed so long ago, it appears to be only about 100 million years old.

Image above: This is a Hubble Space Telescope image of the farthest spectroscopically confirmed galaxy observed to date (inset). It was identified in this Hubble image of a field of galaxies in the CANDELS survey (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey). NASA’s Spitzer Space Telescope also observed the unique galaxy. The W. M. Keck Observatory was used to obtain a spectroscopic redshift (z=7.7), extending the previous redshift record. Measurements of the stretching of light, or redshift, give the most reliable distances to other galaxies. This source is thus currently the most distant confirmed galaxy known, and it appears to also be one of the brightest and most massive sources at that time. The galaxy existed over 13 billion years ago. The near-infrared light image of the galaxy (inset) has been colored blue as suggestive of its young, and hence very blue, stars. The CANDELS field is a combination of visible-light and near-infrared exposures. Image Credits: NASA, ESA, P. Oesch (Yale U.).

The galaxy, EGS-zs8-1, was originally identified based on its particular colors in images from Hubble and Spitzer and is one of the brightest and most massive objects in the early universe. “It has already grown to more than 15 percent of the mass of our own Milky Way today,” said Pascal Oesch, lead author of the study from Yale University, New Haven, Connecticut.  “But it had only 670 million years to do so. The universe was still very young then.” The new distance measurement also enabled the astronomers to determine that EGS-zs8-1 was still forming stars very rapidly, about 80 times faster than our Milky Way galaxy today (which has a star formation rate of one star per year).

Only a handful of galaxies currently have accurate distances measured in this very early universe. “Every confirmation adds another piece to the puzzle of how the first generations of galaxies formed in the early universe,” said Pieter van Dokkum of Yale, second author of the study. “Only the most sensitive telescopes are powerful enough to reach to these large distances.” The discovery was only possible thanks to the relatively new Multi-Object Spectrometer For Infra-Red Exploration (MOSFIRE) instrument on the Keck I telescope, which allows astronomers to efficiently study several galaxies at the same time.

Measuring galaxies at these extreme distances and characterizing their properties is a main goal of astronomers over the next decade. The observations see EGS-zs8-1 at a time when the universe was undergoing very important changes: the hydrogen between galaxies was transitioning from an opaque to a transparent state. “It appears that the young stars in the early galaxies like EGS-zs8-1 were the main drivers for this transition, called reionization,” said study co-author, Rychard Bouwens of the Leiden Observatory, Leiden, Netherlands.

Hubble and the sunrise over Earth

These new Hubble, Spitzer, and Keck observations together also pose new questions. They confirm that massive galaxies already existed early in the history of the universe, but that their physical properties were very different from galaxies seen around us today. Astronomers now have very strong evidence that the peculiar colors of early galaxies seen in the Spitzer images originate from a very rapid formation of massive, young stars, which interacted with the primordial gas in these galaxies.

The new observations underline the very exciting discoveries that NASA’s James Webb Space Telescope will enable when it is launched in 2018. In addition to pushing the cosmic frontier to even earlier cosmic times, the Webb telescope will be able to dissect the infrared galaxy light of EGS-zs8-1 seen with the Spitzer Space Telescope and will provide astronomers with much more detailed insights into its gas properties. “Our current observations indicate that it will be very easy to measure accurate distances to these distant galaxies in the future with the James Webb Space Telescope,” said Garth Illingworth of the University of California Santa Cruz. “The result of Webb’s upcoming measurements will provide a much more complete picture of the formation of galaxies at the cosmic dawn.”

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington.

For images and more information about Hubble, visit: http://www.nasa.gov/hubble and http://www.spacetelescope.org and http://hubblesite.org

Image (mentioned), Video, Text, Credits: NASA/ESA/Goddard Space Flight Center/Rob Gutro.

Greetings, Orbiter.ch

Traffic Around Mars Gets Busy

NASA - Deep Space Network patch.

May 5, 2015

Fast Facts:

- Five active spacecraft are orbiting Mars, an increase of two since last summer

- An enhanced system warns if two orbiters may approach each other too closely

NASA has beefed up a process of traffic monitoring, communication and maneuver planning to ensure that Mars orbiters do not approach each other too closely.

Deep Space Network. Image Credits: NASA/JPL

Last year's addition of two new spacecraft orbiting Mars brought the census of active Mars orbiters to five, the most ever. NASA's Mars Atmosphere and Volatile Evolution (MAVEN) and India's Mars Orbiter Mission joined the 2003 Mars Express from ESA (the European Space Agency) and two from NASA: the 2001 Mars Odyssey and the 2006 Mars Reconnaissance Orbiter (MRO). The newly enhanced collision-avoidance process also tracks the approximate location of NASA's Mars Global Surveyor, a 1997 orbiter that is no longer working.

It's not just the total number that matters, but also the types of orbits missions use for achieving their science goals. MAVEN, which reached Mars on Sept. 21, 2014, studies the upper atmosphere. It flies an elongated orbit, sometimes farther from Mars than NASA's other orbiters and sometimes closer to Mars, so it crosses altitudes occupied by those orbiters. For safety, NASA also monitors positions of ESA's and India's orbiters, which both fly elongated orbits.

Image above: This graphic depicts the relative shapes and distances from Mars for five active orbiter missions plus the planet's two natural satellites. It illustrates the potential for intersections of the spacecraft orbits. Image Credit: NASA/JPL-Caltech.

"Previously, collision avoidance was coordinated between the Odyssey and MRO navigation teams," said Robert Shotwell, Mars Program chief engineer at NASA's Jet Propulsion Laboratory, Pasadena, California. "There was less of a possibility of an issue. MAVEN's highly elliptical orbit, crossing the altitudes of other orbits, changes the probability that someone will need to do a collision-avoidance maneuver. We track all the orbiters much more closely now. There's still a low probability of needing a maneuver, but it's something we need to manage."

ISRO Mars Orbiter Mission. Image Credit: ISRO

Traffic management at Mars is much less complex than in Earth orbit, where more than 1,000 active orbiters plus additional pieces of inactive hardware add to hazards. As Mars exploration intensifies, though, and will continue to do so with future missions, precautions are increasing. The new process was established to manage this growth as new members are added to the Mars orbital community in years to come.

All five active Mars orbiters use the communication and tracking services of NASA's Deep Space Network, which is managed at JPL. This brings trajectory information together, and engineers can run computer projections of future trajectories out to a few weeks ahead for comparisons.

ESA Mars Express. Image Credit: ESA

"It's a monitoring function to anticipate when traffic will get heavy," said Joseph Guinn, manager of JPL's Mission Design and Navigation Section. "When two spacecraft are predicted to come too close to one another, we give people a heads-up in advance so the project teams can start coordinating about whether any maneuvers are needed."

The amount of uncertainty in the predicted location of a Mars orbiter a few days ahead is more than a mile (more than two kilometers). Calculating projections for weeks ahead multiplies the uncertainty to dozens of miles, or kilometers. In most cases when a collision cannot be ruled out from projections two weeks ahead, improved precision in the forecasting as the date gets closer will rule out a collision with no need for avoidance action. Mission teams for the relevant orbiters are notified in advance when projections indicate a collision is possible, even if the possibility will likely disappear in subsequent projections. This situation occurred on New Year's weekend, 2015.

NASA 2001 Mars Odyssey. Image Credits: NASA/JPL-Caltech

On Jan. 3, automated monitoring determined that two weeks later, MAVEN and MRO could come within about two miles (three kilometers) of each other, with large uncertainties remaining in the exact passing distance. Although that was a Saturday, automatic messages went out to the teams operating the orbiters.

"In this case, before the timeline got short enough to need to plan an avoidance maneuver, the uncertainties shrank, and that ruled out the chance of the two spacecraft coming too near each other," Guinn said. This is expected to be the usual pattern, with the advance warning kicking off higher-level monitoring and initial discussions about options.

NASA Mars Reconnaissance Orbiter (MRO): Image Credits: NASA/JPL-Caltech

If preparations for an avoidance maneuver were called for, spacecraft commands would be written, tested and approved for readiness, but such commands would not be sent to a spacecraft unless projections a day or two ahead showed probability of a hazardous conjunction. The amount of uncertainty about each spacecraft's exact location varies, so the proximity considered unsafe also varies. For some situations, a day-ahead projection of two craft coming within about 100 yards (100 meters) of each other could trigger a maneuver.

The new formal collision-avoidance process for Mars is part of NASA's Multi-Mission Automated Deep-Space Conjunction Assessment Process. A side benefit of it is that information about when two orbiters will be near each other -- though safely apart -- could be used for planning coordinated science observations. The pair could look at some part of Mars or its atmosphere from essentially the same point of view simultaneously with complementary instruments.

NASA Mars Global Surveyor. Image Credit: NASA

Odyssey, MRO and MAVEN -- together with NASA's two active Mars rovers, Opportunity and Spirit -- are part of NASA's robotic exploration of Mars that is preparing the way for human-crewed missions there in the 2030s and later, in NASA's Journey to Mars strategy.

NASA's Goddard Space Flight Center manages the MAVEN project for the NASA Science Mission Directorate, Washington. MAVEN's principal investigator is based at the University of Colorado's Laboratory for Atmospheric and Space Physics. JPL, a division of the California Institute of Technology in Pasadena, manages NASA's Mars Exploration Program and the Odyssey and MRO projects for the Science Mission Directorate. Lockheed Martin Space Systems, Denver, built all three NASA Mars orbiters.

For more about NASA's Mars Exploration Program, visit: http://mars.jpl.nasa.gov and http://www.nasa.gov/mars

For more information about NASA Mars Atmosphere and Volatile Evolution (MAVEN), visit: http://www.nasa.gov/mission_pages/maven/main/index.html

For more information about ISRO Mars Orbiter Mission, visit: http://www.isro.gov.in/pslv-c25-mars-orbiter-mission

For more information about ESA Mars Express, visit: http://www.esa.int/Our_Activities/Space_Science/Mars_Express

For more information about NASA 2001 Mars Odyssey, visit: http://mars.nasa.gov/odyssey/

For more information about NASA Mars Reconnaissance Orbiter (MRO), visit: http://mars.nasa.gov/mro/

For more information about NASA Mars Global Surveyor, visit: http://mars.jpl.nasa.gov/mgs/

Images (mentioned), Text, Credits: NASA/JPL/Guy Webster.

Best regards, Orbiter.ch

A milestone towards a higher-energy nuclear physics facility

CERN - European Organization for Nuclear Research logo.

May 4, 2015

CERN's nuclear physics facility ISOLDE will soon be producing radioactive ion beams at higher energies. The purpose of the HIE-ISOLDE (High Intensity and Energy ISOLDE) project, now in the advanced stages of construction at CERN, is to increase the energy and intensity of the ISOLDE beams. The transportation and installation of the first acceleration module on Saturday, 2 May marked an important milestone in the project. Made up of five superconducting accelerating cavities, this sophisticated module required years of development followed by months of assembly in a clean room at CERN. Once connected to the associated infrastructure, it will undergo several weeks of testing before HIE-ISOLDE is commissioned.

Image above: The first HIE-ISOLDE acceleration module was assembled over the last few months in a new clean room.

The unique ISOLDE facility is dedicated to the production of a large variety of radioactive ion beams for many fields of fundamental and applied research. Each year, its beams are used by around fifty experiments studying a wide range of subjects from the properties of atoms and nuclei to biomedical applications, nuclear astrophysics and solid-state physics. ISOLDE, which celebrated its fiftieth anniversary in 2014, has produced around 700 isotopes of more than 70 elements. HIE-ISOLDE will increase the research opportunities further by producing a greater variety of nuclei.

CERN - LHC, instruments for discover the secrets of the matter and the universe

The new acceleration module will allow HIE-ISOLDE to increase ISOLDE’s beam energy from 3 MeV per nucleon to 4.3 MeV per nucleon by the end of 2015. Ultimately, three further modules will be commissioned, bringing the beam energy from 10 to 15 MeV per nucleon and increasing the beam intensity fourfold.

Note:

CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 22 Member States.

Related links:

CERN's nuclear physics facility ISOLDE: http://home.web.cern.ch/about/experiments/isolde

HIE-ISOLDE: http://hie-isolde.web.cern.ch/hie-isolde/

For more information about the European Organization for Nuclear Research (CERN), visit: http://home.web.cern.ch/

Images, Text, Credits: CERN/Corinne Pralavorio.

Cheers, Orbiter.ch

The brains of astronauts threatened by cosmic rays

Space Sciences logo.

May 4, 2015

SPACE: The duration of a mission to Mars would be sufficient for serious symptoms ...

Astronauts of long duration mission are very exposed for serious radiation

Exposure to radiation, such as radiant in the cosmos, which bombard astronauts during long space trips to Mars, for example, damages the central nervous system and causes permanent cognitive impairment, according to experiments on mice.

"This is not good news for astronauts who make a journey of two to three years return to Mars," said Charles Limoli, the University of California at Irvine, lead author of the research published Friday the journal Advances Science.

"Altering cognitive abilities"

"The decline in work capacity, memory deficits and loss of consciousness and difficulty concentrating during flights in space could affect the core activities of the mission," he explains, adding that "these cosmic radiation could impair the cognitive abilities of astronauts throughout their lives. "

Artist's rendering of the Multi-Purpose Crew Vehicle on a deep space mission

For this research the scientists subjected mice to radiation of high energy particles at Brookhaven National Laboratory (New York). They found that these radiations caused an inflammation in the brains of rodents that disrupted the transmission of nerve signals. Scans revealed how the brain of the communications network was affected by reductions in neuron structure.

Symptoms after a few months

Impairments of synapses that connect neurons, combined with other structural changes interfered with the ability of nerve cells to efficiently transmit electrochemical signals, the researchers explain.

These phenomena corresponded to decreased performance of different learning ability assessment tests and memorize. Although such cognitive deficits in astronauts will not manifest for several months, the duration of a mission to Mars would be sufficient for such symptoms appear, according to Dr. Limoli.

Protected by the Earth's magnetosphere

But, he explains, astronauts on the International Space Station (ISS), which stays of six months, are not exposed to as great intensity because they are protected by the Earth's magnetosphere. The orbital outpost moves between 350 and 400 km altitude. The particles forming cosmic rays are remnants of ancient supernovas, giant explosions marking the death of a star.

Earth's magnetosphere

The work of Dr. Limoli are part of the research program of NASA on the effects of prolonged space flight on humans in preparation for future manned missions to Mars. One solution would be that the spacecraft include enhanced protection against cosmic radiation areas including rest areas, the researchers said.

Related link:

Advances Science article http://advances.sciencemag.org/content/1/4/e1400256

Images, Text, Credits: ATS/NASA/Wikimedia/Orbiter.ch Aerospace.

Greetings, Orbiter.ch

Mimas Stares Back

NASA - Cassini Mission to Saturn patch.

May 4, 2015

The great eye of Saturn's moon Mimas, a 130-kilometer-wide (80-mile) impact crater called Herschel, stares out from the battered moon. Several individual ringlets within the F ring are resolved here, and the small moon Atlas is also seen faintly outside the main rings.

Mimas is 397 kilometers (247 miles across); the view shows principally the moon's anti-Saturn hemisphere. Atlas is 32 kilometers (20 miles) across.

The image was taken in visible light with the Cassini spacecraft narrow-angle camera on April 5, 2005, at a distance of approximately 2.1 million kilometers (1.3 million miles) from Mimas and at a Sun-Mimas-spacecraft, or phase, angle of 72 degrees. The image scale is 13 kilometers (8 miles) per pixel.

 NASA / ESA Cassini spacecraft

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo.

For more information about Cassini mission, visit:http://www.nasa.gov/mission_pages/cassini/main/index.html and http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens

Images, Text, Credits: NASA/JPL/Space Science Institute.

Best regards, Orbiter.ch

Bright Filament Eruption

NASA / ESA - SOHO Mission patch.

May 4, 2015

An elongated solar filament that extended almost half the sun's visible hemisphere erupted into space on April 28-29, 2015, in a large burst of bright plasma. Filaments are unstable strands of solar material suspended above the sun by magnetic forces. Solar astronomers around the world had their eyes on this unusually large filament and kept track as it erupted. Both of the coronagraph instruments on the joint ESA/NASA Solar and Heliospheric Observatory, or SOHO, show the coronal mass ejection associated with the eruption.

The top image was taken by SOHO's LASCO C2 coronagraph and the bottom by LASCO C3.

Bright Filament Eruption (May 1, 2015)

LASCO, which stands for Large Angle Spectrometric Coronagraph, is able to take images of the solar corona by blocking the light coming directly from the Sun with an occulter disk, creating an artificial eclipse within the instrument itself. C2 images show the inner solar corona up to 8.4 million kilometers (5.25 million miles) away from the Sun. C3 images have a larger field of view: They encompass 32 diameters of the Sun. To put this in perspective, the diameter of the images is 45 million kilometers (about 30 million miles) at the distance of the Sun, or half of the diameter of the orbit of Mercury. The white circle in the center of the round disk represents the size of the sun, which is being blocked by the telescope in order to see the fainter material around it.


For more information about SOHO mission, visit: http://www.nasa.gov/mission_pages/soho/ and http://soho.esac.esa.int/

Images, Video, Text, Credits: ESA/NASA/SOHO/Holly Zell.

Greetings, Orbiter.ch