- Scientists Predict Earth-like Planets Around Most Stars
- Russian Satellite Comes Back to Life After Unknown Glitch
- New Horizons Spacecraft Returns New Images of Pluto
- Progress Toward the Understanding of the Galactic Structure
- Lunar Reconnaissance Orbiter Discovers Lunar Hydrogen More Abundant on Moon's Pole-Facing Slopes
- Estonia Becomes ESA Member State
- ESA's Rosetta Spacecraft Swoops in for a Close Encounter
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Posted: 05 Feb 2015 04:41 AM PST
Planetary scientists have calculated that there are hundreds of billions of Earth-like planets in our galaxy which might support life. The new research, led by PhD student Tim Bovaird and Associate Professor Charley Lineweaver from The Australian National University (ANU), made the finding by applying a 200 year old idea to the thousands of exo-planets discovered by the Kepler space telescope. They found the standard star has about two planets in the so-called goldilocks zone, the distance from the star where liquid water, crucial for life, can exist.
“The ingredients for life are plentiful, and we now know that habitable environments are plentiful,” said Associate Professor Lineweaver, from the ANU Research School of Astronomy and Astrophysics and the Research School of Earth Sciences. “However, the universe is not teeming with aliens with human-like intelligence that can build radio telescopes and space ships. Otherwise we would have seen or heard from them. “It could be that there is some other bottleneck for the emergence of life that we haven’t worked out yet. Or intelligent civilisations evolve, but then self-destruct.” The Kepler space telescope is biased towards seeing planets very close to their stars, that are too hot for liquid water, but the team extrapolated from Kepler’s results using the theory that was used to predict the existence of Uranus. “We used the Titius-Bode relation and Kepler data to predict the positions of planets that Kepler is unable to see,” Associate Professor Lineweaver said. The research is published in Monthly Notices of the Royal Astronomical Society. It is available online. Credit: anu.edu.au  | ||
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Posted: 04 Feb 2015 11:41 PM PST
Russia’s space satellite Express-AM33 has come back to life, the press-service of the Satellite Communications company told TASS. "At 15:00 on February 4 the Satellite Communications state enterprise and the Reshetnev Company "Information Satellite Systems" managed to fully restore the operation of the Express-AM33 satellite and resume communication and broadcasting services provided on its basis," the press-service said.
Earlier, a source in the space rocket industry told TASS an unidentified glitch had upset the satellite’s operation.
Express-AM33 was put in orbit in January 2008 and went operational in April 2008.
According to information available from open sources, the satellite is a joint product of the Reshetnev Company "Information Satellite Systems" and Thales Alenia Space, built under a contract with the federal state unitarian enterprise Satellite Communications. The Express-AM33 spacecraft is equipped with with up-to-date antenna systems, that provide high-quality communications and uniform coverage.
Express-AM33 provides digital TV broadcasting, telephony, video conferencing, data transmission and Internet access services. It covers a vast territory of Russia, Kazakhstan, northern regions of Central Asia, Mongolia and China.
Credit: TASS
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Posted: 04 Feb 2015 03:59 PM PST
Pluto discoverer Clyde Tombaugh could only dream of a spacecraft flying past the small planet he spotted on the edges of the solar system in 1930. Yet the newest views of Pluto from NASA's approaching New Horizons probe – released today, on the late American astronomer's birthday – hint at just how close that dream is to coming true. Tombaugh, who died in 1997, was born on Feb. 4, 1906. "This is our birthday tribute to Professor Tombaugh and the Tombaugh family, in honor of his discovery and life achievements — which truly became a harbinger of 21st century planetary astronomy," said New Horizons Principal Investigator Alan Stern, from the Southwest Research Institute, Boulder, Colorado. "These images of Pluto, clearly brighter and closer than those New Horizons took last July from twice as far away, represent our first steps at turning the pinpoint of light Clyde saw in the telescopes at Lowell Observatory 85 years ago, into a planet before the eyes of the world this summer."
The new images, taken with New Horizons' telescopic Long-Range Reconnaissance Imager (LORRI) on Jan. 25 and Jan. 27, were the first acquired during the spacecraft's 2015 approach to the Pluto system, which culminates with a close flyby of Pluto and its system of moons on July 14. New Horizons was more than 126 million miles (203 million kilometers) away from Pluto when it began taking the photos, which show Pluto and largest moon, Charon.
"Pluto is finally becoming more than just a pinpoint of light," said Hal Weaver, New Horizons project scientist at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland. "LORRI has now resolved Pluto, and the dwarf planet will continue to grow larger and larger in the images as New Horizons spacecraft hurtles toward its targets. The new LORRI images also demonstrate that the camera's performance is unchanged since it was launched more than nine years ago."
Over the next few months, LORRI will take hundreds of pictures of Pluto against star fields to refine the team's estimates of New Horizons' distance to Pluto. As in these first images, the Pluto system will resemble little more than bright dots in the camera's view until late spring, but mission navigators will use these images to design course-correcting engine maneuvers that precisely aim New Horizons on approach. The first such maneuver based on these "optical navigation" images, or "OpNavs," is scheduled for March 10.
Closing in on Pluto at about 31,000 miles per hour, New Horizons has already covered more than 3 billion miles since launch on Jan. 19, 2006. Its epic journey has taken it past each planet's orbit from Mars to Neptune in record time, and it is now in the first stage of an encounter with Pluto that includes long-distance imaging as well as dust, energetic particle and solar wind measurements to characterize the space environment near Pluto.
"My dad would be thrilled with New Horizons," said Annette Tombaugh, Clyde Tombaugh's daughter, of Las Cruces, New Mexico. "To actually see the planet that he had discovered and find out more about it, to get to see the moons of Pluto ... he would have been astounded. I'm sure it would have meant so much to him if he were still alive today."
“The U.S. has led the exploration of the planets and continues to do so with New Horizons,” said Curt Niebur, New Horizons program scientist at NASA Headquarters in Washington. “This mission will obtain images to map Pluto and its moons better than has ever been achieved by any previous planetary mission.”
APL manages the New Horizons mission for NASA's Science Mission Directorate in Washington. Alan Stern, of the Southwest Research Institute (SwRI), headquartered in San Antonio, is the principal investigator and leads the mission. SwRI leads the science team, payload operations, and encounter science planning. New Horizons is part of the New Frontiers Program managed by NASA's Marshall Space Flight Center in Huntsville, Alabama. APL designed, built and operates the spacecraft.
Credit: pluto.jhuapl.edu
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Posted: 04 Feb 2015 03:15 PM PST
Researchers at the Universidad Politécnica de Madrid and the Instituto de Astrofísica de Canarias are studying the evolution and formation of hundreds of close galaxies and have just published new scientific images. Studying the internal structure and the interaction among galaxies was carried out by researchers of the Space Dynamics Group at UPM in collaboration with the Instituto de Astrofísica de Canarias (IAC). By combining the observational work with post-processed photos, researchers have successfully published new optical images of 1768 nearby galaxies. They have also developed the statistical analysis of their morphology and the interaction among galaxies from the Spitzer Survey of Stellar Structure (S4G). This represents a step forward in the comprehension of the origins of the universe.
Galaxies are made up of millions of stars and their structures depend on the processes in which they evolved, including interactions with other nearby galaxies. Galaxies are a key element in cosmology, since the understanding of their structure is an approach to the phenomena that govern the formation of the universe.
In order to make progress, researchers at the School of Aeronautics and Space Engineering in collaboration with IAC have analyzed almost 3,000 nearby galaxies observed within the framework of Spitzer Survey of Stellar Structure (S4G), an exploration conducted by the Spitzer Space Telescope. The infrared images taken by Spitzer were complemented with optical images taken from other sources such as the Sloan Digital Sky Survey (Apache Point Observatory, Nuevo México, USA) and the Liverpool Telescope at the Observatorio de Roque de los Muchachos in La Palma (Spain).
These optical images have been properly reprocessed during this project and were made available to the scientific community. Thanks to this new image collection, researchers have completed two-thirds of the S4G.
Based on these images, researchers have carried out a statistical study of the morphology, composition and interaction among the galaxies.
The presence of a nearby galaxy can distort the morphology of another galaxy due to gravity. A visual inspection is not enough to determine whether two galaxies are close because researchers need to take into account the magnitude and relative speed between them. Within the framework of this project, the processed images have been contrasted with the physical data from the NASA/IPAC Extragalactic Database (NED). Therefore, researchers can establish objective and measurable criteria to verify whether two galaxies are indeed close.
As a result of this study, it is estimated that nearly the 17% of the observed galaxies are close neighbors and the 3% of the galaxies show important signs of interaction. Additionally, they found that 32 galaxies show evidence of merging with their neighbors. Lastly, they established diverse categories to set the interaction level among neighboring galaxies.
Credit: upm.es
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Posted: 04 Feb 2015 02:24 PM PST
Space travel is difficult and expensive – it would cost thousands of dollars to launch a bottle of water to the moon. The recent discovery of hydrogen-bearing molecules, possibly including water, on the moon has explorers excited because these deposits could be mined if they are sufficiently abundant, sparing the considerable expense of bringing water from Earth. Lunar water could be used for drinking or its components – hydrogen and oxygen – could be used to manufacture important products on the surface that future visitors to the moon will need, like rocket fuel and breathable air. Recent observations by NASA's Lunar Reconnaissance Orbiter (LRO) spacecraft indicate these deposits may be slightly more abundant on crater slopes in the southern hemisphere that face the lunar South Pole. "There’s an average of about 23 parts-per-million-by-weight (ppmw) more hydrogen on Pole-Facing Slopes (PFS) than on Equator-Facing Slopes (EFS)," said Timothy McClanahan of NASA's Goddard Space Flight Center in Greenbelt, Maryland.
This is the first time a widespread geochemical difference in hydrogen abundance between PFS and EFS on the moon has been detected. It is equal to a one-percent difference in the neutron signal detected by LRO's Lunar Exploration Neutron Detector (LEND) instrument. McClanahan is lead author of a paper about this research published online October 19 in the journal Icarus.
The hydrogen-bearing material is volatile (easily vaporized), and may be in the form of water molecules (two hydrogen atoms bound to an oxygen atom) or hydroxyl molecules (an oxygen bound to a hydrogen) that are loosely bound to the lunar surface. The cause of the discrepancy between PFS and EFS may be similar to how the Sun mobilizes or redistributes frozen water from warmer to colder places on the surface of the Earth, according to McClanahan.
"Here in the northern hemisphere, if you go outside on a sunny day after a snowfall, you'll notice that there's more snow on north-facing slopes because they lose water at slower rates than the more sunlit south-facing slopes" said McClanahan. "We think a similar phenomenon is happening with the volatiles on the moon – PFS don't get as much sunlight as EFS, so this easily vaporized material stays longer and possibly accumulates to a greater extent on PFS."
The team observed the greater hydrogen abundance on PFS in the topography of the moon's southern hemisphere, beginning at between 50 and 60 degrees south latitude. Slopes closer to the South Pole show a larger hydrogen concentration difference. Also, hydrogen was detected in greater concentrations on the larger PFS, about 45 ppmw near the poles. Spatially broader slopes provide more detectable signals than smaller slopes. The result indicates that PFS have greater hydrogen concentrations than their surrounding regions. Also, the LEND measurements over the larger EFS don't contrast with their surrounding regions, which indicates EFS have hydrogen concentrations that are equal to their surroundings, according to McClanahan. The team thinks more hydrogen may be found on PFS in northern hemisphere craters as well, but they are still gathering and analyzing LEND data for this region.
There are different possible sources for the hydrogen on the moon. Comets and some asteroids contain large amounts of water, and impacts by these objects may bring hydrogen to the moon. Hydrogen-bearing molecules could also be created on the lunar surface by interaction with the solar wind. The solar wind is a thin stream of gas that's constantly blown off the Sun. Most of it is hydrogen, and this hydrogen may interact with oxygen in silicate rock and dust on the moon to form hydroxyl and possibly water molecules. After these molecules arrive at the moon, it is thought they get energized by sunlight and then bounce across the lunar surface; and they get stuck, at least temporarily, in colder and more shadowy areas.
Since the 1960's scientists thought that only in permanently shadowed areas in craters near the lunar poles was it cold enough to accumulate this volatile material, but recent observations by a number of spacecraft, including LRO, suggest that hydrogen on the moon is more widespread.
It's uncertain if the hydrogen is abundant enough to economically mine. "The amounts we are detecting are still drier than the driest desert on Earth," said McClanahan. However, the resolution of the LEND instrument is greater than the size of most PFS, so smaller PFS slopes, perhaps approaching yards in size, may have significantly higher abundances, and indications are that the greatest hydrogen concentrations are within the permanently shaded regions, according to McClanahan.
The team made the observations using LRO's LEND instrument, which detects hydrogen by counting the number of subatomic particles called neutrons flying off the lunar surface. The neutrons are produced when the lunar surface gets bombarded by cosmic rays. Space is permeated by cosmic rays, which are high-speed particles produced by powerful events like flares on the Sun or exploding stars in deep space. Cosmic rays shatter atoms in material near the lunar surface, generating neutrons that bounce from atom to atom like a billiard ball. Some neutrons happen to bounce back into space where they can be counted by neutron detectors.
Neutrons from cosmic ray collisions have a wide range of speeds, and hydrogen atoms are most efficient at stopping neutrons in their medium speed range, called epithermal neutrons. Collisions with hydrogen atoms in the lunar regolith reduce the numbers of epithermal neutrons that fly into space. The more hydrogen present, the fewer epithermal neutrons the LEND detector will count.
The team interpreted a widespread decrease in the number of epithermal neutrons detected by LEND as a signal that hydrogen is present on PFS. They combined data from LEND with lunar topography and illumination maps derived from LRO's LOLA instrument (Lunar Orbiter Laser Altimeter), and temperature maps from LRO's Diviner instrument (Diviner Lunar Radiometer Experiment) to discover the greater hydrogen abundance and associated surface conditions on PFS.
In addition to seeing if the same pattern exists in the moon's northern hemisphere, the team wants to see if the hydrogen abundance changes with the transition from day to night. If so, it would substantiate existing evidence of a very active production and cycling of hydrogen on the lunar surface, according to McClanahan.
The research was funded by NASA's LRO mission. LEND was supplied by the Russian Federal Space Agency Roscosmos. 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.
Credit: NASA
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Posted: 04 Feb 2015 01:45 PM PST
Estonia took a step further in its relations with ESA by signing the Accession Agreement to the ESA Convention on 4 February 2015, to become the 21st ESA Member State. The signing ceremony took place at the ESA Headquarters in Paris with the participation of Jean-Jacques Dordain, ESA Director General, Anne Sulling, Estonian Minister of Economic Affairs and Communications responsible for Foreign Trade and Entrepreneurship, Ene Ergma, Member of Parliament and Head of Estonian Space Committee, and Sven Jürgenson, Estonian Ambassador in France. Other government officials and personalities attended the ceremony, including representatives from the Estonian Space Office of Enterprise Estonia and the Tartu Observatory.
Estonia’s cooperation with ESA started with the signature of a Cooperation Agreement on 20 June 2007 in Tallinn. Estonia strengthened its cooperation with ESA through the European Cooperating State Agreement signed on 10 November 2009.
Estonia has a long tradition in astrophysics research and has contributed to several ESA scientific and technology projects. The country’s active participation in the Plan for European Cooperating States (PECS) covers the fields of space science, Earth observation, life and material sciences and space technology.
Estonia’s first satellite, ESTCube-1, a technology demonstrator designed by the University of Tartu as part of the Estonian Student Satellite Programme, was launched by Vega (flight VV02) on 7 May 2013.
Estonia spent €330 million ($373 million) on space activities in 2009, and has been contributing about €1.2 million per year to the ESA budget as part of a cooperation contract signed in 2010. A dozen Estonia-related space development projects have been initiated since then. Tallinn also supports European space as a member of Eumetsat, a contributor to the EU Common Space development project, and to Europe's Copernicus environmental and monitoring and security system.
Later this year, the Government of Estonia will conclude the ratification process and once the ratification instrument is deposited with the Government of France, Estonia will become officially the 21st ESA Member State.
ESA has 20 Member States: Austria, Belgium, the Czech Republic, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, the Netherlands, Norway, Poland, Portugal, Romania, Spain, Sweden, Switzerland and the United Kingdom, of whom 18 are Member States of the EU. Two other Member States of the EU, Hungary and Estonia, are likely soon to become new ESA Member States.
ESA has Cooperation Agreements with six other Member States of the EU. Canada takes part in some ESA programmes under a Cooperation Agreement.
Credit: ESA
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Posted: 04 Feb 2015 01:06 PM PST
ESA’s Rosetta probe is preparing to make a close encounter with its comet on 14 February, passing just 6 km from the surface. Yesterday was Rosetta’s last day at 26 km from Comet 67P/Churyumov–Gerasimenko, marking the end of the current orbiting period and the start of a new phase for the rest of this year. Today, Rosetta is moving into a new path ahead of a very close encounter next week. First, it will move out to a distance of roughly 140 km from the comet by 7 February, before swooping in for the close encounter at 12:41 GMT (13:41 CET) on 14 February. The closest pass occurs over the comet’s larger lobe, above the Imhotep region. “The upcoming close flyby will allow unique scientific observations, providing us with high-resolution measurements of the surface over a range of wavelengths and giving us the opportunity to sample – taste or sniff – the very innermost parts of the comet’s atmosphere,” says Matt Taylor, ESA’s Rosetta project scientist.
The flyby will take Rosetta over the most active regions of the comet, helping scientists to understand the connection between the source of the observed activity and the atmosphere, or coma.
In particular, they will be looking for zones where the outflowing gas and dust accelerates from the surface and how these constituents evolve at larger distances from the comet.
The comet’s surface is already known to be very dark, reflecting just 6% of the light that falls on it. During the close flyby, Rosetta will pass over the comet with the Sun directly behind, allowing shadow-free images to be collected. By studying the reflectivity of the nucleus as it varies with the angle of the sunlight falling on it, scientists hope to gain a more detailed insight into the dust grains on the surface.
“After this close flyby, a new phase will begin, when Rosetta will execute sets of flybys past the comet at a range of distances, between about 15 km and 100 km,” says Sylvain Lodiot, ESA’s spacecraft operations manager.
It was always planned to change from ‘bound orbits’ to flyby trajectories at this point in the mission, based on predictions of increasing cometary activity. The range of flyby distances also balances the various needs of Rosetta’s 11 instruments in order to optimise the mission’s scientific return.
During some of the close flybys, Rosetta will encounter the comet almost in step with the rotation, allowing the instruments to monitor a single point on the surface as it passes by.
Meanwhile, the more distant flybys will provide the broader context of a wide-angle view of the nucleus and its growing coma.
“We’re in the main science phase of the mission now, so throughout the year we’ll be continuing with high-resolution mapping of the comet,” says Matt.
“We’ll sample the gas, dust and plasma from a range of distances as the comet’s activity increases and then subsides again later in the year.”
Perihelion, closest approach to the Sun, occurs on 13 August when the comet and Rosetta will be 186 million kilometres from the Sun, between the orbits of Earth and Mars.
In the month before perihelion, as activity is reaching a peak, the team are planning to study one of the comet’s jets in greater detail than ever.
“We hope to target one of these regions for a fly-through, to really get a taste of the outflow of the comet,” adds Matt.
After perihelion and once the comet’s activity begins to subside, the mission team will determine if and when to return to a bound orbit around the comet, and how long Rosetta might be able to operate beyond the end of 2015.
Credit: ESA
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