24
May 11

Black holes spin faster and faster

Source: Royal Astronomical Society


Artist’s impression of  jets emerging from a supermassive black hole.
Credit: Dana Berry / STScI

Two UK astronomers have found that the giant black holes in the centre of galaxies are on average spinning faster than at any time in the history of the Universe. Dr Alejo Martinez-Sansigre of the University of Portsmouth and Prof. Steve Rawlings of the University of Oxford made the new discovery by using radio, optical and X-ray data. They publish their findings in the journal Monthly Notices of the Royal Astronomical Society.(read more)

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24
May 11

Kepler’s Astounding Haul of Multiple Planet Systems

Source: Kepler@NASA


Kepler's discoveries. Image credit: NASA/Wendy Stenzel.

NASA’s Kepler spacecraft is proving itself to be a prolific planet hunter. Within just the first four months of data, astronomers have found evidence for more than 1,200 planetary candidates. Of those, 408 reside in systems containing two or more planets, and most of those look very different than our solar system.

In particular, the Kepler systems with multiple planets are much flatter than our solar system. They have to be for Kepler to spot them. Kepler watches for a planet to cross in front of its star, blocking a tiny fraction of the star’s light. By measuring how much the star dims during such a transit, astronomers can calculate the planet’s size, and by observing the time between successive events they can derive the orbital period – how long it takes the planet to revolve around its star.

To see a transit, the planet’s orbit must be edge-on to our line of sight. To see multiple transiting planets, they all must be edge-on (or nearly so).(read more)

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24
May 11

Satellites monitor Icelandic ash plume

Source: ESA News

 

As Iceland's Grímsvötn volcano spews ash high into the atmosphere, satellite observations are providing essential information to advisory centres assessing the possible hazards to aviation.(read more)

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23
May 11

How to Learn a Star’s True Age

Source: Kepler@NASA


NGC6811. Image credit: Anthony Ayiomamitis.

For many movie stars, their age is a well-kept secret. In space, the same is true of the actual stars. Like our Sun, most stars look almost the same for most of their lives. So how can we tell if a star is one billion or 10 billion years old? Astronomers may have found a solution – measuring the star’s spin.(read more)

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23
May 11

Galileo: Europe prepares for October launch

Source: ESA PR 16-2011


Two Galileo In-Orbit Validation satellites. Credit: ESA

 

The European Space Agency, Arianespace and the European Commission announced today that the launch of the first two satellites of Europe's global navigation satellite system is planned to take place on 20 October.

This will be the first of a series of Galileo satellite launches by Arianespace from Europe's Spaceport in French Guiana.

The announcement follows a detailed review held on 12 May, under the chairmanship of the Director General of the European Space Agency (ESA) and with the participation of Arianespace and industrial prime contractors, which concluded that the space and ground elements will be ready for a launch in October.

The two Galileo satellites will be deployed using a Soyuz launcher. The October launch will mark the inaugural Soyuz flight from its new launch facilities in French Guiana, built in the framework of a programme of the European Space Agency.

Jean-Jacques Dordain, Director General of ESA, pointed out the significance of this launch: "The October launch will be a perfect example of European and international cooperation. On one side we will have the first operational Galileo satellites in orbit, resulting from the cooperation between the European Union and ESA. (read more)

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22
May 11

A prominence breaks free

Source: SOHO Pick of the Week

The STEREO (Ahead) spacecraft observed as a photogenic, solar prominence erupted and broke out into space over about 18-hour period (May 13, 2011). Prominences, notoriously unstable structures, are cooler clouds of gas that float above the Sun's surface, tethered there by magnetic forces. They often erupt and race into space like this one did. The Sun here is being observed in extreme UV light. (view source)

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21
May 11

Radio Telescopes capture best-ever snapshot of Black Hole Jets

Source: NASA News


Jets and radio-emitting lobes emanating from Centaurus A's central black hole.
Image credits: ESO/WFI (visible); NASA/CXC/CfA/R.Kraft et al. (X-ray);
MPIfR/ESO/APEX/A.Weiss et al. (microwave);

An international team, using radio telescopes located throughout the Southern Hemisphere has produced the most detailed image of particle jets erupting from a supermassive black hole in a nearby galaxy.

The new image shows a region less than 4.2 light-years across -- less than the distance between our sun and the nearest star. Radio-emitting features as small as 15 light-days can be seen, making this the highest-resolution view of galactic jets ever made. The study will appear in the June issue of Astronomy and Astrophysics and is available online.(read more)

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20
May 11

Cassini spacecraft and VLT see violent Saturn storm

Source: NASA News


False-color infrared image, obtained by Cassini spacecraft,
shows a powerful storm in Saturn's northern hemisphere.
Image credit: NASA/JPL/Univ. of Arizona.

NASA's Cassini spacecraft and a European Southern Observatory Very Large Telescope (VLT) tracked the growth of a giant early-spring storm in Saturn's northern hemisphere so powerful it stretches around the entire planet. The rare storm has been wreaking havoc for months and shot plumes of gas high into the planet's atmosphere.

Cassini's radio and plasma wave science instrument first detected the large disturbance, and amateur astronomers tracked its emergence in December 2010. As it rapidly expanded, its core developed into a giant, powerful thunderstorm. The storm produced a 3,000-mile-wide (5,000-kilometer-wide) dark vortex, possibly similar to Jupiter's Great Red Spot, within the turbulent atmosphere.

The dramatic effects of the deep plumes disturbed areas high up in Saturn's usually stable stratosphere, generating regions of warm air that shone like bright "beacons" in the infrared. Details are published in this week's edition of Science Magazine. (read more)

Links:

NASA Cassini Mission
ESO Science Release eso1116
NASA Science News

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19
May 11

AMS: ready to discover the particle universe

Source: ESAPortal


AMS-02 instrument being installed to the ISS. Image credit: NASA.

The largest and most complex scientific instrument yet to be fitted to the International Space Station was installed today. Taken into space by the Space Shuttle, the Alpha Magnetic Spectrometer will sift ten thousand cosmic-ray hits every minute, looking for nature’s best-kept particle secrets. (read more)

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19
May 11

Galaxy Evolution Explorer finds Dark Energy repulsive

Source: NASA News


Artist's impression of GALEX.
Image credits: NASA/JPL-Caltech.

A five-year survey of 200,000 galaxies, stretching back seven billion years in cosmic time, has led to one of the best independent confirmations that dark energy is driving our universe apart at accelerating speeds.

The survey used data from NASA's space-based Galaxy Evolution Explorer and the Anglo-Australian Telescope on Siding Spring Mountain in Australia.

The findings offer new support for the favored theory of how dark energy works - as a constant force, uniformly affecting the universe and propelling its runaway expansion. They contradict an alternate theory, where gravity, not dark energy, is the force pushing space apart. According to this alternate theory, with which the new survey results are not consistent, Albert Einstein's concept of gravity is wrong, and gravity becomes repulsive instead of attractive when acting at great distances. (read more)

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18
May 11

Measuring Mercury's magnetic field

Source: MESSENGER Mission


The MESSENGER Magnetometer (MAG) is mounted behind the
spacecraft at the end of a 3.6-m-long boom to ensure that the
instrument is well-separated from fields created by the spacecraft
electronics and moving parts.Image credit: NASA/Messenger.

MESSENGER carries a sensitive Magnetometer that measures the vector magnetic field at the location of the spacecraft. The mission is now trying to map Mercury's magnetic field with an accuracy never achieved before. (read more)

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17
May 11

NASA mission will observe Earth's salty seas for climate clues

Source: NASA/Aquarius


Aquarius - SAC-D Artist's Concept. Image credit: NASA.

Final preparations are under way for the June 9 launch of the international Aquarius/SAC-D observatory. The mission's primary instrument, Aquarius, will study interactions between ocean circulation, the water cycle and climate by measuring ocean surface salinity.

Engineers at Vandenberg Air Force Base in California are performing final tests before mating Aquarius/SAC-D to its Delta II rocket. The mission is a collaboration between NASA and Argentina's space agency, Comision Nacional de Actividades Espaciales (CONAE), with participation from Brazil, Canada, France and Italy. SAC stands for Satelite de Applicaciones Cientificas.

In addition to Aquarius, the observatory carries seven other instruments that will collect environmental data for a wide range of applications, including studies of natural hazards, air quality, land processes and epidemiology.

The mission will make NASA's first space observations of theconcentration of dissolved salt at the ocean surface. Aquarius'  observations will reveal how salinity variations influence ocean circulation, trace the path of freshwater around our planet, and help drive Earth's climate. The ocean surface constantly exchanges water and heat with Earth's atmosphere. Approximately 80 percent of the global water cycle that moves freshwater from the ocean to the atmosphere to the land and back to the ocean happens over the ocean.

Salinity plays a key role in these exchanges. By tracking changes in ocean surface salinity, Aquarius will monitor variations in the water cycle caused by evaporation and precipitation over the ocean, river runoff, the freezing and melting of sea ice. Salinity also makes seawater denser, causing it to sink, where it becomes part of deep, interconnected ocean currents. This deep ocean "conveyor belt" moves water masses and heat from the tropics to the polar regions, helpingto regulate Earth's climate. (read more)

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16
May 11

Free-Floating Planets May Be More Common Than Stars

Source: NASA Science News


Artist's concept of a Jupiter-like planet alone in the dark of space, floating freely without a parent star.
Image credits: NASA/JPL-Caltech

Astronomers have discovered a new class of planets floating alone in the dark of space. These lone worlds are probably outcasts from developing planetary systems and, moreover, they could be twice as numerous as the stars themselves. (read more)

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15
May 11

NASA's Fermi Spots 'Superflares' In The Crab Nebula

Source: NASA-Fermi

The famous Crab Nebula supernova remnant has erupted in an enormous flare five times more powerful than any flare previously seen from the object. On April 12, NASA's Fermi Gamma-ray Space Telescope first detected the outburst, which lasted six days.

The nebula is the wreckage of an exploded star that emitted light which reached Earth in the year 1054. It is located 6500 light-years away in the constellation Taurus. At the heart of an expanding gas cloud lies what is left of the original star's core, a superdense neutron star that spins 30 times a second. With each rotation, the star swings intense beams of radiation toward Earth, creating the pulsed emission characteristic of spinning neutron stars (also known as pulsars).

Apart from these pulses, astrophysicists believed the Crab Nebula was a virtually constant source of high-energy radiation. But in January, scientists associated with several orbiting observatories, including NASA's Fermi, Swift and Rossi X-ray Timing Explorer, reported long-term brightness changes at X-ray energies. (read more)

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14
May 11

Blazing Lights Over Unused Sports Fields

Blazing lights over unused sports fields make no sense at all! We teach our children to turn off unnecessary lights, yet  all around the World neighborhoods waste significant levels of energy and tax money needlessly with poor lighting practices.

It is proven lighting equipped with motion detectors is more effective security lighting than constant-on. This can be useful for the athletic field in many cases. Just like we pay the meters for parking, those who want to light up a volley ball field at night can pay a meter too. There is always the option to play during the day. Better yet, I'd like to see at least a few sports fields serve as StarParks at night and invite families to look through telescopes at public stargazing sessions.
Solar power makes a lot of sense; technology is constantly improving, however, even if energy is free we ought not allow light to trespass outside our own property lines, or directed upwards where it contributes to sky glow that literally travels for 100 ~ 300 kilometers away. Do you know that in many places street lights are deliberately designed to shine onto people's front doors (and inadvertently into bedroom windows)? People should have the option to install a motion-detector light over their own front door if they want it.
Ask your community to rethink outdoor lighting.

Adapted from Facebook cause: Reclaim the night sky: One Star at a Time

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13
May 11

Galileo's data reveals magma Ocean under Jupiter's Moon

Source: NASA-Solar System Exploration

New data analysis from NASA's Galileo spacecraft reveals a subsurface ocean of molten or partially molten magma beneath the surface of Jupiter's volcanic moon Io.

The finding heralds the first direct confirmation of this kind of magma layer at Io and explains why the moon is the most volcanic object known in the solar system. The research was conducted by scientists at the University of California, Los Angeles, the University of California, Santa Cruz, and the University of Michigan.

The study is published this week in the journal Science. (read more)

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12
May 11

Galaxy NGC 4214: A star formation laboratory

Source: ESA/Hubble Photo Release heic1109

Image credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)-ESA/Hubble Collaboration

 

Hubble’s newest camera has taken an image of galaxy NGC 4214. This galaxy glows brightly with young stars and gas clouds, and is an ideal laboratory to research star formation and evolution. (read more)

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11
May 11

Dawn spacecraft captures first image of nearing asteroid

Source: NASA-Dawn

Image processed to show the true size of the giant asteroid Vesta.
Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.

Dawn spacecraft has obtained its first image of the giant asteroid Vesta, which will help fine-tune navigation during its approach. Dawn expects to achieve orbit around Vesta on July 16, when the asteroid is about 117 million miles from Earth.

The image from Dawn's framing cameras was taken on May 3 when the spacecraft began its approach and was approximately 752,000 miles (1.21 million km) from Vesta. The asteroid appears as a small, bright pearl against a background of stars. Vesta also is known as a protoplanet, because it is a large body that almost formed into a planet. (read more)

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10
May 11

Europe’s first EGNOS airport to guide down giant Beluga aircraft

Source: ESA


Beluga transporter. Image credits: NASA/Jim Grossmann

Pau Pyrénées in southern France has become Europe’s first airport to use the new EGNOS Safety-of-Life Service, to guide aircraft in for landing using only this highly accurate space navigation signal. (read more)

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9
May 11

Raging storms sweep away galactic gas

Source: ESA News


An artist’s impression showing a galaxy with a molecular outflow.
Credits: ESA/AOES Medialab

ESA’s Herschel infrared space observatory has detected raging winds of molecular gas streaming away from galaxies. Suspected for years, these outflows may have the power to strip galaxies of gas and halt star formation in its tracks.

The winds that Herschel has detected are extraordinary. The fastest is blowing at a speed of more than 1000 km/s, or about 10 000 times faster than the wind in a terrestrial hurricane.

This is the first time that such molecular gas outflows have been unequivocally observed in a sample of galaxies. This is an important discovery because stars form from molecular gas, and these outflows are robbing the galaxy of the raw material it needs to make new stars. If the outflows are powerful enough, they could even halt star formation altogether. (read more)

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