Source: PhysOrg.com
Individual young stars and star clusters in the 'dead' elliptical galaxy, Messier 105
University of Michigan astronomers examined old galaxies and were surprised to discover that they are still making new stars. The results provide insights into how galaxies evolve with time.
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Universe Today
Source: SpaceTelescope
V1 in M31.
Image credit: NASA, ESA and the Hubble Heritage Team (STScI/AURA)
Though the Universe is filled with billions upon billions of stars, the NASA/ESA Hubble Space Telescope has been trained on a single variable star that in 1923 altered the course of modern astronomy. And, at least one famous astronomer of the time lamented that the discovery had shattered his world view.
The star goes by the inauspicious name of Hubble variable number one, or V1, and resides two million light-years away in the outer regions of the neighbouring Andromeda galaxy, or M31. V1 is a special class of pulsating star called a Cepheid variable that can be used to make reliable measurements of large cosmic distances.
The star helped Edwin Hubble show that Andromeda lies beyond our galaxy. Prior to the discovery of V1 many astronomers, including Harlow Shapley, thought spiral nebulae, such as Andromeda, were part of our Milky Way galaxy. Others weren't so sure. In fact, Shapley and Heber Curtis held a public debate in 1920 over the nature of these nebulae. But it took Edwin Hubble's discovery just a few years later to settle the debate.
Hubble sent a letter, along with a light curve of V1, to Shapley telling him of his discovery. After reading the note, Shapley reportedly told a colleague, "Here is the letter that destroyed my Universe." The Universe became a much bigger place after Edwin Hubble's discovery.
In commemoration of this landmark observation, astronomers with the Space Telescope Science Institute's Hubble Heritage Project partnered with the American Association of Variable Star Observers (AAVSO) to study the star. AAVSO observers followed V1 for six months, producing a plot, or light curve, of the rhythmic rise and fall of the star's light. Based on this data, the Hubble Heritage team scheduled Hubble telescope time to capture Wide Field Camera 3 images of the star at its dimmest and brightest light levels.
These observations were presented on 23 May at the meeting of the American Astronomical Society in Boston.
Link: ESA News
Giotto's 1986 encounter with Comet Halley.
Credits: Halley Multicolor Camera Team, Giotto Project, ESA
ESA has lauched a new campaign for comet lovers. If you use Twitter and you are intrigued by comets you will have the opportunity of a lifetime to win a trip to ESA's operations centre in Germany on 15 June and celebrate 25 years of comet exploration. (learn more)
Source: SPACE.com
Astronomers have created the most complete 3-D map of our local universe, revealing new details about our place in the cosmos. The map shows all visible structures out to about 380 million light-years, which includes about 45,000 of our neighboring galaxies (the diameter of the Milky Way is about 100,000 light-years across).(read more)
Source: NASA-Spitzer
Image credit: NASA/JPL-Caltech/University of Toledo
Tiny crystals of a green mineral called olivine are falling down like rain on a burgeoning star, according to observations from NASA's Spitzer Space Telescope.
This is the first time such crystals have been observed in the dusty clouds of gas that collapse around forming stars. Astronomers are still debating how the crystals got there, but the most likely culprits are jets of gas blasting away from the embryonic star.(read more)
Source: NASA Lunar Science Institute
A team of NASA-funded researchers has measured for the first time water from the moon in the form of tiny globules of molten rock, which have turned to glass-like material trapped within crystals. Data from these newly-discovered lunar melt inclusions indicate the water content of lunar magma is 100 times higher than previous studies suggested.
The inclusions were found in lunar sample 74220, the famous high-titanium "orange glass soil" of volcanic origin collected during the Apollo 17 mission in 1972. The scientific team used a state-of-the-art ion microprobe instrument to measure the water content of the inclusions, which were formed during explosive eruptions on the moon approximately 3.7 billion years ago.
The results published in the May 26 issue of Science Express raise questions about aspects of the "giant impact theory" of how the moon was created. That theory predicted very low water content of lunar rock due to catastrophic degassing during the collision of Earth with a Mars-sized body very early in its history. (read more)
Source: NASA SWIFT
Image credit: Gemini Observatory/AURA/NASA/ Levan, Tanvir, Cucchiara, Fox
NASA's Swift satellite has found the most distant gamma-ray burst ever detected. The blast, designated GRB 080913, arose from an exploding star 12.8 billion light-years away. (read more)
Source: Physics World
New results from NASA's Fermi Gamma-Ray Space Telescope appear to confirm a larger-than-expected rate of high-energy positrons reaching the Earth from outer space. This anomaly in the cosmic-ray flux was first observed by the Italian-led PAMELA spacecraft in 2008 and suggests the existence of annihilating dark-matter particles. (read more)
Source: NASA News
Blue straggler stars in the Milky Way bulge.
Credit: NASA, ESA, W. Clarkson (Indiana University and UCLA), and K. Sahu (STScl)
NASA's Hubble Space Telescope has found a rare class of oddball stars called blue stragglers in the hub of our Milky Way, the first detected within our galaxy's bulge.
Blue stragglers are so named because they seemingly lag behind in the aging process, appearing younger than the population from which they formed. While they have been detected in many distant star clusters, and among nearby stars, they never have been seen inside the core of our galaxy.
It is not clear how blue stragglers form. A common theory is that they emerge from binary pairs. As the more massive star evolves and expands, the smaller star gains material from its companion. This stirs up hydrogen fuel and causes the growing star to undergo nuclear fusion at a faster rate. It burns hotter and bluer, like a massive young star.
The findings support the idea that the Milky Way's central bulge stopped making stars billions of years ago. It now is home to aging sun-like stars and cooler red dwarfs. Giant blue stars that once lived there have long since exploded as supernovae. The results have been accepted for publication in an upcoming issue of The Astrophysical Journal. Lead author Will Clarkson of Indiana University in Bloomington, will discuss them today at the American Astronomical Society meeting in Boston. (read more)
Source: Penn State Live
Credit: ASA/CXC/PSU/L.Townsley et al.
According to a wealth of new data from NASA's X-ray Observatory, what scientists are calling a "supernova factory" has come to life in the Carina Nebula, located a mere 7,500 light years from Earth. This discovery may help astronomers to better understand how some of the Milky Way Galaxy's heaviest and youngest stars race through their lives and release newly-forged elements into their surroundings. (read more)
Related News
Carina Nebula: Nearby supernova factory ramps up
Source: NASA/Chandra
Image credit: NASA/CXC/PSU/L.Townsley et al.
A new Chandra image shows the Carina Nebula, a star-forming region in the Sagittarius-Carina arm of the Milky Way a mere 7,500 light years from Earth. Chandra's sharp X-ray vision has detected over 14,000 stars in this region, revealed a diffuse X-ray glow, and provided strong evidence that massive stars have already self-destructed in this nearby supernova factory.(read more)
Source: ESO Science Release eso1117
Star-forming region around the Tarantula Nebula in the Large Magellanic Cloud.
Image credit: ESO/M.-R. Cioni/VISTA Magellanic Cloud survey.
ESO's Acknowledgment: Cambridge Astronomical Survey Unit
An extraordinarily bright isolated star has been found in a nearby galaxy — the star is three million times brighter than the Sun. All previous similar “superstars” were found in star clusters, but this brilliant beacon shines in solitary splendour. The origin of this star is mysterious: did it form in isolation or was it ejected from a cluster? Either option challenges astronomers’ understanding of star formation.(read more)
Source: NASA-Mars Exporation Rovers
Artist's concept of a NASA Mars Exploration Rover.
Image credit: NASA/JPL/Cornell University
NASA is ending attempts to regain contact with the long-lived Mars Exploration Rover Spirit, which last communicated on March 22, 2010.
A transmission that ended on Wednesday, May 25, was the last in a series of attempts. Extensive communications activities during the past 10 months also have explored the possibility that Spirit might reawaken as the solar energy available increased after a stressful Martian winter without much sunlight. With inadequate energy to run its survival heaters, the rover likely experienced colder internal temperatures last year than in any of its prior six years on Mars. Many critical components and connections would have been susceptible to damage from the cold. (read more)
Source: ESA Portugal
The School EBI / JI of Montenegro, Faro established radio contact with the International Space Station on the afternoon of Monday, 23rd . The connection was organized under the program ARISS (Amateur Radio on the International Space Station) that enables radio amateurs around the world come into contact with the station.
At 13h36, the appointed time for bonding, NASA astronaut Catherine Coleman, greeted the students, who waited, anxious and somewhat nervous, by contact, made from the school auditorium. The twenty questions drawn up by many other students from the 7th to 9th grade, were put one by one, a call lasting 15 minutes.
NASA's Astronaut Cattherine Coleman.
Image credit: NASA.
"What is the biggest fright caught in space?","Do astronauts in orbit feel more homesick?" or "What is the future of the station?", were some of the questions made by students from Algarve. Besides the students and teachers in the auditorium, the remaining school population could also assist communication, since this was broadcast on LiveStream.
"Students have a great fascination about Space matters and are highly motivated for these activities, " says Professor of Physics and Chemistry, Patricia Raposo, a major local leader of the initiative.
Patricia Raposo had participated last June in a summer school for secondary school teachers, sponsored by the European Space Agency at its facilities in ESTEC, the Netherlands. This provided the idea to participate in ARISS. Almost a year after application, the call happened.
Amateurs prepare radio transmission.
Image credit: EBI-JI Montenegro.
This is the first time a school of Algarve participates in the program . This remarkable event was only possible thanks to the "extraordinary collaboration of the Network of Amateur Radio Transmitters and Portuguese Club of Loulé, ' says Patricia Raposo.
School Students EBI / JI of Montenegro ask questions of the astronaut Catherine Coleman.
Image credit: EBI-JI Montenegro.
Source: MESSENGER Mission Highlights
MLA coverage (left) of Mercury as May 21, 2011.
Image credit: NASA/Messenger Mission.
MESSENGER's Mercury Laser Altimeter (MLA) in its first two months of operation has already built up a grid of ground tracks that span most of Mercury’s surface north of the equator. (read more)
Source: Kepler@NASA
Artist's conception of Kepler-10 Stellar Family Portrait.
Image credit: NASA/Ames/JPL-Caltech.
Today Kepler team is announcing another member of the Kepler-10 family, called Kepler-10c (larger foreground object in the image on this page). It has a radius of 2.2 times that of Earth's, and it orbits the star every 45 days. Both Kepler-10b and 10c would be blistering hot worlds.
The Kepler-10 system is located about 560 light-years away near the Cygnus and Lyra constellations. Kepler has discovered two planets around this star. Kepler-10b is, to date, the smallest known rocky exoplanet, or planet outside our solar system (dark spot against yellow sun). This planet, which has a radius of 1.4 times that of Earth's, whips around its star every .8 days. Its discovery was announced in Jan. 2011. (read more)
Fifty years ago, a young president struggling with deepening international issues set a fledgling space agency on a course that would change the history of human exploration. NASA is now commemorating President John F. Kennedy's historic speech that sent humans safely to the moon with a series of activities and a commitment to continue the journey of discovery and exploration that started with a desperate race into space. (learn more)
