New Class of Stellar Explosion Sings the Blues

The four supernovae discovered by the Palomar Transient Factory. Left: before explosion. Right: after explosion. From top to bottom, the supernovae are PTF09atu, PTF09cnd, PTF09cwl, and PTF10cwr. [Credit: Caltech/Robert Quimby/Nature]

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A team of astronomers led by the California Institute of Technology (Caltech) have discovered a new, ultra-bright class of supernova – and it really sings the blues. Possibly one of the most luminous observable objects in the Cosmos, these new types of stellar explosions may help us better understand the origins of starbirth, unravel the mysteries of distant galaxies and even look back into the beginnings of our Universe…

“We’re learning about a whole new class of supernovae that wasn’t known before,” says Robert Quimby, a Caltech postdoctoral scholar and the lead author on a paper to be published in the June 9 on-line issue of the journal Nature. Not only did the team locate four instances of this new class, but the study also helped them unravel the questions behind two previously known supernovae which apparently belong in the same category.

As a graduate student at the University of Texas, Austin, Quimby came to the astronomy forefront in 2007 when he reported the brightest supernova ever found: 100 billion times brighter than the sun and 10 times brighter than most other supernovae. At the time, it was a record. Categorized as 2005ap, it had a rather strange spectral signature – a lack of hydrogen. But Quimby wasn’t the only one in the “class” doing homework, because the Hubble Space Telescope also detected an enigmatic event listed as SCP 06F6. It, too, had an unusual spectrum, but nothing led researchers to surmise it to be similar to 2005ap.

Enter Shri Kulkarni, Caltech’s John D. and Catherine T. MacArthur Professor of Astronomy and Planetary Science and a coauthor on the paper. They enlisted Quimby as a a founding member of the Palomar Transient Factory (PTF) – a project which scans the skies for unrecorded incident flashes of light which could signal possible supernova. With the eye of the 1.2-meter Samuel Oschin Telescope at Palomar Observatory, the colleagues went on to discover an additional four new supernovae events. Measuring the spectra with the 10-meter Keck telescopes in Hawaii, the 5.1-meter telescope at Palomar, and the 4.2-meter William Herschel Telescope in the Canary Islands, the astronomers discovered that all four objects had an unusual spectral signature. Quimby then realized that if you slightly shifted the spectrum of 2005ap—the supernova he had found a couple of years earlier—it looked a lot like these four new objects. The team then plotted all the spectra together. “Boom—it was a perfect match,” he recalls.

From there it didn’t take long to learn to sing the blues. The astronomers quickly figured out that by shifting the spectrum of SCP 06F6 caused it to align with previous findings. The results showed all six supernovae to be a similar type – all with very blue spectra – with the brightest wavelengths shining in the ultraviolet. This was the missing link that connected the two previously unexplained supernovae. “That’s what was most striking about this—that this was all one unified class,” says Mansi Kasliwal, a Caltech graduate student and coauthor on the Nature paper.

Even though astronomers now know these supernovae are related, the rest remains a mystery. “We have a whole new class of objects that can’t be explained by any of the models we’ve seen before,” Quimby says. “What we do know about them is that they are bright and hot—10,000 to 20,000 Kelvin; that they are expanding rapidly at 10,000 kilometers per second; that they lack hydrogen; and that they take about 50 days to fade away—much longer than most supernovae, whose luminosity is often powered by radioactive decay. So there must be some other mechanism that’s making them so bright.”

What could they be? One simulation leads to a pulsational pair-instability and the next points towards a magnetar. No matter what the answer is, the result is the illumination aids astronomers in studying distant dwarf galaxies, allowing them to measure the spectrum of the interstellar gas and uncover their composition. The findings could also “shed light” on what ancient stars may have been like… stretching back into the very beginnings of our Universe. “It is really amazing how rich the night sky continues to be,” Kulkarni says. “In addition to supernovae, the Palomar Transient Factory is making great advances in stellar astronomy as well.”

Original Story Source: California Institute of Technology.

Win a Copy of “Atlas of Astronomical Discoveries”

What are the top 100 discoveries in the history of astronomy? In his book, “Atlas of Astronomical Discoveries,” noted astronomy journalist Govert Schilling tells the story of 400 years of telescopic astronomy. He looks at the most important discoveries since the invention of the telescope, highlighting how astronomers discovered new planets, mapped nebulae, determined the distances to stars, unraveled the structure of the Milky Way, and discovered the expansion of the universe, among other things. And, as telescopes became bigger and more powerful, astronomers delved deeper into the mysteries of the cosmos. It is a beautiful book filled with marvelous images and Schilling’s style of captivating storytelling.

Would you like to have a copy of your very own? Thanks to Springer, and Jeff Rutherford Media Relations, Universe Today has 10 copies of this book to give away! Just send an email to [email protected] with the words “Schilling’s Atlas” in the subject line by Monday, June 13th at 12 Noon PDT to be eligible, and Fraser will randomly pick the winners.

Good luck!

Guest Post: Newly Born: the Science of Astronomy

Astronomical equipment from the ages, on display at the Adler Planetarium. Image: Nancy Atkinson

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Editor’s Note: Astronomy journalist Govert Schilling has written a book that looks at the 100 most important discoveries since the invention of the telescope 400 years ago, called “Atlas of Astronomical Discoveries.” In Schilling’s distinct style, he takes the reader on an adventure through both space and time. Schilling has written this guest post for Universe Today:

Astronomy is a newborn science.

Yes, I know astronomers like to say it’s the oldest science in the world. In a sense, our distant ancestors who wondered about the lights and motions in the night sky were the first practitioners.

But look at it this way: until four centuries ago, we all had the same opportunities in the field. Or lack thereof. Two eyes and a brain – that has been the main instrumentation in astronomy for thousands of years. Not much, really.

Little wonder then that astronomy was in a pretty primitive state at the start of the seventeenth century. Granted, scientists had come to realize that the Sun occupied the center of the solar system, rather than the Earth. They had seen the occasional comet and Stella Nova, and they knew about the slow change in the orientation of the Earth’s axis.

But no one knew the distances to the planets, let alone to the stars. No one had the slightest clue about the true nature of the Sun or the Moon. Meteors were a mystery; planetary satellites and rings were unheard of, and to many, the Milky Way was just that – a cosmic river of milky clouds.

The Milky Way as seen near the Very Large Telescope in the Atacama Desert. Credit: ESO/Y. Beletsky

More importantly, no one realized that the Universe is in a constant state of flux, albeit at an extremely slow pace. That stars were once born and will eventually die. That the planets in our solar system are built from the ashes of an earlier generation of stars. That the Universe hasn’t always been there.

Most of the astronomical knowledge that we take for granted these days, was completely unknown four centuries ago. That’s why I say astronomy is a newborn science.

And the telescope was its midwife.

A replica of Galileo's telescope.

The invention of the telescope, probably around 1600 in the Netherlands, ushered in a whole new scientific era. It paved the way for hundreds of revolutionary discoveries and revealing insights. It brought astronomy to where it is now.

On the occasion of the International Year of Astronomy (2009), I decided to devote a book to the hundred most important astronomical discoveries since the invention of the telescope. Recently translated into English as Atlas of Astronomical Discoveries (Springer, 2011), it is a lavishly illustrated and beautifully designed history tour of the grandest science of all, chockfull with surprising details and personal anecdotes.

What I realized when writing the book was that the young science of astronomy went through a number of very distinct stages, just like a human being goes through childhood, puberty and adolescence before reaching full maturity.

In the seventeenth century, astronomers were like children in a newly opened candy store. Wherever they aimed their rather primitive telescopes, they beheld new discoveries, but this embarrassment of riches was also an undirected endeavour.

During the eighteenth century, the search became more systematic, with diligent observers surveying the skies and taking stock of everything that the telescope brought into view. This was no longer a first reconnaissance, but a real exploratory phase.

Then came the nineteenth century, with the advent of photography and spectroscopy, and the discovery of mysterious cosmic denizens like spiral nebulae, white dwarfs, and interstellar matter. Nature was trying to tell us something profound, and astronomy stood on the threshold of major theoretical breakthroughs that would explain this surprising variety of phenomena.

Finally, the twentieth century saw the emergence of an interconnected, all-encompassing view of cosmic evolution. We discovered the energy source of stars, the true nature of galaxies, the expansion of the Universe, and the humble position of our home planet, both in space and in time. Moreover, we finally understood that the atoms in our bodies were forged in the nuclear ovens of distant suns. That we are truly one with the Universe.

So has astronomy grown into a mature science? With the current generation of giant telescopes, the full exploration of the electromagnetic spectrum, and the advent of space science and computer technology, it’s tempting to answer this question with a resounding ‘yes’. Then again, ninety-six percent of the cosmos consists of mysterious dark matter and dark energy; we have no clue about the origin of our Universe, and no one knows whether or not life – let alone intelligence – is rare or abundant.

Personally, I feel that astronomy is still in its early years. And that’s exactly why it fires the imagination of so many people. The questions that astronomers try to answer are the same questions that a ten-year old would ask. The answers may be difficult, but the questions are simple, because the science is young. What’s it made of? How did it all start? Are we alone?

Certainly, I’d love to see a 2411 edition of Atlas of Astronomical Discoveries, highlighting the hundred most important discoveries and breakthroughs that astronomers made in the 21st, 22nd, 23rd and 24th century. But I’m afraid I wouldn’t understand most of the issues that would be described.

Frankly, I’m glad to live during the youth of my favorite science. After all, I’ve always been fond of the curiosity, energy, creativity and the sheer sense of wonder of children.

Please, astronomy, don’t grow up too soon.

Govert Schilling is an internationally acclaimed astronomy writer in the Netherlands. He is a contributing editor of Sky & Telescope, and his articles have appeared in Science, New Scientist and BBC Sky at Night Magazine. He wrote over fifty books on a wide variety of astronomical topics, some of which have been translated into English, including “Evolving Cosmos; Flash! The Hunt for the Biggest Explosions in the Universe,” TThe Hunt for Planet X,” and “Atlas of Astronomical Discoveries.” In 2007, the International Astronomical Union named asteroid (10986) Govert after him.

More Eye-Popping Video from the June 7 Solar Explosion

Massive coronal mass ejection on. This image shows the size of the Earth to scale. NASA / SDO / J. Major.
Massive coronal mass ejection on. This image shows the size of the Earth to scale. NASA / SDO / J. Major.

Here’s more video from the huge explosion on the Sun on June 7, 2011, which began at about 06:41 UTC. Not only was this event one of the most spectacular ever recorded, but also one of the best observed, with complementary data from several spacecraft and different vantage points. This video shows data from three different space observatories. The Solar Dynamics Observatory’s Atmospheric Imaging Assembly recorded the amazing event in stunning detail in different wavelengths. Additionally, the Solar & Heliospheric Observatory’s (SOHO) LASCO coronagraph and STEREO’s (Solar Terrestrial Relations Observatory) SECCHI instrument suite observed the prominence and associated CME as they traveled out into the heliosphere. Using LASCO and SECCHI data, the speed of the leading edge of the CME was estimated to be in the range 1200 – 1600 km/s. Model calculations predict that Earth will receive a glancing blow of the CME on June 10, possibly sparking some nice aurorae at high latitudes, according to the SDO team.

The citizen science project Solar Storm Watch predicts a solar storm to reach Earth at 08:00 UTC on June 10, 2011 with a glancing blow 35 degrees behind Earth, with a second storm expected at 19:00 UTC on June 10, 2011, with another glancing blow 32 degrees behind Earth.

The event originated from the almost spotless active region 11226 and was associated with a moderate M2-class X-ray flare. The CME and associated shock wave produced and S1-class radiation storm, which shows up as speckles in the LASCO movies.

The size of the prominence is thought to be at least 75 times the size of Earth. Our Jason Major created a graphic showing the size comparison. Earth is the little teeny tiny blue circle in the top left corner:

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Galaxy Shapes

Galaxy Shapes
Image credit: NASA/JPL-Caltech/UCLA

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Science revealed to us that universe as we know it, is composed of billions of galaxies like our own Milky Way. When you consider how many stars are just in our own galaxy you can get just a small idea how big our universe really is. Despite this astronomers have made great strides in learning more about the galaxies and their different characteristics. One aspect that was defined early was their shapes. Thanks to the work of famous astronomer Edwin Hubble we know that just about any galaxy in the universe will have one of 4 different shapes, spiral, elliptical, lenticular, and irregular.

Spiral galaxies are one of the most familiar galaxy shapes. In fact when most people think of a galaxy, this type of galaxy shape is the first to come to mind. This is because the Milky Way is a prime example of a spiral galaxy. A spiral galaxy looks like a pinwheel. It is basically the nucleus with its different “arms” spiraling outwards. Spiral galaxies can be tight or loose to varying degrees. One important fact about spiral galaxies is that young stars are formed in the outer arms while older stars are found near the center.

The next two types of galaxies are elliptical and lenticular shaped galaxies. These types are the kinds that are the most similar. First they have few or no dust lanes and are largely composed of older mature stars. These types seldom have star forming areas. Of the four galaxy shapes this is the most cohesive and organized.

The final galaxy shape is the irregular galaxy shape. Irregulars have an indeterminate shape. These galaxies are often small and don’t have enough gravitational force to organize into a more regular form. The Hubble telescope has taken images of famous irregular galaxies like the Magellanic Clouds. Irregular galaxies can also be large galaxies that have undergone a major gravitational disturbance.

As you now see the four basic galaxy shapes seem to cover just about every type of galaxy out there. Like any classification of shape there are also subcategories. An interesting observation recently made about the shape of galaxies is the role that their formation plays in determining their shape. It is now thought that galaxies get their shape as they naturally develop, merge with other galaxies or disrupt each other’s path. This is another great mystery as we don’t currently have the technology to plot out the complete paths of galaxies in the universe.

We have written many articles about galaxy shapes for Universe Today. Here’s an article about irregular galaxy, and here’s an article about spiral galaxy.

If you’d like more info on galaxies, check out Hubblesite’s News Releases on Galaxies, and here’s NASA’s Science Page on Galaxies.

We’ve also recorded an episode of Astronomy Cast about galaxies. Listen here, Episode 97: Galaxies.

Source:
http://www.oneminuteastronomer.com/OMALibrary/galaxy-shapes.html

Soyuz Launches With New “International” Space Station Crew

In an epitome of internationalism, an international crew of three new ISS crew members — NASA astronaut Mike Fossum, Russian cosmonaut Sergei Volkov and Japan Aerospace Exploration Agency astronaut Satoshi Furukawa — launched from the Baikonur Cosmodrome in Kazakhstan aboard the Soyuz TMA-02M spacecraft at 4:12 p.m. EDT (2:12 a.m. Wednesday, Baikonur time) beginning their two-day journey to the space station. They are expected to dock at the ISS 4:22 p.m. Thursday, June 9.
Continue reading “Soyuz Launches With New “International” Space Station Crew”

NASA Releases Spectacular Portrait Photos of Endeavour Docked at the ISS from Soyuz and Paolo Nespoli

First Ever Portrait of the International Space Station and docked Shuttle Endeavour from Soyuz capsule. This image of the International Space Station and the docked Space Shuttle Endeavour, flying at an altitude of 220 miles was taken by Expedition 27 crew member Paolo Nespoli from the Soyuz TMA-20 following its undocking on May 23, 2011. It is the first-ever image of a space shuttle docked to the International Space Station. Endeavour at left. European ATV cargo carrier at right. Credit: NASA/Paolo Nespoli

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NASA has at last today (June 7) released the spectacular portrait photos of Endeavour docked at the International Space Station (ISS). These are are the first ever images taken of a space shuttle while still attached to the orbiting lab complex from the perspective of a crewed Russian Soyuz spacecraft.

The breathtaking digital images were captured by Italian astronaut Paolo Nespoli on May 23 through a window inside the Soyuz TMA-20 vehicle as he and two crewmates were departing the ISS for their return trip to Earth.

Story Update: Check out the expanded photo gallery of more awesome images released by NASA later today

The ISS/Shuttle stack and Soyuz were flying at an altitude of 220 miles as the Soyuz undocked with Nespoli, Russian cosmonaut Dmitry Kondratyev and NASA astronaut Cady Coleman. After they were about 600 feet away, Mission Control Moscow commanded the ISS to rotate 130 degrees to give a full view of the entire complex from the side.

Nespoli then had about 30 minutes to capture high resolution digital photos and videos of Space Shuttle Endeavour docked to the orbiting lab for the very last time in the midst of her 16 day long final mission; STS-134.

The Soyuz trio landed safely in Kazakhstan later that day.

The imagery was to have been made public a day or two after the landing. But Nespoli accidentally left the SD data cards behind in the Soyuz vehicle, causing them to processed more slowly as part of routine post flight analysis.

Space Shuttle Endeavour and ISS Portrait Photo Gallery

First Ever Portrait of the International Space Station and docked Shuttle Endeavour from Soyuz capsule
This image of the International Space Station and the docked Space Shuttle Endeavour, flying at an altitude of 220 miles was taken by Expedition 27 crew member Paolo Nespoli from the Soyuz TMA-20 following its undocking on May 23, 2011 (USA time). It is the first-ever image of a space shuttle docked to the International Space Station. Endeavour at top. European ATV cargo carrier at bottom. Credit: NASA/Paolo Nespoli

First ever images of docked Shuttle Endeavour and the ISS from perspective of a Soyuz spacecraft. Credit: NASA/Paolo Nespoli

NASA’s expanding photo gallery here:

Read my earlier features about the portrait photos of Endeavour and the ISS here:
Spectacular Soyuz Photo Gallery shows Unprecedented View Of Shuttle Docked at Station
Ultimate ISS + Shuttle + Earth Photo Op Coming on May 23 from Soyuz and Paolo Nespoli

Read my features about the final mission of Endeavour, STS 134, starting here
STS-134 Shuttle Commander Mark Kelly appears at U2360° Concert in Seattle: Music Video
Era of Space Shuttle Endeavour Ends with June 1 landing at the Kennedy Space Center

Timelapse: Milky Way from the Dakotas

Growing up in the Dakotas, I can attest to the dark skies that grace the northern plains. However, there is also cold weather (even in the spring) and — at times — almost unbelievably windy conditions. But that didn’t stop videographer Randy Halverson from shooting this magnificent timelapse video of the Milky Way. And in fact, his low shots enhance the beauty of the landscape and sky. “There were very few nights, when I could shoot, that were perfectly clear, and often the wind was blowing 25mph +,” Halverson said. “That made it hard to get the shots I wanted. I kept most of the shots low to the ground, so the wind wouldn’t catch the setup and cause camera shake, or blow it over.”

Ten seconds of the video is about 2 hours 20 minutes in real time. Randy tells us he has been doing astro timelapse for only about 16 months, but shooting other types of video since the mid 90’s. See more of his marvelous work at his Dakotalapse website.

Ron Garan’s Videoblog from Space

What is it really like to live in space? ISS astronaut Ron Garan has been steadily communicating his experiences on board the space station since he arrived in April, with his Fragile Oasis blog, his Twitter feed and Twitpic account. Now he’s started a videoblog, to visually and verbally share even more of what it is like to live on the ISS for a long duration mission. His accompanying blog post also includes a transcript and some of the images he talks about.