Really Rocket Science - Astronomy

Billions, in 3D

Thu, 11 Mar 2010 06:37:37 -0800

Satcom types will be gathering in Washington next week for the Satellite 2010 conference and exhibition. It's usually a subdued affair, populated most my men in dark suits. It remains an essential point of contact for people who work in commercial space.

Expect to see a few 3DTV demos, as that's the next "bandwidth hog" the satellite operators are hoping. More bandwidth mean more money.

More exciting is what happens on Friday, 19 March 2010: "Hubble 3D" opens at the Smithsonian National Air and Space Museum's Lockheed Martin IMAX Theater. During the space shuttle final mission to the Hubble Space Telescope (STS-125), they packed an IMAX 3D camera with them.

Here's the trailer...

And another example of what this telescope can do, via DeepAstronomy.com...

Known Universe: The Video

Wed, 23 Dec 2009 06:39:21 -0800

By far the coolest space video ever, via the American Museum of Natural History:

After hovering over Mount Everest and the gorges that plunge to the Ganges, you are pulled through the Earth’s atmosphere to glimpse the inky black of space over Tibet’s high desert. So begins The Known Universe, a new film produced by the American Museum of Natural History that is part of a new exhibition, Visions of the Cosmos: From the Milky Ocean to an Evolving Universe, at the Rubin Museum of Art in New York City.
The magic of this film, though, happens as the inky black expands. Pulling farther and farther from Earth, you see the deep blue of the Pacific give way to night as the Sun comes into focus, the orbits of the solar system shrink smaller and smaller, the constellations Sagittarius and Scorpio stretch and distort, and, as the Milky Way receeds, the spidery structure of millions of other galaxies come into view. Then, you reach the limit of the observable universe, the afterglow of the Big Bang. This light has taken more than 13.7 billion years to reach our planet, and you return, back to Earth, to two lakes that are nestled between Mount Kailash and Mount Gurla Mandhata in the Himalayas.
The structure of The Known Universe is based on precise, scientifically-accurate observations and research. The Hayden Planetarium at the American Museum of Natural History maintains the Digital Universe Atlas, the world’s most complete four-dimensional map of the universe. The Digital Universe started nearly a decade ago. It is continually updated and is the primary resource for production of the Museum’s Space Shows such as the current Journey to the Stars, and is used in live, real-time renderings for Virtual Tours of the Universe, a public program held on the first Tuesday of every month. Last year, some 30,000 people downloaded the Digital Universe to their personal computers, and the Digital Universe will soon be updated with a more accurate and user-friendly software interface. Digital Universe is licensed to many other planetariums and theaters world-wide.
“I liken the Digital Universe to the invention of the globe,” says Curator Ben R. Oppenheimer, an astrophysicist at the Museum. “When Mercator invented the globe, everyone wanted one. He had back orders for years. It gave everyone a new perspective on where they live in relation to others, and we hope that the Digital Universe does the same on a grander, cosmic scale.”
The new film was produced by Michael Hoffman, and directed by Carter Emmart. Brian Abbot manages and Ben R. Oppenheimer curates the Digital Universe Atlas. The exhibition at the Rubin, Visions of the Cosmos: From the Milky Ocean to an Evolving Universe, opened on December 11 and continues through May 10.

The animation was done in Uniview (SCISS AB)

Technorati Tags: uniview sciss amnh hayden+planetarium american+museum+of+natural+history space+animation known+universe

Leonid Love

Thu, 19 Nov 2009 06:10:29 -0800

Amman, Jordan

Norway

South Africa

Guffey, Colorado

The Leonid Meteor Shower was, by most accounts, a modest one this year as between 200 and 300 fell during the peak this week. Apparently, Mongolia was a good place to watch. In the Western U.S., a Bolide meteor caused a huge fireball lit up the sky around midnight. The account, via thespectrum.com:

People from Southern Idaho to Cedar City reported seeing a bright light in the sky shortly after midnight Wednesday, according to an article on KSL.com.

The article says a meteor is the likely cause of the bright light that lit up Utah skies. The earth is currently passing through the Leonids, a spectacular annual meteor shower.

Some northern Utah residents also reported on Facebook that they heard a noise and felt shaking along with the bright light, including one former Washington City resident. There are also reports on Twitter of several “shooting stars” visible in the Hurricane area.

You can follow reactions to the meteor on Twitter by searching for the hash tag #strangelight.

Here's the news report from Fox13 in Utah:

The security cameras at the University of Utah's Milford Observatory's captured this video footage:

Which the AP is running with...

Technorati Tags: bolide+meteor leonids leonid+meteors meteor

Colliding Galaxies

Wed, 04 Nov 2009 12:11:58 -0800

Well done...

Technorati Tags: felicia+day galaxies

Halley's Tail

Wed, 21 Oct 2009 07:31:04 -0700

The Orionids meteor showers peaked this morning as we're passing through the tail of Halley's Comet, via MeteorShowersOnline.com:

The Orionids were frequently observed during the latter years of the 19th century and became the focus of debate during the first quarter of the 20th century. The British amateur astronomer W. F. Denning and the American astronomer C. P. Olivier began using the pages of two astronomical periodicals to debate whether the Orionid radiant, the point from which the meteors seemed to radiate in the sky, moved from one day to the next: Denning argued that it did not, while Olivier argued that it did. Each astronomer had supporters that chimed in, but the argument remained essentially theirs. The problem was that the Orionid radiant was more diffuse than the other well-observed annual meteor showers. Thanks to the use of photography and the very precise plotting of meteors by several amateur and professional astronomers, Oliver was eventually proven correct.

One very unusual feature the Orionids tend to display is an unpredictable maximum. In 1981, observers reported very low rates of less than 10 meteors per hour during the period of October 18 to 21 (maximum predicted for October 21), but high rates of near 20 per hour were noted on the morning of October 23. Interestingly, a study published in Czechoslovakia during 1982, revealed the Orionids generally exhibited a double maximum. The finding was based on observations made during the period spanning 1944 to 1950. Shortly thereafter, several visual studies indicated the presence of a "plateau effect" or a long period of maximum devoid of any sharp decline of activity, instead of a double peak. Most notably, the 1984 observations of the Western Australia Meteor Section, show a nearly flat maximum lasting from October 21 to 24, while N. W. McLeod, III (Florida, USA), has frequently noted it to stretch up to 6 days.

The Leonids, due next month, are more frightening to satellite operators. Especially this year.

Technorati Tags: meteor+showers orionids leonids meteors halley's+comet

DIY Friday: Sidewalk Telescope

Fri, 18 Sep 2009 20:06:18 -0700

Hey, good telescopes aren't cheap. But can you build one yourself? Popular Mechanics published a piece last fall on How to Build a Dobsonian Telescope:

When I set out to build a portable telescope, known as a Dobsonian telescope, the first step had me stymied—where do you find 6 ft of 8-in.-dia cardboard tubing?

I'm a physicist by training, an amateur astronomer by inclination and an occasional visitor to the home center for DIY projects. A massive tube is not usually on my shopping list. I stood in the store with meticulous notes on the materials I needed, but no one could find them. "Um, I think it might be called Sonotube," I repeated, until someone pointed me toward the concrete form tubes in the garden area. And no, my local hardware store did not carry Teflon.

I had heard that building a Dobsonian was simple and inexpensive. This is in fact true—but collecting the materials takes some doing. This is a far cry from John Dobson's experience when he first built the portable, sidewalk telescopes that now bear his name. "We were just scroungers," he tells PM. "The whole thing was made out of junk. The cardboard tubes were lying around. The shingles used to mount the mirror were blown off roofs in storms. We built the mount from window cutouts from schoolhouse doors that had been thrown away." At age 91, Dobson is as passionate about building inexpensive telescopes as he was when he built his first one in 1956. When I brag that the plastics supply store where I finally found Teflon gave me some scrap for free, he exclaims, "Good for you!"

I did not admit to him that I didn't grind my own telescope mirrors—something he did with two porthole windows and sand paper—and that I didn't build my own eyepiece out of binoculars. (Optics these days can be purchased in kits online.) Nonetheless, the instructions I used were very similar to Dobson's original Plans for Building A Sidewalk Telescope. I based my design on the telescope plans provided by Ray Cash, a member of the San Francisco Sidewalk Astronomers, modifying the plans even further with a few ready-made parts.

Dobson claims he didn't invent the sidewalk telescope, as he had lots of help with his early prototypes. However, Dobson did choose to promote his sidewalk telescopes at the cost of his longtime home. After 23 years living in a Vedanta (a branch of Hinduism) monastery, where he built telescopes surreptitiously in the basement and then snuck out at night to introduce the neighborhood kids to the stars, he was told he had to choose between life as a monk or as a telescope builder. That was in 1967. Today, Dobson still tours the world to teach telescope building. The collection process turned out to be an enjoyable treasure hunt—but don't worry, the source list we put together below explains how to find everything. As I sawed and drilled, I murmured a fairly steady mantra to myself of "Why on earth do I have to do that? Oh. Wow. That's brilliant." The design isn't intuitive or obvious, but it is wonderfully elegant.

In essence, it's a telescope built onto a gun mount, which balances through friction as it swivels on an LP record. My total cost was around $400. You may be able to buy a similarly sized commercial telescope at that price these days, but you wouldn't have nearly as much fun. The actual construction took a weekend, and it would be a great project to tackle with kids.

Dobson may be nonchalant about how he used only junk to build his scopes, but it took an impressive mind to figure out how to use that junk in such ingenious ways. Building my telescope, watching it swivel so smoothly, seeing the stars, I basked in the reflected glory of that ingenuity. I am hooked. I want to build another one—and next time, I'm going to grind my own mirrors.

It started in San Francisco with the Sidewalk Astronomers. Find yourself an astronomy club where you are and get into it. This is the International Year of Astronomy. What have you done so far?

Technorati Tags: sidewalk+astronomy dobsonian astronomy+club astronomy diy+telescope

Amateur Astronomer

Fri, 18 Sep 2009 19:42:47 -0700

The Telegraph (U.K.) published an image gallery featuring Astronomy Photograph of the Year Martin Pugh, who happens to be an amateur.

A few words from the photographer: ‘An extremely popular imaging target, it was an absolute “must do” for me. My objective was to produce a high-quality, high-resolution image, blending in Hydrogen-Alpha data to enhance the nebulosity. If I could change something about this photograph I would expand the frame to include the Flame Nebula, and then expand it further to pick up the Great Orion Nebula to create a superlative wide-field vista of this region.’

What’s in the picture: The Horsehead Nebula, is a dark cloud of gas and dust. The gas, dust and other materials condense to form dense knots, which will eventually become stars and planets. New stars have already formed inside part of the dust cloud, as can be seen on the bottom left.

Equipment: SBIG STL11000 CCD camera guided with adaptive optics; 12.5-inch RC Optical Systems Ritchey-Chrétien telescope; Software Bisque Paramount ME mount; 19 hours of exposures

What competition judge Chris Lintott thought: ‘I think this is the perfect deep-sky image; perfectly composed, it grabs your attention straight away. When you look closer, the detail is absolutely stunning, whether it’s the fine structure in the curtain behind the horse or the subtle details on the edge of the dark nebula itself.’

Check out the others on Flickr. Good stuff.

Technorati Tags: astronomy+photos apod astronomy photography

Exoplanet CoRoT-7b

Wed, 16 Sep 2009 08:08:06 -0700

It may not be a catchy name, but the ESO discovery is nevertheless very significant.

The longest set of HARPS measurements ever made has firmly established the nature of the smallest and fastest-orbiting exoplanet known, CoRoT-7b, revealing its mass as five times that of Earth's. Combined with CoRoT-7b's known radius, which is less than twice that of our terrestrial home, this tells us that the exoplanet's density is quite similar to the Earth's, suggesting a solid, rocky world. The extensive dataset also reveals the presence of another so-called super-Earth in this alien solar system.

The ESA's P.R. folks put it in better pespective:

The confirmation of the nature of CoRoT-7b as the first rocky planet outside our Solar System marks a significant step forward in the search for Earth-like exoplanets. The detection by CoRoT and follow-up radial velocity measurements with HARPS suggest that this exoplanet, CoRoT-7b, has a density similar to that of Mercury, Venus, Mars and Earth making it only the fifth known terrestrial planet in the Universe.

The search for a habitable exoplanet is one of the holy grails in astronomy. One of the first steps towards this goal is the detection of terrestrial planets around solar-type stars. Dedicated programmes, using telescopes in space and on ground, have yielded evidence for hundreds of planets outside of our Solar System. The majority of these are giant, gaseous planets, but in recent years small, almost Earth-mass planets have been detected demonstrating that the discovery of Earth analogues – exoplanets with one Earth mass or one Earth radius orbiting a solar-type star at a distance of about 1 astronomical unit – is within reach.

A little too hot for us. The work of astronomers continues, worldwide, day and night.

Technorati Tags: eso la+silla corot-7b esa european+southern+observatory cnes exoplanet

Death of a Star

Thu, 20 Aug 2009 08:57:52 -0700

An optical image from the 0.6-m University of Michigan/CTIO Curtis Schmidt telescope of the brightest Radio Planetary Nebula in the Small Magellanic Cloud, JD 04. The inset box shows a portion of this image overlaid with radio contours from the Australia Telescope Compact Array. The planetary nebula is a glowing record of the final death throes of the star. (Optical images are courtesy of the Magellanic Cloud Emission Line Survey (MCELS) team).

The current Monthly Notices of the Royal Astronomical Society is reporting on super planetary nebulae, with University of Western Sydney Associate Professor Miroslav Filipovic going so far as to call them sexy in an interview with ABC:

Filipovic believes planetary nebula images are the most impressive objects in the galaxy.

"When you look at the Hubble pictures, they are the sexiest pictures you can find," he says.

According to Filipovic, it's important to understand how super planetary nebulae form, particularly as they represent the fate of our Sun.

"This is something that will happen to us in about five billion years from now," he says.

Get a load of the abstract:

We report the extragalactic radio-continuum detection of 15 planetary nebulae (PNe) in the Magellanic Clouds (MCs) from recent Australia Telescope Compact Array+Parkes mosaic surveys. These detections were supplemented by new and high-resolution radio, optical and infrared observations which helped to resolve the true nature of the objects. Four of the PNe are located in the Small Magellanic Cloud (SMC) and 11 are located in the Large Magellanic Cloud (LMC). Based on Galactic PNe the expected radio flux densities at the distance of the LMC/SMC are up to ∼2.5 and ∼2.0 mJy at 1.4 GHz, respectively. We find that one of our new radio PNe in the SMC has a flux density of 5.1 mJy at 1.4 GHz, several times higher than expected. We suggest that the most luminous radio PN in the SMC (N S68) may represent the upper limit to radio-peak luminosity because it is approximately three times more luminous than NGC 7027, the most luminous known Galactic PN. We note that the optical diameters of these 15 Magellanic Clouds (MCs) PNe vary from very small (∼0.08 pc or 0.32 arcsec; SMP L47) to very large (∼1 pc or 4 arcsec; SMP L83). Their flux densities peak at different frequencies, suggesting that they may be in different stages of evolution. We briefly discuss mechanisms that may explain their unusually high radio-continuum flux densities. We argue that these detections may help solve the 'missing mass problem' in PNe whose central stars were originally 1–8 M_⊙ . We explore the possible link between ionized haloes ejected by the central stars in their late evolution and extended radio emission. Because of their higher than expected flux densities, we tentatively call this PNe (sub)sample –'Super PNe'.

Sexy indeed.

Technorati Tags: super+planetary+nebulae wester+sydney astronomy hubble super+pne

Solar Filter

Wed, 29 Jul 2009 05:32:17 -0700

Great shot by Thierry Legault, using special solar filters, of the ISS and shuttle, silhouetted against the Sun. Via OnOrbit

Technorati Tags: thierry+legault sun space+shuttle iss nasa astronomy space+photos

Total Solar Eclipse

Wed, 22 Jul 2009 07:49:22 -0700

Today's news in Asia is about the total solar eclipse, the longest of the century:

The path of the Moon's umbral shadow begins in India and crosses through Nepal, Bangladesh, Bhutan, Myanmar and China. After leaving mainland Asia, the path crosses Japan's Ryukyu Islands and curves southeast through the Pacific Ocean where the maximum duration of totality reaches 6 min 39 s. A partial eclipse is seen within the much broader path of the Moon's penumbral shadow, which includes most of eastern Asia, Indonesia, and the Pacific Ocean.

Check out Xinhua's photo gallery, and, if you can bear it, this TV news report...

Technorati Tags: eclipse solar+eclipse total+solar+eclipse china india asia

Far Out

Tue, 28 Apr 2009 13:39:00 -0700

Tommy Chong of Cheech & Chong said it best: "Far out, man!"

I wonder if somebody at NASA's Goddard Space Flight Center said something similar about this blast from the past, maybe 13 billion light years away:

NASA's Swift satellite and an international team of astronomers have found a gamma-ray burst from a star that died when the universe was only 630 million years old, or less than five percent of its present age. The event, dubbed GRB 090423, is the most distant cosmic explosion ever seen.

"Swift was designed to catch these very distant bursts," said Swift lead scientist Neil Gehrels at NASA's Goddard Space Flight Center in Greenbelt, Md. "The incredible distance to this burst exceeded our greatest expectations -- it was a true blast from the past."

At 3:55 a.m. EDT on April 23, Swift detected a ten-second-long gamma-ray burst of modest brightness. It quickly pivoted to bring its ultraviolet/optical and X-ray telescopes to observe the burst location. Swift saw a fading X-ray afterglow but none in visible light.

"The burst most likely arose from the explosion of a massive star," said Derek Fox at Pennsylvania State University. "We're seeing the demise of a star -- and probably the birth of a black hole -- in one of the universe's earliest stellar generations."

Gamma-ray bursts are the universe's most luminous explosions. Most occur when massive stars run out of nuclear fuel. As their cores collapse into a black hole or neutron star, gas jets -- driven by processes not fully understood -- punch through the star and blast into space. There, they strike gas previously shed by the star and heat it, which generates short-lived afterglows in many wavelengths.

"The lack of visible light alone suggested this could be a very distant object," explained team member Edo Berger of Harvard University.

Beyond a certain distance, the expansion of the universe shifts all optical emission into longer infrared wavelengths. While a star's ultraviolet light could be similarly shifted into the visible region, ultraviolet-absorbing hydrogen gas grows thicker at earlier times. "If you look far enough away, you can't see visible light from any object," he noted.

Within three hours of the burst, Nial Tanvir at the University of Leicester, U.K., and his colleagues reported detection of an infrared source at the Swift position using the United Kingdom Infrared Telescope on Mauna Kea, Hawaii. "Burst afterglows provide us with the most information about the exploded star and its environs," Tanvir said. "But because afterglows fade out so fast, we must target them quickly."

At the same time, Fox led an effort to obtain infrared images of the afterglow using the Gemini North Telescope on Mauna Kea. The source appeared in longer-wavelength images but was absent in an image taken at the shortest wavelength of 1 micron. This "drop out" corresponded to a distance of about 13 billion light-years.

Here's a video of what a gamma ray burst would look like up-close (Credit: NASA/Swift/Cruz deWild):

Technorati Tags: nasa swift gamma+ray+burst gamma+rays space+telescopes grb+090423

Nice Galaxy: NGS 7049

Tue, 07 Apr 2009 19:42:16 -0700

Nice set of pics from Hubble:

The NASA/ESA's Hubble Space Telescope has captured this image of NGC 7049, a mysterious looking galaxy on the border between spiral and elliptical galaxies. NGC 7049 is found in the constellation of Indus, and is the brightest of a cluster of galaxies, a so-called Brightest Cluster Galaxy (BCG). Typical BCGs are some of the oldest and most massive galaxies. They provide excellent opportunities for astronomers to study the elusive globular clusters lurking within.

The globular clusters in NGC 7049 are seen as the sprinkling of small faint points of light in the galaxy’s halo. The halo – the ghostly region of diffuse light surrounding the galaxy – is composed of myriads of individual stars and provides a luminous background to the remarkable swirling ring of dust lanes surrounding NGC 7049's core. Globular clusters are very dense and compact groupings of a few hundreds of thousands of stars bound together by gravity. They contain some of the first stars to be produced in a galaxy. NGC 7049 has far fewer such clusters than other similar giant galaxies in very big, rich groups. This indicates to astronomers how the surrounding environment influenced the formation of galaxy halos in the early Universe.

The image was taken by the Advanced Camera for Surveys on Hubble, which is optimised to hunt for galaxies and galaxy clusters in the remote and ancient Universe, at a time when our cosmos was very young.

Technorati Tags: hubble ngc7049 galaxy

Alfvén Waves

Thu, 19 Mar 2009 20:06:24 -0700

Twisting waves of the Sun's corona can help us understand solar weather, via PhysOrg:

The massive solar twists, known as Alfvén waves, were discovered in the lower atmosphere with the Swedish Solar Telescope in the Canary Islands by scientists from Queen's University Belfast, the University of Sheffield and California State University Northridge.

The increase in solar temperature from approximately 6000 degrees on the visible surface of the Sun (photosphere) to well over a million degrees in the higher overlaying solar corona, has remained at the forefront of astrophysical research for over half a century. The new observations reveal the process behind this phenomenon, whereby these unique magnetic oscillations spread upward from the solar surface to the Sun's corona with an average speed of over 20km per second, carrying enough energy to heat the plasma to well over a few million degrees.

Prof. Mathioudakis, the leader of the Queen's University Belfast Solar Group, said, "Understanding solar activity and its influence on the Earth's climate is of paramount importance for human kind. The Sun is not as quiet as many people think. The solar corona, visible from Earth only during a total solar eclipse, is a very dynamic environment which can erupt suddenly, releasing more energy than 10 billion atomic bombs. Our study makes a major advancement in the understanding of how the million-degree corona manages to achieve this feat."

Alfvén waves are caused by the twisting of structures in the Sun's atmosphere and can be detected by the periodic velocity signals emitted. The Alfvén waves detected in this study were found to be associated with a large magnetic field concentration on the surface of the Sun, approximately twice the size of the British Isles. These strong magnetic fields manifest as bright features, often with lifetimes exceeding one hour. The Swedish Solar Telescope is the largest solar telescope in Europe and produces some of the sharpest images currently available. Bearing in mind that the Sun is 150 million kilometres away, the measurements carried out are equivalent to reading the time on Big Ben in London from Tokyo.

Technorati Tags: alfven+waves corona solar+weather

Green Comet

Mon, 23 Feb 2009 05:10:35 -0800

Comet Lulin's closest approach to Earth is today:

The comet makes its closest approach to Earth (0.41 AU) on Feb. 24, 2009. Current estimates peg the maximum brightness at 4th or 5th magnitude, which means dark country skies would be required to see it. No one can say for sure, however, because this appears to be Lulin's first visit to the inner solar system and its first exposure to intense sunlight. Surprises are possible.

Lulin's green color comes from the gases that make up its Jupiter-sized atmosphere. Jets spewing from the comet's nucleus contain cyanogen (CN: a poisonous gas found in many comets) and diatomic carbon (C2). Both substances glow green when illuminated by sunlight in the near-vacuum of space.

Can't get out or can't see? No worries: Gregg Ruppel of St. Louis has some great images.

Technorati Tags: taiwan comet+lulin green+comet lulin comet