Jason Major, Author at Universe Today

June 7, 2011December 24, 2015 by Jason Major

A White-Hot Relationship

Artist's impression of white dwarf binary pair CSS 41177. Image: Andrew Taylor.

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Two stars have been discovered locked in a mutually-destructive embrace, a relationship that will end with both losing their individual identities as they spiral increasingly closer, eventually becoming a single hot body that is destined to quickly fizzle out.

No, we’re not talking about the cover of a Hollywood tabloid, these are two white dwarf stars 1,140 light-years away in the constellation Leo, and they are the second such pair of their kind ever to be discovered.

Astronomers at the University of Warwick in the UK have identified a binary pair of white dwarf stars named CSS 41177 that circle each other closely in an eclipsing orbit. What’s particularly unique about this pair is that both stars seem to have been stripped down to their helium layers – a feature that points at an unusually destructive history for both.

White dwarfs typically form from larger stars that have burned through their hydrogen and helium, leaving behind hot, dense cores composed of carbon and oxygen – after going through a bloated red giant phase, that is. But when stars are very close to each other, such as in the case of binary pairs, the expanding hydrogen shell from the larger one undergoing its red giant phase is stripped away by its smaller companion, which absorbs the material. Without the compression and heat from the hydrogen layer the first star cannot fuse its helium into heavier elements and is left as a helium white dwarf.

When the time comes for the smaller star to expand into a red giant, its outer layers are likewise torn away by the first star. But the first star cannot use that hydrogen, and so both are left as helium white dwarfs. The unused hydrogen is ultimately lost to the system.

It’s a case of a destructive codependent relationship on a stellar scale.

The white dwarf stars in CSS 41177 will eventually merge together in about a billion years, gaining enough mass in the process to begin fusing their combined helium, thus becoming a single star called a hot subdwarf. This period could last another 100 million years.

This discovery was made using data gathered from the Liverpool Telescope in the Canary Islands and the Gemini Telescope on Hawaii. The paper was accepted for publication in the Astrophysical Journal and is entitled A deeply eclipsing detached double helium white dwarf binary. (Authors: S. G. Parsons, T. R. Marsh, B. T. Gaensicke, A. J. Drake, D. Koester.)

Bringing the Solar System Down to Earth

As a part of NASA’s ongoing Year of the Solar System – which is actually a single Martian year long, or 23 months – the excitement of planetary exploration is being brought to people around the world through a enthusiastic science outreach program called From Earth to the Solar System (FETTSS). A continuation of the well-received International Year of Astronomy 2009 From Earth to the Universe program, FETTSS provides over 90 beautiful high-resolution images of fascinating locations around our solar system; from the ice geysers of Enceladus to the plasma arcs of solar prominences, the cold dunes of Mars to the hot springs of Yellowstone, the FETTSS collection showcases many wonders of many worlds – and helps bring them within view of as many people as possible.

The images are displayed in public locations, hosted by organizations that raise all the necessary funding to have them printed and installed. The FETTSS site exists to provide the high-resolution print images as well as offer guidance as to how to best plan, market and set up an installation.

What’s wonderful about From Earth to the Solar System – as well as its predecessor From Earth to the Universe – is how it brings the fascination of science and astronomy to people who may not have previously given it much thought. By presenting large-format images with descriptive captions in common places – such as in an airport or outside in a public park – FETTSS hosts are actively capturing the interest of viewers and engaging them in astronomy – many undoubtedly for the first time.

People around the world are being connected with the most recent work of scientists and researchers in a way that’s attractive, informative and yet accessible. This is the key to any successful outreach program.

The images are at once artistic and informative, weaving together themes in astrobiology, planetary science, and astronomy. Including contributions from backyard astronomers, large telescopes in space, and even point-and-shoot cameras of field researchers, the collection represents the current state of exploration as seen through the eyes of the scientific community.

Currently an exhibit is just wrapping up in Corpus Christi, Texas, at the Museum of Science and History and was very well-received by both people and the press! The next scheduled event will take place in June at the National Air and Space Museum in Washington, DC.

FETTSS looks to build on the success of the 2009 FETTU program.

“We are hoping to replicate some of FETTU’s success and bring a measure of sustainability to the FETTU concept. ‘From Earth to the Solar System’ is taking a similar grassroots-type of approach to exhibit creation, and will hopefully help remove the barrier to ‘seeking science out’ for some visitors and help make setting up an exhibit more efficient for organizers,” said Kimberly Kowal Arcand, Media Production Coordinator for the Harvard-Smithsonian Center for Astrophysics and FETTSS principal investigator.

“With FETTU – and what we hope to find with FETTSS – there was a wonderful response from both visitors and organizers,” said Arcand. “We found, unexpectedly, a sort of emotional and personal connection to the images in the FETTU project and I’m interested to see if we find that again with FETTSS. I was personally overwhelmed with the response to FETTU… it was the most inspiring thing I have ever worked on!”

Already, exhibitors worldwide have expressed interest in hosting FETTSS installations… from Argentina, Serbia, China, Colombia, Canada, UK, Ireland, Egypt, Spain, Armenia, as well as from numerous locations in the US – many of whom had previously hosted FETTU events.

So with such a great program and strong response, the question remains: what’s next?

“From Earth to the Sun? From Earth to the Galaxies?” suggested Arcand.

With all that’s being discovered, whatever it is it’s sure to be another success!

For more information about FETTSS or to host an FETTSS event in your area, visit the main site here.

May 31, 2011December 24, 2015 by Jason Major

And The Moon Is Eclipsed By The Earth

Total lunar eclipse on December 21, 2010/ Credit: Jason Major

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On June 15 there will be a total lunar eclipse visible from Australia, Indonesia, southern Japan, India, a large area of Asia, Africa, Europe and the eastern part of South America. This is expected to be one of the darkest eclipses ever (with a magnitude of 1.7), second only to the July 2000 eclipse.

Sadly it won’t be visible to viewers in North America, but much of the rest of the world should be treated to a wonderful show as the Moon slips into Earth’s shadow. Gradually growing darker from its western limb inwards, the Moon then gains a bluish cast which transitions to orange then deep red as it moves into light passing through the edge of Earth’s atmosphere (the same as what makes the colors of a sunset) and then eventually going almost completely dark before the process then reverses itself from the opposite side.

Visibility map for June 15 lunar eclipse

The entire eclipse will last 5 hours and 39 minutes, with a totality duration of 1 hour and 40 minutes. It will begin at 17:23 UT.

Viewers in Australia and eastern Asia will see the eclipse begin as the Moon is setting while those in Europe and South America will see it as the Moon is rising. Only locations in India, eastern Africa, the Middle East and western Asia will experience the entire eclipse.

This is the first of two total lunar eclipses in 2011; the next will take place on December 10.

I saw my first total lunar eclipse last December, which took place on the night of the winter solstice (December 21). It really was an amazing event to watch… in totality the Moon was colored a deep coppery red and really just seemed to be suspended among the stars – it felt like you could just reach up and pluck it from the sky! If you are in any of the areas where this next one is visible I encourage you to check it out for yourself!

Read more about lunar eclipses on MrEclipse.com.

Image: Jason Major

May 26, 2011December 24, 2015 by Jason Major

Water, Water Everywhere… Lunar Samples Show More Water Than Previously Thought

Orange lunar soil collected by Apollo 17 contains more water than once thought. Credit: NASA.

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A team of NASA-funded researchers led by Carnegie Institution’s Erik Hauri has recently announced the discovery of more water on the Moon, in the form of ancient magma that has been locked up in tiny crystals contained within soil samples collected by Apollo 17 astronauts. The amounts found indicate there may be 100 times more water within lunar magma than previously thought… truly a “watershed” discovery!

Orange-colored lunar soil sampled during Apollo 17 EVA missions was tested using a new ion microprobe instrument which measured the water contained within magma trapped inside lunar crystals, called “melt inclusions”. The inclusions are the result of volcanic eruptions on the Moon that occurred over 3.7 billion years ago.

Because these bits of magma are encased in crystals they were not subject to loss of water or “other volatiles” during the explosive eruption process.

“In contrast to most volcanic deposits, the melt inclusions are encased in crystals that prevent the escape of water and other volatiles during eruption. These samples provide the best window we have to the amount of water in the interior of the Moon.”

– James Van Orman of Case Western Reserve University, team member

While it was previously found that water is contained within lunar magma during a 2008 study led by Alberto Saal of Brown University in Providence, Rhode Island, this new announcement is based upon the work of Brown undergraduate student Thomas Weinreich, who located the melt inclusions. By measuring the water content of the inclusions, the team could then infer the amount of water present in the Moon’s interior.

The results also make correlations to the proposed origins of the Moon. Currently-accepted models say the Moon was created following a collision between the newly-formed Earth and a Mars-sized protoplanet 4.5 billion years ago. Material from the Earth’s outer layers was blasted out into space, forming a ring of molten material that encircled the Earth and eventually coalesced, cooled and became the Moon. This would also mean that the Moon should have similarities in composition to material that would have been found in the outer layers of the Earth at that time.

“The bottom line is that in 2008, we said the primitive water content in the lunar magmas should be similar to lavas coming from the Earth’s depleted upper mantle. Now, we have proven that is indeed the case.”

– Alberto Saal, Brown University, RI

The findings also suggest that the Moon’s water may not just be the result of comet or meteor impacts – as was suggested after the discovery of water ice in polar craters by the LCROSS mission in 2009 – but may also have come from within the Moon itself via ancient lunar eruptions.

The success of this study makes a strong case for finding and returning similar samples of ejected volcanic material from other worlds in our solar system.

“We can conceive of no sample type that would be more important to return to Earth than these volcanic glass samples ejected by explosive volcanism, which have been mapped not only on the Moon but throughout the inner solar system.”

– Erik Hauri, lead author, Carnegie’s Department of Terrestrial Magnetism

The results were published in the May 26 issue of Science Express.

Read the full NASA news release here.

May 25, 2011December 24, 2015 by Jason Major

Hubble Finds “Oddball” Stars in Milky Way Hub

Astronomers using the Hubble Space Telescope to peer deep into the central bulge of our galaxy have found a population of rare and unusual stars. Dubbed “blue stragglers”, these stars seem to defy the aging process, appearing to be much younger than they should be considering where they are located. Previously known to exist within ancient globular clusters, blue stragglers have never been seen inside our galaxy’s core – until now.

The stars were discovered following a seven-day survey in 2006 called SWEEPS – the Sagittarius Window Eclipsing Extrasolar Planet Search – that used Hubble to search a section of the central portion of our Milky Way galaxy, looking for the presence of Jupiter-sized planets transiting their host stars. During the search, which examined 180,000 stars, Hubble spotted 42 blue stragglers.

Of the 42 it’s estimated that 18 to 37 of them are genuine.

What makes blue stragglers such an unusual find? For one thing, stars in the galactic hub should appear much older and cooler… aging Sun-like stars and old red dwarfs. Scientists believe that the central bulge of the Milky Way stopped making new stars billions of years ago. So what’s with these hot, blue, youthful-looking “oddballs”? The answer may lie in their formation.

Artist's concept of a blue straggler pair. NASA, ESA, and G. Bacon (STScI)

A blue straggler may start out as a smaller member of a binary pair of stars. Over time the larger star ages and gets even bigger, feeding material onto the smaller one. This fuels fusion in the smaller star which then grows hotter, making it shine brighter and bluer – thus appearing similar to a young star.

However they were formed, just finding the blue stragglers was no simple task. The stars’ orbits around the galactic core had to be determined through a confusing mix of foreground stars within a very small observation area. The region of the sky Hubble studied was no larger than the width of a fingernail held at arm’s length! Still, within that small area Hubble could see over 250,000 stars. Incredible.

“Only the superb image quality and stability of Hubble allowed us to make this measurement in such a crowded field.”

– Lead author Will Clarkson, Indiana University in Bloomington and the University of California in Los Angeles

The discovery of these rare stars will help astronomers better understand star formation in the Milky Way’s hub and thus the evolution of our galaxy as a whole.

Multi-Planet Systems Common in Kepler Findings

Artist's concept of Kepler in action. NASA/Kepler mission/Wendy Stenzel.

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Of the 1235 planetary candidates that NASA’s Kepler space telescope has found so far, 408 reside in multiple-planet systems – a growing trend that indicates planets do, in fact, like company.

The systems observed also seem to behave quite differently than our own solar system. In particular many are flatter than ours; that is, the planets orbit their stars in more or less the same exact plane. This, of course, is what allows Kepler to see them in the first place… the planets have to transit their stars perpendicular to Kepler’s point of view in order for it to detect the oh-so-subtle change in brightness that indicates the likely presence of a planet. In our solar system there’s a variation in the orbital plane of some planets up to 7º – enough of a difference that an alien Kepler-esque telescope might very well not be able to spot all eight planets.

The reason for this relative placidity in exoplanet orbits may be due to the lack of gas giants like Jupiter in these systems. So far, all the multiple-planet systems found have planets smaller than Neptune. Without the massive gravitational influence of a Jupiter-sized world to shake things up, these exosystems likely experience a much calmer environment – gravitationally speaking, of course.

“Most likely, if our solar system didn’t have large planets like Jupiter and Saturn to have stirred things up with their gravitational disturbances, it would be just as flat. Systems with smaller planets probably had a much more sedate history.”

– David Latham, Harvard-Smithsonian Center for Astrophysics, Cambridge, MA

Slide showing Kepler multi-planet systems (blue dots). Credit: David Latham.

Systems containing large gas giants have also been found but they are not as flat as those without, and many smaller worlds are indeed out there… “probably including a lot of them comparable in size to Earth,” said planet-hunter Geoff Marcy of the University of California, Berkeley.

While multiple-planet systems were expected, the scientists on the Kepler team were surprised by the amount that have been discovered.

“We didn’t anticipate that we would find so many multiple-transit systems. We thought we might see two or three. Instead, we found more than 100,” said Latham.

A total of 171 multiple-planet systems have been found so far… with many more to come, no doubt!

Announced yesterday at the American Astronomical Society conference in Boston, these findings are the result of only the first four months of Kepler’s observations. There will be another news release next summer but in the meantime the team wants time to extensively research the data.

“We don’t want to get premature information out. There’s still a lot of analysis that needs to be done.”

– Kepler principal investigator William Borucki

Read more on the Kepler mission site, or on Science NOW.

May 23, 2011December 24, 2015 by Jason Major

Kepler Team Announces New Rocky Planet

Artist's impression of Kepler-10c (foreground planet)

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Today at the American Astronomical Society conference in Boston, the Kepler team announced the confirmation of a new rocky planet in orbit around Kepler-10. Dubbed Kepler-10c, this planet is described as a “scorched, molten Earth.”

2.2 times the radius of Earth, Kepler-10c orbits its star every 45 days. Both it and its smaller, previously-discovered sibling 10b are located too close to their star for liquid water to exist.

Kepler-10c was validated using a new computer simulation technique called “Blender” as well as additional infrared data from NASA’s Spitzer Space Telescope. This method can be used to locate Earth-sized planets within Kepler’s field of view and could also potentially help find Earth-sized planets within other stars’ habitable zones.

This is the first time the team feels sure that it has exhaustively ruled out alternative explanations for dips in the brightness of a star… basically, they are 99.998% sure that Kepler-10c exists.

The Kepler-10 star system is located about 560 light-years away near the Cygnus and Lyra constellations.

Read the release on the Nature.com blog.

Image credit: NASA/Ames/JPL-Caltech

May 23, 2011December 24, 2015 by Jason Major

Messages from Mercury

MESSENGER's view from Mercury's south pole

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It’s been just over two months since the MESSENGER spacecraft successfully entered orbit around Mercury, back on March 18, and it’s been enthusiastically returning image after image of our solar system’s innermost planet at a unprecedented rate. Which, of course, is just fine with us!

The image above shows Mercury’s southern hemisphere and the bright rays of the 50-km-wide crater Han Kan. It was acquired on May 17, 2011.

Below are more recent images from MESSENGER… some of which show regions and features that have never previously been mapped – or even named!

Unnamed double peak-ring basin. Acquired May 13.

Detail of the mountains that make up the rim of Caloris Basin. Acquired May 5.

Narrow-angle camera view of the 100-km-wide Atget crater. Acquired May 10.

Color map of Mercury's surface. The bright crater is Snorri (21km wide). Acquired April 15.

Click on the images to see more detail on the MESSENGER mission site.

MESSENGER’s orbit about Mercury is highly elliptical, taking it 200 kilometers (124 miles) above its northern surface at the closest pass and 15,193 kilometers (9,420 miles) away from the south pole at furthest. Check out this video showing an animation of how a typical MESSENGER orbit would be executed.

Image credits: Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington.

The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft’s seven scientific instruments and radio science investigation are unraveling the history and evolution of the Solar System’s innermost planet. During the one-year primary mission, MDIS is scheduled to acquire more than 75,000 images in support of MESSENGER’s science goals.

May 19, 2011December 24, 2015 by Jason Major

Studying Saturn’s Super Storm

Three views of Saturn's northern storm. ESO/University of Oxford/L. N. Fletcher/T. Barry

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First seen by amateur astronomers back in December, the powerful seasonal storm that has since bloomed into a planet-wrapping swath of churning clouds has gotten some scrutiny by Cassini and the European Southern Observatory’s Very Large Telescope array situated high in the Chilean desert.

The image above shows three views of Saturn acquired on January 19: one by amateur astronomer Trevor Barry taken in visible light and the next two by the VLT’s infrared VISIR instrument – one taken in wavelengths sensitive to lower atmospheric structures one sensitive to higher-altitude features.

Cassini image showing dredged-up ammonia crystals in the storm. NASA/JPL/Univ. of Arizona.

While the storm band can be clearly distinguished in the visible-light image, it’s the infrared images that really intrigue scientists. Bright areas can be seen along the path of the storm, especially in the higher-altitude image, marking large areas of upwelling warmer air that have risen from deep within Saturn’s atmosphere.

Normally relatively stable, Saturn’s atmosphere exhibits powerful storms like this only when moving into its warmer summer season about every 29 years. This is only the sixth such storm documented since 1876, and the first to be studied both in thermal infrared and by orbiting spacecraft.

The initial vortex of the storm was about 5,000 km (3,000 miles) wide and took researchers and astronomers by surprise with its strength, size and scale.

“This disturbance in the northern hemisphere of Saturn has created a gigantic, violent and complex eruption of bright cloud material, which has spread to encircle the entire planet… nothing on Earth comes close to this powerful storm.”

– Leigh Fletcher, lead author and Cassini team scientist at the University of Oxford in the United Kingdom.

The origins of Saturn’s storm may be similar to those of a thunderstorm here on Earth; warm, moist air rises into the cooler atmosphere as a convective plume, generating thick clouds and turbulent winds. On Saturn this mass of warmer air punched through the stratosphere, interacting with the circulating winds and creating temperature variations that further affect atmospheric movement.

The temperature variations show up in the infrared images as bright “stratospheric beacons”. Such features have never been seen before, so researchers are not yet sure if they are commonly found in these kinds of seasonal storms.

“We were lucky to have an observing run scheduled for early in 2011, which ESO allowed us to bring forward so that we could observe the storm as soon as possible. It was another stroke of luck that Cassini’s CIRS instrument could also observe the storm at the same time, so we had imaging from VLT and spectroscopy of Cassini to compare. We are continuing to observe this once-in-a-generation event.”

– Leigh Fletcher

A separate analysis using Cassini’s visual and infrared mapping spectrometer confirmed the storm is very violent, dredging up larger atmospheric particles and churning up ammonia from deep in the atmosphere. Other Cassini scientists are studying the evolving storm and a more extensive picture will emerge soon.

Read the NASA article here, or the news release from ESO here.

The leading edge of Saturn's storm in visible RGB color from Cassini raw image data taken on February 25, 2011. (The scale size of Earth is at upper left.) NASA / JPL / Space Science Institute. Edited by J. Major.

May 18, 2011December 24, 2015 by Jason Major

Lone Planets “More Common Than Stars”

Artist's concept of a free-floating Jupiter-like planet. (NASA / JPL-Caltech)

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We happen to live in a solar system where everything seems to be tucked neatly in place. Sun, planets, moons, asteroids, comets… all turning and traveling through space in relatively neat and orderly fashions. But that may not always be the case; sometimes planets can get kicked out of their solar systems entirely, banished to roam interstellar space without a sun of their own. And these “orphan planets” may be much more numerous than once thought.

Researchers in a joint Japan-New Zealand study surveyed microlensing events near the central part of our galaxy during 2006 and 2007 and identified up to 10 Jupiter-sized orphan worlds between 10,000 and 20,000 light-years away. Based on the number of planets identified and the area studied they estimate that there could literally be hundreds of billions of these lone planets roaming our galaxy….literally twice as many planets as there are stars.

“Although free-floating planets have been predicted, they finally have been detected, holding major implications for planetary formation and evolution models.”

– Mario Perez, exoplanet program scientist at NASA Headquarters in Washington.

From the NASA release:

Previous observations spotted a handful of free-floating, planet-like objects within star-forming clusters, with masses three times that of Jupiter. But scientists suspect the gaseous bodies form more like stars than planets. These small, dim orbs, called brown dwarfs, grow from collapsing balls of gas and dust, but lack the mass to ignite their nuclear fuel and shine with starlight. It is thought the smallest brown dwarfs are approximately the size of large planets.

On the other hand, it is likely that some planets are ejected from their early, turbulent solar systems, due to close gravitational encounters with other planets or stars. Without a star to circle, these planets would move through the galaxy as our sun and other stars do, in stable orbits around the galaxy’s center. The discovery of 10 free-floating Jupiters supports the ejection scenario, though it’s possible both mechanisms are at play.

“If free-floating planets formed like stars, then we would have expected to see only one or two of them in our survey instead of 10. Our results suggest that planetary systems often become unstable, with planets being kicked out from their places of birth.”

– David Bennett, a NASA and National Science Foundation-funded co-author of the study from the University of Notre Dame.

The study wasn’t able to resolve planets smaller than Saturn but it’s believed there are likely many more smaller, Earth-sized worlds than large Jupiter-sized ones.

Read the full NASA news release here.

The study, led by Takahiro Sumi from Osaka University in Japan, appears in the May 19 issue of the journal Nature.