Universe Today

April 13, 2012December 23, 2015 by Jason Major

Hubble Reveals Curious Auroras on Uranus

Bright spots of Uranus' short-lived auroras have been imaged with the Hubble Space Telescope.

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Astronomers have finally succeeded in capturing the first Earth-based images of the curious and fleeting auroras of Uranus using the Hubble Space Telescope, careful planning… and no small amount of luck.

Unlike Earthly auroras, whose long-lived curtains of glowing green, red and purple have been the subject of countless stunning photos over the past months, Uranus’ auroras are relatively dim and short-lived, lasting only several minutes at most. They were first witnessed on Uranus by Voyager 2 in 1986, but never by any Earth-based telescopes until November of 2011. Using Hubble, an international team of astronomers led by Laurent Lamy from the Observatoire de Paris in Meudon, France spotted two instances of auroras on the distant planet… once on November 16 and again on the 29th.

pr_2012-19-hi-res — Two instances of Uranian aurora imaged in Nov. 2011. (L. Lamy)

Auroras are known to be created by a planet’s magnetosphere, which on Earth is aligned closely with the rotational axis — which is why auroras are seen nearest the polar latitudes. But Uranus’ magnetic field is quite offset from its rotational axis, which in turn is tipped nearly 98 degrees relative to its orbital path. In other words, Uranus travels around the Sun rolling on its side! And with a 60-degree difference between its magnetic and rotational axis, nothing on Uranus seems to point quite where it should. This — along with its 2.5-billion-mile (4 billion km) distance — makes for a “very poorly known” magnetic field.

“This planet was only investigated in detail once, during the Voyager flyby, dating from 1986. Since then, we’ve had no opportunities to get new observations of this very unusual magnetosphere,” said Laurent Lamy, lead author of the team’s paper Earth-based detection of Uranus’ aurorae.

Rather than rings of bright emissions, as witnessed on Earth as well as Saturn and Jupiter, the Uranian auroras appeared as bright spots of activity on the planet’s daytime side — most likely a result of Uranus’ peculiar orientation, as well as its seasonal alignment.

It’s not yet known what may be happening on Uranus’ night side, which is out of view of Hubble.

When Voyager 2 passed by Uranus in 1986 the planet was tipped such that its rotational axis was aimed toward the Sun. This meant that its magnetic axis — offset by 60 degrees — was angled enough to encounter the solar wind in much the same way that Earth’s does. This created nightside auroras similar to Earth’s that Voyager saw.

By 2011, however, Uranus — which has an 84-year-long orbit — was near equinox and as a result its magnetic axis was nearly perpendicular with its orbital plane, aiming each end directly into the solar wind once a day. This makes for very different kinds of auroras than what was seen by Voyager; in fact, there’s really nothing else like it that astronomers know of.

“This configuration is unique in the solar system,” said Lamy.

Further investigations of Uranus’ auroras and magnetic field can offer insight into the dynamics of Earth’s own magnetosphere and how it interacts with the solar wind, which in turn affects our increasingly technological society.

The team’s paper will be published Saturday in Geophysical Research Letters, a journal of the American Geophysical Union.

Read the release from the AGU here.

April 13, 2012December 23, 2015 by Nancy Atkinson

Poetry from the Space Station

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Astronaut Don Pettit is not only a scientist and on-orbit fix-it guy extraordinaire, but he is also a poet. Who knew? Since April is National Poetry Month, Pettit has written a couple of poems while on his tour of duty on the International Space Station. “By venturing into unknown territory, discoveries will be made that tickle our imagination and enrich our minds,” he says. “On the frontier, you can once again see the world through the eyes of a child.”

Read two of his recent poems, below:

I Wonder Why

I wonder why the sky is up, and why the stars abound?
And why the Sun comes up each morn, and why the Earth goes ’round?
I wonder what the Sun on Mars, would bring at dusk and dawn?
I wonder what two moons would say, from Earth lit sky when Sun is gone
I wonder if Mars mountain crags would be a sight to hold?
I wonder if I’d dare to climb, how could I be so bold!
I wonder when Man’s mind will grow, and cease to be so small
I wonder when we’ll venture forth, I hope before we fall
I wonder if we’ll never dare, to reach up through the sky
Forever doomed to live on Earth, and this, I wonder why?

Space is My Mistress

Space is my Mistress,
and she beckons my return.
Since our departure I think of you
and yearn to fly across the heavens arm in arm.
I marvel at your figure,
defined by the edges of continents.
You gaze at me with turquoise eyes,
perhaps mistaken for ocean atolls.
You tease me to fall into your bosom,
sculptured by tectonic rifts,
only to move away as if playing some tantalizing game.
Time and time we turn together,
through day, and night, and day,
repeating encounters every 90 minutes with a freshness,
as if we have never seen our faces before.
We stroll outside together,
enveloped by naked cosmos,
filled with desire to be one.
So close,
you sense my every breath,
which masks your stare through visor haze.
We dance on the swirls of cloud tops,
while skirting the islands of blue.
You know my heart beats fast for you.
Oh, Space is my mistress,
and when our orbits coincide,
we will once again make streaks of aurora across the sky.

See more of Pettit’s musings at his NASA blog.

April 13, 2012December 23, 2015 by Ken Kremer

Breaking News – Controversial North Korean Rocket Launch Apparently Fails in Flight

North Korean Unha-3 three stage rocket erected at seaside launch pad days ago. Roxket was launched on April 12 and failed shortly after liftoff

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North Korea has just gone ahead with their announced intentions to defy international warnings and launched the highly controversial Unha-3 long range missile a short while ago at 7:39 AM local time on Friday the 13th (2239 GMT, 6:39 PM EDT Thursday), as reported by CNN, NBC, Fox and other news media on live TV broadcasts at 7 PM EDT, Thursday evening. [Story Updated]

The 3 stage rocket apparently failed in flight quickly and broke apart within the first 90 seconds to 2 minutes and never reached orbit, according to US, Japanese and South Korean officials who have been closely monitoring the developing situation the past few weeks.

Missile tests by North Korea are banned by UN Security Council resolutions.

The White House is expected to issue a statement shortly. Read the official NORAD statement below.

North Korean had invited news media from around the world to view the rocket up close at the launch pad a few days ago, an unprecedented action of openness. But the actual launch and exact timing was not announced ahead of time.

The international reporters who had gathered for the event were caught off guard, in the North Korean capital of Pyongyang, many hundreds of miles distant from the launch site.

The failure is a huge embarrassment to the prestige of the North Korea’s new leader, 28 year old Kim Jong Un, who was promoted to the leadership upon the recent death of his father Kim Jong Il.

Japanese Defense Ministry officials are quoted by NBC and CNN as saying the rocket fell into the ocean after flying about 75 miles. The cause of the rocket failure is not known at this time.

Animation of the planned Unha-3 rocket launch. Credit: Analytical Graphics, Inc. (AGI)

North Korea’s neighbors and the West had strongly condemned North Korean’s launch plans saying this launch was really a disguised test of a military ballistic missile that could be easily converted for military purposes and strike as far as the US West Coast with a nuclear warhead.

North Korean said they were merely launching a small and peaceful experimental weather satellite which they displayed to the media days ago. The timing coincides with the anniversary of the 100th birthday of Kim Il Sung, deceased founding father and former leader of North Korea

The Unha-3 rocket blasted off from the Tongchang-ri, rocket base on North Korea’s west coast near the Chinese border on a southerly course. The trajectory was aimed to skirt along the coasts of South Korea and Japan, causing those countries great concern if the rocket were to develop problems in flight and veer off course and crash on land, potentially causing damage or loss of life in a worst case scenario.

The 90 ton Unha-3 rocket is about 100 feet (30 m) tall.

The UN Security council has scheduled an emergency meeting on Friday in New York to deal with the situation.

There has been no official announcement from the North Korean Government as of this writing.

Further details will be added here as this breaking news story unfolds

—–
NORAD released the following statement this evening April 12, 2012

“North American Aerospace Defense Command (NORAD) and U.S. Northern Command officials acknowledged today that U.S. systems detected and tracked a launch of the North Korean Taepo Dong-2 missile at 6:39 p.m. EDT. The missile was tracked on a southerly launch over the Yellow Sea.”

“Initial indications are that the first stage of the missile fell into the sea 165 km west of Seoul, South Korea. The remaining stages were assessed to have failed and no debris fell on land. At no time were the missile or the resultant debris a threat.”

April 12, 2012December 23, 2015 by Jason Major

A Galaxy’s Bulge Divulges Its Spin

Hubble image of a deformed spiral galaxy in Hydra

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Although somewhat blobby and deformed, this is in fact a spiral galaxy, located in the southern constellation Hydra. Imaged by Hubble as part of a survey of galactic bulges, NGC 4980 exhibits what’s called a “pseudobulge” — an inline central concentration of stars whose similar spiral motion extends right down into its core.

As opposed to classical bulges, in which stars orbit their galaxy’s core in all directions, pseudobulges are made up of stars that continue along the spiral motion of the galactic arms all the way into the center. Pseudobulges are typically seen to contain stars that are the same age as most of the others in the galaxy.

In contrast, classical bulges usually contain stars older than those found in the disk, leading astrophysicists to believe that galaxies with classical bulges had undergone one or more collisions with other galaxies during their evolution.

Our own Milky Way is thought to have a pseudobulge, while some spiral galaxies have no discernible bulge at all.

This image is composed of exposures taken in visible and infrared light by Hubble’s Advanced Camera for Surveys. The image is approximately 3.3 by 1.5 arcminutes in size. NGC 4980 is located about 80 million light-years from Earth.

Read more on ESA’s Hubble site and find out more about galactic bulges on astrobites.com.

Image credit: ESA/Hubble and NASA.

April 12, 2012December 23, 2015 by Nancy Atkinson

Asteroid Lutetia Flyby Animation

All asteroids and comets visited by spacecraft as of November 2010 Credits: Montage by Emily Lakdawalla. Ida, Dactyl, Braille, Annefrank, Gaspra, Borrelly: NASA / JPL / Ted Stryk. Steins: ESA / OSIRIS team. Eros: NASA / JHUAPL. Itokawa: ISAS / JAXA / Emily Lakdawalla. Mathilde: NASA / JHUAPL / Ted Stryk. Lutetia: ESA / OSIRIS team / Emily Lakdawalla. Halley: Russian Academy of Sciences / Ted Stryk. Tempel 1, Hartley 2: NASA / JPL / UMD. Wild 2: NASA / JPL.

In today’s Weekly Space Hangout, Emily Lakdawalla from the Planetary Society mentioned an animation of recently released images from the Rosetta mission’s flyby of asteroid Lutetia. It was put together and processed by Ian Regan, and Emily suggested you play this on a hand-held device (like a smart phone) in a dark room and move it around like you yourself are maneuvering the flyby! Try it — it is a very cool effect!

And while you’re at it, you also need to check out Emily’s montage poster of asteroids and comets, below:

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Check out more pretty images of Lutetia by Emily at the Planetary Blog.

April 12, 2012December 23, 2015 by Nancy Atkinson

The Heavens are Ablaze With Blazars

his image taken by NASA's Wide-field Infrared Survey Explorer (WISE) shows a blazar -- a voracious supermassive black hole inside a galaxy with a jet that happens to be pointed right toward Earth. These objects are rare and hard to find, but astronomers have discovered that they can use the WISE all-sky infrared images to uncover new ones. Image credit: NASA/JPL-Caltech/Kavli

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From a JPL press release:

Astronomers are actively hunting a class of supermassive black holes throughout the universe called blazars thanks to data collected by NASA’s Wide-field Infrared Survey Explorer (WISE). The mission has revealed more than 200 blazars and has the potential to find thousands more.

Blazars are among the most energetic objects in the universe. They consist of supermassive black holes actively “feeding,” or pulling matter onto them, at the cores of giant galaxies. As the matter is dragged toward the supermassive hole, some of the energy is released in the form of jets traveling at nearly the speed of light. Blazars are unique because their jets are pointed directly at us.

“Blazars are extremely rare because it’s not too often that a supermassive black hole’s jet happens to point towards Earth,” said Francesco Massaro of the Kavli Institute for Particle Astrophysics and Cosmology near Palo Alto, Calif., and principal investigator of the research, published in a series of papers in the Astrophysical Journal. “We came up with a crazy idea to use WISE’s infrared observations, which are typically associated with lower-energy phenomena, to spot high-energy blazars, and it worked better than we hoped.”

The findings ultimately will help researchers understand the extreme physics behind super-fast jets and the evolution of supermassive black holes in the early universe.

WISE surveyed the entire celestial sky in infrared light in 2010, creating a catalog of hundreds of millions of objects of all types. Its first batch of data was released to the larger astronomy community in April 2011 and the full-sky data were released last month.

Massaro and his team used the first batch of data, covering more than one-half the sky, to test their idea that WISE could identify blazars. Astronomers often use infrared data to look for the weak heat signatures of cooler objects. Blazars are not cool; they are scorching hot and glow with the highest-energy type of light, called gamma rays. However, they also give off a specific infrared signature when particles in their jets are accelerated to almost the speed of light.

One of the reasons the team wants to find new blazars is to help identify mysterious spots in the sky sizzling with high-energy gamma rays, many of which are suspected to be blazars. NASA’s Fermi mission has identified hundreds of these spots, but other telescopes are needed to narrow in on the source of the gamma rays.

Sifting through the early WISE catalog, the astronomers looked for the infrared signatures of blazars at the locations of more than 300 gamma-ray sources that remain mysterious. The researchers were able to show that a little more than half of the sources are most likely blazars.

“This is a significant step toward unveiling the mystery of the many bright gamma-ray sources that are still of unknown origin,” said Raffaele D’Abrusco, a co-author of the papers from Harvard Smithsonian Center for Astrophysics in Cambridge, Mass. “WISE’s infrared vision is actually helping us understand what’s happening in the gamma-ray sky.”

The team also used WISE images to identify more than 50 additional blazar candidates and observed more than 1,000 previously discovered blazars. According to Massaro, the new technique, when applied directly to WISE’s full-sky catalog, has the potential to uncover thousands more.

“We had no idea when we were building WISE that it would turn out to yield a blazar gold mine,” said Peter Eisenhardt, WISE project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., who is not associated with the new studies. “That’s the beauty of an all-sky survey. You can explore the nature of just about any phenomenon in the universe.”

April 12, 2012April 24, 2023 by Nancy Atkinson

Letter to NASA is Common Ploy in Climate Change Denial

A group of 49 former NASA employees from Johnson Space Center have written a letter to NASA Administrator Charlie Bolden, requesting that the space agency refrain from “unproven and unsubstantiated remarks” regarding how human activities are causing global climate change.

“As former NASA employees, we feel that NASA’s advocacy of an extreme position … is inappropriate,” says the letter. “We believe the claims by NASA and GISS(Goddard Institute for Space Studies) that man-made carbon dioxide is having a catastrophic impact on global climate change are not substantiated.”

The letter was reportedly supported by Leighton Steward from the Heartland Institute, an organization known for its stance of trying to cast doubt on global warming science.

“NASA has always been about looking out to the skies and beyond, not burying our heads in the sand,” climate scientist Michael Mann told Universe Today in an email “This is an old ploy, trying to cobble together a small group of individuals and make it sound like they speak with authority on a matter that they have really not studied closely. In this case, the effort was led by a fossil fuel industry-funded (climate change) denier who works for the Heartland Institute, and sadly he managed to manipulate this group of former NASA employees into signing on to this misguided statement.”

Mann added that 49 people out of tens of thousands of former and current NASA employees is just a tiny fraction, and that “NASA’s official stance, which represents the full current 16,000 NASA scientists and employees, is clear if you go to their website or look at their official publications: human-caused climate change is real, and it represents a challenge we must confront.”

NASA has responded to the letter, inviting those who signed it – which includes Apollo astronauts, engineers and former JSC officials – to join the debate in peer-reviewed scientific literature and public forums.

“NASA sponsors research into many areas of cutting-edge scientific inquiry, including the relationship between carbon dioxide and climate,” wrote Waleed Abdalati, NASA Chief Scientist. “As an agency, NASA does not draw conclusions and issue ‘claims’ about research findings. We support open scientific inquiry and discussion.”

“If the authors of this letter disagree with specific scientific conclusions made public by NASA scientists, we encourage them to join the debate in the scientific literature or public forums rather than restrict any discourse,” Abdalati concluded.

As several different people have noted — including former astronaut Rusty Schweickart who was quoted in the New York Times — most of those who signed the letter are not active research scientists and do not hold degrees in atmospheric sciences or fields related to climate change.

Schweickart, who was not among those who signed the letter, said in the New York Times that those who wrote the letter “have every right to state and argue for their opinion,” and climate scientist Gavin Schmidt added in the article that people stating their views is completely legitimate, “but they are asking the NASA administrator to censor other peoples’ (which is something else entirely).”

The letter from the former NASA employees – including Apollo astronauts Jack Schmitt, Walt Cunningham, Al Worden, and Dick Gordon — chides that since “hundreds of well-known climate scientists and tens of thousands of other scientists publicly declaring their disbelief in the catastrophic forecasts, coming particularly from the GISS leadership, it is clear that the science is NOT settled.”

Schmidt wrote previously on the RealClimate website that he certainly agrees the science is not settled. “No scientists would be scientists if they thought there was nothing left to find out…The reason why no scientist has said this (that the science is settled) is because they know full well that knowledge about science is not binary – science isn’t either settled or not settled. This is a false and misleading dichotomy.”

However, he added, “In the climate field, there are a number of issues which are no longer subject to fundamental debate in the community. The existence of the greenhouse effect, the increase in CO2 (and other GHGs) over the last hundred years and its human cause, and the fact the planet warmed significantly over the 20th Century are not much in doubt.”

For further reading:
Letter from former NASA employees
Letter from Waleed Abdalati
Article by Andrew Revkin in the New York Times
Article by Eric Berger in the Houston Chronicle
NASA’s Climate Change website
Real Climate

April 12, 2012December 23, 2015 by Jason Major

Is This Proof of Life on Mars?

View of Mars from Viking 2 lander, September 1976. (NASA/JPL-Caltech)

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The Curiosity rover is currently on its way to Mars, scheduled to make a dramatic landing within Gale Crater in mid-August and begin its hunt for the geologic signatures of a watery, life-friendly past. Solid evidence that large volumes of water existed on Mars at some point would be a major step forward in the search for life on the Red Planet.

But… has it already been found? Some scientists say yes.

Researchers from universities in Los Angeles, California, Tempe, Arizona and Siena, Italy have published a paper in the International Journal of Aeronautical and Space Sciences (IJASS) citing the results of their work with data obtained by NASA’s Viking mission.

The twin Viking 1 and 2 landers launched in August and September of 1975 and successfully landed on Mars in July and September of the following year. Their principal mission was to search for life, which they did by digging into the ruddy Martian soil looking for signs of respiration — a signal of biological activity.

PIA00529 — A six-inch-deep trench in the Martian soil dug by Viking 1 in February 1977. The goal was to reach a foot below the surface for sampling.

The results, although promising, were inconclusive.

Now, 35 years later, one team of researchers claims that the Viking landers did indeed detect life, and the data’s been there all along.

“Active soils exhibited rapid, substantial gas release,” the team’s report states. “The gas was probably CO2 and, possibly, other radiocarbon-containing gases.”

By applying mathematical complexities to the Viking data for deeper analysis, the researchers found that the Martian samples behaved differently than a non-biological control group.

“Control responses that exhibit relatively low initial order rapidly devolve into near-random noise, while the active experiments exhibit higher initial order which decays only slowly,” the paper states. “This suggests a robust biological response.”

While some critics of the findings claim that such a process of identifying life has not yet been perfected — not even here on Earth — the results are certainly intriguing… enough to bolster support for further investigation into Viking data and perhaps re-evaluate the historic mission’s “inconclusive” findings.

The team’s paper can be found here.

Image credits: NASA/JPL-Caltech. Also, read more on Irene Klotz’s article on Discovery News.

April 12, 2012April 26, 2016 by Jason Major

What’s the Moon Made Of? Earth, Most Likely.

An impact between a Mars-sized protoplanet and early Earth is the most widely-accepted origin of the Moon. Did smaller impacts seed the formation of continents? (NASA/JPL-Caltech)

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Recent research on lunar samples has shown that the Moon may be made of more Earth than green cheese — if by “green cheese” you mean the protoplanet impactor that was instrumental in its creation.

It’s an accepted hypothesis that Earth’s moon was created during an ancient, violet collision between our infant planet and a Mars-sized world called Theia, an event that destroyed Theia and sent part of Earth’s crust and upper mantle into orbit as a brief-lived ring of molten material. This material eventually coalesced to form the Moon, and over the next 4.5 billion years it cooled, became tidally locked with Earth, accumulated countless craters and gradually drifted out to the respectable distance at which we see it today.

Theia’s remains were once assumed to have been a major contributor to the material that eventually formed the Moon. Lunar samples, however, showed that the ratio of oxygen isotopes on the Moon compared to Earth were too similar to account for such a formation. Now, further research by a team led by scientists from The University of Chicago shows that titanium isotopes — an element much more refractive than oxygen — are surprisingly similar between the Moon and Earth, further indicating a common origin.

“After correcting for secondary effects associated with cosmic-ray exposure at the lunar surface using samarium and gadolinium isotope systematics, we find that the ⁵⁰Ti/⁴⁷Ti ratio of the Moon is identical to that of the Earth within about four parts per million, which is only 1/150 of the isotopic range documented in meteorites,” wrote University of Chicago geophysicist Junjun Zhang, lead author of the paper published in the journal Nature Geoscience on March 25.

If the Moon is more Earth than Theia, then what happened to the original impacting body? Perhaps it was made of heavier stuff that sunk deeper into the Moon, or was assimilated into Earth’s mantle, or got lost to space… only more research will tell.

But for now, you can be fairly sure that when you’re looking up at the Moon you’re seeing a piece of Earth, the cratered remnants of a collision that took place billions of years ago.

See the team’s paper here.

Image credit: NASA / JPL-Caltech

April 11, 2012December 23, 2015 by Nancy Atkinson

Help Track the Effects of Light Pollution with GLOBE at Night

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Going on right now is your last chance in 2012 to take just a few minutes to get involved in the GLOBE at Night campaign to measure the brightness of your night sky. GLOBE at Night is a citizen-science project to raise awareness of the impact of light pollution by inviting citizen-scientists to make naked-eye observations of the night sky in your area.

Here’s all the info you need in order to participate in GLOBE at Night:

Participating in GLOBE at Night requires only five easy steps:

1) Find your latitude and longitude.

2) Find Orion, Leo or Crux by going outside more than an hour after sunset (about 8-10pm local time).

3) Match your nighttime sky to one of the provided magnitude charts.

4) Report your observation.

5) Compare your observation to thousands around the world.

You can also use the new web application data submission process. The GLOBE at Night website is easy to use, comprehensive and holds an abundance of background information. The database is usable for comparisons with a variety of other databases, like how light pollution affects the foraging habits of bats.

People in 115 countries have contributed over 75,000 measurements during the past six years, making GLOBE at Night the most successful light pollution awareness campaign to date. So join in and help the cause!