Universe Today

June 14, 2011December 24, 2015 by VirtualAstro

Why Can We See Multiple ISS Passes Right Now?

Four ISS passes over the UK last night. Credit: Mark Humpage

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Last night in the UK, US and Europe, we were spoiled with multiple and bright ISS passes. Not just one or two, but up to six passes were able to be viewed throughout the evening in some locations.

This is quite rare as normally we get only one or maybe two visible passes in the evening or morning.

So why are we getting as many as four to six passes per night?

The ISS did receive an orbital boost and its altitude increased by around 20 kilometers. The orbital height of the ISS has an effect on how many visible passes there are at present in the Northern hemisphere. Another reason is because of the time of year.

We are only a week or so away from the Summer Solstice, the time of year when the Northern hemisphere receives the most hours of sunlight. Naturally this means we only have a few hours of darkness and the further North you go, the shorter the nights are and in some locations this time of year, it doesn’t ever get truly dark.

So why does this affect the ISS?

Basically the ISS visible passes have increased due to the station being illuminated much more by the Sun as there are more hours of sunlight right now, but the effect will wear off when we pass through Summer solstice and the nights get longer again.

Take advantage of this rare time and go outside and enjoy the ISS as much as you can in this series of visible passes.

Need to know how and when you can see the ISS? NASA has a Skywatch page where you can find your specific city to look for satellite sighting info.

Spaceweather.com, has a Satellite Tracker Tool. Just put in your zip code (good for the US and Canada) to find out what satellites will be flying over your house.

Heaven’s Above also has a city search, but also you can input your exact latitude and longitude for exact sighting information, helpful if you live out in the country.

June 14, 2011December 24, 2015 by Tammy Plotner

Stellar Super Soaker

A star is born: Swirling gas and dust fall inward, spurring polar jets, shown in blue in this illustration. Illustration courtesy NASA/Caltech

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Located in the constellation of Perseus and just a mere 750 light years from Earth, a young protostar is very busy spewing forth copious amounts of water. Embedded in a cloud of gas and dust, the hundred thousand year old infant is blasting out this elemental life ingredient from both poles like an open hydrant – and its fast moving droplets may be seeding our Universe…

“If we picture these jets as giant hoses and the water droplets as bullets, the amount shooting out equals a hundred million times the water flowing through the Amazon River every second,” said Lars Kristensen, a postdoctoral astronomer at Leiden University in the Netherlands and lead author of the new study detailing the discovery, which has been accepted for publication in the journal Astronomy & Astrophysics.. “We are talking about velocities reaching 200,000 kilometers [124,000 miles] per hour, which is about 80 times faster than bullets flying out of a machine gun.”

To capture the the quicksilver signature of hydrogen and oxygen atoms, the researchers employed the infrared instruments on-board the European Space Agency’s Herschel Space Observatory. Once the atoms were located, they were followed back to the star where they were formed at just a few thousand degrees Celsius. But like hitting hot black top, once the droplets encounter the outpouring of 180,000-degree-Fahrenheit (100,000-degree-Celsius) gas jets, they turn into a gaseous format. “Once the hot gases hit the much cooler surrounding material – at about 5,000 times the distance from the sun to Earth – they decelerate, creating a shock front where the gases cool down rapidly, condense, and reform as water.” Kristensen said.

Like kids of all ages playing with squirt guns, this exciting discovery would appear to be a normal part of a star “growing up” – and may very well have been part of our own Sun’s distant past. “We are only now beginning to understand that sun-like stars probably all undergo a very energetic phase when they are young,” Kristensen said. “It’s at this point in their lives when they spew out a lot of high-velocity material – part of which we now know is water.”

Just like filling summer days with fun, this “star water” may well be enhancing the interstellar medium with life-giving fundamentals… even if that “life” is the birth of another star. The water-jet phenomenon seen in Perseus is “probably a short-lived phase all protostars go through,” Kristensen said. “But if we have enough of these sprinklers going off throughout the galaxy – this starts to become interesting on many levels.”

Skip the towel. I’ll let the Sun dry me off.

Original Story Source: National Geographic.

June 14, 2011December 24, 2015 by Ken Kremer

Test Roving NASA’s Curiosity on Earth

Mars Rover Curiosity, Front View during mobility testing on June 3, 2011. Credit: NASA/JPL-Caltech

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Just over a year from now, NASA’s Curiosity rover should be driving across fascinating new landscapes on the surface of Mars if all goes well. Curiosity is NASA next Mars rover – the Mars Science Laboratory – and is targeted to launch during a three week window that extends from Nov. 25 to Dec. 18, 2011 from Cape Canaveral Air Force Station, Fla..

At NASA’s Jet Propulsion Laboratory (JPL), Pasadena, Calif., engineering specialists have been putting Curiosity through the final phase of mobility tests to check out the driving capability, robotic arm movements and sample collection maneuvers that the robot will carry out while traversing the landing site after plummeting through the Martian atmosphere in August 2012.

Take a good look at this album of newly released images from JPL showing Curiosity from the front and sides, maneuvering all six wheels, climbing obstacles and flexing the robotic arm and turret for science sample collection activities as it will do while exploring the red planet’s surface.

Curiosity is following in the footsteps of the legendary Spirit and Opportunity rovers which landed on opposite side of Mars in 2004.

“The rover and descent stage will be delivered to the Payload Hazardous Servicing Facility at the Kennedy Space Center (KSC) later in June,” Guy Webster, public affairs officer at JPL, told me. An Air Force C-17 transport plane has already delivered the heat shield, back shell and cruise stage on May 12, 2011.

“The testing remaining in California is with engineering models and many operational readiness tests,” Webster elaborated. “Lots of testing remains to be done on the flight system at KSC, including checkouts after shipping, a system test, a fit check with the RTG, tests during final stacking.”

Mars Rover Curiosity, Turning in Place during mobility testin. Credit: NASA/JPL-Caltech

The three meter long rover will explore new terrain that will hopefully provide clues as to whether Mars harbored environmental conditions that may have been favorable to the formation of microbial life beyond Earth and preserved evidence of whether left ever existed in the past and continued through dramatic alterations in Mars history.

NASA is evaluating a list of four potential landing sites that will offer the highest science return and the best chance of finding a potentially habitable zone in a previously unexplored site on the red planet.

June 14, 2011April 26, 2016 by Nancy Atkinson

Astounding Satellite Views of the Puyehue-Cordón Ash Plume

A gigantic plume of ash from the Puyehue-Cordón Volcano in Chile spreads across South America. This image was taken on June 13, 2011 by the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra satellite. Credit: NASA and courtesy Jeff Schmaltz, MODIS Rapid Response Team at NASA GSFC.

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An incredible amount of ash is being spewed from the erupting Puyehue-Cordón Volcano Complex in Chile. This image, taken by the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra satellite on June 13, 2011, shows a large plume of volcanic ash blowing about 780 kilometers east and then northeast over Argentina. A plume of volcanic ash from this eruption disrupted air traffic as far away as New Zealand on June 13. See images below of how far the ash has traveled in the atmosphere, a half a world away.

The Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite acquired the two images below of the Chilean ash plume on June 13, 2011 showing that a concentrated plume was visible more than half a world away. The first image shows the ash plume over southern Australia and the Tasman Sea, while the second image provides a view farther east over New Zealand and the South Pacific Ocean.

The Chilean ash plume over southern Australia and the Tasman Sea on June 13, 2011. Credit: NASA/MODIS on the Aqua Satellite.

The Chilean volcano ash plume over NewZealand and the South Pacific Ocean. Credit: NASA/MODIS on the Aqua satellite.

NASA’s Earth Observatory website says that although the intensity of the eruption has decreased since the initial eruption, the volcano’s activity is holding steady. The plume reached between 4 and 8 kilometers in altitude on June 13, its height varying with the intensity of the eruptive episode throughout the day.

Here’s how the volcano looked back on June 4, 2011 when it began spewing ash 45,000 feet (14,000 meters) into the air. The Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite captured this natural-color image shortly after the eruption began:

Chile’s Puyehue-Cordón Caulle volcano on June 4, 2011. Credit: NASA/Aqua - MODIS

See more images and data on this volcano at the NASA Earth Observatory Natural Hazards website.

You can follow Universe Today senior editor Nancy Atkinson on Twitter: @Nancy_A. Follow Universe Today for the latest space and astronomy news on Twitter @universetoday and on Facebook.

June 14, 2011December 24, 2015 by Nancy Atkinson

STEREO Spacecraft Provides First Complete Image of Sun’s Far Side

First complete image of the far side of the sun taken on June 1, 2011. Click image for larger version. Credit: NASA/STEREO.

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Far out! This is the first complete image of the solar far side, the half of the sun invisible from Earth. Captured on June 1, 2011, the composite image was assembled from NASA’s two Solar TErrestrial RElations Observatory (STEREO) spacecraft. STEREO-Ahead’s data is shown on the left half of image and STEREO-Behind’s data on the right.

You may recall that the two STEREO spacecraft reached opposition (180 degree separation) on February 6 of this year and the science team released a “complete” 360 degree view of the Sun. However, a small part of the sun was inaccessible to their combined view until June 1. This image represents the first day when the entire far side could be seen.

The image is aligned so that solar north is directly up. The seam between the two images is inclined because the plane of Earth’s – and STEREO’s – orbit, known as the “ecliptic”, is inclined with respect to the sun’s axis of rotation. The data was collected by STEREO’s Extreme Ultraviolet Imagers in the SECCHI instrument suites.

The video below explains why seeing the entire Sun is helpful to scientists:

Source: PhysOrg

June 14, 2011December 24, 2015 by Nancy Atkinson

One Year of the Moon in 2.5 Minutes

The New Moon occurs when the Moon and Sun are at the same geocentric ecliptic longitude. The part of the Moon facing us is completely in shadow then. Pictured here is the traditional New Moon, the earliest visible waxing crescent, which signals the start of a new month in many lunar and lunisolar calendars. Credit: NASA Goddard SVC

We don’t always have the time or ability to see the Moon every night of the year, but this video, from the Goddard Space Flight Center Scientific Visualization Studio, uses data from the Lunar Reconnaissance Orbiter and compresses one month into 12 seconds and one year into 2.5 minutes. This is how the Moon will look to us on Earth during the entire year of 2011. While the Moon always keeps the same face to us, it’s not exactly the same face. Because of the tilt in its axis and shape of its orbit, we see the Moon from slightly different angles over the course of a month, and the year. Normally, we don’t see how the Moon “wobbles” in its orbit, but seeing the Moon’s year this quickly, we can see the changes in libration, and axis tilt — as well as the most noticeable changes, the Moon’s phases.

This animation is the most accurate to date, showing shadows and other features on the Moon in incredible detail. This is thanks to the Lunar Orbiter Laser Altimeter (LOLA) aboard LRO. The shadows are based on the global elevation map being developed from measurements by the LOLA, and the instrument has already taken more than 10 times as many elevation measurements as all previous missions combined.

If you want to know what the Moon looks like “right now” this page from the SVC is updated every hour showing the Moon’s geocentric phase, libration, position angle of the axis, and apparent diameter of the Moon. It also has images showing the different phases of the Moon, too.

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Celestial north is up in these images, corresponding to the view from the northern hemisphere. The descriptions of the print resolution stills also assume a northern hemisphere orientation. To adjust for southern hemisphere views, rotate the images 180 degrees, and substitute “north” for “south” in the descriptions.

Source: Goddard Space Flight Center Science Visualization Studio

June 13, 2011December 24, 2015 by Jon Voisey

Measuring Fundamental Constants with Methanol

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Key to the astronomical modeling process by which scientists attempt to understand our universe, is a comprehensive knowledge of the values making up these models. These are generally measured to exceptionally high confidence levels in laboratories. Astronomers then assume these constants are just that – constant. This generally seems to be a good assumption since models often produce mostly accurate pictures of our universe. But just to be sure, astronomers like to make sure these constants haven’t varied across space or time. Making sure, however, is a difficult challenge. Fortunately, a recent paper has suggested that we may be able to explore the fundamental masses of protons and electrons (or at least their ratio) by looking at the relatively common molecule of methanol.

The new report is based on the complex spectra of the methane molecule. In simple atoms, photons are generated from transitions between atomic orbitals since they have no other way to store and translate energy. But with molecules, the chemical bonds between the component atoms can store the energy in vibrational modes in much the same way masses connected to springs can vibrate. Additionally, molecules lack radial symmetry and can store energy by rotation. For this reason, the spectra of cool stars show far more absorption lines than hot ones since the cooler temperatures allow molecules to begin forming.

Many of these spectral features are present in the microwave portion of the spectra and some are extremely dependent on quantum mechanical effects which in turn depend on precise masses of the proton and electron. If those masses were to change, the position of some spectral lines would change as well. By comparing these variations to their expected positions, astronomers can gain valuable insights to how these fundamental values may change.

The primary difficulty is that, in the grand scheme of things, methanol (CH₃OH) is rare since our universe is 98% hydrogen and helium. The last 2% is composed of every other element (with oxygen and carbon being the next most common). Thus, methanol is comprised of three of the four most common elements, but they have to find each other, to form the molecule in question. On top of that, they must also exist in the right temperature range; too hot and the molecule is broken apart; too cold and there’s not enough energy to cause emission for us to detect it. Due to the rarity of molecules with these conditions, you might expect that finding enough of it, especially across the galaxy or universe, would be challenging.

Fortunately, methanol is one of the few molecules which are prone to creating astronomical masers. Masers are the microwave equivalent of lasers in which a small input of light can cause a cascading effect in which it induces the molecules it strikes to also emit light at specific frequencies. This can greatly enhance the brightness of a cloud containing methanol, increasing the distance to which it could be readily detected.

By studying methanol masers within the Milky Way using this technique, the authors found that, if the ratio of the mass of an electron to that of a proton does change, it does so by less than three parts in one hundred million. Similar studies have also been conducted using ammonia as the tracer molecule (which can also form masers) and have come to similar conclusions.

June 13, 2011December 24, 2015 by Tammy Plotner

Carbon Monoxide Reveals Distant Milky Way Arm

The Milky Way's basic structure is believed to involve two main spiral arms emanating from opposite ends of an elongated central bar. But only parts of the arms can be seen - gray segments indicate portions not yet detected. Other known spiral arm segments--including the Sun's own spur--are omitted for clarity. Credit: T. Dame

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Our Milky Way Galaxy’s elemental form is hypothesized to be a barred structure – made up of two major spiral arms originating at both poles of the central bar. But from our vantage point, we can only see portions of those arms. Because of huge amounts of dust literally blocking our view, we can’t be as confident of our structure as other galaxies we can study as a whole. However, by “sniffing our galaxy’s tailpipe”, we’re able to judge our structure just a little bit better.

We’re all aware of theoretical models of the Milky Way… a sprawling, pinwheel-like structure with sweeping, grandiose arms loaded with stars, gases and dust. We’re also aware our Solar System is lodged in a spur of those arms, slowly orbiting and located about 25,000 light-years from the center. But hard and fast details of our Galaxy haven’t been possible until now. Thanks to the use of radio waves, we’re able to cut through the murk and see wavelengths that give us clues. These architectural hints are coming to us in the forms of molecules like carbon monoxide – a great tracer of our galactic format.

Using a small 1.2-meter radio telescope on the roof of their science building in Cambridge, CfA astronomers Tom Dame and Pat Thaddeus used carbon monoxide emissions to ferret out proof there is more spiral structure located in the most distant parts of our galactic home. What they uncovered was a previously reported new spiral arm at the far end of the Scutum-Centaurus Arm – but how they did it was by verifying vast, dense concentrations of this molecular gas.

Where does it come from? Try the “exhaust” of carbon stars. These late-type stars have an atmosphere which is higher in carbon than oxygen. When the two combine in the upper layers of the star they create carbon monoxide. It also happens in “normal” stars like our Sun, too. It’s richer in oxygen than carbon, but still cool enough to form carbon monoxide. “After preliminary Galactic surveys in the mid-1970’s revealed the vast extent of CO emission on the sky,” says Dame, “It became clear that even with the relatively large beams of the 1.2 meter telescopes a sensitive, well-sampled survey of the entire Galaxy would require many years.”

And its time has come…

Original Story Source: Smithsonian Astrophysical Observatory.

June 13, 2011December 29, 2015 by Nancy Atkinson

Carnival of Space #201

Moving on into the second centum of space Carnivals, a brand new CoS is hosted by John Williams over at StarryCritters.

Click here to read the Carnival of Space #201.

And if you’re interested in looking back, here’s an archive to all the past Carnivals of Space. If you’ve got a space-related blog, you should really join the carnival. Just email an entry to [email protected], and the next host will link to it. It will help get awareness out there about your writing, help you meet others in the space community – and community is what blogging is all about. And if you really want to help out, sign up to be a host. Send an email to the above address.

June 12, 2011April 26, 2016 by Tammy Plotner

Coming Up… June 15th Total Lunar Eclipse LIVE

Total lunar eclipse captured January 20-21, 2000. (Courtesy of Mr. Eclipse/Fred Espenak)

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Don’t say we didn’t warn you ahead of time! The upcoming total lunar eclipse will happen on June 15, 2011… and it’s a rare one. This time the Moon will pass directly through the center of the Earth’s shadow cone – an event that hasn’t happened in 11 years and won’t happen again until 2018. The eclipse visibility path will be over Africa, and Central Asia, visible rising over South America, western Africa, and Europe, and setting over eastern Asia. In western Asia, Australia and the Philippines – visible just before sunrise. But before you just read on to another article because you can’t see it from where you live, remember I’ve got a few tricks up my sleeve…

Thanks to this fantastic magic we call the Internet, all you need to do is tune into our friends around the world! The first listing of our live eclipse broadcasters will be Astronomylive.com. Coordinating the eclipse project and different activities for this year is Mohan Sanjeevan, a science and science fiction writer from India. Since May 2011, Mohan volunteers as the Event & Broadcast Organizer of AstronomyLive covering his country. But Mohan is more than just a coordinater, he’s also involved in other venues like writing poetry – including science poems (freelance science writing for more than twenty years; writer of nano science and tech articles for Nano Digest, a monthly magazine from India), popularization of science and creating awareness on global warming, alternative sources of energy and making the planet a more livable place. Space and astronomy are his natural areas of interest. To top it off, Sanjeevan is also a researcher – full of implementable ideas for space and future technologies.

AstronomyLive is a center for LIVE astronomy and you can participate, too! Host your broadcasts of various types on this free service. Amateur astronomers, professional astronomers, observatories, astronomy associations and more are all very welcome. The current team consists of Sander Klieverik, Voskuh and Dennis from the Netherlands, LesD from the United States, Mohan Sanjeevan, Aakanksha, Prof. M. Jothi Rajan, Jhon Kennedy, Bhaskar, Abhilasha and Sanyam Kumar Shrivastava from India. All of these great people came together to share the view with you!

And there’s more…

A free, live webcast from Bareket Observatory in Israel will also feature the total lunar eclipse on June 15, 2011. How do you get there? Simply click on this link for the Bareket Observatory Live Eclipse Broadcast! The hardworking group in Israel invite you to discover the Moon during the eclipse using hands-on eclipse activities. Conduct your own science projects using the live lunar eclipse feed! What a great opportunity for your students, family and friends!

The great folks at Bareket Observatory have expanded tremendously over the years and now they’re pleased to announce the launch of the Astro-Edu Network, a free state-of-the-art astronomy education database for teachers, students and the general public. Among the goals of AStro-Edu is increased communication and understanding within the population of the Middle East using astronomy as the catalyst. Astro-Edu net can be translated to more than 60 different languages using the integrated translation module (move your cursor over the flag in the upper left to translate the materials).

Lunar_eclipse_chart_close-2011jun15 — Lunar Eclipse Timing Chart

So don’t sit out the total lunar eclipse on June 15, 2011 – 17.00 – 23.00 UTC (GMT). Be sure to enjoy the event with our friends around the world!