Solar Powered Plane Soars Over the Golden Gate Bridge

The Solar Impulse airplane flies over the Golden Gate Bridge on April 23, 2013. Credit: Solar Impulse.

The world’s first solar-powered plane is stretching its wings over the US. Today it took off from Moffett Field in Mountain View, California — the home of NASA’s Ames Research Center – and flew to San Fransisco, soaring over the Golden Gate Bridge.

Starting on May 1, Solar Impulse will fly across the US to New York, making several stops along the way as a kind of “get to know you” tour for the US while the founders of Solar Impulse, Swiss pilot Bertrand Piccard and and pilot Andre Borschberg, want to spread their message of sustainability and technology. You can read about the cross-country tour here on UT and also on the Solar Impulse website. You can follow Solar Impulse’s Twitter feed for the latest news of where they are.

Hubble Telescope Captures Image of Comet ISON

Comet ISON was used in a search for time travelers. NASA’s Hubble Space Telescope provides a close-up look of Comet ISON (C/2012 S1), as photographed on April 10. Credit: NASA, ESA, J.-Y. Li (Planetary Science Institute), and the Hubble Comet ISON Imaging Science Team.

Here’s our first good look at Comet (C/2012 S1) ISON. The Hubble Space Telescope captured this shot on April 10, when the comet was slightly closer than Jupiter’s orbit at a distance of 634 million kilometers (394 million miles) from Earth. Later this year, this comet could become a brilliant object in the sky, perhaps 10 times brighter than Venus.

Astronomers say preliminary measurements from the Hubble images suggest that the nucleus of ISON is no larger than 4-6 km (3-4 miles) across.


The astronomers said this is remarkably small considering the high level of activity observed in the comet so far. Astronomers are using these images to measure the activity level of this comet and constrain the size of the nucleus, in order to predict the comet’s activity when it will come with 1.1 million km (700,000 miles) of the Sun on November 28, 2013.

Even though Comet ISON was 620 million km from the Sun when this image was taken, the comet is already active as sunlight warms the surface and causes frozen volatiles to sublimate. A detailed analysis of the dust coma surrounding the solid, icy nucleus reveals a strong, jet blasting dust particles off the sunward-facing side of the comet’s nucleus.

The comet’s dusty coma, or head of the comet, is approximately 5,000 km (3,100 miles) across, or 1.2 times the width of Australia. A dust tail extends more than 92,000 km (57,000 miles), far beyond Hubble’s field of view.

Comet ISON belongs to a special category of comets called sungrazers. As the comet performs a hairpin turn around the Sun in November, its ices will vaporize in the intense solar heat. Assuming it defies death by evaporation, some predict it could become as bright as the full Moon. If so, that would occur for a brief time around at perihelion (closest approach to the Sun) when the comet would only be visible in the daytime sky very close to the Sun. When safely viewed, ISON might look like a brilliant, fuzzy star in a blue sky.

More careful analysis is currently underway to improve these measurements and to predict the possible outcome of the sungrazing perihelion passage of this comet.

ISON stands for International Scientific Optical Network, a group of observatories in ten countries who have organized to detect, monitor, and track objects in space. ISON is managed by the Keldysh Institute of Applied Mathematics, part of the Russian Academy of Sciences.

Source: NASA

Bright Meteor Rocks Argentina Rock Concert

Talk about a light show! A massive bolide was captured on video during a middle-of-the-night rock concert in Argentina on April 21, 2013. The band, Los Tekis performed at an outdoor concert venue and in perfect timing, right after the band concluded a song, the person who shot the video panned out so that the sky was visible — just as the bolide lit up the sky.
Continue reading “Bright Meteor Rocks Argentina Rock Concert”

Incredible Astrophoto: Space Station Flies Over Stonehenge

International Space Station pass over Stonehenge, Wiltshire UK. Credit and copyright: Tim Burgess. Used by permission.

In a gorgeous mix of archeology and space exploration, photographer Tim Burgess captured a stunning view of the International Space Station passing over the historic and iconic Stonehenge on April 20, 2013. Tim said this composite image is composed of 11 shots, 10 sec, f2.8, 400 ISO. As one person commented on Flickr, “An amazing feat of human engineering passing over an amazing feat of human engineering, captured by an amazing feat of human engineering.”

Thanks to Tim for allowing us to post this image on UT; keep track of Tim’s photography on Flickr and Twitter.

Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.

A ‘Shallow’ Lunar Eclipse Coming on April 25

The very early partial phase of the 2010 December solstice total lunar eclipse. This week's shallow eclipse will appear similar at its maximum. (Photo by author)

Eclipse season is upon us this week with the first eclipse of 2013, a brief partial lunar eclipse.

The lunar eclipse on April 25, 2013 is a shallow one, meaning only a paltry 1.47% of the lunar limb will be immersed in the dark umbra or inner shadow of the Earth. Observers can expect to see only a dark diffuse edge of the inner shadow nick the the Moon as is grazes the umbra.

A partial lunar eclipse this shallow hasn’t occurred since May 3rd, 1958 (0.9%) and won’t be topped until September 28th, 2034 (1.4%). This is the second slightest partial lunar eclipse for this century.

Another term for this sort of alignment is known as a syzygy, a great triple-letter word score in Scrabble!

A video simulation of the eclipse:

The eclipse will be visible in its entirety from eastern Europe & Africa across the Middle East eastward to southeast Asia and western Australia. The eclipse will be visible at moonrise from South America to Western Europe and occurring at moonset for eastern Australia and the Far East. The partially eclipsed Moon will be directly overhead just off the northeastern coast of Madagascar. The eclipse will not be visible from North America.

Two eclipse seasons occur each year when the nodal points of the Moon’s orbit intersect the ecliptic while aligned with the position of the Sun and the Earth’s shadow. The Moon’s orbit is inclined 5.15° degrees with respect to the ecliptic, which traces out our own planet’s path around the Sun. If this intersection occurs near New or Full Moon, a solar or lunar eclipse occurs.

The visibility region of Thursday's partial lunar eclipse.
The visibility region of Thursday’s partial lunar eclipse (Credit: NASA/GSFC/F. Espenak).

If the Moon’s orbit was not inclined to our own, we’d get two eclipses per lunation, one solar and one lunar.

2013 has 5 eclipses, 3 lunar and 2 annular. The minimum number of eclipses that can occur in a calendar year is 4, and the maximum is 7, as will next occur in 2038.

The 3 lunar eclipses in 2013 are this week’s partial eclipse on April 25th and two faint penumbral eclipses, one on May 25th and another on October 18th. There is no total lunar eclipse in 2013. The last one occurred on December 10th 2011, and the next one won’t occur until April 15th 2014, favoring the Pacific Rim region.

This eclipse will also set us up for the first solar eclipse of 2013, an annular eclipse crossing NE Australia (in fact crossing the path of last year’s total eclipse near Cairns) and the south Pacific on May 10th. The only solar totality that will touch the surface of the Earth in 2013 is  the hybrid eclipse on November 3rd spanning Africa and the South Atlantic with a maximum totality of 1 minute & 40 seconds.

Contact times for the April 25 shallow eclipse:

P1-The Moon touches the penumbra-18:03:41 UT

U1-The Moon touches the umbra-19:54:04 UT

Mid-Eclipse-20:08:37.5 UT

U4 -The Moon quits the umbra-20:21:04 UT

P4-The Moon quits the penumbra- 22:11:23 UT

The length of the partial phase of the eclipse is exactly 27 minutes, and the length of the entire eclipse is 4 hours, 7 minutes and 42 seconds.

This particular eclipse is part of saros series 112 and is member 65 of 72.

This saros cycle began in 859 C.E. on May 20th and will end in 2139 on July 12th with a penumbral lunar eclipse. One famous member of this series was 52.  This eclipse was one of many used by Captain James Cook to fix his longitude at sea on December 4th 1778. Christopher Columbus also attempted this feat while voyaging to the New World. It’s a fun project that anyone can try!

I also remember watching the last eclipse in this series from South Korea on April 15th 1995, a slightly better partial of 11.14%.

An occultation of the bright star Spica occurs just 20 hours prior as seen from South Africa across the southern Atlantic. This the 5th in a series of 13 occultations of the star by the Moon in 2013.

Occultation of Spica
The visibility region for the April 25th occultation of Spica. (Created by the Author using Occult 4.1.0.2).

The +2.8th magnitude star Zubenelgenubi (Alpha Librae) is occulted by the waning gibbous Moon just 15 hours after the eclipse for Australia and the South Pacific.

Another occultation of a bright star with potential this week is +4.7th magnitude Chi Virginis across North America on the morning of Wednesday, April 24th  centered on 4:24 UT.

Chi Virginis occultation
Visibility region for the occultation of Chi Virginis on April 24th. (Created by the author using Occult 4.1.0.2 software).

Also keep an eye out for +0.1 magnitude Saturn near the Full Moon. Saturn reaches opposition this weekend for 2013 on April 28th

Full Moon occurs near mid-eclipse at 20:00 UT/16:00 EDT on April 25th. Colloquial names for the April Full Moon are the Pink, Fish, Sprouting Grass, Egg, Seed, & Waking Moon.

Sure, the penumbral phases of an eclipse are subtle and may not be noticeable to the naked eye… but it is possible to see the difference photographically.  Simply take a photo of the Moon before it enters the Earth’s penumbra, then take one during the penumbral phase and then another one after.  Be sure to keep the ISO/f-stop and shutter speed exactly the same throughout. Also, this project only works if the eclipsed Moon is high in the sky throughout the exposures, as the thick air low to the horizon will discolor the Moon as well. Compare the shots; do you see a difference?

A penumbral eclipse would offer a good proof of concept test for hunting for transiting exoplanets as well, although to our knowledge, no one has ever attempted this.

Finally, calling out to all Universe Today readers in Madagascar. YOU may just be able to catch a transit  of the International Space Station in front of the Moon just as the ragged edge of the umbra becomes apparent on the limb of the Moon. Check CALSky a day or so prior to the eclipse for a refined path… it would be an unforgettable pic!

The position of the ISS on April 25th at 19:48UT, just minutes before the partial pahse of the eclipse begins. (Credit: Orbitron).
The position of the ISS on April 25th at 19:48UT, just minutes before the partial phase of the eclipse begins. (Credit: Orbitron).

And if any ambitious observer is planning to live stream the eclipse, let us know and we’ll add your embed to this post. We do not expect an avalanche of web broadcasts, but hey, we’d definitely honor the effort!  Slooh is usually a pretty dependable site for live eclipse broadcasts, and as of this writing seems to have broadcast scheduled in the cue.

Happy eclipse-spotting!

Historic Comet Smashup Brought Water to Jupiter’s Stratosphere

Shoemaker-Levy 9 impact site G. The comet collided with Jupiter in 1994. Credit: R. Evans, J. Trauger, H. Hammel and the HST Comet Science Team

A large comet that peppered Jupiter two decades ago brought water into the giant planet’s atmosphere, according to new research from the Herschel space observatory.

Shoemaker-Levy 9 astounded astronomers worldwide when its 21 fragments hit Jupiter in June 1994. The event was predicted and observatories were trained on Jupiter as the impact occurred. The dark splotches the comet left behind were even visible in small telescopes. But apparently, those weren’t the only effects of the collision.

Herschel’s infrared camera revealed there is two to three times more water in the southern hemisphere of the planet, where the comet slammed into the atmosphere, than in the northern hemisphere. Further, the water is concentrated in high altitudes, around the various sites where Shoemaker-Levy 9 left its mark.

It is possible, researchers acknowledged, that water could have come from interplanetary dust striking Jupiter, almost like a “steady rain.” If this were the case, however, scientists expect the water would be evenly distributed and also would have filtered to lower altitudes. Jupiter’s icy moons were also in the wrong locations, researchers said, to have sent water towards the massive planet.

Internal water rising up was ruled out because it cannot penetrate the “cold trap” between Jupiter’s stratosphere and cloud deck, the researchers added.

“According to our models, as much as 95 percent of the water in the stratosphere is due to the comet impact,” said  Thibault Cavalié of the Astrophysical Laboratory of Bordeaux, in France, who led the research.

Eight impact sites from Comet Shoemaker-Levy 9 are visible in this 1994 image. Credit: Hubble Space Telescope
Eight impact sites from Comet Shoemaker-Levy 9 are visible in this 1994 image. Credit: Hubble Space Telescope

While researchers have suspected for years that Jupiter’s water came from the comet — ESA’s Infrared Space Observatory saw the water there years ago — these new observations provide more direct evidence of Shoemaker-Levy 9’s effect. The results were published in Astronomy and Astrophysics.

Herschel’s find provides more fodder for two missions that are scheduled for Jupiter observations in the coming few years. The first goal for NASA’s Juno spacecraft, which is en route and will arrive in 2016, is to figure out how much water is in Jupiter’s atmosphere.

Additionally, ESA’s Jupiter Icy moons Explorer (JUICE) mission is expected to launch in 2022. “It will map the distribution of Jupiter’s atmospheric ingredients in even greater detail,” ESA stated.

While ESA did not link the finding to how water came to be on Earth, some researchers believe that it was comets that delivered the liquid on to our planet early in Earth’s history. Others, however, say that it was outgassing from volcanic rocks that added water to the surface.

Conventional theory dictates ice was in our solar system from when it was formed, and today we know that many planets have water in some form. Last year, for example, water ice and organics were spotted at Mercury’s north pole.

Mars appeared to be full of water in the ancient past, as evidenced by a huge, underground trench recently discovered by scientists. There is frozen water at the Martian poles, and both the Curiosity and Spirit/Opportunity rover missions have found evidence of flowing water on the surface in the past.

The outer solar system also has its share of water, including in all four giant planets (Jupiter, Saturn, Uranus and Neptune) and (in ice form) on various moons. Even some exoplanets have water vapor in their atmospheres.

“All four giant planets in the outer solar system have water in their atmospheres, but there may be four different scenarios for how they got it,” added Cavalié. “For Jupiter, it is clear that Shoemaker-Levy 9 is by far the dominant source, even if other external sources may contribute also.”

Source: European Space Agency

Carnival of Space #298

This week’s Carnival of Space is hosted by Pamela Hoffman at the Everyday Spacer blog.

Click here to read Carnival of Space #298.

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.

3 Years of the Sun in 3 Minutes

This image is a composite of 25 separate images spanning the period of April 16, 2012, to April 15, 2013. It uses the SDO AIA wavelength of 171 angstroms and reveals the zones on the sun where active regions are most common during this part of the solar cycle. Credit: NASA/SDO/AIA/S. Wiessinger

Since the Solar Dynamics Observatory opened its multi-spectral eyes in space about three years ago, we’ve posted numerous videos and images from the mission, showing incredible views of our dynamic Sun. Scott Wiessinger from Goddard Space Flight Center’s Space Visualization Studio has put together great timelapse compilation of images from the past three years, as well as a one composite still image to “try to encapsulate a timelapse into one static graphic,” he told us via email. “I blended 25 stills from over the last year, and it’s interesting to see the bright bands of active regions.” Scott said he was fascinated by seeing the views of the Sun over a long range of time.

Within the video, (below) there are some great Easter egg hunts – things to see like partial eclipses, flares, comet Lovejoy, and the transit of Venus.

How many can you find?

SDO’s Atmospheric Imaging Assembly (AIA) captures a shot of the sun every 12 seconds in 10 different wavelengths, but the images shown here are based on a wavelength of 171 Angstroms, which is in the extreme ultraviolet range. It shows solar material at around 600,000 Kelvin. In this wavelength it is easy to see the Sun’s 25-day rotation as well as how solar activity has increased over three years as the Sun’s solar cycle has ramped up towards the peak of activity in its 11-year cycle.

You’ll also notice that during the course of the video, the Sun subtly increases and decreases in apparent size. This is because the distance between the SDO spacecraft and the Sun varies over time. The image is, however, remarkably consistent and stable despite the fact that SDO orbits the Earth at 6,876 miles per hour and the Earth orbits the sun at 67,062 miles per hour.

See more views, wavelengths and information at this page at the Space Visualization Studio website.

Chris Hadfield Explains Photography from Space

'A glance out the Space Station window is worth taking,' said ISS commander Chris Hadfield, of this image taken on Earth Day, April 22, 2013. Credit: NASA/CSA.

After Canadian astronaut Chris Hadfield arrived at the International Space Station in December 2012, he quickly became an internet sensation with all the tweets, Facebook and G+ posts he shared providing in inside look at living and working in space. But the biggest draw is all the incredible images he has shared throughout his ISS mission. In this video, Hadfield takes you to the best seat in the house – the Cupola on the ISS — to gaze at the visual splendor of the Earth. He shares his techniques and his passion for capturing the fleeting glimpses of our changing world.

UPDATE: NASA also chimed in for Earth Day with this video from astronaut Don Pettit sharing his images and tips for photography of Earth from space: