August 7th, 2014

Star Walk HD got a Tabby Award

Star Walk HD – 5 Stars Astronomy Guide has been declared a Winner in the following category:

iPad: Education / Adults, professionals and general


The Tabby Awards, the only global competition for the best tablet apps and games, unveils the 2014 list of Tabby Awards winners, as well as the first Users’ Choice app list.

  Read the rest of this entry »

August 6th, 2014

67P/Churyumov-Gerasimenko Comet



Comet 67P/Churyumov-Gerasimenko by Rosetta’s OSIRIS narrow-angle camera on 3 August from a distance of 285 km. The image resolution is 5.3 metres/pixel.

Rosetta launched in 2004 arrives at comet 67P/Churyumov-Gerasimenko today. It is the first mission to rendezvous with a comet.

August 6th, 2014

Rosetta Meets the Comet Today


Later today, when the distance between the probe and the cometary nucleus will be 100 km, Rosetta will make trajectory corrections and start spinning around the “snow ball” with radius of 4 km. Formally, it is not called “orbiting” as the comet’s gravitation is not enough for Rosetta. The probe will fly in front of the comet to avoid the damage from dust of its tail. 

The engine will be firing for 6 minutes 26 seconds and will start at 08:00 GMT.

The distance to the probe will account for the 22 minutes delay in data transmitting. Because of the difficulties in data transmission we won’t be able to see the video of approaching, but we will be able to see the photos from the navigational camera as soon as it is possible.

Here is the video prepared by ESA demonstrating the fly-over of Rosetta around the comet:

This is the latest model of the nucleus built from the pictures made in July.

You can see the live streaming of the event on the ESA site.

In 4 months there will be another key event – the landing of Philae.

August 6th, 2014

Rosetta – the Cometary Nucleus is Near

Rosetta is nearing the culmination of years of cosmic expedition. This fall, a unique spacecraft Philae will land on the comet’s nucleus 67P / Churyumov-Gerasimenko, and meanwhile Rosetta is approaching the comet and has already transmitted intriguing scientific information.


The comet Churyumov-Gerasimenko was discovered in 1969 by Soviet scientists Klim Churyumov and Svetlana Gerasimenko. It is classified as a short-period comet, meaning that it does not fly away into the depths of the Oort Cloud to the outskirts of the solar system, but travels only a little farther than the orbit of Jupiter. Every 6.6 years it is moving closer to the Sun, but not enough to evaporate, like ISON. 67P does not get even as close as the Earth’s orbit.


Comet Churyumov-Gerasimenko was selected by the European Space Agency (ESA) for a thorough exploration by probe Rosetta with lander Philae. This choice happened partly by accident.  Originally, the scientists planned to study the comet Wirtanen, but had to postpone the launch of Rosetta due to a faulty rocket Arian-5. When the problem with the rocket was solved, they decided comet that Churyumov-Gerasimenko was the most opportune.

The peculiarity of Rosetta mission is that previously all research stations studied comets on a collision trajectories and close rendezvous ended in a matter of hours or minutes.


Currently Rosetta is catching up to the comet and in August will be on its orbit (or rather will just rotate close by).


As it turned out, the unexpected hitch with the launch vehicle gave the scientists a chance to conduct an even more complex and fruitful research than they expected. The comet has tossed a few surprises that no one expected.


Now the comet comes closer to the Sun, so when in April its gas-dust coma began to grow no one was surprised. But in May, the growth of the coma stopped, and in June it was back to the shape of an almost bare piece of rock and ice.




In June, NASA scientists used one of their three instruments, placed on Rosetta in agreement with their European counterparts, to estimate amounts of water vapor emitted by the comet. The emission was about 300 milliliters of water per second. For they three-mile “snowball” this result seems rather modest, although almost 26 tons per day – sounds more impressively.


In June we began to receive the first pictures in which the nucleus of the comet began to occupy more than one pixel. Previously, the form of the comet was modeled on the basis of the images from the Hubble telescope, and for a long time this data was the most accurate. ESA has prepared a lot of illustrations the images obtained by Hubble.



On June 28, when the distance to 67P was 86 thousand kilometers, the scientists were able to obtain a series of images allowing to see the rotation of the nucleus.



But it took another half of this distance to begin to discern its shape. On July 4 the distance to the comet was 37 thousand kilometers and the new images showed that the comet is different from what we expected.



On July 14 from a distance of 12 thousand kilometers  we opened a new sensational detail: Comet 67P / Churyumov-Gerasimenko seems to have two cores! 


Nothing like this has ever been observed. Earth probes have already encountered asteroids stuck together, such as Itokawa, but not a comet. This could be the result of the collapse of a larger nucleus when the comet disintegrated from the heat and then the fragments were joined together again by the forces of gravity. But it may be that 67P / Churyumov-Gerasimenko – is the result of the meeting of two different cometary nuclei. We will be able to tell by analyzing their structure and the nature of gas and dust emissions. If it turns out to be the second option, it will open up a unique opportunity for scientists to study two comets at once. They could not dream of such a gift from the solar system.



Wags have already compared the shape of the comet’s nucleus to a toy duck, and suggested that one part should be called “Churyumov” and the second “Gerasimenko.”


Now Rosetta is approaching the comet at a speed of about 2 thousand kilometers per day, so every day we receive more accurate and detailed pictures. Today, the distance from the probe to 67P should be about 4-5 thousand km, and the surface details must already be visible.


The trouble is that the ESA scientists don’t generally publish all pictures as they become available, as does NASA, for example, with frames from Curiosity. First, the Europeans want to write articles, monographs and dissertations, and only then are ready to share the results of Rosetta with the world. As a result of this policy, a detailed survey of the comet will have to wait 6 months to a year, and for now we will have to do with the content that publishes ESA after coordination between all research groups.


We’re now watching the developments.

via Zelenyikot

July 25th, 2014

Fifth Annual Star Walk Month of Astronomy Starts Today

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Summer nights are great for all kinds of outdoors activities and being the stargazing geeks that we are, we just have to share our obsession with the night sky.  We are excited to announce the beginning of the fifth annual Star Walk Month of Astronomy. Every year we choose the most eventful month in terms of things to watch in the sky and share all plans and discoveries with 10 million Star Walk fans all over the world. Get some friends, take some photos, win an iPod touch and more!

July 25 – August 8

For two weeks we will hold Astrophotography Contest (here’re few tips on how to make astro photos) on Star Walk Facebook page. If you want to take part:

- Post your astrophotography work on Star Walk FB page from July 25 to August 6

- Add #SWMonthofAstronomy in the description

- Stay tuned, as there will be two winners (the winner of the 1st week and the final one)

Prizes: the winner of the 1st week gets a place in the Star Walk app Gallery, the final winner also gets a place in the Gallery and a $60 promotion on SW FB page.

August 8 – August 22

Don’t miss your chance to win an iPod touch 16 GB in the Month of Astronomy Giveaway. More details about the giveaway you will find in August on Star Walk FB page.

And here is what the sky will show during the Month of Astronomy.

July 30

Two meteor showers will peak – Alpha Capricornids and the Southern Delta Aquariids

August 11

The closest full moon of the year – the Super Moon

August 13

Perseids meteor shower peak

August 18

Kappa Cygnids meteor shower peak

How to watch the events?

All the astronomy events mentioned above can be easily found in Star Walk app.

Users of Star Walk app on iOS:

Tap on the Menu button in the lower right corner of the screen and open the Calendar. If you tap on the event in the Calendar, the app will guide you to the center of the show in the sky. Clock icon in the Calendar sets the notification so you won’t  miss the event.

Users of Star Walk app on Android, Windows, Kindle:

Tap on the Search icon in the lower right corner of the screen, then type the name of the object you are looking for in the search line. Choose the object, activate your Star Spotter by tilting your device, and  let the green arrow show you  the way.