Here at Starmap, the loss of dark skies is a real concern. In the team, we are all astronomers, some spending hours observing stars in their backyards, some from the largest telescopes in the world.

We have lost good quality skies … we all have, not only star gazers.

We are glad to announce the release of  Losing the Dark, a film produced by the International Dark Skies Association and Loch Ness Productions, and made possible by all of you who spent some dollars or euros buying our app.

This film is now available for all planetariums and star domes, for free, all over the world.

This is the best way we found to reward our numerous users, all around the world … trying to bring them back dark skies !

The near-Earth asteroid 2012 DA14 will pass very close to our planet on the 15th of February.

This film shows how the asteroid is displayed in Starmap and its path in the night sky.

You can display the exact position of the asteroid in Starmap as soon as you have updated the catalogue on your device.

How to update the catalogue:

• Go to the Solar System settings
• Select “Asteroids”
• Update the catalogue, up to the Main Belt.
• Then in the catalogue search, look for “2012 DA14″
• Just add it to your favorite objects to avoid searching each time.

With one touch, Starmap users may discover in a single list all planets, meteor showers, stars, constellations and deep sky objects that can be observed at their location. This unique functionality is now enhanced with even more objects and filter options. A great help for beginners as well as for advanced night sky observers.

How it works.

	In Starmap, simply touch the icon Tonight from the bottom menu bar.
	Starmap PRO users will have access to the function in the Find section.
	iPad users will find the function in the bottom menu bar.

	Right away, Starmap computes the list of the celestial objects that can be seen tonight, for your exact GPS location and time of observation.The list includes: • planets • main stars • active shooting star regions • deep sky objects like nebulas and galaxies • remarkable double stars • constellations Given the large number of celestial objects in Starmap databases, the lists can be collapsed or filtered at your convenience. You can sort it easily by luminosity or by rise time.
	As the sky moves along the night due to the Earth rotation, celestial objects will not be visible all night long. Use the time slider or one of the presets for setting your exact period of observation.
	Starmap is a scientific tool made for casual star gazers  and advanced astronomers. Select your means of observation. Starmap will select the objects most suitable for you, from the most accessible for unaided eyed observation to the faintest objects that can only be observed through larger telescopes.

What’s behind.

Starmap computes instantly the position of about one thousand celestial bodies in less than 100 milliseconds on an iPhone 4. This does not only consist of single position in the sky but full trajectories over the time. The algorithm uses pre-computed time series and assemble them according to the user location and time of observation. Only objects located above a 15° imaginary horizon will be kept. Under this limit, the atmosphere generally hinders the observation.

This is a good example of how increased processing power in handheld devices provides new services to users, hidden behind a simple touch.
The same technique has been used for comets in Starmap. In the PRO and HD versions, the user has access to the list of comets sorted by identifiers but also by magnitude — meaning their luminosity. This implies the computation of 900 know comets, including their present position in space, their distance and their intensities, taking into account their albedo — a sort of whiteness factor.

This calculation is performed within 100 ms on a 3GS iPhone, and in 30ms on a iPhone 4.

For a programmer like me,  it is sometimes frustrating to encapsulate so many hours of work and optimized computing into a single touch. This makes the user’s life easier of course, and it is the purpose. With this post, I just wanted to spotlight that what appears as most natural requires generally a huge amount of work… especially for an application like Starmap. This makes the difference with other gadget planetarium applications :-)

 The sexy equations behinds Starmap … what users should never see …

(Re)Discover the Ring Nebula

The Ring Nebula is one of the most famous celestial object that can be seen from the northern hemisphere. The film is a journey inside the Nebula, showing its formation and its real shape. The Ring Nebula is not a ring … but an oblate spheroid.

The 3D model used in the film as based on scientific data. It is as close to reality as possible.

The white dwarf formation

90% of the stars in our universe will become white dwarves, including our Sun. The transition will occur in about 100 million years, passing through the state of red giant.

The planetary nebula is a transient object in terms of astronomical time scales. If the life time of the star would be compared to a year, the red giant transformation would occur on the 27th of December. The planetary nebula created in the transformation into a white dwarf would exist in the last 100 milliseconds.

A star life cycle depends on its size. This is balance between the internal pressure due to the gravity and the energy emitted by nuclear reactions. Hydrogen will be converted to heavier elements, like helium, then carbon or oxygen. All heavier atoms, like these in our body, have been created by nuclear reactions in stars.

By creating heavier elements, the star density increases. At one point, the internal balance between the gravitational pressure and the temperature is lost. The nucleus collapses. This could be compared to bones no more able to support a body becoming too heavy.

In the case of the white dwarf, the core collapses. The shockwaves repel the outer stellar matter in space, creating a planetary nebula.

The nebula will finally diffuse in space, taking away these heavier atoms. This gas will later be captured by more dense space regions, and merged to diffuse nebulae. These stellar nurseries will give birth to new stars. The proto-planetary dust ring around the new born stars contains these atoms, and later on, the planets. This completes the cycle.

The Nebula shape

As said in the film, the Ring Nebula is not a ring … but an oblate spheroid. This scientific article describes the process behind in all details (Three-Dimensional Ionization Structure and Evolution of NGC 6720, The Ring Nebula”. Astronomical Journal 134 (4): 1679–1692).

Compared to other planetary nebulae, the shape of Ring Nebula is very  “simple”. An excellent summary of complex planetary nebulae shape can be found here.

In a simplified very way, the shape is influenced by three factors:
First, the initial impulse provided by the stellar core collapse is not always homogenous in space. The star plasma fluxes is very complex. Temperature and pressure have a spherical symmetry, but magnetic fields, by essence do not — they conform more to a torus topology. As the star plasma is highly magnetic, and also the source of the magnetic field, the plasma fluxes have highly complex structures, far from being spherical. The arches of matter of some nebulae results from these initial magnetic field lines. Then, once the matter has been repelled into space, it will be influenced by the stellar wind emitted by the central star. Finally, the corona can locally gather into clumps, due to the gravity. This is the case for the Ring or the Dumbell Nebulae.
Other factors, like the presence of planets or of a star companion will also influence the final shape.

Starmap è l’applicazione perfetta per osservare l’universo attraverso mappe realistiche e dati ben dettagliati. Basata sulla tecnologia di geolocalizzazione con bussola per iPhone, Starmap Pro indica con esattezza la precisa posizione dell’utente e permette di visualizzare il cielo in tempo reale, ingrandendo e riducendo gli oggetti celesti come si desidera. Starmap dispone di molte altre funzioni per potenziare l’esperienza di osservazione dello spazio, tra cui informazioni e immagini di oggetti celesti, dati sull’osservazione del cielo specifici per la propria zona ed altro ancora. Questa applicazione è perfetta per l’appassionato novello così come per l’astronomo professionista. Starmap Pro è disponibile in iTunes per iPhone, iPad e iTouch.

Mankind follows a similar path. As I began my studies, some thirty years ago, the possibility of extrasolar planets was only mentioned by my professors with an ironic grin from ear to ear. Today, hundreds of such planets have been observed beyond our Solar System. An article published in Nature in January 2012 now proposes the existence of billions of Earth-like planets in our galaxy. Thirty years ago, life in Universe was considered as a unique event. And now, what about extraterrestrial civilizations? I dream of living long enough to be present for this revelation.

As mankind grows up, we become smaller and smaller.

Throughout time, we have reassured ourselves with stories and models placing us at the center of the Universe, like Ptolemy’s model.

The story of Galileo and his tenacity to prove the Earth was revolving around the Sun is a key moment in the history of science. For centuries, the Church had accepted once and for all Ptolemy’s model, because it was placing the human being at the center of the creation.

Ptolemy’s approach, however, was not religious, but logical. His theory was explaining well enough the positions of planets and predicting the time of eclipses. The observation means of these times were simple geometrical landmarks for visual observations. Stonehenge must have had a similar purpose.

The real shock caused by Galileo was the confrontation between the tangible reality revealed by his telescope, contradicting the geocentric model of the Church. He had in plain view Jupiter and its satellites, understood as a reduced version of the Solar System. He could observe the phases of Venus and could only explain them by placing the planet around the Sun. Giordano Bruno, some years earlier had been burned for having upheld such ideas. But his approach was philosophical and not supported by observation. The future Pope Urban VIII had looked through Galileo’s telescope years before the trial he conducted against his friend.

Seeing and understanding, without believing, admitting that every model is wrong by essence … this is what we scientists learn on the benches of Universities. That’s sometimes a hard concept to grasp!

As the first images sent by the Hubble telescope came to our eyes, I remember some astronomers just denying them as they were not in accordance with the standard model of the time, which is now obsolete.

Today, the Earth is still flat.

Of course, we know it’s round in shape since we saw it with our own eyes as we stood on the Moon. What I mean by the Earth is flat, is that our perception of the shape of the Universe and of its evolution is as erroneous as pretending the Earth is flat. We know today that we cannot directly observe most of the matter composing our Universe, the dark matter. We know that our Universe is expanding, and that, counter to our physical laws, this expansion is accelerating. We have no idea of its shape or structure. Just plain hypothesis.

Since the large success of Starmap, I have been contacted by many users. Very modestly, among many others, my application has given them occasion to look at the stars and ask themselves some questions. Through the forthcoming articles, I will attempt to provide them with some keys, not for explaining our Universe, but to let them understand why we explain it the way we do.

Rephrasing a french saying … if you look for certainties, grow turnips, don’t look at the stars.

Some dates and milestones

As I was testing the new Moon map of Starmap in real conditions, I’ve been surprised by how much there is to see there. Its geology and its formation are well illustrated by some of its surface structures, easily observable, even with binoculars. The spokes around the crater Tycho, sometimes as long as 1500 km, are amazing witness of catastrophic collisions. Seas and Oceans — or Mare — are ancient lava pools. But my favorite is certainly the Great Wall (Rupes Recta). Imagine a 100 long cliff, 300 meters high, and perfectly straight.

My point here is not to talk about the Moon formation, but how to use Starmap to re-discover it. Travelling on the lunar surface with a telescope and a paper map is not so easy. So, enter your optics configuration in Starmap and switch to the eye piece mode. Some optics are inverting the image, making the spotting even more difficult. Just swipe your finger vertically or horizontally to have Starmap exactly display what you see in real.

When you observe the Moon, the bottom menu will change. Beside the Moon catalogue, you will find the Moon Brightness slider. Adjust the brightness and contrast so that it reflects what you see in your eye-piece. I added this function after the first tests as the map was too bright for large magnifications, making any identification almost impossible. Matching the map to the real observation conditions is the key to successful observations. Then search for Rupes Recta in the catalogue and simply follow the yellow arrow.

Moon structures are best observed at the limit between light and shadow, at grazing incidence of light. Using the frontier as a start point, spotting a well identifiable structure helps a lot to know where you are — especially when changing your eye piece. The Moon Image in Starmap is a compound of many images taken near the light/shadow limit. So do not be surprised that when going away from the shadow, the contrast will decrease, compared to what Starmap shows you.

Try the map. This is an invitation to rediscover the Moon, and you will be amazed by how much you can see there !

PS: I am presently working on Moon librations for future releases.

Difficult answer, heavy responsibility…

My first recommendation would be: go for quality. I tried some cheap telescope (about 80$)  a friend of mine purchased on eBay and this was a real nightmare. Cheap and unstable mounts make observations a painful experience and give the false impression to beginners that observing is difficult… well … it can be difficult, but it should not be because of stability !

If your budget is limited to 100$, I would say, buy some nice binoculars and a stable tripod. You will see a lot already. If astronomy is not your thing after all, the binoculars will always serve for other purposes.

According to my experience, a good telescope for beginners,  is a Newton, with a focal length of  about 90 cm and an aperture of 10cm (the famous 114/900 type …). Its optics is simple and easy to tune. It will offer enough light to see many deep sky objects like galaxies or planetary nebulae. You will not be limited so fast.

As for the mount, I would choose an equatorial one. At first, beginners might feel a little disoriented as its axis of rotation should be aligned with the North (or South) pole. Be relaxed on this matter. It took me two hours to exactly align my telescope on Polaris the first time … but this was for astro-photography. If you want to observe Saturn for instance, just set the axis about to north, pointing about to Polaris. This will be sufficient ! I had my first Newton with twelve … so believe me, I know what observing with a badly aligned telescope means. And after all, finding Polaris and understanding the Earth rotation is part of the fun. And once aligned, even roughly , following a planet or the Moon for few minutes will be much easier as this only implies turning one axis wheel.

And what about auto alignment, motors, etc … ? Well, not everyone will agree with me, but I take the risk of a statement. I never saw any automatic alignment hardware working reliably and repeatedly. I have seen too many beginners being disappointed. So my message is “pointing by hand is the best way to learn the stars !”. Keep motors for astro-photography only and put your money into quality optics and mechanics rather than in what I consider as a gadget for beginners.

Finally, before buying your first telescope, why not attending to a star-gazing party ? There are astronomy clubs everywhere and getting your hands on a real telescope might be the best way to go further after all …

2005YU55 is an asteroid that will fly closer to the Earth than the moon in the next few days, a so-called NEO (Near-Earth-Object) [USA-today].

According to USA Today, the asteroid is scheduled to fly between the Earth and the moon’s orbit Tuesday, Nov. 8. Such events are fortunately very rare. We expect the next object to be flying this close to us not to arrive until sometime in 2028.

The good news for Starmap and Spacemap users is that it is viewable in both of these applications, and Spacemap is the only iPad app to show the 2005 YU55′s orbit in 3D animation.

Starmap, a leader in astronomy applications, publishes this information on our iPhone and iPad apps.

Here is how to access it:
As Starmap catalogues contain 470,000 asteroids, these are not delivered by default with the application. However, updating the catalogue is quite easy. Go  the Settings, select Solar System, Asteroids, and select the package Main Belt. The Main Belt is a region between Mars and Jupiter occupied by  700,000 to 1.7 million asteroids. Not all of them are known of course.

Once Starmap has uploaded the asteroid package, go to the Search function, and look for 2005YU55.

[update, many users are downloading the asteroid catalogue  and there is a lot of traffic right now. In case of time-out, simply try again].

Astronomers are permanently surveying these objects. As you might notice in Spacemap, the asteroid is not flying really close to Earth when zooming. The truth is that the trajectories of such objects are quite erratic and our knowledge only of their paths is only partial. The average precision is the Moon-Earth distance. So when an object flies close the Moon orbit, it is very carefully monitored by Scientists.

For more scientific information, check the Minor Planet Center, NASA and Wikipedia.

Spacemap accompagna l’utente in un viaggio fra le stelle, oltre il sistema solare, fino ai confini estremi dell’Universo conosciuto. Animazioni ed effetti sonori fantastici… abbinati a precisione scientifica. Le orbite di tutti i pianeti, le comete e gli asteroidi conosciuti sono rappresentati con la massima risoluzione. 25.000 oggetti, come galassie o stelle, possono essere individuati in questo modello tridimensionale dell’Universo. Comprende anche i pianeti extraterrestri e gli oggetti che possono entrare in collisione con la Terra.