This morning in Brasil, a large part of Africa, Turkey and Russia was been visible a total solar eclipse. When a total eclipse occurs, there are some zone on earth (like Rome, exactly) where the solar eclipse is partial. This picture was captured during this partial phase of the eclipse on the flat roof of the phisics’ building at the University ‘La Sapienza’ with some friends of mine.

To realize this picture I used a orange solar filter, a tripod and I set the ISO speed to 400, a time exposure of 1/80 seconds and f/4,9.

This experience has remembered to me, with a lot of wistfulness, the total eclipse of 11 August, 1999 I saw in Hungary.

I observed, with my friend Costantino Sigismondi and his students, the occultation of BY Cancri by Saturn and its rings on 2006 January 25. This star is a delta Scuti variable with a very small amplitude, is catalogued as HIP 42705 or SAO 98054 and its brightness is 7.91-7.92 mag. This star belongs to M44, also called Praesepe cluster (Latin for “manger”).
I have shot some picture of Saturn like this:

thanks of Costantino’s reflector telescope and realized with a time exposure of 1/10 seconds at 400 ISO and f/4.9.
Later, with a longer time exposure (1 second at 400 ISO and f/2,8), I’ve captured the image of 3 Saturn’s satellites and of 2 star of the Praesepe cluster, including BY Cancri, labelled with its SAO number, barely visible out of Saturn disk:

Of course the elongated shape of Saturn and the line-like stars are due to the Earth rotation and, consequently, to the rotation of the celestial sphere.
For further infomation on this occultation, I suggest to visite the IOTA page on this event.

In occasion of the asteroidal occultation of Rhodope over Regulus, on 19 Octorber 2005 (visible in a narrowed stripe along Europe), I shot this picture from Vibo Valentia (Calabria, Italy) of Lion costellation, with an exposure timing of 15 seconds:

Note that, although it was partially clouded, are visible all main Lion’s stars:

For a description of this astronomical event see “Occultazione asteroidale: Regulus vs. Rhodope” (in italian language), my article (with Costantino Sigismondi, in english) or the IOTA site.

I like to observe the moon not only for scientific interest, but chiefly because she (the moon) is there, and she’s beautiful.
Ok, I confess it: the first reason is that I like cheese… but you don’t say it to nobody, please! Anyway, today I have taken my 16×70mm binoculars, I fixed it on a tripod, and I shot a picture of the moon… easy, isn’t it?

Technical informations about this photo are: an exposure of 1/500 seconds (to attenuate the camera vibration), f/4,9 and ISO-400 (to compensate the speedy exposure), super macro mode (for a good focusing of the ocular).

When only a quarter of our natural satellite is visible (a bit more than first quarter in the picture), I think the moon is more photogenic, because solar light collides obliquely the moon surface, and that give more definition to the lunar formations as craters and seas. Moreover, when one can see the full moon, the moon appear as a flat disc and not as a sphere which she is (the best spherical appearance is during a lunar eclipse).

Now, what are the visible lunar formations? Here a little moon atlas

I labelled some craters and seas and marked with a dot the place where Apollo 11 landed, that is in an area known as ‘Mare Tranquillitas’ or ‘Sea of Tranquillity’. ‘Mare’, is the Latin for ‘Sea’, these seas were named so because early astronomers believed the black patches were indeed land locked seas.

I used the Virtual Moon Atlas free software to make me sure that all lunar formation names was correct.

This afternoon I’ve taken 30/30 in Astronomy’s exam. To celebrate this I publish a portion of the blackboard of an University room when, exactly 2 weeks ago, I lectured on tensorial formalism in relativistic electrodynamics…
Note the gauge transformation and the power of electromagnetic tensor that show how electric and magnetic fields are a single physical object.

These occasional lectures of mine are intended as a complement to Prof. Remo Ruffini’s class on theoretical physics (he is a scientist that is like a mentor to me).

Technically this photo is taken in a room but without flash with an exposure of 1/3 seconds and ISO-50. After shooting I’ve erased all blue dominance (probably due to sky’s light coming from the window) by turning on black-white the color method since the only relevant colors are black (the blackboard) and white (the chalk).

Rome isn’t a good place to see the sky by night because of the light pollution, but anyway with a digital camera one can realize satisfactory photos… like this!

That’s a portion of sky showing the Ursa Maior constellation, commonly called Great Bear. This is a constellation of the northern hemisphere; in central europe this constellation never touches the horizon.

Technical details: data 7/2/2005 22.30; focal lenght 6mm; F/2,8; exposure 15 sec; IS0-400. After shooting: light-darkness balance.

The following is the drowing of the UMa constellation. In reality, this is only the most famous asterism (subset of a constellation) called Big Dipper (others asterisms).

Finally, the following figure is a blowup of the Mizar-Alcor system. Note the presence of a blue coma and a lengthened shape due to the exposure of 15 seconds: between the opening and closing stars are moved on the celestial sphere. Different technical details for this picture: focal distance 17mm; F/4,9.

Now, some astronomical and astrophisical details:

from Munich Astro Archive