Astrophotography by Anthony Ayiomamitis

Satellite Transit Gallery

I have a particular interest in satellite transits across the solar/lunar surfaces due to the opportunity they present the lucky observer to discern greater physical detail and structure as a result of their silhouette against the bright background of the sun and/or moon; the ability to restrict the satellite's location in the daytime or evening sky to an area measuring 0.5x0.5 with little or no effort; it permits for the bypassing of satellite tracking which itself is a challenge due the very short period transits are visible during a particular overhead pass; and the difficulty in obtaining accurate and timely orbital elements and TLE's. As this "search and identify" project has literally become a DAILY ritual, I expect this web page to be updated constantly with more and more images of the very unique phenomena of satellite transits across the solar and/or lunar disks.

Note: The capture of a solar transit by the International Space Station was an incessant chase for 3-4 years until July 28, 2005 when the ISS (with STS-114) was finally captured transiting against the Sun and which included the space shuttle Discovery. Approximately nine months later, the ISS was also caught transiting the rising moon (click here) albeit at a very low altitude.

The transit below involves the ISS and with the space shuttle Atlantis (STS-132) trailing by less than 23 seconds and one arc-degree. The primary purpose of STS-132 and its twelve-day mission was to deliver and install two main modules to the ISS, namely the Integrated Cargo Carrier and a Russian-built Mini Research Module (MRM-1) which is to be attached to the Zarya module. STS-132 represents Atlantis' eleventh and final flight to the ISS and is to be retired from the active fleet immediately thereafter. The sunspot below the ISS is AR1072.

Note: Following my successful capture of the ISS with the space shuttle Discovery (STS-114) transiting the sun on late July/2005 and which appeared on NASA's APOD (AstroPhoto of the Day, July 29, 2005), I received many requests for instructions in the identification and observation of similar opportunities and which are now fully documented here.

Note: Unfortunately the presence of high thin cirrus clouds adversely impacted the fine resolution which is normally possible otherwise.


Image Details
ISS Transits the Sun
Imaging Details
Satellite(s):
Int Space Station

USSPACECOM Cat No:
25544 (ISS)

Physical Dimensions:
73.0 x 44.5 x 27.5 m

Orbit / Inclination:
351.3 x 355.1 km, 51.6

Range (Image):
432.4 km

Angular Diameter:
42.8 " (ISS)

Pass Details (ISS):
Duration : 0.54 sec
Angular Vel : 56.1 ' / sec
Direction : 333.2
Azimuth : 105.6
Altitude : 52.0

Launch Date (UTC):
Nov   20, 1998   (ISS)
Date:
May 25, 2010
10:43:55 UT+3


Location:
Athens, Greece

Equipment:
AP 160 f/7.5 StarFire EDF
AP 2x Convertible Barlow
AP 1200GTO GEM
Canon EOS 5D Mark I
Baader UV/IR-Cut filter
Baader ND-5 (full-aperture)


Exposure(s):
1 x 1/2000 sec
ISO 800
RAW image format
4368x2912 image size
Continuous Servo Mode
Manual Mode


Software:
Photoshop CS2

Processing:
RAW to TIFF (16-bit conv)
Grayscale
Unsharp Masking
Brightness/Contrast
Levels
Resampling
Cropping
JPG Compression