maravelias.info

Back in November of 2019, the primary mirror (of 1.3m) at the Skinakas Observatory was dismounted to send it for recoating (a procedure performed once every 4-5 years). The following short clip shows the packaging of the mirror, a very delicate procedure (the whole process took several hours … compressed to a few minutes).

Yesterday was the first night that I found myself at Skinakas Observatory. Even though some years have passed, there are really minor changes. The mountain welcomed us with great weather (scarce clouds, humidity close to 50%, and almost no wind at all!), while the seeing proved to be really good (~1″).

The 1.3m Skinakas telescope.

Trawling for transits in a sea of noise: A Search for Exoplanets by Analysis of WASP Optical Lightcurves and Follow-up (SEAWOLF)

E. Gaidos, D. R. Anderson, S. Lepine, K. D. Colon, G. Maravelias, N. Narita, E. Chang, J. Beyer, A. Fukui, J. D. Armstrong, A. Zezas, B. J. Fulton, A. W. Mann, R. G. West, F. Faedi

Studies of transiting Neptune-size planets orbiting close to nearby bright stars can inform theories of planet formation because mass and radius and therefore mean density can be accurately estimated and compared with interior models. The distribution of such planets with stellar mass and orbital period relative to their Jovian-mass counterparts can test scenarios of orbital migration, and whether “hot” (period < 10d) Neptunes evolved from “hot” Jupiters as a result of mass loss. We searched 1763 late K and early M dwarf stars for transiting Neptunes by analyzing photometry from the Wide Angle Search for Planets and obtaining high-precision (<10−3) follow-up photometry of stars with candidate transit signals. One star in our sample (GJ 436) hosts a previously reported hot Neptune. We identified 92 candidate signals among 80 other stars and carried out 148 observations of predicted candidate transits with 1-2 m telescopes. Data on 70 WASP signals rules out transits for 39 of them; 28 other signals are ambiguous and/or require more data. Three systems have transit-like events in follow-up photometry and we plan additional follow-up observations. On the basis of no confirmed detections in our survey, we place an upper limit of 10.25% on the occurrence of hot Neptunes around late K and early M dwarfs (95% confidence). A single confirmed detection would translate to an occurrence of 5.3±4.4%. The latter figure is similar to that from Doppler surveys, suggesting that GJ 436b may be the only transiting hot Neptune in our sample. Our analysis of Kepler data for similar but more distant late-type dwarfs yields an occurrence of 0.32±0.21%. Depending on which occurrence is applicable, we estimate that the Next Generation Transit Survey will discover either ~60 or ~1000 hot Neptunes around late K and early M-type dwarfs.

arXiv:1310.7586

A couple of experiments (with Manos Kardasis) on comets from Skinakas Observatory.

Comet 2010/S1

Comet 2011/F1

Comet 2011/F1

I was able to take a series of IR images from Skinakas telescope and Manos Kardasis did all the job with the processing. Here are the results:

Synchronized optical and IR observations of Jupiter.
Manos’ comments: “It is interesting though that even in oneshot – low resolution images – some bright SSTB ovals are visible. Also NNTZ LRS (L2 308, B 40.7) is bright. Another big bright spot a little northern (at NNTBn?) is visible at L2 218, B 39.”

Manos’ comments: “There are some white spots visible on NEBs with the H21 filter. GRS and oval BA are bright in all sets (except CO).”

In late August 2012 we (me and Manos Kardasis) tested the video capture method for planetary imaging using the 1.29m Skinakas‘ telescope. Although not aware of what problems to expect we finally didn’t encounter any (as Manos had been really working on this with great care and caution) but for the weather and seeing.
So, the test proved successful and all that is needed next time it good seeing.
Below you can see images of the equipment used and the results on Jupiter, Uranus and Neptune.
(Jupiter observations were also forwarded to Planetary Virtual Observatory & Laboratory / Jupiter section.)

Skinakas' 1.29m equipped for planetary imaging

Equipment: DMK/DBK video camera + barlow 2x (if needed) + filter wheel (L,R,G,B,Ch4,IR,UV) + eyepiece with flip mirror

Check Sinakas’ site for more details.

Location (latitude / longitude / altitude):
35 12 43 N 24 53 57 E     [in deg, min, sec]
35.2119 N 24.8992 E     [in deg]
1750m

Optical characteristics (scales/resolutions):

Telescope Limits
> At 1.4 airmass … open flap!
> At 2.4 airmass … change target!
[depending on the Dec – general values close to equator]

A great new book is available for the Crete Univesrity Press, Skinakas Observatory: A view at the Universe (language: Greek).

It is a photo tour around the Universe through magnificent images obtained from the 1.3m telescope of Skinakas Observatory.

Contents: Introduction / Skinakas Observatory: a short historical review / Skinakas: a great astronomical location / Coloured astronomical images / Solar system / Stars / Emission and reflection nebulae – dark nebulae / Planetary nebulae / Supernovae remnants / Open clusters / Globular clusters / Galaxies