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Night object - Saturn?

  1. May 17, 2014 #1
    Hi all!

    I took a couple of pictures of the Moon at night on 16 May (with an Olympus VR-340 compact digital camera, 10x optical zoom, 4x digital zoom). I used a very small tripod mounted on a microphone stand :biggrin:, and I decided to try out the camera on a star just for fun. First I tried on a reasonably bright star, but I did not manage to zoom in on it, since I had a terrible mount and only the camera screen as a finder.

    I then decided to try on another star, and I had better luck zooming in on it. To my surprise it became larger than I expected, and at first I thought it was some kind of optical bug. I then took a couple of pictures of the object, and then I thought that maybe I had captured a planet...

    Here are a couple of photos of the object (5 originals and 5 adjusted with autolevels):

    14180605886_4b229dc4cc_c.jpg

    (other photo sizes here)

    I'm a complete novice at these things, and I am terrible at locating objects in the sky, so I checked with this online virtual telecope: http://www.fourmilab.ch/yoursky/#Telescope

    My location was

    Location: Malmö, South Sweden
    Coordinates: 55° N, 13° E
    Observation direction: Southwest
    Date/Time: 16 May 2014, 01:48 AM (CET, UTC+01:00)

    Photo of observation location, directed at the object, looking southwest:

    14017141277_ee2f858d86.jpg

    I entered my location info into the virtual telescope above, which yielded this view:

    14200500771_d811e671bc_z.jpg

    (here's the page with my info entered into virtual telescope)

    According to the virtual telescope, Saturn was approximately located in this direction. I am however not experienced enough to know if it is Saturn or not, so, what do you experienced fellows think, could the object in my photos above be Saturn?

    Side note 1: By the way, here are some pictures of the Moon I took on that night
    (as a filter I used two sunglasses mounted in front of the camera lens).


    Side note 2: I will buy a telescope pretty soon, but I haven't yet decided which one. I've also read the entire telescope thread here on the forum, and thanks to all contributors!
     
    Last edited: May 17, 2014
  2. jcsd
  3. May 17, 2014 #2

    adjacent

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    If that is Saturn, where are the rings?
     
  4. May 17, 2014 #3
    I have no idea :biggrin:. I am a complete novice. I thought that maybe the color of the object would help experts to decide if it could be Saturn or not.
     
  5. May 17, 2014 #4

    russ_watters

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    Can you estimate the direction better? Saturn was SSW at 17 degrees altitude at the time, but Mars was WSW at 15 degrees altitude. I think it is more likely that it's Mars (that was my first thought when I saw it too).

    Almost directly between them and slightly dimmer than Saturn (Mars is brighter than Saturn) is the star Spica. Above that a good fraction of the sky is the star Arcturus, which is about as bright as Mars. See below:


    attachment.php?attachmentid=69851&d=1400335622.jpg
     

    Attached Files:

    Last edited: May 17, 2014
  6. May 17, 2014 #5
    Thanks a lot, Russ! I've also had second thoughts since I posted, thinking if it might be Mars instead. Good idea about the direction! I will go out on my balcony (where the picture was taken) with a compass in a while, I think I can get a better estimation. The weather is very nice at the moment over here, and hopefully it will be a clear night. If it is, I will go out tonight and try to repeat the observation. I'll also give it a try with my cheap binoculars.
     
  7. May 17, 2014 #6
    Ok, I did an estimation of the observation direction with my compass and with the help of my balcony photo above. My compass says 245 degrees, and that is pretty much WSW according to this compass card. I had to check with the compass card, it was a long time since I used a compass :smile:.

    EDIT: I will try to make a simple sextant for an altitude estimation tonight. I hope for clear skies...
     
    Last edited: May 17, 2014
  8. May 17, 2014 #7
    A program you can use to help you learn the stars and objects in your local night sky is Stellarium. It's free on the computer, and I believe Android based devices, but iOS costs a few dollars. It's pretty amazing actually
     
  9. May 18, 2014 #8

    davenn

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    that could easily be ( and I highly suspect it is) just an out of focus image of a star or planet
    you are not going to get Saturn that big with only a 10x zoom ( digital zoom on any camera is next to useless, produces too much image distortion)

    Even 1000mm focal length telephoto lens on my DSLR camera only produces a tiny image for Jupiter or Saturn

    You would have much better success putting your camera up to a telescope where the eyepiece would normally go and doing some careful focussing ... you will be much more likely to get a useable and identifiable image

    cheers
    Dave
     
    Last edited: May 18, 2014
  10. May 18, 2014 #9

    davenn

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    Yes it is a great program ... I recommend it often here on this and other forums :smile:

    Dave
     
  11. May 18, 2014 #10
    Hi again everybody and thanks for all the replies!

    I just pop in to say I managed to repeat the observation last night, along with a measurement of azimuth and altitude, incl. changes of those variables during the observation time.

    Thanks! I've downloaded and tried Stellarium briefly - it seems good, I get it. I will try to upload new photos and do a comparison with Stellarium tomorrow, so I'll be back with the results here then. Thanks again!

    Thanks. That thought came to my mind when I did my second observation last night. At the moment I think it is Mars, but I'll be back tomorrow with my calculations, comparisons and new photos.

    Totally agreed :smile:. I almost never use it myself.

    Thanks, that's good to know.

    Completely understood. Hopefully I will select and buy a telescope sometime this year. Actually I had planned to own one already, but I actually haven't dared to yet :smile: - I have some other hobbies with projects to complete first, and if I bought a scope now, I would very likely start spending too much time with it, hehe. I want to finish my other projects first, so I'm actively delaying my gratification :biggrin:.
     
    Last edited: May 18, 2014
  12. May 18, 2014 #11

    davenn

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    Probably not Mars, not red enough

    You need to understand that the disc you are seeing is NOT the disc of a planet
    its just the out of focus image of a pinpoint of light


    Dave
     
  13. May 19, 2014 #12
    Hi again!

    I'm back with new photos and calculations from my second observation, and a comparison with Stellarium. First, please note there is an unfortunate error in my second photo in post 1: the date was not 17 May, but 16 May. Sorry for that.

    Ok. It was just a quick (and likely wrong, see below) guess I did from briefly checking the position with Stellarium in post #10.

    I did understand that :smile:. That was actually what I meant when I wrote "That thought came to my mind when I did my second observation last night" in post #10.

    ----------------------------------------------------------------------------------------------
    Ok, here are the photos from my second observation on 18 May 2014 between ca 01:44 and 02:00 CET (UTC+1:00).

    Photos of the object:
    14040214150_1afcf6d2db_c.jpg

    Observation location (the object can be seen in the sky in the center of the images)
    The building to the left is the Malmö Opera and Music Theatre. Note that I am aware that this location is not very good, but I was racing against the clock and I did not want to go into any dark park alone at this time.
    14223524611_c650c4d560_o.jpg

    Two other photos of the location are here: 1, 2.

    I drew two lines with a pen on my crappy sextant to mark the two altitude measurements. Altitude 1 = altitude at 01:43, ca 10 degrees, Altitude 2 = altitude at 02:01, ca 7 degrees. The thing that is taped to the sextant is a plastic drinking straw, which I was looking through in order to direct it to the object.
    14203688096_8a6b2331f8_o.jpg

    Regretfully, my sextant was positioned on a nonhorizontal surface, so I had to make corrections to my altitude measurements (the box on which I placed my gear was a metal cabinet, so I did not do my compass measurements close to it):
    14040820657_91130c84f6_b.jpg

    Here's a photo of my gear (tripod, compass and a crappy improvised sextant).

    ------------------------------------------------------------

    My second observation & measurements

    Date: 18 May 2014
    Time: 01:44 - 02:00 CET (UTC+1:00)

    Object visibility: Easily visible to the unaided eye.
    Object color: Somewhere between yellow & brown (according to my unaided eyes and my view in binoculars).

    Object measurements at 01:43 (ca)
    Azimuth: 225 degrees
    Altitude measured: 10 degrees
    Altitude offset: 3 degrees
    Altitude calculated: 10 + 3 degrees = 13 degrees

    Object measurements at 02:01 (ca)
    Azimuth: 230 degrees
    Altitude measured: 7 degrees
    Altitude offset: 3 degrees
    Altitude calculated: 7 + 3 degrees = 10 degrees

    Azimuth and altitude change between 01:43 and 02:01
    Elapsed time: 18 minutes
    Azimuth change: (230-225) degrees = +5 degrees
    Altitude change: (13-10) degrees = -3 degrees

    Object Measurements Summary:

    Date: 18 May 2014
    Times in CET, azimuths and altitudes in degrees:

    Time ____ Azimuth ____ Altitude
    01:43 ____ 225 ________ 13
    02:01 ____ 230 ________ 10

    Stellarium Data
    (the Stellarium screenshots can be viewed here)

    Stellarium date: 18 May 2014
    Stellarium times in CET (UTC+1:00)
    Azimuths and altitudes in degrees.

    Object: Mars
    Time ____ Azimuth ____ Altitude
    01:43 ____ 239 ________ 16
    02:01 ____ 243 ________ 13

    Object: Spica
    Time ____ Azimuth ____ Altitude
    01:43 ____ 223 ________ 14
    02:01 ____ 227 ________ 12

    Differences between my measurements and the Stellarium data
    (azimuths and altitudes in degrees)

    Object: Mars
    Time ____ Azimuth difference ____ Altitude difference
    01:43 ____ 239 - 225 = 14 ________ 16 - 13 = 3
    02:01 ____ 243 - 230 = 13 ________ 13 - 10 = 3

    Object: Spica
    Time ____ Azimuth difference ____ Altitude difference
    01:43 ____ 223 - 225 = -2 ________ 14 - 13 = 1
    02:01 ____ 227 - 230 = -3 ________ 12 - 10 = 2

    Considering this data, Spica is obviously the best fit. So if I trust my compass, my crappy sextant and my measurements, the object ought to be Spica, not Mars. Do you think this is correct?
     
    Last edited: May 20, 2014
  14. May 19, 2014 #13

    Chronos

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    The apparent airy ring around your highest res photo suggests it is a point source, like Spica. At 10x the rings of Saturn would be undetectable. It would, however, be noticeably larger than a star.
     
  15. May 20, 2014 #14

    russ_watters

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    Yes, chronos it did occur to me that this could be an out-of-focus point source - you may be right. 10x is so little magnification that it could be a planet and still basically be a point source.
    I don't understand the need for all of this data and effort: all of the objects we were discussing are visible to the naked-eye. If this is Spica, you should be able to look a little to your right and identify Mars. You should be able to figure all of this out in just a few seconds (Saturn is a little tougher since it is dimmer and pale).

    When I was in astronomy class, we had a mnemonic device:
    Follow the arc (of the Big Dipper) to Arcturus...
    Drive the spike (continue in the same direction) to Spica. Boom. 5 seconds to orient yourself and positively identify Spica. Then to the right is a brighter, red dot...

    [edit] I'm really not trying to be condescending here, but I just threw on some jeans (I was in bed), walked outside and recited the mnemonic and identified all three in just a few seconds. I'm really not seeing the problem. Mars in particular really can't be mistaken for anything else. It's too bright and too obviously red (and if it isn't attached to Orion, it isn't Betelgeuse).
     
    Last edited: May 20, 2014
  16. May 20, 2014 #15

    davenn

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    this is all what I suggested back in posts #8 and #11 :smile:

    Dave
     
  17. May 20, 2014 #16

    davenn

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    Dennis,

    your first pic in post #12 is still just showing an out of focus image of a star or something

    You need to experiment a bit and learn how to focus in a pinpoint star light source so that you produce pinpoint star images in the photo like this .....

    attachment.php?attachmentid=69916&stc=1&d=1400571972.jpg

    The stars in this image I did are just on the verge of having tails because of the 30 second exposure time here's the camera and its settings.....

    attachment.php?attachmentid=69917&stc=1&d=1400572326.jpg

    get a good star field pic where you can identify any planets and brighter stars and we can proceed from there :smile:

    cheers
    Dave
     

    Attached Files:

  18. May 20, 2014 #17

    davenn

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    OK

    had to scroll back to your first post to see what camera you were using
    Olympus VR-340 compact digital camera .... downloading and reading the manual for it
    explains a few things

    1) you are not going to be able to do star/planet photos as I suggested in my last post because
    the camera is pretty much totally auto.
    you will always get blobs for stars rather than pinpoints because the camera only has auto focus with no manual focus option.
    This means you cannot focus on stars or planets as there is nothing for the auto focus to lock onto.

    If you really want to do some star photos then you need to get a camera that you can have total manual control over so that you can set the aperture, focal length, focus, and exposure time

    2) I don't know your financial situation ... maybe you are young with little pocket money ... maybe a uni student with little spare funds ???
    when you have gathered some funds, pick up a second hand DSLR ( Digital SLR) camera ( one that lenses can be changed on) they are getting pretty cheap these days on the second hand market :smile:

    Then you can really start to get somewhere and produce useable images

    cheers
    Dave
     
  19. May 20, 2014 #18
    I did the measurements and calculations because I wanted to make the best of what I had. When I said I was terrible at identifying objects in the sky, I really meant terribly bad. I can identify the Sun, the Moon and the constellation Big Dipper (and Cassiopeia if I'm lucky), no more :biggrin:. It's sad, but true.

    Thanks! I will definitely try to learn more about the night sky and how to locate objects. I will start with playing around with Stellarium, I think.

    No problem at all! The problem was (and is) my almost complete lack of knowledge and experience in this field :smile:. My field is computer science & computer technology. I have never taken any astronomy class (regretfully), and I actually can't remember having been taught about locating objects in the sky at all. Maybe I have been taught, but I can't remember it. Never mind, I will have to learn it since I'm getting a scope later.

    I know. But I wanted to present my observations, even if they are sh*tty :biggrin:.

    Thanks! Wouldn't it be a good idea to start with playing around with Stellarium in order to learn the locations of the brightest objects, perhaps?

    Thanks for checking it up! No, I can't control the focus manually. I'm painfully aware of it :smile:.

    Thanks for the advice! I will keep a look out for second hand DSLR's. I also think I will buy a webcam after I have selected a telescope. I have also already got a Fujifilm FinePix 6900 Zoom, but I haven't (and can't) use it yet, since the battery and/or battery charger isn't working, and I also lack a memory card for it (it's an outdated card type, I will check around for second hand cards). But I will have a go at repairing/replacing the battery charger, haven't gotten around to it yet.

    My funds are fine. The main reason why I haven't got a telescope & other equipment yet, is that I want to wait until my other (hobby) projects are completed. I'm designing, experimenting with, and building audio equipment/electronics at the moment; a bunch of hifi loudspeakers, filters, microphones, preamplifiers, power amplifiers, guitar/bass amplifiers and cabinets. Lots of stuff, and it takes lots of time, but it's mighty fun :smile:. If I got a scope now, I would have a hard time keeping away from it. So I'll wait a while - I'll probably get a scope this autumn I think, when my audio projects have been completed.
     
    Last edited: May 20, 2014
  20. May 20, 2014 #19

    davenn

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    Hi ya Dennis

    Ohhh definitely get used to the location of the starts and planets .... if you have a laptop
    get Stellarium onto it and take it out under the nite sky ....Stellarium has a dark screen mode for that purpose so you don't destroy your night vision looking between the puter screen and the sky.

    Speaking of nite vision ... it takes a good 15-20 minutes for the avg person's eye to fully dark adapt.


    The cards and batteries are still readily available on eBay. But that said, altho the Fuji has manual mode for both focus and exposure settings. Its not going to be overly useful for astrophotography because the longest exposure setting is only 3 seconds.
    This is the same reason why I never used either my Fuji S7000 or S9500 for astrophoto's

    Pick up a second hand DSLR, Canon, Pentax, Nikon etc ... doesn't matter if it's a 5-10 year old model ... as long as it works well. It will have ( must have) a "B" position on the control wheel.
    B = Bulb setting its a manual mode where the shutter can be held open for as long as you want.
    and ALL DSLR's have manual focus capability

    We can go into this more at a later date and guide you through the use of :smile:


    a busy lad !! some good projects on the go there :smile:

    cheers
    Dave
     
  21. May 24, 2014 #20
    Hi again everybody!

    Thank you very much for the additional advice in post #19, davenn! I will save the info in this thread and go over it again when I get closer to my scope and camera purchases. Camera and scope advice is very good to have, particularly for novices like me :). I will definitely return to the forum for comments and advice regarding which equipment I plan to purchase. Thanks again!

    -------------------------------------------------------------------------------------------
    Well, my story just ain't over yet...:smile:

    Last night when I was walking home, I looked up at the sky and I saw my object of interest again. I can swear it was laughing at me, because I could hear the words "you think you know me, but you don't". No, seriously, I also saw some other objects too in the vicinity, and I thought about russ_watters' post #14...

    ...so I couldn't resist making another observation using this info. I fetched my compass and sextant, found a pretty good observation spot and took care looking at the sky (I did not take any photos). I made a sketch of what I saw, and made additional azimuth measurements, in order to compare with the Stellarium data. Here's my sketch (it's only basic and approximate, and I hope it's understandable) and another Stellarium screenshot to compare it with:

    My identifications:

    (1) - Arcturus (this object was very bright)
    (2) - Spica (visible, but definitely dimmer than the other objects
    (3) - My object of interest (very bright, my conclusion is that it is Mars, and it looked very much like Mars looks in Stellarium)
    (4) - Saturn? (it seems so, yet it was very much brighter than I thought)

    14071200910_9bf8269874_b.jpg
    14071200740_d17229eb26_b.jpg

    My conclusions so far:

    • The object of this thread (my object of interest) IS Mars, not Spica.
    • I need more stargazing and navigation experience.
    • I trust my compass (it's good enough).
    • My improvised sextant is too crappy to rely on.
    • Stellarium is a good program.
    • My camera is not appropriate at all for these kind of things (which I've already understood).
    • I've found a new, pretty good observation spot pretty close to my home.

    I will also take some photos of object 4 (Saturn?) when the weather here gets better, I simply have to see what the photos will look like...
     
    Last edited: May 24, 2014
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