General Astronomy, Cosmology and Space Exploration Discussion

Discussion in 'Science' started by BlueRaven, Jul 23, 2013.

  1. Thudd

    Thudd Member

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  2. Renegade40D

    Renegade40D Member

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    Any suggestion on a starter telescope to be used for both star gazing and on earth items such as whales etc. Something decent around without a huge price tag, hoping for something around the 500 mark
     
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    BlueRaven

    BlueRaven Member

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    Mate, I have got a Celestron Firstscope 60 (similar to this but earlier model with wood/metal tripod) with all accessories that I bought from a stall at a school fete in great condition but have barely used.
    Looking to get rid of it as it's really just a cool-looking thing that takes up space in our tiny flat at the moment. Too much light pollution on the north shore to make full use of it anyway.

    Cover postage and maybe 5-10 bucks for packaging materials/time to get to the P.O. and it's yours. Happy to do pickup for free if you're in Sydney or know someone who is.

    It's very much a "starter" scope and probably lower quality than what you were willing to spend, but hey... free. :)
    Specs follow:

    60.0mm / 2.4" Aperture Refracting Telescope
    All glass optics
    Aluminium tube
    5x24 Finderscope
    Star diagonal
    20mm (35 Power) Eyepiece
    6mm (117 Power) Eyepiece
    Adjustable-height Wood/Metal Tripod
    Altazimuth Mount with fine/coarse azimuth adjustment

    Will snap some pics for you tonight and edit the post.
     
    Last edited: Oct 18, 2013
  4. broox

    broox Member

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    I'm sure this was linked somewhere here, but I can't recall exactly where... :lol:

    The Most Important Image Captured By Hubble

    http://all-that-is-interesting.com/important-image-captured-by-hubble

    I always wondered how they could tell the distance of a galaxy/etc.
    I'm sure its a lot more complicated than their quick explanation, but yeah, red shift. cool stuff. :thumbup:
     
  5. Renegade40D

    Renegade40D Member

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    Thanks for the offer, this is actually a birthday present for a family member so looking for something new.

    Where do you live though as might be worth while for the niece and nephew.
     
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    BlueRaven

    BlueRaven Member

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    North Shore of Sydney, near Chatswood.

    I've been away all weekend but I'll give the thing a dust and take some photos for you tonight. It's in excellent condition but probably not worth it unless you can pick it up or have someone else do so, as it would be quite a bulky (ie. expensive) package to post - Box dimensions are 750x270x170 and weight would be ~5kg as the wood tripod is quite sturdy and heavy.
     
  7. de_overfiend

    de_overfiend Member

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    more info about the comet ISON... should be clearly seen around dawn throughout November from the east coast of australia

    http://www.sydneyobservatory.com.au/2013/comet-ison-from-the-southern-hemisphere/

    Quote from above link:

    Currently, skilful amateur astronomers, who are willing to lose their early morning sleep, are able to image the comet and websites such as Spaceweather.com are building up large collections of their spectacular images. Next month the comet’s increased brightness should make it easier to observe, but, as can be seen from the chart above, it is also rapidly appearing progressively lower in the dawn sky.

    One of the many reasons this is an interesting comet is that it is making its first approach to the inner solar system. That means that scientists can only guess at how bright it will become at the time it is closest to the Sun. Professional and amateur astronomers will be eagerly observing the comet from the ground, while a whole fleet of spacecraft have turned their cameras in its direction.

    Another major unknown is whether the comet will survive its passage through the Sun’s atmosphere, the corona. There its central core or nucleus will be subject to both strong heating and bombardment by radiation, while the Sun’s strong gravitational pull will be trying to tear it apart through tidal forces. Still the best guess from scientists is that the nucleus or at least a large chunk of it will manage to sweep around the Sun and start making its way out of the solar system.


    from another site ISON's location as of 16/10/13:

    http://1.bp.blogspot.com/-KUaHlyhIv...J3c/2g6NMFALamE/s1600/ISON_16Oct_labelled.jpg

    And seen from adelaide at 5:30am on 18/10/13

    http://2.bp.blogspot.com/-QkBMBJ2Ri...AJ3k/9F67XggF_5s/s1600/Mars_18-10-13_0530.png

    Anyone got any amateur shots the want to share?


    Edit: nov 3 is a new moon so should be good for viewing before dawn
     
    Last edited: Oct 24, 2013
  8. de_overfiend

    de_overfiend Member

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    BlueRaven

    BlueRaven Member

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    http://io9.com/the-birth-and-death-of-stars-in-one-spectacular-photo-1472524200

    Posted yesterday on io9, images from the ESO's Very Large Telescope.

    What a fantastic name. :)

    Here's a couple of really cool interactive simulation models that people might enjoy playing with... they are pretty good timesinks!

    http://www.solarsystemscope.com
    http://www.solarsystemscope.com/ison

    Also be sure to check out the "more models" link at the top right for more cool stuff.
     
    Last edited: Nov 29, 2013
  10. avandonk

    avandonk Member

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    Last edited: Nov 30, 2013
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    BlueRaven

    BlueRaven Member

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    Great photo Bert, thank you for posting it. :thumbup:

    As best I can tell, the high-density cluster at the top-left is the same supernova/nebula system shown in the ESO image...?
    There's several other areas which look similar, but the density of young stars and the orientation of a few bright older ones in that cluster seems to mark it as the one.

    EDIT: Actually no, i see it now... it's out on the left-hand edge of your photo, just above the horizontal centreline of the image and rotated 90 degrees from the ESO picture.
    That was a fun "Where's Wally?" exercise... like finding a needle in a needle-stack. :)

    Really beautiful and awe-inspiring stuff. I could look at images like these all day.
    From the sheer number of gas clouds and the huge amount of new stars within them, it seems the LMC really is a major star factory.
     
    Last edited: Dec 5, 2013
  12. Akh-Horus

    Akh-Horus Member

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    Need members to advise who has astronomy equipment and location for those of us who want to learn but cant justify the good gear at this point.

    Up my way is exceptional for astronomy btw.
     
  13. .Radiant

    .Radiant Member

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    nvm.... still early...
     
    Last edited: Dec 6, 2013
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    BlueRaven

    BlueRaven Member

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    "The Sagan Series"

    Just found this excellent short video series using narration by Carl Sagan.

    http://www.youtube.com/playlist?list=PLF17F07CFC3208E29

    From the creator Reid Gower's youtube channel:

    Really well done for an independent project. The editing and stock footage used has some powerful imagery that pairs wonderfully with Sagan's mesmerising voice-over.

    Well worth a watch. There's also the "Feynman Series" as companion pieces on his channel.
     
  15. shOOter---

    shOOter--- Member

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    I was taking some shots of Orion Neb the other night & I got a visit from a satellite! It is a bit shaky as it was windy but it was the last chance I was going to get before the moon & I had to get my fix! you know how it is :p


    Click to view full size!
     
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    BlueRaven

    BlueRaven Member

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    Someone needs to inform that satellite that it is illegal to streak on the field...
    .
    .
    .
    *tumbleweed*
    .
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    .
    *cricket chirping*
    .
    .
    .
    Sorry, couldn't help myself. :Paranoid:

    Really nice photo mate, thanks! :thumbup:
     
  17. [PnP]dredd

    [PnP]dredd Member

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  18. Danske

    Danske Member

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    In the earlier episodes of Cosmos they talk about the spectral lines that are seen in light rays, which can show the composition of a star depending on what spectral lines are shown, I get this, but my question is:

    If the light from a star passes through a gas cloud (or something that will change it's spectral lines), doesn't that mean we could be inaccurately recording what the star is made from?

    What do we do about this?

    p.s. I'm a total newb, so go easy :cool:.
     
  19. Foliage

    Foliage Member

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    The gas cloud itself will absorb some of the stars, however you can differentiate the two as the stars spectrum will be continuous, the gas cloud will absorb certain parts based on its composition.

    The way around it is you would be able to focus on certain parts of the gas cloud (zoom in) and then other parts of the planet to subtract one signature from the other, if you were at the absolute limit of resolution of your device where you could not differentiate the cloud from the planet/star, then you would also almost certainly not even be able to tell it was a star either.

    If you wanted to know what a planets composition is, then you essentialyl observe a stars reflection off it, and it will absorb certain frequencies based on its composition. If you observed this light through a gas cloud, you would also need to observe the original star through the gas cloud, then add back in the star + cloud absorption spectrum to the planets absorption spectrum to get it's true spectrum.

    example here
    http://astronomy.nmsu.edu/geas/lectures/lecture19/slide02.html

    One thing that definitely does affect the spectral lines though is the doppler effect, also known as red shift. The same as how a car moving away from you sounds different to one that is stationary, light from objects moving away from you also looks different.

    http://en.wikipedia.org/wiki/Redshift
     
    Last edited: Jun 23, 2014
  20. Foliage

    Foliage Member

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    [​IMG]

    add the inverse of one to the other
     

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