Has Comet ISON fragmented? Is this
really even Comet ISON?
Why are there three nuclei and why are they elongated?
Good questions - and we have answers!
The NASA partyline ...
Thus saith the Lord, thy Redeemer,
the Holy One of Israel; I am the Lord thy God
which teacheth thee to profit, which leadeth thee by
the way that thou shouldest go.
Isaiah 48:17 KJV
SYRIAN UPDATE ...
9-02-13 Hummingbird027's Updates on
End-Time and Prophetic News (41:32)
http://www.youtube.com/watch?v=MRxpDzLNjb8 (Preview)
ISON Comet
Spacecraft
- NASA explains !!!
Comet ISON Controversy! (Sep
02, 2013)
A recent image of Comet ISON, recorded by the Hubble
telescope, has surfaced online and caused quite a stir. Far
from looking like a comet, we see an almost geometric pattern
of streaks of light that look far, far different to the image released by the Hubble team.
Understandably, this raises more than a few eyebrows, and in
the absence of qualified explanation, lends itself to all
manner of interpretation - some quite elaborate!
So this week we are going to take a look at the somewhat
controversial image you see opposite, and explain exactly
what's happening.
It is on a routine basis that we see beautiful astronomical pictures
appear online, whether they be from Hubble telescope, Cassini,
SDO, or any number of other space-based missions. Often times
these images are jaw-droppingly beautiful and colorful, and
understandably embraced by the internet community. Many people
are happy to enjoy these processed images as they are
presented, but others prefer to dig a little deeper and find
the original data files from which they were derived. This is
fabulous, and to be encouraged and applauded as it certainly
educates the public about astronomy and science! But those
that choose to dig around like this need to understand exactly
what they are seeing when they view "raw" data files, and why
they often look so different to the pretty ones that we put
online.
The following explanation applies to nearly all
astronomical imaging satellites, but here we are just going to
use the example of Hubble, since it's the focus of this
particular Comet ISON controversy.
When satellites take astronomical images of galaxies,
planets, comets, etc, the images they record are very rarely
inherently pretty. There is no color,
typically no artistic lens flares, the images can be dominated
by stray light, noise, cosmic rays, and all manner of other
features depending on where in space they are looking. Indeed,
many "raw" spacecraft images are just downright ugly! In order
to make pretty pictures, scientists often have to take several processing steps to
remove instrumental effects, noise, zodiacal light, etc, and
then apply appropriate scaling, contrasting and color to the
images to return the wonderful pictures we all love to see.
The end result is sometimes barely recognizable from the
original data.
In the image above (which we recommend you click on to
see a comparison with its "pretty" counterpart image), we see
something that doesn't look a lot like a comet, and very much
not like the beautiful Hubble Heritage image
of ISON. We see three distinct nuclei that appear as short
streaks oriented in different directions. Why is this?
The Hubble image of Comet ISON is not a single exposure
but instead a series exposures taken at different times.
Hubble is in orbit around the Earth, so is actually moving
through space at a very high velocity. When
compiling this image, the Hubble team aligned all of the
exposures such that the stars remained fixed in space. This
greatly enhances the detail of the stars and galaxies in the
field of view and makes the image far prettier to look at.
Unfortunately this also means that the comet (which is very
much closer to Hubble than it is to the stars) appears in a
slightly different location in each of the exposures that are
taken, because the Space Telescope never sits still!
Furthermore, the images taken were long exposures -- up
to 490-seconds. Any photographer will tell you that a long
exposure of a moving bright light will lead to a streak in the
image, and that is exactly what we see with the comet.
Finally, the streaks are oriented in different directions due
to Hubble's elliptical orbit around Earth. Depending on where
the telescope is at a given time on this ellipse, it leads to
a "streak" that trails in a different direction.
There's a bit more to it than this, but that's the basic
overview. This information is not the kind of thing we
scientists expect most people to know, so it does not surprise
us when there is confusion about images like this. However,
wild speculation about UFOs and conspiracies doesn't really
help anyone! Instead we urge people to contact us
and ask us directly. We are always happy and more than willing
to talk about our work.
(The trick is getting us to shut up once we've
started!)
http://www.isoncampaign.org/potw-sep02
http://www.isoncampaign.org/
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