On the 24th of October world-wide the
astronomers were confronted with a new phenomenon in the sky.
The inconspicuous
16.3mag*
bright comet P17/Holmes, discovered 1892 by
Edwin Holmes was by the time only photographically provable by
larger telescopes. On this day the comet increased in its
brightness within hours up to 2,5 mag. Suddenly in the
constellation Perseus a third bright "star" had emerged, which
can be discovered despite of the prevailing full moon situation
with the naked eyes easily. That means, the brightness increased
by a factor of nearly
500000, while
around the comet nucleus a circular expansion wave made itself
recognizable
Left map
for the 27th October 18:30 UTC/ 20:30 MESZ,
latitude 48.1°, longitude 11.4°, (South Germany). Right
map: Change of position till 18th November, 18:30 UTC / 19:30
MEZ
What had happened, that this cosmic ice
ball in a distance of 2,4 AU (approx. 360 millions km) to
the sun, suddenly begins itself to expand in a perfectly shaped
radius? Was it a cosmic collision, a chemical reaction, or the
wall "burst" around a large cavity within the comet body? May
after coming nearer to the planet Mars
(map)
the green manikin
did attack?
So far there is no clear explanation for it !
For more basic
info's
about the comet scroll down.
Update: 5th March and 6-9.
January 2008
1
mr
2
tb
3
tb
1) Comet 17P/
Holmes near the California Nebula,
5.3.08,
2) 17P/ Holmes
near the star Algol,
9.1.08, Nikon
300mm, f4, Exp 110 sec,
ASA 800 Canon 20D, Auerberg
3) 17P/ Holmes
near the star Algol,
6.01.08, Nikon
300mm, Exp. 120
sec, ASA 800 Canon 20D, Germerswang
Photo 1) Comet 17P/
Holmes near the California Nebula on the 3/5/2008. The very
difuse nebula measures now apprx. more than 4,5 times of the
moon diameter. This is equivalent to 2,25 degrees or 135arcmin.
Photo 2) and 3)
1/9/2008: Apprx. 84 arcmin lenght x 71 arcmin breadth is now the
expansion of 17P/ Holmes by a distance of 2,1 AU (315 Mio. Km)
from the earth. Despite the enormous widness of nearly 7,7 x 6,5
million kilometers the comet can be observed in dark areas
surprisingly effordless with the naked eye. But near big towns,
the object is really hard to observe.
(estimated brightness 4,2 mag*).
Update: 5th of December 2007
Left: Nikon
300mm, f4 ( 480 mm dig), Exp 90
sec, ASA 800 Canon 20D
With nearly 56
arcmin, 17P/ Holmes is nearly 2 times bigger as the moon
(may 3,7 mag*).
It can be still observed in dark areas with naked eye.
Update: 28th of November 2007
Nikon
300mm, f4 ( 480 mm dig), Exp 90
sec, ASA 800 Canon 20D
Canon
10 mm (16 mm dig), Exp 90
sec, ASA 800 Canon 20D, Auerberg, South Germany
Due to the comet
measures visual 45 arcmin, the diameter must reach up to 3,7
million kilometers. 17P/Holmes is fading surprising less
(may 3,5 mag*).
No problem to see the diffuse ball in dark areas with naked eye.
The comets surrounding material in comparision to the 1,5 x moon
diameter makes it easy to discover, although the momenty
brightness is declining. Watch vertical at midnight!
17th
of November 2007
Nikon
300mm x 2 times converted, f4 ( 960 mm dig), Exp.2x120
sec, ASA 800 Canon 20D
The expansion of
17P/ Holmes measures now 35 arcmin, and is visual archiving more
the the moon (30,5'). Since the 5th of November the comet is the
biggest object in our solar system. The diameter reaches up to
2,5 million kilometers. 17P/Holmes is dimming
(may 3,2 mag*),
but it is no problem to see the the expansiom wave with the
naked eye. By using normal binoculars it is together with the
"Perseus star" Mirfak a real magic view .
9th
of November 2007
Photo left, Nikon
300 mm, f4 ( 480 mm,1.6 x dig), Exp.. 3 x 120 sec, ASA 800.
Canon 20D.
Photo right;
Orion Optics
80/600 ED Exp.90 sec, ASA 800 Canon 20D
(9.Nov,0:10 UTC), Jaufenpass (1700 müNN), Sterzing. Thank's to
Martin for the borrowing of the 600ED!
Today the expansion
of 17P/ Holmes is around 21,5 arcmin, and visual archiving more
than 2/3rd of the moon (30,5'). It seems that the comet loose
it's tail. A may low solar wind isn't able to blow out the dust
from the center.
5th of November 2007
Today the expansion
of 17P/ Holmes is around 17 arcmin, and visual archiving the
wide as the half of the moon (30,5'). The real diameter of 1.2
mio km reaches now the size of our sun.*
1st-3rd of November 2007
1
2
Photo 1;
Meade SC 8"/ 2000
mm (3200 mm, 1.6 x dig); Exp. 84sec, ASA 800 Canon 20D
(1.Nov,0:15 UTC)
"It" is growing and
growing! The expansion wave of the now 1.63 AU (247 Mio km)
distanced comet from the earth is measuring in its diameter
around 13 arcmin! The green coma reaches with apprx. 32 arcmin
over a half degree and is a little bit bigger than the moon.
Advice*: The
size of the astronomy objects are in relation of the visual
figure seen from the earth. That means: 13 arcmin in a distance
of 247 million km are standing in proportion to 930.000 km!
(Moon diameter only 3400 km).
3 4
5
Photo 3,4; Nikon
300 mm, f4 ( 480 mm,1.6 x dig), Bel. 3 und 1 x 120 sec, ASA 800.
Canon 20D (3.Nov,0:15 UTC)
On the photos above
you can see a weak tail, but on the left photo you have to
amplifiy the contrast and graduation etc. of the image very
high.
31. October 2007
Strukturs inside the coma centre!
Team
Baader
;
Photos originated
at Baader Mammendorf. Overview with Canon 600/4, details
in the centre photographed through a TEK-APO with 140mm
opening and 1 m focal lenght. 8x 2min+4x1min+2x30s,
800-200 ASA. Camera 40D. Regards Martin!
29. October 2007
Meade SC 8"/ 2000
mm (3200 mm, 1.6 x dig); Exp. 22 sec, ASA 800 Canon 20D
Expansion wave since
the 27th of October apprx. 2,5 times more in its diameter. With
8 arcmin the comet reaches a quarter of the moon diameter. You
can see it with the unaided eye.
Team Baader
8x30s 1600ASA+4x30s 800ASA+2x30s 400ASA, MAK 10" f14, Canon 40D
ohne Brennweitenverl. Standort Mammendorf 29.10.22:00h
Nikon 300 mm, f4 ( 480
mm,1.6 x dig), exp. 4 and 11 sec, ASA 800. Canon 20D
The overlighting moon
moves away from the constellation Perseus, and the green coma
appears again.
26/27. October 2007, nearly full
moon!
1
2
3
1)Tamron 28 mm ( 35
mm,1.6 x digitally converted), f 5,6, exposure time 8 sec, ASA 400.
Canon 20D
2,3) Nikon 300 mm (
480 mm,1.6 x digitally converted), f4, exposure time 7 to 10 sec,
ASA 800. Canon 20D
The upper photos were taken in Moosburg Oberbayern
After in the entire Germany and half Europe
area a sturdy haze plate had situated itself for five days, not the
smallest cloud gap was even to be located in a radius of 300 km.
After the first attempt in Lenggries/Jachenau failed completely
because of a sudden high fog attack, the new hunt went into the
weather broadcast announced mini gap near the city of Regensburg. Of
corse it was also the purest haze battle and I had to change the
location almost for four times.
Meade SC 200/2000
mm (3200 mm, 1.6 x digitally converted); Exposure row 4sec,
10sec, 32 seconds, ASA 800. Canon 20D
Telescope
photos of 26th were taken near Landshut, South Germany
Diameter of expansion wave , about 3,5'
(arcmin); Green coma diameter about 6' (arcmin), Estmated brightness
of the coma, 2,2 mag*
It is remarkable that the pressure wave, I
suppose it was an explosion, spreads so fast that the size of the
sky object daily increases around 1,2 arcminutes. This
would comply an expansion speed around 40.000 km per day. If the
expansion wave stays constantly in its brightness, it will may be
possible to see a small ring (my own estimation!) with the unaided
eye in the night sky. Perhaps a brighter diffuse disk up to full
moon size could be observed. Let's wait what is happening the next
days /weeks.
But why
can we only see a comet without its well-known tail
(see comet
Swan M4)
This is well explained by the momentary
position sun-earth-comet
(map). From the
viewing point Earth, we can see directly on the nucleus. Behind the
nucleus the always sun turned away tail hides, and an asymmetrical
brightness inside the expansion wave is the reason.
*mag
= > light
magnitude:
Up to
mag +3-4 stars are visible nearby cities with
the naked eye, in very dark areas the seeing limit can reach up
to
mag +6-7.
The more higher numerical value is
given, the more weaker are the objects. E.g.
- 4,7 mag,
Venus glittering;
- 1,0
Sirius, brightest star;
+3,5
M31 Andromeda,
pale shiny oval)
All comet observations
from 2001 up to now ..
More about the comet 17P/ Holmes
astronomie.de
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