On the 8th
of February, I woke up with the firm intention of getting some telescope
observation time and bring home one or two sketches. At about 5:40, my first
sketch was done and as always I took some time to contemplate the sky with just
my eyes.
The circle shows the FOV |
Scorpius
was showing off its long and curvish figure while Virgo was reaching its zenith
with Jupiter on board. I knew Libra should be in middle of those, but I could
not trace well its shape. Then, I realized I had forgotten Libra and never had
aimed my telescope at it. I guessed that after all the galactic and nebular show
in Virgo and Scorpius, there was nothing left in Libra.
I grabbed
my phone, opened the Stellarium app and looked for Libra. My mobile version showed
a shape that definitely did not look like a scale but more like a kite made
with the stars Zubeneschamali, Zubenelgenubi, Brachium and Zuben Elakrab (all
arabic names) and with some sort of tail from this last one star to 46 Lib. I
personally like more the H.A. Rey´s version of Libra’s shape because it looks like
a scale. To make the shape, he made use of two more stars (39 and 40Lib) instead of 46 Lib. A curious fact about Libra is that once it
was considered part of the scorpion and in fact today, 3 of the names of its
brightest stars refer to the claws of the scorpion.
While I
was comparing the visual information from my phone with the sky, I saw that
there was a globular cluster of 8.52 magnitud in Libra called NGC 5897. I
thought, “I haven’t heard of it, but I am going to give it a try.” I aimed my findercope to the star Brachium and
from there I star hopped a couple of grades to the east until I found 3 stars
of 8th magnitude placed in a slightly curved row. In the view with the 40mm
eyepiece the whole scenario looked like a number 7 (due to the horizontally
flipped view). Right to the upper part of that particular asterism there was a
ghosty circular patch of light at its left side. It was easy to see with low
magnification even with direct vision, but it had nothing else to offer than
the mere appearance of its existence among the background.
I was
searching for this globular cluster and it seems to be the solitary globular
cluster in Libra. Classified as class XI
(being I the most concentrated and XII the least concentrated) is in fact
a loose globular cluster and probably that is why it looked so dim and ghosty
in the eyepiece.
There is
also more to see in Libra of course. Some double stars and the star Gliese 581
or HIP 74995 in Stellarium. This 10th magnitude star is the “sun” of a planetary
system that contains Gliese 581g, a planet similar in size to the Earth,
situated in the habitable zone of its star and that therefore could sustain
life.
Happy
stargazing,
LG
Edited
by: Jennifer Steinberg (editor in chief)
SOURCES
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