The Image Index is a system based on likes received on images, that incentivizes the most active and liked members of the community. Learn more.
The Contribution Index (beta) is system to reward informative, constructive, and valuable commentary on AstroBin. Learn more.
Imaging telescopes or lenses: William Optics Megrez 80 FD
Imaging cameras: QHYCCD QHY 22
Guiding telescopes or lenses: ZWO 60/280 GuideScope
Guiding cameras: QHY5L-II Mono
Focal reducers: William Optics FF/FR 0.8x II
Software: PixInsight PixInsinght 1.8 RC7 · PHD guiding · photoshop · APT - Astro Photography Tool
Dates:March 17, 2019 , March 31, 2019
Frames:
Astrodon B Gen II: 12x300" bin 2x2
Astrodon G Gen II: 12x300" bin 2x2
Astrodon HII-3nm: 13x900" -40C bin 1x1
Astrodon L Gen II: 16x600" -40C bin 1x1
Astrodon R Gen II: 12x300" -40C bin 2x2
Integration: 8.9 hours
Avg. Moon age: 17.90 days
Avg. Moon phase: 51.37%
Astrometry.net job: 2787867
RA center: 14h 3' 23"
DEC center: +54° 21' 46"
Pixel scale: 2.035 arcsec/pixel
Orientation: 232.738 degrees
Field radius: 0.918 degrees
Resolution: 2559x2000
Locations: Nedelkovo, near Sofia, Bulgaria
Data source: Backyard
Usually a set of various numbers is what we find first when we search for an object, however sometimes they could be quite inquiring… M101 is relatively close spiral galaxy around 21 million ly away from Erath. Its diameter is estimated to ~170 000ly and many sources state that it is much bigger than Milky Way. This is curious because our galaxy is estimated to 150-200 000ly? M101 is considered to contain ~1 trillion stars compared to 100-400 billions in our galaxy. Comparing the estimated masses there is great difference - 100 billion solar masses for M101 against 800-1 500 billion in Milky Way!? How such difference can be explained? Reading further to see that M101 has no central back hole. How big is our supermassive black hole – “just” ~4.1 million solar masses, not enough to close the numbers… Maybe we have more dwarfs, neutron stars and small black holes? M101 has shown many x-ray sources explained as stellar-mass black holes and exploded stars (i.e. there are dwarfs and neutron stars)… Very curious! Peculiar is also the mass distribution – the central bulge takes only ~3% giving most of the calculated mass to the periphery and satellite dwarf galaxies. Having a “grand spiral design” nearby gives good opportunities to take a look which we can’t have on our galaxy. After all it could be that we just don’t know enough for Milky Way yet :) And how we could know enough when we speak about galaxies! They are universes in the Universe…
Other interesting fact about M101 is that its spiral arms host more than 3 000 active large star formation, which is in the very high range compared to similar galaxies. The Ha regions were the initial idea of this project - to take a bit unusual point of view on “regular” target (see the first image – 3h 15min in Ha). It is quite interesting and the next time will try with bigger scope. After that decided to make a full course – to gather some LRGB and see what will come out. Combining 5 channels in an image was first time job for me, but am pleased with the results especially taking into account that it is just 80mm scope :) Hope that you will like it too!
You have no new notifications. |
This page or operation is not available at the moment, because AstroBin is in READ ONLY mode. For more information, please check out our Twitter feed: https://twitter.com/AstroBin_com
This feature is only offered at higher membership levels.
Would you be interested in upgrading? AstroBin is a very small business and your support would mean a lot!
If this user has been harassing you, and you shadow-ban them, all their activities on your content will be invisible to everyone except themselves.
They will not know that they have been shadow-banned, and the goal is that eventually they will get bored while having caused no harm, since nobody saw what they posted.
You will remove your shadow-ban on this user, and their comments, messages, etc, will appear again on your content.
Such limitation improves the website as a whole by discouraging people from creating fake accounts to like their own content. Thank you for understanding!
Currently, your Image Index is .
To learn more about the Image Index, please visit the FAQ page. Thanks!
Comments