2020-06-02

CN论坛的挖掘

Picot 1 / Napoleon’s Hat

https://www.cloudynights.com/topic/708575-picot-1-napoleons-hat/

Bootes Void

是无法看不见的，但是用夜视仪能不能就不知道了

船状星云中的色彩幻觉

好吧，我是在最明亮的星云中看到微弱颜色的人之一。在黑暗的天空中，尤其是Carina星云在12英寸的天空中看起来呈淡橙色，这不仅对我来说，而且对与我一起看到它的每个人来说都是如此。与M42的红色和蓝绿色完全不同。

在澳大利亚，18’’Dob里面Eta Carina看上去有点粉红色，但真正使我无法抵挡的部分是中央的Homunculus星云：它是明亮的金色！

简直叹为观止。这里有很多细节。

而LMC的捕鸟蛛星云（Doradus 30）十分壮观。我认为它比ε Carinae更好。

如何寻找M87喷流

https://www.cloudynights.com/topic/703935-tracking-down-m87s-jet-a-success/

在定位时首先排除UGC星系的误判。然后C组恒星最容易，之后可以按照方向寻找喷流。

http://www.deepskyforum.com/forumdisplay.php?8-Object-of-the-Week-2020-(OOTW)

业余天体之最追寻

Abell 2151, the Hercules cluster - most distant galaxy I saw was ~500-600 million light-years away
NGC 3179 - 400 million light-years away, most distant galaxy I’ve seen that isn’t part of a cluster
Stephan’s Quintet - Furthest galaxy is 350 million light-years away
Abell 779, cluster in Lynx - most distant galaxy I saw was ~350 million light-years away
Abell 426, Perseus Cluster - most distant galaxy I saw was ~300 million light-years away

CTA102, quasar - 8 Bn LY

Q0957+561 Twin Lensed Quasar - 8.7 Bn LY

Mrk 421, BL Lacerta Object - @ 400 Mn LY

3C 371, BL Lacerta Object - @ 730 Mn LY

3C 273, quasar - @ 2.4 Bn LY

Andromeda’s parachute with Z= 2.377. 11 billion light years.

Coma GC

IC1101 Gigantic elliptcal at a billion ly - Largest known galaxy

Hercules GC

QSO PG1634+706

Andromeda’s Parachute - Newest, bestest Lensed QSO ever.

Corona GC

QSO LB19

Abell 838 in Hydra (~1 BLy} has so far been my most distant galaxy cluster observed.

Serveral cluster galaxies appeared as almost stellar dots at 343x, under perfect seeing and dark skies.

Those dots popped in only when using averted vision.

Brightest members at ~15 magv

15” f4,5 Obsession.

Observed on Doi Inthanon, northern Thailand, 8000 ft high location with no light pollution.

在完美的视线和黑暗的天空下，星系团在343x处几乎呈恒星状。

I’ve been looking for targets among BCGs in a number of catalogs in VizieR and HEASARC, mainly compiled from SDSS data. I started to realize that neither the extent nor the total luminosity can be a best indicator of visibility at >1 billion ly: In a word; extent negates brightness. So I am focusing on those with the densest central concentration - their cores- as defined by their peak spectroscopic flux - at 5000 angtroms, -i.e I’m looking for the brightest BCG cores. For these giant elliptical galaxies, the peak flux shifts increasingly red-ward of our maximum visual sensitivity - lt’s like a curtain closing off our view - as the redshift increases. The emitted flux falls off rapidly blue-wards of the thermal emission peak so this is a very serious impediment going beyond 1 billion ly.

The brightest cores will remain detectable at somewhat greater distances (though appearing more like very,VERY, VERY faint stars), and when found in tight groups, of which a “stellar” example would be Abell 1689 (13h 11m 30s +1d 20m 22s) z~.171 (…further than 3c273…!) maybe 15 mag in R, combined- so, anyone with a really big (under 48”) dob, consider this an extreme distant galaxy cluster challenge for Spring… (Actual human night vision required, averted or not.)

疏散星团形状

韦伯星团

http://cdsarc.u-strasbg.fr/ftp/J/A+A/558/A53/atlas/

超紧凑矮星系=UCD

科迪列夫斯基的尘云

Kordylewski Cloud

早在1961年,科迪勒夫斯基就在L5位置观察到了两个模糊的类似星团的物体,但从那以后就再也没有观察到它们。

IFN（星际通量星云）较亮的部分也很可能会干扰Kordylewski云的观测。

海丁格的刷子

Haidinger’s brush

光的偏振

广角星云调查

https://www.cloudynights.com/topic/687682-new-hii-regions-sky-map-at-x1/

https://www.mdwskysurvey.org/recent-highlights

http://www.reinervogel.net/index_e.html?/Sharpless/Sharpless_summer_e.html

自定义星图

https://www.cloudynights.com/topic/685236-is-there-a-way-to-make-my-own-custom-star-charts/

Sky Map Pro 10

PP3 celestial charting program

https://www.cloudynights.com/articles/cat/articles/observing-skills/free-mag-7-star-charts-r1021

麦哲伦之谜终于解决了

Over the years since 2005 a handful of amateur astronomers have reported a wide, elongated swath of vanishingly faint emission in the deep Southern skies. It begins near the SW corner of the LMC, brightens as it passes through Mensa, parallels the long axis of Chameleon 4° to 5° S of the chameleon’s body, touches Octans near the S celestial pole, brightens somewhat as it transects the body of Apus, and fades imperceptibly into Triangulum Australe. It is variously described as a “broad, even band of emission” “A cometary tail streaming from the LMC,” “About as bright as the the Zodiacal light as it nears the gegenschein,” and “Resembles an elongated form of the gegenschein.”

即使在相当大的范围内，您也只能在最明亮的星系中看到旋臂(M33，M51，M101和M81等等)

球状星团里面的恒星：红色的是红巨星，蓝色的是蓝离散星，最小的光点是红矮星和白矮星

NGC104 由于大量的红巨星而看上去呈现淡黄色。

爱因斯坦十字架–可见的最小孔径？

A Cen 尘埃带

灰区据说7x50可见尘埃带。

https://www.cloudynights.com/topic/636881-dust-lane-in-centaurus-a-with-binoculars/

分解球状星团的最小孔径

10x50可以分解omega Cen

63mm用侧视法据说可以分解M13

4寸APO可以分解M4

巴纳德E

据说是很容易的目标，曾被8x42所观测到

对于任何暗星云，黑暗的天空和良好的透明度至关重要。