Search found 1114 matches

by VictorBorun
Wed May 05, 2021 9:02 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: STEVE over Copper Harbor (2021 May 05)
Replies: 14
Views: 5832

Re: APOD: STEVE over Copper Harbor (2021 May 05)

Ann wrote: Wed May 05, 2021 6:18 am
STEVE and starry background MaryBeth Kiczenski.png
4) Pollux
5) Castor
Ann
Any chance that the North pole or a magnetic pole is the center of this STEVE arc?
by VictorBorun
Wed May 05, 2021 8:57 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: STEVE over Copper Harbor (2021 May 05)
Replies: 14
Views: 5832

Re: APOD: STEVE over Copper Harbor (2021 May 05)

Here's another interesting article on STEVEs research: http://www.sci-news.com/othersciences/geophysics/steve-mechanisms-07137.html This pic is rather confusing. http://cdn.sci-news.com/images/enlarge6/image_7137_2e-STEVE.jpg The SAID ring (with a STEVE segment) around the polar magnetic field is s...
by VictorBorun
Sun May 02, 2021 9:41 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Clouds of the Carina Nebula (2021 May 02)
Replies: 8
Views: 6333

Re: APOD: Clouds of the Carina Nebula (2021 May 02)

orin stepanek wrote: Sun May 02, 2021 12:06 pm 280px-Eta_Carinae.jpg
Is Eta Carinae a double star?
Will some one please help me see this Eta Carinae butterfly thing in the posted pic?
by VictorBorun
Fri Apr 30, 2021 12:23 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: North Star: Polaris and Surrounding Dust (2021 Apr 28)
Replies: 21
Views: 15012

Re: APOD: North Star: Polaris and Surrounding Dust (2021 Apr 28)

I feel I miss something.
The background nebula behind Polaris is Integrated Flux Nebula, but may lie within the thick Milky Way disk and have plenty of stars to frontlight parts of it locally.
OK.
But why label such nebula an Integrated Flux at all?
by VictorBorun
Thu Apr 29, 2021 1:03 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: North Star: Polaris and Surrounding Dust (2021 Apr 28)
Replies: 21
Views: 15012

Re: APOD: North Star: Polaris and Surrounding Dust (2021 Apr 28)

I can't resist showing you one of the pictures where Polaris, or at least its halo, looks blue. It is an image by Rogelio Bernal Andreo, and in this picture, Polaris was visited by Comet C/2014 Q2 Lovejoy with its green coma, blue tail and short rather green-looking antitail. Nice!! :D Ann https://...
by VictorBorun
Tue Apr 27, 2021 4:54 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: A Sagittarius Triplet (2021 Apr 26)
Replies: 10
Views: 5090

Re: APOD: A Sagittarius Triplet (2021 Apr 26)

Ann wrote: Mon Apr 26, 2021 10:16 am So, you math people out there, I challenge you! Will you figure out the distances to these stars for me?
I applied the figures for facebook 3d AI, but it turned out no good :(
https://www.facebook.com/victor.borun/p ... 8519499897
by VictorBorun
Mon Apr 19, 2021 6:02 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Rainbow Airglow over the Azores (2021 Apr 18)
Replies: 6
Views: 3127

Re: APOD: Rainbow Airglow over the Azores (2021 Apr 18)

what my eyes see in the pic: cyan (only in some places, must be an accessory bottom or belly part of an ionosphere wave) to green to yellow to orange to red to magenta what I read: 95 km high, faint blue range glow emitted by O₂ molecules; 90 to 100 km high, 558 nm, green emitted by neutral O atoms....
by VictorBorun
Thu Apr 15, 2021 11:13 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Pencil Nebula Supernova Shock Wave (2021 Apr 14)
Replies: 6
Views: 2963

Re: APOD: The Pencil Nebula Supernova Shock Wave (2021 Apr 14)

Guest wrote: Wed Apr 14, 2021 5:57 pm If this is a side-on view, does that mean all these other supernova remnants we see as circular aren’t actually spheres but more flattened circles?
a thin ghostly-transparent sphere shell is mostly visible edge-on where it's thicker
by VictorBorun
Thu Apr 15, 2021 8:08 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Galaxy, the Jet, and a Famous... (2021 Apr 15)
Replies: 21
Views: 6999

Re: APOD: The Galaxy, the Jet, and a Famous... (2021 Apr 15)

We appear to be looking down on the accretion disk and yet the jets seem to be heading in the wrong direction for that to be true. Here's my attempt to 3d-convert the radiowave pic of the clouds at the M87 jet-ends Here's my attempt to 3d-convert the IR pic of the clouds at the M87 jet-ends I used ...
by VictorBorun
Mon Apr 12, 2021 7:11 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Alnitak and the Flame Nebula (2021 Apr 12)
Replies: 43
Views: 13797

Re: APOD: Alnitak and the Flame Nebula (2021 Apr 12)

so Alnitak has a large parallax and therefore is close to us and the Flame Nebula has a zero or small parallax and can never be backlighted from Alnitak. Now the Flame Nebula can not be backlighted from the stars within at a small angle; we get to see all angles from 0 to 90°. And how can it be yell...
by VictorBorun
Mon Apr 12, 2021 2:02 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Alnitak and the Flame Nebula (2021 Apr 12)
Replies: 43
Views: 13797

Re: APOD: Alnitak and the Flame Nebula (2021 Apr 12)

So I don't think that dust can make an intrinsically red (or pink, or magenta) emission nebula yellow. However, an embedded region of star formation may well produce quite a lot of blue light, which may then be reddened to a fairly deep yellow hue because of lots of intervening dust. I guess Alnita...
by VictorBorun
Mon Apr 12, 2021 8:35 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Alnitak and the Flame Nebula (2021 Apr 12)
Replies: 43
Views: 13797

Re: APOD: Alnitak and the Flame Nebula (2021 Apr 12)

That's a striking rendition of the Flame Nebula, looks more like a painting. Unfortunately it's been flipped left-right. I had to rotate by 174,5°after the flip: https://scontent.fhel4-1.fna.fbcdn.net/v/t1.6435-9/172216489_3829845087136574_4155472068737884903_n.jpg?_nc_cat=100&ccb=1-3&_nc_s...
by VictorBorun
Mon Apr 12, 2021 8:07 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Alnitak and the Flame Nebula (2021 Apr 12)
Replies: 43
Views: 13797

Re: APOD: Alnitak and the Flame Nebula (2021 Apr 12)

That's a striking rendition of the Flame Nebula, looks more like a painting. Unfortunately it's been flipped left-right. Yes Ann, I've often wondered about the yellow colour of the Flame Nebula. I'm guessing dust has something to do with it? Can the Flame Nebula reside in front of Alnitak? Backligh...
by VictorBorun
Mon Apr 05, 2021 8:33 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Veil Nebula: Wisps of an Exploded Star (2021 Apr 05)
Replies: 21
Views: 7712

Re: APOD: Veil Nebula: Wisps of an Exploded Star (2021 Apr 05)

In images of the complete Veil Nebula, even studious readers might not be able to identify the featured filaments. Okay, that sounds like a veiled challenge to locate today's APOD in the APOD from 2019-10-31 (https://apod.nasa.gov/apod/ap191031.html). Capture.png And it does seem rather challenging...
by VictorBorun
Mon Apr 05, 2021 10:08 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Ingenuity on Sol 39 (2021 Apr 03)
Replies: 16
Views: 5285

Re: APOD: Ingenuity on Sol 39 (2021 Apr 03)

APOD Robot wrote: Sat Apr 03, 2021 4:06 am The Mars Ingenuity Helicopter, all four landing legs down.
At the first look it seems scary, the way the car is sitting down so the copter's legs almost scratch the ground.
At the second look you notice the shadow cast by the right background leg and know that there is in fact a gap.
by VictorBorun
Sun Apr 04, 2021 6:05 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Ingenuity on Sol 39 (2021 Apr 03)
Replies: 16
Views: 5285

Re: APOD: Ingenuity on Sol 39 (2021 Apr 03)

Our geocentric units long since got insufficiently precise. So what? We never abandon them, just re-define in a more precise way. Meter used to be 1 / 40 million of the Parisian meridian. Gram used to be the mass of 1 cubic centermeter of water at the temperature near 0°C where the density peaks. Se...
by VictorBorun
Sun Apr 04, 2021 1:48 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Aurorae and Lightning on Jupiter (2021 Mar 24)
Replies: 19
Views: 7685

Re: APOD: Aurorae and Lightning on Jupiter (2021 Mar 24)

In a dense atmosphere like Jupiter's the mean free path is not going to be much more than one or two molecules and so the electric field needed to instigate lightning is just absolutely massive which is why there is little lightning elsewhere on Jupiter - the charges are dissipated by the general a...
by VictorBorun
Thu Apr 01, 2021 11:06 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Exploring the Antennae (2021 Mar 27)
Replies: 13
Views: 6474

Re: APOD: Exploring the Antennae (2021 Mar 27)

JohnD wrote: Sun Mar 28, 2021 7:53 pm
VictorBorun wrote: Sun Mar 28, 2021 11:47 am What do they call a dwarf of known origin? Something ibn NGC 4038 ?
A gnome?
gnome can't be used in a phrase like a gnome of X

I think "A gnome of a galaxy" would mean something other than a seperated patch of a galaxy
by VictorBorun
Thu Apr 01, 2021 11:03 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Exploring the Antennae (2021 Mar 27)
Replies: 13
Views: 6474

Re: APOD: Exploring the Antennae (2021 Mar 27)

giant elliptical galaxy M60 has a tiny compact companion galaxy that is called M60-UCD1. UCD1 means Ultra Compact Dwarf 1, and M60 means that this dwarf is a satellite of M60. So I guess it would be possible for a dwarf of NGC 4038 to be named after NGC 4038, but I'm not aware of any dwarf galaxies...
by VictorBorun
Sun Mar 28, 2021 11:47 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Exploring the Antennae (2021 Mar 27)
Replies: 13
Views: 6474

Re: APOD: Exploring the Antennae (2021 Mar 27)

In the image at left, note the tail emanating from NGC 4038. The tail extends to the left and down. Note that at the end of it, star clusters have formed, which may later turn into dwarf galaxies. In the image at right, I would guess that the dark blue stuff seen in the tail is (neutral) hydrogen g...
by VictorBorun
Fri Mar 26, 2021 2:50 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Medusa Nebula (2021 Mar 26)
Replies: 35
Views: 11563

Re: APOD: The Medusa Nebula (2021 Mar 26)

Are there 2 standard rulers to gauge the distance: 1) Doppler velocity to multiply by the time since the explosion and divide by angular size 2) light echoes from the central dwarf flashes to compare the lag between the pale far edge (north east at the pic) and the near edge (south east at rhe pic),...
by VictorBorun
Thu Mar 25, 2021 1:24 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Leo Trio (2021 Mar 20)
Replies: 19
Views: 6680

Re: APOD: The Leo Trio (2021 Mar 20)

Suppose for a moment, that a cosmologic string (comphessed between 3 voids) is likely to form galaxy clusters with rotation axis along that string, and that main galaxies that sink down to the center of a cluster tend to rotate along the same direction. Than the gas disks should have parallel or al...
by VictorBorun
Wed Mar 24, 2021 11:42 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Aurorae and Lightning on Jupiter (2021 Mar 24)
Replies: 19
Views: 7685

Re: APOD: Aurorae and Lightning on Jupiter (2021 Mar 24)

The magnetic field concentrates the solar winds ions into the upper atmosphere forming the aurora. I wonder if Jupiter'.s magnetic field is large and powerful enough to focus cosmic rays at the poles too and these act as triggers for the lightning I thought a magnificent lightning needs a good insu...