Search found 25 matches

by tnzkka
Wed Mar 01, 2017 1:29 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: A White Oval Cloud on Jupiter from Juno (2017 Feb 28)
Replies: 21
Views: 5222

Re: APOD: A White Oval Cloud on Jupiter from Juno (2017 Feb 28)

My thanks to Chris Peterson for his prompt answer dated Feb 28, 9.07pm. (My question was just above Chris' answer)
by tnzkka
Tue Feb 28, 2017 8:40 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: A White Oval Cloud on Jupiter from Juno (2017 Feb 28)
Replies: 21
Views: 5222

Re: APOD: A White Oval Cloud on Jupiter from Juno (2017 Feb 28)

Just a question: "Known as a white oval, the swirling cloud is a high pressure system equivalent to an Earthly anticyclone. " Does this statement include the assumption that the rotation of Jupiter 's axis and the rotation of Jupiter in its orbit round the sun are in the the same way as fo...
by tnzkka
Tue Jan 26, 2016 10:55 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Where Your Elements Came From (2016 Jan 25)
Replies: 36
Views: 13876

Re: APOD: Where Your Elements Came From (2016 Jan 25)

I wish to thank geckzilla and Cousin Ricky for their comments and link provided. They are a big help. And the promethium-fact mentioned by Cousin Ricky is new the me!
by tnzkka
Mon Jan 25, 2016 8:50 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Where Your Elements Came From (2016 Jan 25)
Replies: 36
Views: 13876

Re: APOD: Where Your Elements Came From (2016 Jan 25)

AFAIK element 43 Tc (Technetium) is also manmade, hence it's name.
At least the Dutch Wikipedia agrees with me.
Any comment or rectification on my knowledge or on Wikipedia(Dutch)?
by tnzkka
Tue Sep 20, 2011 1:43 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Kepler 16b: A Planet with Two Suns (2011 Sep 20)
Replies: 21
Views: 9879

Re: APOD: Kepler 16b: A Planet with Two Suns (2011 Sep 20)

rstevenson wrote: The video clearly shows the planet orbiting both stars, though there is an ambiguous moment as the point of view zooms away from the planet. Have another look. I beg to differ: From 0" until 23" (movie-time) observer and planet are clearly this ( = the same) side of the ...
by tnzkka
Tue Sep 20, 2011 8:25 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Kepler 16b: A Planet with Two Suns (2011 Sep 20)
Replies: 21
Views: 9879

Re: APOD: Kepler 16b: A Planet with Two Suns (2011 Sep 20)

Where is the centre of the orbit of this planet in the movie?
The planet seems to remain always at the viewers side of the yellow sun!
Yes, I think I know where it should be, (at the centre of gravity of the two suns) that is the inducement of my question.
by tnzkka
Mon Sep 05, 2011 2:28 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: HH 47: A Young Star Jet Expands (2011 Sep 05)
Replies: 23
Views: 4591

Re: APOD: HH 47: A Young Star Jet Expands (2011 Sep 05)

Thanks neufer Turbulent subsonic & supersonic gas jets are produced (or simulated) in laboratories all the time. Supersonic gas jets are unique in producing shock waves and those are precisely the features which are visible in today's APOD. & chris peterson Yes. It means that the material ma...
by tnzkka
Mon Sep 05, 2011 10:28 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: HH 47: A Young Star Jet Expands (2011 Sep 05)
Replies: 23
Views: 4591

Re: APOD: HH 47: A Young Star Jet Expands (2011 Sep 05)

@ Guest: as 500pesos states: there is no sound in vacuum. @ 500pesos: speed of sound depends on the kind of gas, its temperature and a few more variables; I'm fully aware of that. My thoughts are based on the fact that Mach(speed)numbers vary with all these. So what is the use and extra information ...
by tnzkka
Mon Sep 05, 2011 9:42 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: HH 47: A Young Star Jet Expands (2011 Sep 05)
Replies: 23
Views: 4591

Re: APOD: HH 47: A Young Star Jet Expands (2011 Sep 05)

Okay, there is a jet, so there is gas to propagate (even sound)waves, but is it meaningful to speak of:
is the supersonic jet
? Please, enlighten me.
by tnzkka
Mon Apr 04, 2011 7:31 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Verona Rupes: Tallest Known Cliff in... (2011 Apr 04)
Replies: 21
Views: 8529

Re: APOD: Verona Rupes: Tallest Known Cliff in... (2011 Apr

What struck me most is the fact that you land at the foot of the Miranda-cliff with about the same speed as a free-faller would have on Earth (the so called terminal velocity http://en.wikipedia.org/wiki/Terminal_velocity )
by tnzkka
Tue Sep 21, 2010 8:18 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Starry Night Over the Rhone (2010 Sep 21)
Replies: 41
Views: 5731

Re: APOD: Starry Night Over the Rhone (2010 Sep 21)

What should have been mentioned: (Stars/)constellations are painted as their mirror-image
by tnzkka
Wed Jun 16, 2010 10:00 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: APOD is 15 Years Old Today (2010 Jun 16)
Replies: 188
Views: 23026

Re: APOD: APOD is 15 Years Old Today (2010 Jun 16)

Congratulations on the third lustrum of a very well executed idea!
Many hapy returns.
by tnzkka
Mon Sep 15, 2008 7:09 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: The Heart and Soul Nebulas (APOD 14 Sep 2008)
Replies: 3
Views: 1993

To get a better overview of this region, see APOD 31-dec-2007, Hearth and Soul and Holmes.
by tnzkka
Wed Feb 27, 2008 7:09 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Properties of sulfuric acid (APOD 26 Feb 2008)
Replies: 23
Views: 6058

I know...at last!!

Thank you, bystander,

I should not only have looked up the properties of sulfuric acid, but of Venus' surface too.

Taught me a good lesson for next time! :oops:

Bye.
by tnzkka
Wed Feb 27, 2008 12:00 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Properties of sulfuric acid (APOD 26 Feb 2008)
Replies: 23
Views: 6058

Wandering away from the initial question

Please, ladies and gentlemen, Will you please realise how few of the "answers/replies" above relate to my initial question and how many "answers/replies" are just wandering away? To quote myself:"How comes sulfuric acid is called volatile in this text?" (Unquote myself)...
by tnzkka
Tue Feb 26, 2008 12:57 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Properties of sulfuric acid (APOD 26 Feb 2008)
Replies: 23
Views: 6058

I guess it's taking account of the temperatures & pressions in Venus's atmosphere...
Volatylity is a relative notion, I'm aware of that; so OK for ocurring temperature, but nót for occuring pressure (on ground level of course) therefore I'm asking here.
by tnzkka
Tue Feb 26, 2008 10:08 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Properties of sulfuric acid (APOD 26 Feb 2008)
Replies: 23
Views: 6058

Properties of sulfuric acid (APOD 26 Feb 2008)

The text going with today's APOD states: "...recombined into the volatile sulfuric acid." Wikipedia states about sulfuric acid: Melting point 283 K (10 degrees C); Boiling point 610 K (337 degrees C) Substances with boiling- and meltingproperties like these do not seem to be volatile to me...
by tnzkka
Thu Mar 22, 2007 3:35 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Partial eclipse over Goa (APOD 22 Mar 2007)
Replies: 3
Views: 1990

Orin, the picture is great! I fully agree to that.
It is the caption that I am referring to.
by tnzkka
Thu Mar 22, 2007 8:19 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Partial eclipse over Goa (APOD 22 Mar 2007)
Replies: 3
Views: 1990

Partial eclipse over Goa (APOD 22 Mar 2007)

Please, a solar eclipse is not due to the "New Moon's shadow" but to the moon's silhouette. And of course, when the moon's silhouette covers the Sun it is New Moon.
by tnzkka
Sun Feb 04, 2007 8:23 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Shadow of a martian robot (APOD 4 Feb 2007)
Replies: 18
Views: 7282

Shadow of a martian robot; APOD 4 feb 2007

I wonder if round the "head"of the shadow a Heiligenschein is visible.
See: http://www.weather-photography.com/albu ... igenschein and if so, if it is another proof of a martian atmosphere.

THX for any comments
by tnzkka
Thu Dec 28, 2006 8:13 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: What is wrong? If anything is. (APOD 27 Dec 2006)
Replies: 6
Views: 3576

Thanks!!
Happy New Year
by tnzkka
Wed Dec 27, 2006 10:06 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: What is wrong? If anything is. (APOD 27 Dec 2006)
Replies: 6
Views: 3576

What is wrong? If anything is. (APOD 27 Dec 2006)

From today's APOD comment:
1. Its title: NGC 5067;
2. Its comment: IC 5067, also known as The Pelican Nebula;
And 3. From the link to November 30th: Also known as IC 5070.

My question is: What is the exact name of the nebulae of today and of Nov. 30th?
by tnzkka
Thu Apr 13, 2006 2:18 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: No, the Antarctice ice sheet is NOT shrinking.
Replies: 30
Views: 14247

@ starnut: try this one: http://www.msss.com/mars_images/moc/CO2_Science_rel/

I'm sure however that we all would be better off with a more sober lifestyle.
by tnzkka
Wed Feb 22, 2006 8:42 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD picture 22-feb-2006
Replies: 2
Views: 2173

APOD picture 22-feb-2006

Newbee here, but...with a question: Telesto orbits Saturn always just ahead of the much larger moon Tethys This is an ordinary troyan-system: Saturn-Thetys-Telesto, I assume. What is the role of te Sun in view of the stability of this system? See: http://map.gsfc.nasa.gov/ContentMedia/lagrange.pdf T...