Search found 11 matches

by BillLee
Thu Jan 23, 2020 3:36 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Globular Star Cluster NGC 6752 (2020 Jan 23)
Replies: 17
Views: 4129

Re: APOD: Globular Star Cluster NGC 6752 (2020 Jan 23)

I wonder what the night (?) sky would look like to an imaginary resident of a planet circling one of those stars in that cluster.

Regards,

Bill Lee
by BillLee
Wed Nov 27, 2019 9:55 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Mercury and the Quiet Sun (2019 Nov 14)
Replies: 27
Views: 7808

Re: APOD: Mercury and the Quiet Sun (2019 Nov 14)

Can somebody explain why there will only be 14 transits in the 21st century. Seems to me that every time Mercury goes around the sun that it would be visible against the sun as a backdrop. I cannot envision the geometry that would limit that to only 14 in 100 years. Mercury's orbit doesn't lie on t...
by BillLee
Thu Nov 14, 2019 3:23 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Mercury and the Quiet Sun (2019 Nov 14)
Replies: 27
Views: 7808

Re: APOD: Mercury and the Quiet Sun (2019 Nov 14)

Can somebody explain why there will only be 14 transits in the 21st century. Seems to me that every time Mercury goes around the sun that it would be visible against the sun as a backdrop. I cannot envision the geometry that would limit that to only 14 in 100 years.
by BillLee
Mon Sep 16, 2019 1:55 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: A Harvest Moon (2019 Sep 13)
Replies: 22
Views: 5390

Re: APOD: A Harvest Moon (2019 Sep 13)

Something strange with this picture. Somebody please explain. The picture looks like, and the caption says "...the full moon shining on with beautiful iridescent clouds at sunset." but the full moon can NOT be in a picture of a "sunset"! The moon is full when it is opposite the ...
by BillLee
Sat Sep 14, 2019 9:42 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: A Harvest Moon (2019 Sep 13)
Replies: 22
Views: 5390

Re: APOD: A Harvest Moon (2019 Sep 13)

Something strange with this picture. Somebody please explain. The picture looks like, and the caption says "...the full moon shining on with beautiful iridescent clouds at sunset." but the full moon can NOT be in a picture of a "sunset"! The moon is full when it is opposite the s...
by BillLee
Thu Dec 22, 2016 12:32 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: An Airplane Glory (2016 Dec 22)
Replies: 21
Views: 2340

Re: APOD: An Airplane Glory (2016 Dec 22)

The cause of the glory is still being researched and is reflect, refract, and diffract sunlight backwards towards the Sun.
Isn't this the same physics/geometry as a rainbow?

R/

Bill Lee
by BillLee
Sun May 22, 2016 9:57 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: LL Orionis: When Cosmic Winds Collide (2016 May 22)
Replies: 14
Views: 3819

Re: APOD: LL Orionis: When Cosmic Winds Collide (2016 May 22)

The description says "analogous to the bow wave of a boat moving through water or a plane traveling at supersonic speed."

A plane need not be traveling at "supersonic speed" to create a bow wave.
by BillLee
Sun Sep 27, 2015 12:11 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Tonight: A Supermoon Lunar Eclipse (2015 Sep 27)
Replies: 13
Views: 4944

Re: APOD: Tonight: A Supermoon Lunar Eclipse (2015 Sep 27)

Somebody needs to tell the NASA illustrator who produced the neat little video that the moon doesn't move south to north. Check out the video at about the 29-30 second mark.
by BillLee
Thu Jun 14, 2012 1:43 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: M13: The Great Globular Cluster in... (2012 Jun 14)
Replies: 27
Views: 4730

Re: APOD: M13: The Great Globular Cluster in... (2012 Jun 14

What would the night sky look like on a planet around a sun within a cluster like that? Would there even BE a "night sky"?
by BillLee
Wed Feb 15, 2012 12:04 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Rosette Nebula (2012 Feb 14)
Replies: 29
Views: 7042

Re: Thank you Ann, re: parallax and proper motion Re: Rosett

Thank you Ann for the enlightening explanation of parallax and proper motion, as well as spectra and brightnesses. I sorta knew this stuff, but to have it presented in relation to a beautiful image of the nebula surrounding a cluster I've seen through my little telescope in the backyard really brin...
by BillLee
Tue Feb 14, 2012 12:49 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Rosette Nebula (2012 Feb 14)
Replies: 29
Views: 7042

Re: APOD: The Rosette Nebula (2012 Feb 14)

Warning : Newbie alert! I am NOT an astonomer or anything! But I enjoy the fantastic images in the APOD. I have gathered a large number of them and use them for my screen background. Question: How do you distinguish stars referenced in an image like the one today (Rosette Nebula) from foreground st...