Search found 144 matches

by rigelan
Mon Jun 25, 2012 12:04 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Apollo 17 at Shorty Crater (2012 Jun 24)
Replies: 38
Views: 7432

Re: APOD: Apollo 17 at Shorty Crater (2012 Jun 24)

Man, what an experience to actually walk the edge of the crater on the moon!
by rigelan
Fri May 11, 2012 6:45 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Sun vs Super Moon (2012 May 11)
Replies: 11
Views: 3136

Re: APOD: Sun vs Super Moon (2012 May 11)

Ann. Your story is prose, and yet the way it is written, it feels poetic.
by rigelan
Fri Apr 13, 2012 4:29 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: A Dust Devil of Mars (2012 Apr 13)
Replies: 27
Views: 3929

Re: APOD: A Dust Devil of Mars (2012 Apr 13)

Water is a very dense fluid - and even at slow speeds can cause a lot of damage. Air on Earth is less dense than water - it takes quite a bit of speed, upwards of 100mph to create significant damage. I wonder how fast the wind speeds would have to be on Mars to create anything significant enough to ...
by rigelan
Wed Mar 28, 2012 12:15 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Earthshine and Venus Over Sierra de... (2012 Mar 28)
Replies: 16
Views: 4329

Re: APOD: Earthshine and Venus Over Sierra de... (2012 Mar 2

At what point will we actually see the crescent of Venus? I have never seen it with my binoculars. I thought with a zoomed in image like this one - I might see it. I think right now, its not a crescent anyway - its a 3rd quarter phase. Does it need a specific zoom to see, does the brightness need to...
by rigelan
Thu Jan 07, 2010 3:41 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Spotty Surface of Betelgeuse (2010 Jan 06)
Replies: 42
Views: 15702

Re: The Spotty Surface of Betelgeuse (2010 Jan 06)

My other question now is: Doesn't betelgeuse spin? I wonder how they made sure that spinning didn't affect the image.
by rigelan
Thu Jan 07, 2010 3:34 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Spotty Surface of Betelgeuse (2010 Jan 06)
Replies: 42
Views: 15702

Re: The Spotty Surface of Betelgeuse (2010 Jan 06)

In section 5.3 of their document http://arxiv.org/pdf/0910.4167v2 they state that the limiting resolution they achieved is around 11 mas. T1, the northwestern of the two spots is around 11 mas wide. They state that they trust the size of this object. T2 on the other hand, the southeastern one, has a...
by rigelan
Thu Jan 07, 2010 3:17 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Spotty Surface of Betelgeuse (2010 Jan 06)
Replies: 42
Views: 15702

Re: The Spotty Surface of Betelgeuse (2010 Jan 06)

To me it still seems like a grid of around 3X7 pixels from the interferometry. Then it looks like it was digitally smoothed. So my question is this: How high do you think our resolution of the data in this image is? Reminds me of these images of Pluto. Not directly taken, but calculated. The brightn...
by rigelan
Thu Jan 07, 2010 2:01 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Spotty Surface of Betelgeuse (2010 Jan 06)
Replies: 42
Views: 15702

Re: The Spotty Surface of Betelgeuse (2010 Jan 06)

I'm willing to bet the visual patterns look like that just because that's how big the pixels are in our interferometry calculation. It looks to be 3 pixels wide and 7 pixels tall. The pixel grid is angled about 15 degrees from vertical. Probably because that's the direction the telescopes were tipped.
by rigelan
Tue Dec 29, 2009 5:10 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Rigel and the Witch Head Nebula (2009 Dec 29)
Replies: 9
Views: 3252

Re: Rigel and the Witch Head Nebula (2009 Dec 29)

Looks like its my turn to say, "Hey star, nice name!"
by rigelan
Thu Nov 26, 2009 4:46 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: All sky milky way panorama (2009 November 25)
Replies: 7
Views: 1625

Re: All sky milky way panorama (2009 November 25)

It is a terrific image and must have taken a lot of patience by Dr Mellinger to stitch the over 3000 individual images together to produce the panorama. It therefore seems churlish of me to say that I prefer the image in the APOD of 2001 February 2 that was brought up through the "here" a...
by rigelan
Thu Nov 19, 2009 10:49 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: 2009 Leonids (APOD 2009 November 19)
Replies: 5
Views: 1400

Re: 2009 Leonids (APOD 2009 November 19)

I'm no fan of the cloudy nights we had here.
by rigelan
Sun Sep 13, 2009 11:53 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Summer Night in Astronomy Town (2009 Sept 12)
Replies: 15
Views: 2498

Re: Summer Night in Astronomy Town (2009 Sept 12)

Thanks Chris, much appreciated.

Not being an astro photographer myself, it is difficult for me to have a point of reference.
by rigelan
Sat Sep 12, 2009 3:37 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Summer Night in Astronomy Town (2009 Sept 12)
Replies: 15
Views: 2498

Re: Summer Night in Astronomy Town (2009 Sept 12)

After perusing our milky way images, it seems most are taken out in the middle of nowhere. Sahara Badlands Mauna Kea Devils Tower Sequoia National Park Well I suppose here's one with a foreground shot that's near a town http://antwrp.gsfc.nasa.gov/apod/ap080905.html This APOD is a lovely image, but ...
by rigelan
Sat Sep 12, 2009 3:23 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Summer Night in Astronomy Town (2009 Sept 12)
Replies: 15
Views: 2498

Re: Summer Night in Astronomy Town (2009 Sept 12)

Chris Peterson wrote:Nevertheless, if you're in a dark location, an exposure long enough to bring out this type of sky leaves the foreground completely dark.
Got an example picture? I mean if the foreground for milky way pictures is not typically this bright, what is a typical brightness for a nearby foreground?
by rigelan
Sat Sep 12, 2009 3:13 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Summer Night in Astronomy Town (2009 Sept 12)
Replies: 15
Views: 2498

Re: Summer Night in Astronomy Town (2009 Sept 12)

Yeah, I figured all the regulars around here DID know that. But no one had actually mentioned it in this thread, so I thought I'd mention it for the casual reader.
by rigelan
Sat Sep 12, 2009 2:55 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Summer Night in Astronomy Town (2009 Sept 12)
Replies: 15
Views: 2498

Re: Summer Night in Astronomy Town (2009 Sept 12)

Of course the city is not actually putting out as much light as appears in the picture. The camera shutter is open for many seconds. The sky shows the Milky Way during those many seconds of exposure, and the ground shows the shadows of the nearby town after many seconds of exposure. The picture appe...
by rigelan
Sat Sep 05, 2009 12:08 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: 6 Years of Saturn (2009 September 4)
Replies: 36
Views: 4761

Re: 6 Years of Saturn (2009 September 4)

This summer I saw so many things with my binoculars, Neptune, Uranus, Jupiter's Moons, Andromeda Galaxy, that I looked at Saturn for its rings. I had tried and tried and failed, No wonder they weren't visible to my binoculars. Head on! Looks like i'll have to wait a year or so for better images of t...
by rigelan
Mon Aug 24, 2009 10:52 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Morning Glory Clouds Over Australia (2009 Aug 24)
Replies: 27
Views: 3802

Re: Morning Glory Clouds Over Australia (2009 Aug 24)

http://antwrp.gsfc.nasa.gov/apod/ap090824.html Nice picture, but ... where's the astronomy? I've defended the choice of weather and atmospheric pictures before, even on flimsy grounds like "the air is what we look through to see the stars." But in this picture we're not even looking up to...
by rigelan
Sun Aug 09, 2009 7:33 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Saturn's Iapetus: Painted Moon (APOD 2009 August 9)
Replies: 15
Views: 2172

Re: Saturn's Iapetus: Painted Moon (APOD 2009 August 9)

One way to tell a solid/liquid core would be to see how it 'wiggles' in its orbit. If the core is molten, then it is able to move around somewhat, affecting the mass distribution of the entire moon, which would create a wobble in its orbit. Another way might be to see the surface temperature of the ...
by rigelan
Mon Aug 03, 2009 1:18 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: T 4 2 Tauri al (APOD 2009 August 3)
Replies: 2
Views: 1302

Re: T 4 2 Tauri al (APOD 2009 August 3)

I usually get the impression that the skies are unchanging. Except for the planets, nothing seems to ever be different. But on the time-scale of astronomy these stars ARE mere young children. And these things do change. T Tauri stars are now generally recognized as young -- less than a few million y...
by rigelan
Mon Aug 03, 2009 3:05 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Jupiter's New Impact Scar (2009 July 23)
Replies: 57
Views: 7955

Re: Jupiter's New Impact Scar APOD20070723

I ride my bike with sunglasses at all times for the same reason. When I rode I wore an open face helmet - hitting a (big) fly at 60mph stung a bit, and was fatal for the fly. What was really interesting was riding through a swarm of bees at that speed. Like Ralph Nader's Corvair, bees can be unsafe ...
by rigelan
Tue Jul 14, 2009 3:57 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Moons and Jupiter (2009 Jul 14)
Replies: 55
Views: 7430

Re: Moons of Jupiter (7/14/09)

I opened up Kstars for that night, July 11th (Actually July 12th) at around 2 AM local time. Copied a picture here. u Capricorn magnitude = 5.1 Neptune magnitude = 7.8 Jupiter magnitude = -2.6 Callisto magnitude = 5.7 The little blue dot below Neptune is NC 1408, a galaxy of some sort, I don't think...
by rigelan
Tue Jul 14, 2009 3:01 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Moons and Jupiter (2009 Jul 14)
Replies: 55
Views: 7430

Re: Moons of Jupiter (7/14/09)

Yeah, these definitely are the right distances to be Jupiter's moons. The four largest (Galilean) ones anyway. They are a significant angle away from Jupiter, and are quite a sight to see through binoculars. Night after night you can see their apparent positions change. If you don't have equipment t...
by rigelan
Thu May 21, 2009 9:33 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: IC 4592: A Blue Horsehead (2009 May 21)
Replies: 22
Views: 3390

Re: And I looked, and behold a pale horse (APOD 2009 May 21)

orin stepanek wrote:http://apod.nasa.gov/apod/ap090521.html

Actually; this APOD looks more like a horses head than does the Horsehead Nebula! 8)

Orin
The horsehead nebula looks more like a chess piece than a horse.
by rigelan
Tue May 05, 2009 11:06 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: Titan Beyond the Rings (APOD 2009 May 5)
Replies: 17
Views: 2275

Re: Titan Beyond the Rings (APOD 2009 May 5)

The picture is very surreal with Epimethius being crystal clear in focus and Titan in the back (seemingly out of focus) Though, I suspect this IS how titan looks when in focus - The image lengths are both pretty much the same at this point, infinity compared to the curvature of the camera. They shou...