Search found 17686 matches
- Mon Jul 15, 2024 2:06 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Tadpole Galaxy from Hubble (2024 Jul 15)
- Replies: 25
- Views: 9998
Re: APOD: The Tadpole Galaxy from Hubble (2024 Jul 15)
Astronomical images, by convention, should be presented with east counterclockwise from north. (And ideally with north up, but this convention is often ignored in order to match the geometry of the object to that of the camera, or sometimes for purely aesthetic ends.) This is what we see when we lo...
- Mon Jul 15, 2024 1:16 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Tadpole Galaxy from Hubble (2024 Jul 15)
- Replies: 25
- Views: 9998
Re: APOD: The Tadpole Galaxy from Hubble (2024 Jul 15)
p.s. great close-up image AVAO! (but do you mean by "mirrored" that this is not the actual state of the galaxy but an optical effect? I'm not sure I understand) Astronomical images, by convention, should be presented with east counterclockwise from north. (And ideally with north up, but t...
- Mon Jul 15, 2024 12:24 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Meteor Misses Galaxy (2024 Jul 14)
- Replies: 19
- Views: 8302
Re: APOD: Meteor Misses Galaxy (2024 Jul 14)
Take the comparison of 3 million light years to 3 ten-thousandths of a light second - what is that for? (The latter number works out to 5.6 miles and so is probably wrong, too many decImal places, as that meteor track is most likely starting at least 50 miles up) By my calculations 0.0003 light sec...
- Mon Jul 15, 2024 12:17 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Solar System Family Portrait (2024 Jul 13)
- Replies: 18
- Views: 5928
Re: APOD: Solar System Family Portrait (2024 Jul 13)
The Earth appears to have photographic diffraction spikes in this image. But the diffraction spike on the right appears to be a tiny bit "fatter" and a tiny bit brighter and differently colored than the diffraction spike on the left. Voyager I has two cameras, a narrow-field one and a wid...
- Mon Jul 15, 2024 12:09 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Meteor Misses Galaxy (2024 Jul 14)
- Replies: 19
- Views: 8302
Re: APOD: Meteor Misses Galaxy (2024 Jul 14)
Indeed, the color is due to the composition of the meteor (and of the atmosphere). And if we had a spectroscopic data, we could say a lot about what the meteoroid was made of. But with only three broadband channels (red, green, and blue) we really don't have much information. The colors of the trai...
- Mon Jul 15, 2024 12:04 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Meteor Misses Galaxy (2024 Jul 14)
- Replies: 19
- Views: 8302
Re: APOD: Meteor Misses Galaxy (2024 Jul 14)
I am more amazed by everything else other than the galaxy and the colored lighted meteorite streak. Look at the number of objects in visible light. I'm not seeing any refraction spikes etc, so assuming every single light blob is some galaxy. Yes ? How many ? 1000s.. Seems denser than deep/ultra dee...
- Sun Jul 14, 2024 1:39 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Solar System Family Portrait (2024 Jul 13)
- Replies: 18
- Views: 5928
Re: APOD: Solar System Family Portrait (2024 Jul 13)
The Earth appears to have photographic diffraction spikes in this image. But the diffraction spike on the right appears to be a tiny bit "fatter" and a tiny bit brighter and differently colored than the diffraction spike on the left. Voyager I has two cameras, a narrow-field one and a wid...
- Sun Jul 14, 2024 1:24 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Meteor Misses Galaxy (2024 Jul 14)
- Replies: 19
- Views: 8302
Re: APOD: Meteor Misses Galaxy (2024 Jul 14)
I am of course wondering about the very red-colored dust coming off the meteor. I'd like to ask Chris why this dust is so red, but I know that he would only say that the color is due to the composition of the meteor, and since he himself knows nothing about the composition of this meteor, he can't ...
- Sat Jul 13, 2024 9:19 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Solar System Family Portrait (2024 Jul 13)
- Replies: 18
- Views: 5928
- Sat Jul 13, 2024 8:40 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Solar System Family Portrait (2024 Jul 13)
- Replies: 18
- Views: 5928
Re: APOD: Solar System Family Portrait (2024 Jul 13)
Uh, a "60 frame mosaic"? I count only 38. Also, just to be clear, the only object actually visible in any of these frames (other than the insets) is the Sun, which is the large bright spot near the center of the arc of frames, and whose bright rays appear in other nearby frames. Correct? ...
- Fri Jul 12, 2024 2:17 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Jones-Emberson 1 (2024 Jul 12)
- Replies: 4
- Views: 3887
Re: APOD: Jones-Emberson 1 (2024 Jul 12)
The logo of the imagers?hankbernath@msn.com wrote: ↑Fri Jul 12, 2024 2:12 pm what is the ringed object in the lower right of the image displayed?
- Fri Jul 12, 2024 1:36 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Globular Cluster Omega Centauri (2024 Jul 11)
- Replies: 15
- Views: 5281
Re: APOD: Globular Cluster Omega Centauri (2024 Jul 11)
Except it's not likely that many stars in a globular cluster have planets. The view from inside a rich globular cluster might be something like this: Inside 47 Tucanae William Harris and Jeremy Webb.png Inside globular cluster 47 Tucanae. Illustration: William Harris and Jeremy Webb But Chris is ri...
- Thu Jul 11, 2024 9:13 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Globular Cluster Omega Centauri (2024 Jul 11)
- Replies: 15
- Views: 5281
Re: APOD: Globular Cluster Omega Centauri (2024 Jul 11)
The distance to the center of the cluster is known with very high accuracy (5.24±0.11 kpc based on Gaia parallax) so the positional shifts of seven stars close to the center yield accurate radial velocity values, which define minimum 3D velocities. As those velocities are greater than the cluster e...
- Thu Jul 11, 2024 8:27 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Globular Cluster Omega Centauri (2024 Jul 11)
- Replies: 15
- Views: 5281
Re: APOD: Globular Cluster Omega Centauri (2024 Jul 11)
Fast-moving stars around an intermediate-mass black hole in ω Centauri The fastest and the centremost star (Fig. 1, star A) has a 2D proper motion of 4.41 ± 0.08 mas/yr (113.0 ± 1.1 km/s). This is higher than the escape velocity of the cluster if no IMBH is present, v_esc = 62 km/s. The combined co...
- Thu Jul 11, 2024 4:31 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Globular Cluster Omega Centauri (2024 Jul 11)
- Replies: 15
- Views: 5281
Re: APOD: Globular Cluster Omega Centauri (2024 Jul 11)
Except it's not likely that many stars in a globular cluster have planets.Ham Todd wrote: ↑Thu Jul 11, 2024 4:00 pm I often wonder what the sky would look like for a person living on a planet that orbited around a star in this cluster! I'm pretty sure the view would be awesome!
- Tue Jul 09, 2024 6:36 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Exoplanet Zoo: Other Stars (2024 Jul 08)
- Replies: 22
- Views: 6459
Re: APOD: Exoplanet Zoo: Other Stars (2024 Jul 08)
This article says that "super Earths" might actually be better at fostering life than our puny little Earth, due to more plate tectonic activity and the greater ability to hold on to an atmosphere, both due to the higher gravity and internal heat. (But I'm not quite convinced: a thicker a...
- Tue Jul 09, 2024 6:23 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Exoplanet Zoo: Other Stars (2024 Jul 08)
- Replies: 22
- Views: 6459
Re: APOD: Exoplanet Zoo: Other Stars (2024 Jul 08)
This article says that "super Earths" might actually be better at fostering life than our puny little Earth, due to more plate tectonic activity and the greater ability to hold on to an atmosphere, both due to the higher gravity and internal heat. (But I'm not quite convinced: a thicker a...
- Tue Jul 09, 2024 5:04 pm
- Forum: The Observation Deck: Latest Sky Photography
- Topic: Submissions: 2024 July
- Replies: 180
- Views: 72172
Re: Submissions: 2024 July
Comet 13P/Olbers This Halley-type comet with a period of 69 years just passed perihelion a couple of weeks ago. Captured here is the typical green glow of the coma (from CN and C 2 emissions) and reflected sunlight from a diffuse trailing dust cloud. Very prominent is the blue ion tail which shows ...
- Tue Jul 09, 2024 1:27 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Exoplanet Zoo: Other Stars (2024 Jul 08)
- Replies: 22
- Views: 6459
Re: APOD: Exoplanet Zoo: Other Stars (2024 Jul 08)
I was so crushed yesterday after I lost a long post that I had spent hours composing, so that after I had mostly restored that post, I couldn't bring myself to make another. But I really wanted say that the most common type of exoplanets (of those that we have so far detected) are neither "Jup...
- Mon Jul 08, 2024 1:21 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Exoplanet Zoo: Other Stars (2024 Jul 08)
- Replies: 22
- Views: 6459
Re: APOD: Exoplanet Zoo: Other Stars (2024 Jul 08)
As you can see, WASP-12b is egg-shaped due to its proximity to its parent star. Yes, but both the APOD and illustrator Robert Lea (who illustrated the SPACE article about WASP-12b) got the planet's color wrong! https://upload.wikimedia.org/wikipedia/commons/thumb/8/80/The_Pitch-Black_Exoplanet_WASP...
- Mon Jul 08, 2024 1:27 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Iridescent Clouds over Sweden (2024 Jul 07)
- Replies: 8
- Views: 3369
Re: APOD: Iridescent Clouds over Sweden (2024 Jul 07)
If you love clouds and you love astronomy then no matter what condition the sky, you'll enjoy a look up after sunset! But I also love nitpicking... today's APOD says that iridescent clouds are "relatively rare" but they are actually very common. If there are no clouds, you can't see iride...
- Sat Jul 06, 2024 11:58 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: NGC 7789: Caroline's Rose (2024 Jul 06)
- Replies: 10
- Views: 3742
Re: APOD: NGC 7789: Caroline's Rose (2024 Jul 06)
https://knuklhdsobsrv.wordpress.com/wp- ... etch-1.jpgjohnnydeep wrote: ↑Sat Jul 06, 2024 11:41 pm Ok, where are the "small telescope views" that show "nested rose petals"?
- Sat Jul 06, 2024 4:41 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: NGC 7789: Caroline's Rose (2024 Jul 06)
- Replies: 10
- Views: 3742
Re: APOD: NGC 7789: Caroline's Rose (2024 Jul 06)
EDIT: Okay! I couldn't help myself. I googled "Trumpler 5 age" and got a few different answers, among them Log Age, 9.61. (What does that mean, Chris? I have an idea, but I think that would perhaps make the cluster too old.) It means log(age in years). So 9.61 means 4.07 billion years, si...
- Fri Jul 05, 2024 2:55 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Time Spiral (2024 Jul 01)
- Replies: 37
- Views: 9891
Re: APOD: Time Spiral (2024 Jul 01)
What kind of explanation is "before" not having any meaning in the context of the universe? The entire illustration is a timeline of the universe. That doesn't mean there's a "before". That word is pretty hard to define when time doesn't exist. I'm reminded of the "What did...
- Wed Jul 03, 2024 3:55 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Time Spiral (2024 Jul 01)
- Replies: 37
- Views: 9891
Re: APOD: Time Spiral (2024 Jul 01)
That doesn't mean there's a "before". That word is pretty hard to define when time doesn't exist.Avalon wrote: ↑Wed Jul 03, 2024 2:40 am What kind of explanation is "before" not having any meaning in the context of the universe? The entire illustration is a timeline of the universe.