Starship Asterisk*

Case

Mars looks very bright in this picture. Was Mars actually close to Earth when this picture was taken? Or does Mars look so bright because it was just so much brighter than the tiny little comet? According to Stellarium, Mars was at mag 0.87 and 1.632 AU distance, at that time. Mars can be at mag -2...

Case

Amazing how far one can look in this image. The atmosphere must have been exceptionally clear that day? Beautiful.

Case

The reddish nebulosity is almost absent in DDS imaging (3 filters: 3950–5400, 6300–6900, 6950–9000 Å), which has a few wavelength gaps that I guess is significant to that dust.

Case

You have to look hard to recognize NGC 2170 in other semi wide field images, but here in today’s APOD image it looks deep, busy and impressive. https://apod.nasa.gov/apod/ap190821.html https://apod.nasa.gov/apod/ap151123.html Nice to see the nebulae that may get less attention than others. The Unico...

Case

The Discuss link currently goes to August 18 unfortunately.

Case

I just checked Wikipedia. According to Wikipedia, the Ghost of Jupiter is 1,400 light-years away. The source for the Wiki is an older APOD. The cited distance on that APOD was from what appears to be a 1995 (!) article . Queue 2019 Gaia , for the new distance link (2019), as the parallax is good en...

Case

https://www.youtube.com/watch?v=fjYuw6zWk_Y Still confused by parsecs … So was George Lucas . :wink: “It’s the ship that made the Kessel Run in less than 12 parsecs.” Although the filmmaker later tried to justify his error with an alternate explanation (finding a dangerous shortcut route, making it...

Case

Ann wrote: ↑Tue Jun 04, 2019 3:11 pmI read some place that when plate tectonics ceases on the Earth, the oceans will relatively soon begin to disappear, too.

If you can, please explain that causality.

Case

According to the not-too-precise parallax measurements of Hipparcos, the distance to HD 214710 is about 700 light-years. Gaia measured the parallax too, resulting in an even closer 626 ±13 lightyears. Gaia DR2 Basic search: ‘HD 214710’ resolved as source_id 2279611002534410496 at ra 339.30477079621...

Case

From NatGeo : Ten biggest known hits, in order of age: Vredefort Crater, South Africa. 2 billion years ago. 190 km wide. Sudbury Basin, Canada. 1.8 billion years ago. 130 km wide. Acraman Crater, Australia. 580 million years ago. 90 km wide. Woodleigh Crater, Australia. 364 million years ago. 120 km...

Case

The ESO video called it “superheated gas and dust”. Are we seeing (the bright parts of) the accretion disk here? Does such a disk go all the way up to the event horizon?
Why is “the shadow” of the black hole not the same as event horizon?

Case

Dr. Sean Raymond, University of Colorado, once said that 15 Jupiters is about the limit. Any larger (heavier) and they start fusion like a brown dwarf.

Case

Also, the Discuss link on the APOD page currently points to yesterday’s forum thread.

Case

Click to play embedded YouTube video.

So long, and thanks for all the fish.

Case

Did SpaceX time it for noctilucent vapor, or what? I don’t recall these light shows from pre-2010 launches …

Case

Click to play embedded YouTube video.

cmo55 wrote: ↑Sun Oct 07, 2018 6:51 pmremember seeing 'power of ten' as a child.

Thank you Charles and Ray Eames.

Case

I notice Vega (located at 10^9.6 in the scale) is wobbly in the animation. Being wobbly doesn’t point to varying brightness, or bulging at the equator, or a debris cloud, which are known/implied characteristics of Vega.

Case

What is less apparent night-to-night is that the Moon's apparent size changes slightly, and that a slight wobble called a libration occurs as the Moon progresses along its elliptical orbit. The Wiki describes nicely why the wobble is a perceived oscillation from our vantage point. I do wonder how i...

Case

I went to the fields outside the city for an unobscured view of the event, and was pleasantly surprised by the many other cars that had stopped on the side of the small roads, for apparently the same reason as I had come for. Possibly the weekend and summer holidays created an opportunity for more p...

Case

Often we see purple parts of the aurora below the green (and red on top), but here we see purple above the green. I suspect that this is because the top part or the aurora is illuminated by sunlight, so we see some scattering towards the blue. Very special!

Case

Ann wrote: ↑Sun Jun 17, 2018 5:52 amBecause it's true that Mars will be quite close and bright this summer and fall, isn't it?

Mars will be at opposition on Fri, 27 Jul 2018 at 05:07 UTC.

Case

As Mr Tyson often likes to point out, astronomers call it as they see em, unlike other sciences. No new words, or foreign words, just comparing the discovery to known properties by making a comparison. E.g.: very big reddish star: red giant; very small galaxy: dwarf galaxy; compact star predominantl...

Case

The link for Matt Russo has more of these wonderful tunes that link astronomy with music.
The song ‘Return to Earth’ by his band Rvnners is pretty cool, too.

Case

If you get a change to have a look for yourself, the best opportunity around this time of year is in the early hours (around 4 a.m., before dawn) in the East. You’ll find it in between Beta and Gamma Lyrae.

: Stellarium-chart for Michigan, this week, 4 a.m. Here, Vega is 60° up; M57 is 55° up.

Case

Finally, just barely visible to the unaided eye but quite striking here by camera is Barnard's Loop. I’ve read someone claim: “Using a nebular filter held up to the naked eye can pop out several nebulae. It certainly pops the NA nebula, the Rosette, Barnard's Loop, California Nebula.” I’ve never th...

Starship Asterisk*

Search found 608 matches

Re: APOD: The Day After Mars (2019 Nov 01)

Re: APOD: Planet Earth at Blue Hour (2019 Oct 11)

Re: APOD: NGC 2170: Angel Nebula Still Life (2019 Aug 26)

Re: APOD: NGC 2170: Angel Nebula Still Life (2019 Aug 26)

Re: APOD: Leaving Earth (2019 Aug 25)

Re: APOD: The Ghost of Jupiter's Halo (2019 Jul 11)

Re: APOD: Carina Nebula Panorama from Hubble (2019 Jun 23)

Re: APOD: SEIS: Listening for Marsquakes (2019 Jun 04)

Re: APOD: Lynds Dark Nebula 1251 (2019 May 31)

Re: APOD: Manicouagan Impact Crater from Space (2019 May 02)

Re: APOD: First Horizon-Scale Image of a Black... (2019 Apr 11)

Re: FAPESP: Evidence of a Planet with a Mass 13 Times Jupiter's

Re: APOD: Ultima Thule Rotation Gif (2019 Jan 04)

Re: APOD: Swimming on Jupiter (2018 Dec 14)

Re: APOD: The Falcon 9 Nebula (2018 Oct 12)

Re: APOD: The Scale of the Universe - Interactive (2018 Oct 07)

Re: APOD: The Scale of the Universe - Interactive (2018 Oct 07)

Re: APOD: Lunations (2018 Sep 12)

Re: APOD: Lunar Eclipse over Rio (2018 Jul 30)

Re: APOD: Northern Lights and Noctilucent Clouds (2018 Jun 21)

Re: APOD: Mars Engulfed (2018 Jun 17)

Re: APOD: A Plurality of Singularities at the... (2018 May 12)

Re: APOD: Play Saturn's Rings Like a Harp (2018 Apr 24)

Re: APOD: M57: The Ring Nebula (2018 Apr 17)

Re: APOD: Camera Orion (2018 Mar 21)