APOD: Moon in the Hyades (2018 Apr 20)

Comments and questions about the APOD on the main view screen.
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APOD: Moon in the Hyades (2018 Apr 20)

Post by APOD Robot » Fri Apr 20, 2018 4:07 am

Image Moon in the Hyades

Explanation: Have you seen the Moon lately? On April 18, its waxing sunlit crescent moved through planet Earth's night across a background of stars in the Hyades. Anchored by bright star Aldebaran, the nearby, V-shaped star cluster and complete lunar orb appear in this telephoto image. The engaging skyview is actually digitally composed from a series of varying exposures. Recorded in 1/60th of a second, the shortest in the series captures the Moon's bright crescent in sharp detail. Longer exposures, ranging up to 15 seconds, capture fainter background stars as well as earthshine, visible to the eye as the earthlit lunar night side.

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Ann
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Re: APOD: Moon in the Hyades (2018 Apr 20)

Post by Ann » Fri Apr 20, 2018 7:36 am

Neither the Moon nor the Hyades belong to my favorite astronomical objects. They are too nearby and "too yellow" for me.

So a conjunction of the Moon and the Hyades wouldn't normally excite me too much. But Jerry Lodriguss is one of my favorite astrophotographers, and I would probably post a lot of Lodriguss pictures here if Jerry did not guard his copyright to his pictures so carefully - as he has every right to do.

What I particularly like about today's APOD is how it "shrinks the size of the stars" by reducing the halos around them, thereby reminding us that even in a cluster like the Hyades, the actual distances between the stars are enormous. And because the very young Moon is not too bright, we can appreciate the the general size on our skies of the Hyades and compare it with the size on the sky of the Moon. The bright Earthshine on the Moon emphasizes its spherical size and really gives it a "body".

And I, of course, appreciate the bright colors of the stars of the Hyades! :D

Ann
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Sa Ji Tario

Re: APOD: Moon in the Hyades (2018 Apr 20)

Post by Sa Ji Tario » Fri Apr 20, 2018 11:33 am

To say the texts, the Hiades are older than the Pleiades and also were not born from the same molecular cloud (the Pleiades is said to be the Orion nebula) and at the end they have different movements in space. My question, is this like this? )

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Re: APOD: Moon in the Hyades (2018 Apr 20)

Post by De58te » Fri Apr 20, 2018 11:42 am

I don't mind seeing pictures of the Moon when they are sharper then what my usual nearsighted eyes see, and it is nice to see a rare picture of Aldebaran. How many times does Aldebaran appear in APOD photos? Nice to also label Gamma, Delta, and Epsilon Tauri, but what Greek sign is (-)? Theta? Also what is point 63 on the Moon's limb supposed to mean?

Sa Ji Tario

Re: APOD: Moon in the Hyades (2018 Apr 20)

Post by Sa Ji Tario » Fri Apr 20, 2018 12:05 pm

De58te
In terms of magnitude, when the Greek letters end, the Arabic numbers begin, the larger the less brightness (if that is your concern)

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Re: APOD: Moon in the Hyades (2018 Apr 20)

Post by CURRAHEE CHRIS » Fri Apr 20, 2018 1:05 pm

I really like this picture- it helps amateurs like myself identify objects in the sky better.

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Re: APOD: Moon in the Hyades (2018 Apr 20)

Post by neufer » Fri Apr 20, 2018 1:30 pm

Click to play embedded YouTube video.
Ann wrote:
Fri Apr 20, 2018 7:36 am

Neither the Moon nor the Hyades belong to my favorite astronomical objects. They are too nearby and "too yellow" for me.

What I particularly like about today's APOD is how it "shrinks the size of the stars" by reducing the halos around them, thereby reminding us that even in a cluster like the Hyades, the actual distances between the stars are enormous. And because the very young Moon is not too bright, we can appreciate the the general size on our skies of the Hyades and compare it with the size on the sky of the Moon. The bright Earthshine on the Moon emphasizes its spherical size and really gives it a "body".
Art Neuendorffer

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Ann
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Re: APOD: Moon in the Hyades (2018 Apr 20)

Post by Ann » Fri Apr 20, 2018 3:26 pm

Sa Ji Tario wrote:
Fri Apr 20, 2018 11:33 am
To say the texts, the Hiades are older than the Pleiades and also were not born from the same molecular cloud (the Pleiades is said to be the Orion nebula) and at the end they have different movements in space. My question, is this like this? )
Orion and the Pleiades, with the Hyades and Aldebaran between them.
Photo: Wikisky.
No, the Pleiades are not the Orion Nebula. As you can see in the picture at left, the Pleiades and Orion are relatively far apart. The Orion Nebula is the yellowish object that you can see below Orion's Belt in the picture.

According to Wikipedia, the estimated age of the Hyades is 625 million years. That is fairly young, and it is much, much younger than our Sun, which is some 4.5 billion years old or so. Nevertheless, the Hyades cluster is so old that all its O- and B-type stars have run through their entire life cycle and ended up as tiny, faint white dwarfs. The brightest stars in the Hyades are yellow-orange K-type giants and white to faintly bluish-white A-type main sequence stars.

The Pleiades are younger. Their estimated age is about 100 million years. The brightest stars in the Pleiades are all blue stars, which is a sure sign of youth. In the Pleiades, the blue stars belong to spectral class B. These stars are hot and blue, but nowhere near as hot and blue as O-type stars.

The Orion Nebula is powered by a small group of extremely young stars, less than a million years old. The brightest and hottest of these stars is Theta 1-C Orionis, a blisteringly hot and bright O-type star.

Ann
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Tir

Re: APOD: Moon in the Hyades (2018 Apr 20)

Post by Tir » Fri Apr 20, 2018 8:54 pm

Waste of APOD. Again.

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Re: APOD: Moon in the Hyades (2018 Apr 20)

Post by Boomer12k » Sat Apr 21, 2018 12:57 am

I saw it last night, got out the scopes at two different times. Of course The Moon was not in the Hyades at that time...as this was on the 18th...

Celestron Evolution 6...Around 8:30 I could see The Moon. The craters around the crescent were well shadowed, and looked great.
The Meade LX-90 8inch...Around 12:30: I saw Jupiter with 4 moons, and very nice cloud bands. Tried out many eyepieces and Yellow filter and a Blue...Also some Globulars. M13, M05, M92...I think. Cold, but not bad with a good jacket.
Today is bright but overcast, next clear night might be Sunday...but many more coming soon!!!! Hope to take pictures of Jupiter with both scopes to compare...

So, get out where you can and enjoy!!

One of my "Crescent Lunar Limb" images from 2017...
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