<p>The number 10 at the mark across the path means that the occultation is expected to occur there at 1:10 UTC (4:40 Iran time).</p>
<p>For this occultation, the star's apparent angular diameter is somewhat larger than the asteroid's.
Between the dot-dashed lines along the middle of the path, the occultation should be annular.
An observer there can expect a light curve resembling the example at upper right.</p>
<p>Farther off the centerline, the solid lines indicate where the edge of the penumbra is expected to pass.
From there, an observer would see little if any dimming of Betelgeuse.
Just outside those, the dashed lines represent a 1σ error estimate.
An observer outside those lines will likely see no effect.
The curve inside the penumbral band is just 40°N latitude.</p>
<p>The Japanese page also links to <a href="http://www.hal-astro-lab.com/asteroid/20231212_Betelgeuse_Map.html" rel="noreferrer">an interactive map</a>.
Here is <a href="https://www.asteroidoccultation.com/2023_12/1212_319_82912.htm" rel="noreferrer">another forecast</a> in English.</p>
<p>Other asteroid occultations may be easier to observe from your region.
To search for those, <a href="https://occultations.org/observing/software/" rel="noreferrer">IOTA recommends</a> the Windows applications Occult or OccultWatcher.</p>

CC BY-SA 4.0
2023-06-15T18:52:38.037Z
Sighs. Other asteroid occultations in my region are for stars which aren't visible to the naked eye. I saw a forecast of such occultations in the South West Asia.
Snack Exchange
CC BY-SA 4.0
2023-06-16T00:40:31.060Z
With an annular occultation I think the star will still shine and no changes are visible through the naked eyes. Am I right?
Snack Exchange
CC BY-SA 4.0
2023-06-16T02:00:23.423Z
@SnackExchange In this case ~37% of the star's disk would shine past the asteroid, so it would appear to dim by about 1 magnitude.
Mike G
CC BY-SA 4.0
2023-06-16T02:19:28.200Z
But doesn't the asteroid have an angular diameter of about 0.05 arcsecond just like Betelgeuse? look at [this](https://memim.com/319-leona.html) for more information. I don't know the distance of the asteroid from the Earth at the time of the occultation. But may be the site is right?!
Snack Exchange
CC BY-SA 4.0
2023-06-16T02:37:29.660Z
The chart gives the diameters of the star (48 milli-arcseconds) and asteroid (38 mas). The magnitude drop is only 1.1 magnitude which may not be obvious to an inexperienced observer. Note that the path may be updated in the days before the event, so the path could move into Iran or farther away.
JohnHoltz
CC BY-SA 4.0
2023-06-19T18:14:42.843Z
In the Wikipedia page of 319 Leona it's stated that the star will get dimmed by about 3 magnitudes.
Snack Exchange
CC BY-SA 4.0
2023-06-20T19:56:46.673Z
@SnackExchange That would be the result if the asteroid covers ~94% of the star. Photometry of this occultation may help refine the size estimate.
Mike G
CC BY-SA 4.0
2023-06-20T23:25:30.707Z
@MikeG I have found an exact amount of magnitude drop: It's 2.89, look at [this](https://www.asteroidoccultation.com/2023_12/1212_319_82912_Summary.txt) and [this](https://www.asteroidoccultation.com/2023_12/1212_319_82912_Map.gif)
Snack Exchange
CC BY-SA 4.0
2023-06-20T23:29:32.843Z
In the summary text it's stated that the shadow moves at a speed of $10.6604$ km/s and the occultation lasts $11.62$ s. So does it mean the apparent diameter of the star is $123.873848$ km?
Snack Exchange
CC BY-SA 4.0
2023-06-21T03:20:12.503Z
@SnackExchange The 2.9 magnitude drop estimate is based on a diameter of 61±3 km. [JPL SBDB](https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=319) says Leona is 49.9±0.5 km. Which is correct?
Mike G
CC BY-SA 4.0
2023-06-21T03:48:29.877Z
@MikeG The Wikipedia article for Leona also lists 5 different amounts for its diameter from 5 different sources.
Snack Exchange
CC BY-SA 4.0
2023-06-15T17:59:21.983Z
2023-06-15T17:59:21.983Z
Mike G
<p>I was looking at the Wikipedia page for <a href="https://en.m.wikipedia.org/wiki/319_Leona#:%7E:text=On%2012%20December%202023%20Leona,as%20seen%20from%20southern%20Europe." rel="nofollow noreferrer">319 Leona</a> and I got excited to know that it will occult the bright star Betelgeuse on December 12, 2023 (It's predicted with the use of Solex application):</p>
<blockquote>
<p>On 12 December 2023 at about 01:09–01:27 UT, Leona will occult Betelgeuse as seen from southern Europe, Turkey, Greece and Sicily. The 14th magnitude asteroid will occult Betelgeuse (block or reduce the light) for about 12 seconds. Betelgeuse is expected to dim by about 3 magnitudes. Light curve studies of the event may help understand the distribution of brightness over the disk of Betelgeuse.</p>
</blockquote>
<p>Then I searched to find the map of this occultaion and I found <a href="http://www.hal-astro-lab.com/asteroid/231212Betelgeuse.html" rel="nofollow noreferrer">this</a>. Of course, the webpage is in Japanese. So I translated it.</p>
<p>Well, the world map was very hard to find if the occultation is visible in Iran or not. So I clicked on a link to a map of Turkey which Iran was in it as well.</p>
<p>From there I found that a little of Iran's soil near the border with Azerbaijan is in the outernmost part of the asteroid's shadow.</p>
<p>It is obvious that people in central Azerbaijan can see the occultation with no problem (unless there is a bad weather). But what about Iran? Can people from the Azerbaijan-Iran borderline see a good occultation as well?</p>
<p>Well, I am Iranian myself and I don't want to miss this rare opportunity :(</p>
<p>Also, if you can help me to determine the exact UTC time the shadow reaches Azerbaijan-Iran border it will be very appreciated.</p>
<p><a href="https://i.sstatic.net/uOpLi.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/uOpLi.png" alt="With Iran's name labeled" /></a></p>

<asteroids><betelgeuse><occultation><app>
How will the 2023 occultation of Betelgeuse be seen from Iran?
Snack Exchange
# How will the 2023 occultation of Betelgeuse be seen from Iran?

(Asked by: username_0 on 2023-06-15)

I was looking at the Wikipedia page for [319 Leona](https://en.m.wikipedia.org/wiki/319_Leona#:%7E:text=On%2012%20December%202023%20Leona,as%20seen%20from%20southern%20Europe.) and I got excited to know that it will occult the bright star Betelgeuse on December 12, 2023 (It's predicted with the use of Solex application):

> On 12 December 2023 at about 01:09–01:27 UT, Leona will occult Betelgeuse as seen from southern Europe, Turkey, Greece and Sicily. The 14th magnitude asteroid will occult Betelgeuse (block or reduce the light) for about 12 seconds. Betelgeuse is expected to dim by about 3 magnitudes. Light curve studies of the event may help understand the distribution of brightness over the disk of Betelgeuse.

Then I searched to find the map of this occultaion and I found [this](http://www.hal-astro-lab.com/asteroid/231212Betelgeuse.html). Of course, the webpage is in Japanese. So I translated it.

Well, the world map was very hard to find if the occultation is visible in Iran or not. So I clicked on a link to a map of Turkey which Iran was in it as well.

From there I found that a little of Iran's soil near the border with Azerbaijan is in the outernmost part of the asteroid's shadow.

It is obvious that people in central Azerbaijan can see the occultation with no problem (unless there is a bad weather). But what about Iran? Can people from the Azerbaijan-Iran borderline see a good occultation as well?

Well, I am Iranian myself and I don't want to miss this rare opportunity :(

Also, if you can help me to determine the exact UTC time the shadow reaches Azerbaijan-Iran border it will be very appreciated.

[![With Iran's name labeled](https://i.sstatic.net/uOpLi.png)](https://i.sstatic.net/uOpLi.png)

**Tags:** asteroids, betelgeuse, occultation, app


---

## 1 answers

### Answer by username_1 on 2023-06-15. Score: 5 | Accepted answer

The number 10 at the mark across the path means that the occultation is expected to occur there at 1:10 UTC (4:40 Iran time).

For this occultation, the star's apparent angular diameter is somewhat larger than the asteroid's.
Between the dot-dashed lines along the middle of the path, the occultation should be annular.
An observer there can expect a light curve resembling the example at upper right.

Farther off the centerline, the solid lines indicate where the edge of the penumbra is expected to pass.
From there, an observer would see little if any dimming of Betelgeuse.
Just outside those, the dashed lines represent a 1σ error estimate.
An observer outside those lines will likely see no effect.
The curve inside the penumbral band is just 40°N latitude.

The Japanese page also links to [an interactive map](http://www.hal-astro-lab.com/asteroid/20231212_Betelgeuse_Map.html).
Here is [another forecast](https://www.asteroidoccultation.com/2023_12/1212_319_82912.htm) in English.

Other asteroid occultations may be easier to observe from your region.
To search for those, [IOTA recommends](https://occultations.org/observing/software/) the Windows applications Occult or OccultWatcher.

> **Comments:**
> **username_0**: Sighs. Other asteroid occultations in my region are for stars which aren't visible to the naked eye. I saw a forecast of such occultations in the South West Asia.  
> **username_0**: With an annular occultation I think the star will still shine and no changes are visible through the naked eyes. Am I right?  
> **username_1**: @SnackExchange In this case ~37% of the star's disk would shine past the asteroid, so it would appear to dim by about 1 magnitude.  
> **username_0**: But doesn't the asteroid have an angular diameter of about 0.05 arcsecond just like Betelgeuse? look at [this](https://memim.com/319-leona.html) for more information. I don't know the distance of the asteroid from the Earth at the time of the occultation. But may be the site is right?!  
> **username_2**: The chart gives the diameters of the star (48 milli-arcseconds) and asteroid (38 mas). The magnitude drop is only 1.1 magnitude which may not be obvious to an inexperienced observer. Note that the path may be updated in the days before the event, so the path could move into Iran or farther away.  
> **username_0**: In the Wikipedia page of 319 Leona it's stated that the star will get dimmed by about 3 magnitudes.  
> **username_1**: @SnackExchange That would be the result if the asteroid covers ~94% of the star. Photometry of this occultation may help refine the size estimate.  
> **username_0**: @MikeG I have found an exact amount of magnitude drop: It's 2.89, look at [this](https://www.asteroidoccultation.com/2023_12/1212_319_82912_Summary.txt) and [this](https://www.asteroidoccultation.com/2023_12/1212_319_82912_Map.gif)  
> **username_0**: In the summary text it's stated that the shadow moves at a speed of $10.6604$ km/s and the occultation lasts $11.62$ s. So does it mean the apparent diameter of the star is $123.873848$ km?  
> **username_1**: @SnackExchange The 2.9 magnitude drop estimate is based on a diameter of 61±3 km. [JPL SBDB](https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=319) says Leona is 49.9±0.5 km. Which is correct?  
> **username_0**: @MikeG The Wikipedia article for Leona also lists 5 different amounts for its diameter from 5 different sources.  

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