<p>I suspect that that is simply a statement about where you would have the best visibility of each meteor shower.  The name of each shower tells you where the <a href="https://en.wikipedia.org/wiki/Radiant_(meteor_shower)" rel="nofollow noreferrer">radiant</a> is, the point in the sky from which the trails of the meteors appear to originate.   Perseus in the northern sky (with the specific radiant point of the <a href="https://en.wikipedia.org/wiki/Perseids" rel="nofollow noreferrer">Perseids</a> at +58 degrees declination), while Aquarius is farther south (with the radiant of the <a href="https://en.wikipedia.org/wiki/Southern_Delta_Aquariids" rel="nofollow noreferrer">delta Aquariids</a> at about -16 degrees declination), so a northern observer would have the Perseids radiant higher in the sky and would see more of those meteors, and vice versa for a southern observer and the delta Aquariids.</p>
<p>Since the meteors go in all directions from the radiant, at least <em>some</em> from either shower would be visible for observers over a large range of latitudes, but you’d see the most if the radiant is high in your sky.</p>
<p>Edit: this nice image from spaceweather.com shows clearly <em>why</em> the radiants have their respective locations:</p>
<p><img src="https://www.spaceweather.com/images2015/31jul15/orbits.gif" alt="" /></p>
<p>(From <a href="https://www.spaceweather.com/archive.php?view=1&amp;day=31&amp;month=07&amp;year=2015" rel="nofollow noreferrer">spaceweather.com</a>, linked from <a href="https://skyandtelescope.org/astronomy-news/observing-news/plan-for-the-perseids/" rel="nofollow noreferrer">Sky &amp; Telescope</a>.)</p>
<p>These are reconstructed orbits of fireballs seen as part of these showers.  The light green are the delta Aquariids, and the darker green / teal are the Perseids.  You can see that they have very different inclinations where they intersect Earth, so they appear to originate from different directions in our sky.</p>

CC BY-SA 4.0
2020-07-24T14:12:55.903Z
`+1` To make this complete, [Comet Swift-Tuttle](https://en.wikipedia.org/wiki/Comet_Swift%E2%80%93Tuttle) has a nearly circular orbit of about 1 AU but an inclination of **113.45°** which is just about what it would have to be (double) to push the Perseids' radiant to a declination of +58°
uhoh
CC BY-SA 4.0
2020-07-25T05:58:05.083Z
thinking about this further, I've just asked [How to calculate the position of a meteor shower's radiant point based on it's associated comet's orbit?](https://astronomy.stackexchange.com/q/37134/7982)
uhoh
CC BY-SA 4.0
2020-07-24T12:42:52.687Z
2020-07-24T13:06:41.223Z
2020-07-24T13:06:41.223Z
Eric Jensen
<p>In the video <a href="https://youtu.be/RbZ13TEHuOs?t=328" rel="nofollow noreferrer">How to spot Comet NEOWISE, plus the largest 3D map of the Universe | Night Sky News July 20</a> after <code>05:28</code> Dr. Becky (Smethurst, Oxford astrophysicist) says:</p>
<blockquote>
<p>…and it just so happens that we’ll be passing through the debris trail of two of the comets whilst comet NEOWISE is going to be visible in the sky, and so that’s going to cause to very popular meteor showers. There’s the Delta Aquariids meteor shower at the end of July, and then the Perseids meteor shower mid-August time.</p>
<p>And the Perseids meteor shower is just <em>hands down</em> the BEST meteor shower of the year. There’s something like sixty meteors per hour during its peak which this year is going to be the 12th of August.</p>
<p>Now the Delta Aquariidss are probably more like fifteen to twenty meteors per hour, so not quite as spectacular as the Perseids, <strong>but the Delta Aquariids really are more for the southern hemisphere where the Perseids is really going to be for the Northern hemisphere.</strong></p>
</blockquote>
<p><strong>Question:</strong> Why are Delta Aquariids for the southern hemisphere while the Perseids are for the north? The Earth is moving along its orbit at 29 km/sec in both cases, why the big difference?</p>
<p><strong>note:</strong> there are notes below the video that you might find helpful if looking for comet NEOWISE.</p>

CC BY-SA 4.0
2020-07-24T12:29:26.947Z
The apparent location of the meteor radiants depend on their orbit, see e.g.  https://in-the-sky.org/news.php?id=20200423_10_100  and https://ase.tufts.edu/cosmos/view_picture.asp?id=1305 for some nice illustrations. So it is just a matter of geometry if they are visible on the northern or southern hemisphere.
samcarter_is_at_topanswers.xyz
CC BY-SA 4.0
2024-08-11T06:54:07.530Z
Really, it’s because the perseids produce more meteors overall but they hit earth from such a direction that the majority hit the northern hemisphere
Harrychink
<observational-astronomy><amateur-observing><comets><meteor-shower>
Why are Delta Aquariids "for the southern hemisphere" while the Perseids are "for the north"?
uhoh
# Why are Delta Aquariids "for the southern hemisphere" while the Perseids are "for the north"?

(Asked by: username_0 on 2020-07-24)

In the video [How to spot Comet NEOWISE, plus the largest 3D map of the Universe | Night Sky News July 20](https://youtu.be/RbZ13TEHuOs?t=328) after `05:28` Dr. Becky (Smethurst, Oxford astrophysicist) says:

> …and it just so happens that we’ll be passing through the debris trail of two of the comets whilst comet NEOWISE is going to be visible in the sky, and so that’s going to cause to very popular meteor showers. There’s the Delta Aquariids meteor shower at the end of July, and then the Perseids meteor shower mid-August time.
>
> And the Perseids meteor shower is just *hands down* the BEST meteor shower of the year. There’s something like sixty meteors per hour during its peak which this year is going to be the 12th of August.
>
> Now the Delta Aquariidss are probably more like fifteen to twenty meteors per hour, so not quite as spectacular as the Perseids, **but the Delta Aquariids really are more for the southern hemisphere where the Perseids is really going to be for the Northern hemisphere.**

**Question:** Why are Delta Aquariids for the southern hemisphere while the Perseids are for the north? The Earth is moving along its orbit at 29 km/sec in both cases, why the big difference?

**note:** there are notes below the video that you might find helpful if looking for comet NEOWISE.

**Tags:** observational-astronomy, amateur-observing, comets, meteor-shower
> **Comments:**
> **username_1**: The apparent location of the meteor radiants depend on their orbit, see e.g.  https://in-the-sky.org/news.php?id=20200423_10_100  and https://ase.tufts.edu/cosmos/view_picture.asp?id=1305 for some nice illustrations. So it is just a matter of geometry if they are visible on the northern or southern hemisphere.  
> **username_2**: Really, it’s because the perseids produce more meteors overall but they hit earth from such a direction that the majority hit the northern hemisphere  

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## 1 answers

### Answer by username_3 on 2020-07-24. Score: 2 | Accepted answer

I suspect that that is simply a statement about where you would have the best visibility of each meteor shower. The name of each shower tells you where the [radiant](https://en.wikipedia.org/wiki/Radiant_(meteor_shower)) is, the point in the sky from which the trails of the meteors appear to originate. Perseus in the northern sky (with the specific radiant point of the [Perseids](https://en.wikipedia.org/wiki/Perseids) at +58 degrees declination), while Aquarius is farther south (with the radiant of the [delta Aquariids](https://en.wikipedia.org/wiki/Southern_Delta_Aquariids) at about -16 degrees declination), so a northern observer would have the Perseids radiant higher in the sky and would see more of those meteors, and vice versa for a southern observer and the delta Aquariids.

Since the meteors go in all directions from the radiant, at least *some* from either shower would be visible for observers over a large range of latitudes, but you’d see the most if the radiant is high in your sky.

Edit: this nice image from spaceweather.com shows clearly *why* the radiants have their respective locations:

![](https://www.spaceweather.com/images2015/31jul15/orbits.gif)

(From [spaceweather.com](https://www.spaceweather.com/archive.php?view=1&day=31&month=07&year=2015), linked from [Sky & Telescope](https://skyandtelescope.org/astronomy-news/observing-news/plan-for-the-perseids/).)

These are reconstructed orbits of fireballs seen as part of these showers. The light green are the delta Aquariids, and the darker green / teal are the Perseids. You can see that they have very different inclinations where they intersect Earth, so they appear to originate from different directions in our sky.

> **Comments:**
> **username_0**: `+1` To make this complete, [Comet Swift-Tuttle](https://en.wikipedia.org/wiki/Comet_Swift%E2%80%93Tuttle) has a nearly circular orbit of about 1 AU but an inclination of **113.45°** which is just about what it would have to be (double) to push the Perseids' radiant to a declination of +58°  
> **username_0**: thinking about this further, I've just asked [How to calculate the position of a meteor shower's radiant point based on it's associated comet's orbit?](https://astronomy.stackexchange.com/q/37134/7982)  

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