<p>As a disclaimer to start with, I don't know anything about travel in and around Asia, so I'm really only considering the factors impacting observation conditions.</p>
<p>I'd focus on locating a decently dark sky area that you can reach as a first concern. That can be difficult if you have to travel somewhere that you won't have a personal vehicle available, since places that are well served by public transit are typically well lit enough to be pretty washed out. Personally, I like to use <a href="https://www.lightpollutionmap.info/" rel="nofollow noreferrer">https://www.lightpollutionmap.info/</a> to find dark-sky locations, though there are a few other websites that do the same thing. A Bortle 3 sky is kind of the minimum for decent stargazing but darker is better, of course.</p>
<p>The closest approach of Apophis is between 21:00 and 23:00 UTC, and should be more or less directly overhead in the Taiwan area, but you're also at UTC+8, which puts the local time around 6 in the morning, which is basically dawn in April. Not good for viewing. You'll likely have to head west to get away from the sun, but the further you go, the lower Apophis will be in the sky.</p>
<p>There might be viable areas in western Indonesia, maybe somewhere on Sumatra, but you're still going to be fighting dawn there. I'm not sure how badly impacted you'd be.</p>
<p>Going a little further, most of India is pretty washed out, but Nepal or Tibet might be a viable destination, depending on what the flights cost and how weird China is going to be about people coming in from Taiwan. Both of them have wonky time zones -- Nepal is on a 45 minute offset from UTC, and Tibet operates on Beijing time despite being 2-3 hours earlier by the sun. That said, it should be 3-4am sidereal around there, if I did the math correctly. I don't know what the nighttime cloud conditions are in the mountains, but the monsoons don't start until summer, so it should be relatively clear I would think.</p>

CC BY-SA 4.0
2024-07-24T15:24:22.793Z
2024-07-25T14:53:18.257Z
2024-07-25T14:53:18.257Z
Darth Pseudonym
<p>This isn't a complete answer to your question, but it contains some relevant data.</p>
<p>According to JPL <a href="https://ssd.jpl.nasa.gov/horizons/" rel="nofollow noreferrer">Horizons</a>, the next close approach of Apophis to Earth occurs on 2029-Apr-13 21:45 UTC, with a distance to the centre of the Earth of ~38,000 km. Here's a Horizons <a href="https://ssd.jpl.nasa.gov/api/horizons.api?format=text&amp;EPHEM_TYPE=V&amp;CSV_FORMAT=YES&amp;VEC_TABLE=6&amp;COMMAND=99942&amp;CENTER=%40399&amp;START_TIME=%272029-Apr-13+15%3A45+UT%27&amp;STOP_TIME=%272029-Apr-14+3%3A45%27&amp;STEP_SIZE=15m" rel="nofollow noreferrer">query URL</a> for that data.</p>
<p>The SPICE / Horizons ID of Apophis is <code>99942;</code>. The semicolon indicates that it's a minor body, but if you omit it, Horizons will <em>probably</em> figure out that you mean Apophis. ;) The current Horizons record for Apophis uses a solution dated 2023-Nov-06 14:29:44, based on 7364 observations spanning 2004-2021.</p>
<p>Please note that Horizons UTC calculations for future times assume that there will be no additional leap seconds.</p>
<p>The sidereal period of Apophis is ~0.88606 Julian years = 323.633 days. Its synodic period relative to Earth is almost exactly 2840 days, which is ~7.77536 years. That's very close to <span class="math-container">$7\frac79$</span>, so Apophis makes ~79 orbits of the Sun in 70 Earth years. However, its orbital pattern is not simple because it can get perturbed significantly when it approaches Earth (roughly every synodic period).</p>
<p>Here are some Horizons distance plots, created using a version of my distance script <a href="https://astronomy.stackexchange.com/a/49267/16685">here</a>. First, a plot covering a couple of synodic periods, from 2011 to 2035, with a 15 day timestep.
<a href="https://i.sstatic.net/9nEdgECK.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/9nEdgECK.png" alt="Apophis-Earth distance, 2011-2035" /></a>
Here's a zoom in on the 2029 close approach day, with a 15 minute timestep.
<a href="https://i.sstatic.net/2PU5y2M6.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/2PU5y2M6.png" alt="Apophis-Earth distance, 2029-Apr-13" /></a></p>
<p>At the close approach, its motion on the celestial sphere is quite rapid. Here's a <a href="https://ssd.jpl.nasa.gov/api/horizons.api?format=text&amp;COMMAND=99942%3B&amp;CENTER=500%40399&amp;START_TIME=%272029-Apr-13+18%3A45%27&amp;STOP_TIME=%272029-Apr-14+0%3A45%27&amp;STEP_SIZE=15m&amp;QUANTITIES=%272%2C31%27&amp;ANG_FORMAT=DEG&amp;APPARENT=AIRLESS&amp;OBJ_DATA=NO" rel="nofollow noreferrer">query URL</a> for its apparent RA &amp; declination, and its ecliptic longitude &amp; latitude. Here's an excerpt of the data:</p>
<pre><code>Target body name: 99942 Apophis (2004 MN4)        {source: JPL#218}
Center body name: Earth (399)                     {source: DE441}

Start time      : A.D. 2029-Apr-13 18:45:00.0000 UT
Stop  time      : A.D. 2029-Apr-14 00:45:00.0000 UT
Step-size       : 15 minutes

 Date__(UT)__HR:MN     R.A._(a-appar)_DEC.     ObsEcLon    ObsEcLat
*******************************************************************
 2029-Apr-13 18:45     183.38243 -12.60674  188.1568657 -10.2156039
 2029-Apr-13 19:00     181.44112 -11.13088  185.7877348  -9.6314894
 2029-Apr-13 19:15     179.24874  -9.43102  183.0931885  -8.9450247
 2029-Apr-13 19:30     176.75660  -7.46186  180.0104328  -8.1326043
 2029-Apr-13 19:45     173.90406  -5.16918  176.4634735  -7.1650665
 2029-Apr-13 20:00     170.61544  -2.49019  172.3618362  -6.0073351
 2029-Apr-13 20:15     166.79666   0.64331  167.6012046  -4.6193908
 2029-Apr-13 20:30     162.33220   4.29582  162.0684247  -2.9602272
 2029-Apr-13 20:45     157.08431   8.50866  155.6548916  -0.9974003
 2029-Apr-13 21:00     150.89870  13.26506  148.2834192   1.2751017
 2029-Apr-13 21:15     143.62488  18.44128  139.9513687   3.8113279
 2029-Apr-13 21:30     135.16292  23.76242  130.7822320   6.4908808
 2029-Apr-13 21:45     125.54398  28.80751  121.0583281   9.1227351
 2029-Apr-13 22:00     115.02249  33.10692  111.1957615  11.4935818
 2029-Apr-13 22:15     104.10586  36.30927  101.6495138  13.4418909
 2029-Apr-13 22:30      93.44242  38.30876   92.7946914  14.9061360
 2029-Apr-13 22:45      83.60540  39.23974   84.8536325  15.9178864
 2029-Apr-13 23:00      74.93077  39.36525   77.8953357  16.5602663
 2029-Apr-13 23:15      67.50340  38.95908   71.8802116  16.9274742
 2029-Apr-13 23:30      61.24124  38.24173   66.7116690  17.1019453
 2029-Apr-13 23:45      55.98827  37.36678   62.2740898  17.1471250
 2029-Apr-14 00:00      51.57522  36.43176   58.4543941  17.1084849
 2029-Apr-14 00:15      47.84819  35.49461   55.1517014  17.0173102
 2029-Apr-14 00:30      44.67787  34.58756   52.2801654  16.8946151
 2029-Apr-14 00:45      41.95962  33.72706   49.7685084  16.7543038
</code></pre>
<p>Incidentally, the closest approach of Apophis occurs during a New Moon. The Sun's longitude is ~24.24°, the Moon's longitude ranges from 22.80° to 25.77° over that time interval, and is ~24.28° at 21:45 UTC.</p>
<p>Here's a plot of the ecliptic longitude &amp; latitude of Apophis. Please note that the vertical &amp; horizontal scales are not equal! My lon-lat plotting script is <a href="https://astronomy.stackexchange.com/a/57281/16685">here</a>.</p>
<p><a href="https://i.sstatic.net/8Mz6Gm2T.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/8Mz6Gm2T.png" alt="Apophis, ecliptic lon &amp; lat, 2029-Apr-13" /></a></p>
<p>Here's a crude estimate of its magnitude. The magnitude script is <a href="https://astronomy.stackexchange.com/a/55178/16685">here</a>. Those bumps after 22:45 are probably algorithm artifacts due to rounding to the nearest whole number magnitude and then interpolating. Please see the Horizons manual for details.
<a href="https://i.sstatic.net/tCXXNbWy.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/tCXXNbWy.png" alt="Apophis magnitude, 2029-Aor-13" /></a></p>
<p>Here are a couple of speed plots, created using my script in <a href="https://space.stackexchange.com/a/61065/38535">this space.SE answer</a>.</p>
<p><a href="https://i.sstatic.net/GP6WiKhQ.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/GP6WiKhQ.png" alt="Apophis relative orbital speed" /></a></p>
<p><a href="https://i.sstatic.net/IYgM3d5W.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/IYgM3d5W.png" alt="Apophis ground track speed" /></a></p>
<hr />
<p>Finally, here are a couple of screenshots from 3D orbit plots, covering the timespan between the last close approach and the next one, 2021-Mar-6 to 2029-Apr-13. The inclination of the Apophis orbit is only ~3.34° (relative to the ecliptic, which is smaller than the Moon's mean inclination (~5.14°). But the 3D views still contain useful information.</p>
<p>In the first plot, which uses a 50 day timestep, Apophis is the same reddish shade that I've used in the above graphs, the Earth is blue, and the Sun is orange. The horizontal grey line from the Sun is the equinox direction. It appears that Apophis makes two close approaches to Earth's orbit, but the crossover in the upper part of the image occurs well below the ecliptic plane.</p>
<p><a href="https://i.sstatic.net/OlzB2Hr1.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/OlzB2Hr1.png" alt="Apophis &amp; Earth orbits" /></a></p>
<p>The following plot, which uses a 5 day timestep, shows the motion of Apophis relative to Earth. Apophis is coloured using a rainbow sequence. Earth is a pale bluish grey.</p>
<p><a href="https://i.sstatic.net/TCraRSJj.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/TCraRSJj.png" alt="Apophis orbit relative to Earth" /></a></p>
<p>The 3D plotting script is linked in the same answer as my magnitude plotting script.</p>

CC BY-SA 4.0
2024-07-24T00:05:03.510Z
"This isn't a complete answer..." I suggest the following, perhaps as a new answer to separate useful information from the cool-looking information: Choose a half-dozen locations on Earth's surface (Horizons allows lat/lon locations - you can even choose named locations like "Mars Florida" which always tricked me). For each location, plot altitude, azimuth and apparent magnitude for say a 12 hour window around 2029-Apr-13 21:45 UTC. Make the lines dashed during daylight or twilight and solid at night. Now THAT would be an actual partial answer to the question as asked; useful to sky watchers.
uhoh
CC BY-SA 4.0
2024-07-23T12:30:32.243Z
2024-07-23T12:39:23.207Z
2024-07-23T12:39:23.207Z
PM 2Ring
<p>This is a follow-up to <a href="https://astronomy.stackexchange.com/a/36084/7982">@usernumber's answer to <em>Has a near earth object in heliocentric orbit ever been bright enough to be visible to the unaided eye?</em></a></p>
<p>I'm not afraid it will hit me, so if I'm still alive in 2029 I'd like to go take a look - perhaps it will even do a little something interesting due to tidal effects of Earth's gravity gradient on it's potentially rubble-pile nature.</p>
<p>Amateur observing planning includes both a ground track map with day/night information and some basic meteorological expectations if we want to do more than read about it in <a href="https://www.cloudynights.com/" rel="nofollow noreferrer">cloudy nights</a> forums. So areas that historically have lots of clear nights in April are better than cloudy ones.</p>
<p>Baring any related international incidents, I will likely still be in Taiwan - so in addition to a global answer for all readers, advice for travelers in East Asia with tiny pocketbooks<sup>1</sup> will also be appreciated.</p>
<hr />
<p><sup>1</sup>those that can't fly a private jet or can't afford the medical insurance necessary to deal with catching something on a cruise ship</p>

CC BY-SA 4.0
2024-07-23T05:55:39.707Z
The closest approach is ~38,000 km on 2029-Apr-13 21:45 UTC https://ssd.jpl.nasa.gov/api/horizons.api?format=text&EPHEM_TYPE=V&CSV_FORMAT=YES&VEC_TABLE=6&COMMAND=99942&CENTER=%40399&START_TIME=%272029-Apr-13+15%3A45+UT%27&STOP_TIME=%272029-Apr-14+3%3A45%27&STEP_SIZE=15m
PM 2Ring
CC BY-SA 4.0
2024-07-23T18:18:33.910Z
Would one of the national parks in the Philippines be an option? Looking at https://www.lightpollutionmap.info, Taiwan seems like it's pretty washed out. You can get some Bortle 3 skies in like Shei Pa or Taroko, but if you want really dark sky you'll need to get off the island.  It looks like one of the little japanese islands to your east might work -- Iriomote or some such -- but those are probably really hard to get to without bouncing through Tokyo first.
Darth Pseudonym
CC BY-SA 4.0
2024-07-23T18:28:39.920Z
But that might put you pretty close to dawn at the nearest approach... yuck. You might need to be in Africa to have a decent view and ALSO a decently dark sky. Europe's light pollution is about as bad as Taiwan's.
Darth Pseudonym
CC BY-SA 4.0
2024-07-24T00:36:36.360Z
@DarthPseudonym now *that's an excellent partial answer!* Yes, without a car to drive up some mountain in the middle of the island, Taiwan is not so friendly to stargazers or meteor shower-watchers. Any place you can get off a train or bus will have plentyof light, and for some reason Taiwan now favors totally unshielded raw white-light, sideways-pointing LED street lighting. I've seen some staggeringly dark  and rich skies traveling around the smaller islands in Indonesia, even at low elevations, as you point out there should be similar places in the Philippines.
uhoh
CC BY-SA 4.0
2024-07-24T00:40:16.257Z
@DarthPseudonym This sounds like something that I should probably start doing a lot sooner than 2029! If you book ahead of time, these "local" flights (Taipei to East and Southeast Asia) can be surprisingly cheap as long as you follow the rules [1](https://travel.stackexchange.com/q/172341/59997), [2](https://travel.stackexchange.com/a/173725/59997) ;-)
uhoh
<amateur-observing><asteroids><prediction><99942-apophis>
Where should I go in April 2029 for the best chance of naked-eye observing of 99942 Apophis (2004 MN4)?
uhoh
# Where should I go in April 2029 for the best chance of naked-eye observing of 99942 Apophis (2004 MN4)?

(Asked by: username_0 on 2024-07-23)

This is a follow-up to [@usernumber's answer to *Has a near earth object in heliocentric orbit ever been bright enough to be visible to the unaided eye?*](https://astronomy.stackexchange.com/a/36084/7982)

I'm not afraid it will hit me, so if I'm still alive in 2029 I'd like to go take a look - perhaps it will even do a little something interesting due to tidal effects of Earth's gravity gradient on it's potentially rubble-pile nature.

Amateur observing planning includes both a ground track map with day/night information and some basic meteorological expectations if we want to do more than read about it in [cloudy nights](https://www.cloudynights.com/) forums. So areas that historically have lots of clear nights in April are better than cloudy ones.

Baring any related international incidents, I will likely still be in Taiwan - so in addition to a global answer for all readers, advice for travelers in East Asia with tiny pocketbooks1 will also be appreciated.

---

1those that can't fly a private jet or can't afford the medical insurance necessary to deal with catching something on a cruise ship

**Tags:** amateur-observing, asteroids, prediction, 99942-apophis

> **Comments:**
> **username_1**: The closest approach is ~38,000 km on 2029-Apr-13 21:45 UTC https://ssd.jpl.nasa.gov/api/horizons.api?format=text&EPHEM_TYPE=V&CSV_FORMAT=YES&VEC_TABLE=6&COMMAND=99942&CENTER=%40399&START_TIME=%272029-Apr-13+15%3A45+UT%27&STOP_TIME=%272029-Apr-14+3%3A45%27&STEP_SIZE=15m  
> **username_2**: Would one of the national parks in the Philippines be an option? Looking at https://www.lightpollutionmap.info, Taiwan seems like it's pretty washed out. You can get some Bortle 3 skies in like Shei Pa or Taroko, but if you want really dark sky you'll need to get off the island.  It looks like one of the little japanese islands to your east might work -- Iriomote or some such -- but those are probably really hard to get to without bouncing through Tokyo first.  
> **username_2**: But that might put you pretty close to dawn at the nearest approach... yuck. You might need to be in Africa to have a decent view and ALSO a decently dark sky. Europe's light pollution is about as bad as Taiwan's.  
> **username_0**: @DarthPseudonym now *that's an excellent partial answer!* Yes, without a car to drive up some mountain in the middle of the island, Taiwan is not so friendly to stargazers or meteor shower-watchers. Any place you can get off a train or bus will have plentyof light, and for some reason Taiwan now favors totally unshielded raw white-light, sideways-pointing LED street lighting. I've seen some staggeringly dark  and rich skies traveling around the smaller islands in Indonesia, even at low elevations, as you point out there should be similar places in the Philippines.  
> **username_0**: @DarthPseudonym This sounds like something that I should probably start doing a lot sooner than 2029! If you book ahead of time, these "local" flights (Taipei to East and Southeast Asia) can be surprisingly cheap as long as you follow the rules [1](https://travel.stackexchange.com/q/172341/59997), [2](https://travel.stackexchange.com/a/173725/59997) ;-)  

---

## 2 answers

### Answer by username_2 on 2024-07-24. Score: 2 | Accepted answer

As a disclaimer to start with, I don't know anything about travel in and around Asia, so I'm really only considering the factors impacting observation conditions.

I'd focus on locating a decently dark sky area that you can reach as a first concern. That can be difficult if you have to travel somewhere that you won't have a personal vehicle available, since places that are well served by public transit are typically well lit enough to be pretty washed out. Personally, I like to use <https://www.lightpollutionmap.info/> to find dark-sky locations, though there are a few other websites that do the same thing. A Bortle 3 sky is kind of the minimum for decent stargazing but darker is better, of course.

The closest approach of Apophis is between 21:00 and 23:00 UTC, and should be more or less directly overhead in the Taiwan area, but you're also at UTC+8, which puts the local time around 6 in the morning, which is basically dawn in April. Not good for viewing. You'll likely have to head west to get away from the sun, but the further you go, the lower Apophis will be in the sky.

There might be viable areas in western Indonesia, maybe somewhere on Sumatra, but you're still going to be fighting dawn there. I'm not sure how badly impacted you'd be.

Going a little further, most of India is pretty washed out, but Nepal or Tibet might be a viable destination, depending on what the flights cost and how weird China is going to be about people coming in from Taiwan. Both of them have wonky time zones -- Nepal is on a 45 minute offset from UTC, and Tibet operates on Beijing time despite being 2-3 hours earlier by the sun. That said, it should be 3-4am sidereal around there, if I did the math correctly. I don't know what the nighttime cloud conditions are in the mountains, but the monsoons don't start until summer, so it should be relatively clear I would think.


---

### Answer by username_1 on 2024-07-23. Score: 2

This isn't a complete answer to your question, but it contains some relevant data.
According to JPL Horizons, the next close approach of Apophis to Earth occurs on 2029-Apr-13 21:45 UTC, with a distance to the centre of the Earth of ~38,000 km. Here's a Horizons query URL for that data.
The SPICE / Horizons ID of Apophis is 99942;. The semicolon indicates that it's a minor body, but if you omit it, Horizons will probably figure out that you mean Apophis. ;) The current Horizons record for Apophis uses a solution dated 2023-Nov-06 14:29:44, based on 7364 observations spanning 2004-2021.
Please note that Horizons UTC calculations for future times assume that there will be no additional leap seconds.
The sidereal period of Apophis is ~0.88606 Julian years = 323.633 days. Its synodic period relative to Earth is almost exactly 2840 days, which is ~7.77536 years. That's very close to $7\frac79$, so Apophis makes ~79 orbits of the Sun in 70 Earth years. However, its orbital pattern is not simple because it can get perturbed significantly when it approaches Earth (roughly every synodic period).
Here are some Horizons distance plots, created using a version of my distance script here. First, a plot covering a couple of synodic periods, from 2011 to 2035, with a 15 day timestep.

Here's a zoom in on the 2029 close approach day, with a 15 minute timestep.

At the close approach, its motion on the celestial sphere is quite rapid. Here's a query URL for its apparent RA & declination, and its ecliptic longitude & latitude. Here's an excerpt of the data:
Target body name: 99942 Apophis (2004 MN4)        {source: JPL#218}
Center body name: Earth (399)                     {source: DE441}

Start time      : A.D. 2029-Apr-13 18:45:00.0000 UT
Stop  time      : A.D. 2029-Apr-14 00:45:00.0000 UT
Step-size       : 15 minutes

 Date__(UT)__HR:MN     R.A._(a-appar)_DEC.     ObsEcLon    ObsEcLat
*******************************************************************
 2029-Apr-13 18:45     183.38243 -12.60674  188.1568657 -10.2156039
 2029-Apr-13 19:00     181.44112 -11.13088  185.7877348  -9.6314894
 2029-Apr-13 19:15     179.24874  -9.43102  183.0931885  -8.9450247
 2029-Apr-13 19:30     176.75660  -7.46186  180.0104328  -8.1326043
 2029-Apr-13 19:45     173.90406  -5.16918  176.4634735  -7.1650665
 2029-Apr-13 20:00     170.61544  -2.49019  172.3618362  -6.0073351
 2029-Apr-13 20:15     166.79666   0.64331  167.6012046  -4.6193908
 2029-Apr-13 20:30     162.33220   4.29582  162.0684247  -2.9602272
 2029-Apr-13 20:45     157.08431   8.50866  155.6548916  -0.9974003
 2029-Apr-13 21:00     150.89870  13.26506  148.2834192   1.2751017
 2029-Apr-13 21:15     143.62488  18.44128  139.9513687   3.8113279
 2029-Apr-13 21:30     135.16292  23.76242  130.7822320   6.4908808
 2029-Apr-13 21:45     125.54398  28.80751  121.0583281   9.1227351
 2029-Apr-13 22:00     115.02249  33.10692  111.1957615  11.4935818
 2029-Apr-13 22:15     104.10586  36.30927  101.6495138  13.4418909
 2029-Apr-13 22:30      93.44242  38.30876   92.7946914  14.9061360
 2029-Apr-13 22:45      83.60540  39.23974   84.8536325  15.9178864
 2029-Apr-13 23:00      74.93077  39.36525   77.8953357  16.5602663
 2029-Apr-13 23:15      67.50340  38.95908   71.8802116  16.9274742
 2029-Apr-13 23:30      61.24124  38.24173   66.7116690  17.1019453
 2029-Apr-13 23:45      55.98827  37.36678   62.2740898  17.1471250
 2029-Apr-14 00:00      51.57522  36.43176   58.4543941  17.1084849
 2029-Apr-14 00:15      47.84819  35.49461   55.1517014  17.0173102
 2029-Apr-14 00:30      44.67787  34.58756   52.2801654  16.8946151
 2029-Apr-14 00:45      41.95962  33.72706   49.7685084  16.7543038

Incidentally, the closest approach of Apophis occurs during a New Moon. The Sun's longitude is ~24.24°, the Moon's longitude ranges from 22.80° to 25.77° over that time interval, and is ~24.28° at 21:45 UTC.
Here's a plot of the ecliptic longitude & latitude of Apophis. Please note that the vertical & horizontal scales are not equal! My lon-lat plotting script is here.

Here's a crude estimate of its magnitude. The magnitude script is here. Those bumps after 22:45 are probably algorithm artifacts due to rounding to the nearest whole number magnitude and then interpolating. Please see the Horizons manual for details.

Here are a couple of speed plots, created using my script in this space.SE answer.



Finally, here are a couple of screenshots from 3D orbit plots, covering the timespan between the last close approach and the next one, 2021-Mar-6 to 2029-Apr-13. The inclination of the Apophis orbit is only ~3.34° (relative to the ecliptic, which is smaller than the Moon's mean inclination (~5.14°). But the 3D views still contain useful information.
In the first plot, which uses a 50 day timestep, Apophis is the same reddish shade that I've used in the above graphs, the Earth is blue, and the Sun is orange. The horizontal grey line from the Sun is the equinox direction. It appears that Apophis makes two close approaches to Earth's orbit, but the crossover in the upper part of the image occurs well below the ecliptic plane.

The following plot, which uses a 5 day timestep, shows the motion of Apophis relative to Earth. Apophis is coloured using a rainbow sequence. Earth is a pale bluish grey.

The 3D plotting script is linked in the same answer as my magnitude plotting script.

> **Comments:**
> **username_0**: "This isn't a complete answer..." I suggest the following, perhaps as a new answer to separate useful information from the cool-looking information: Choose a half-dozen locations on Earth's surface (Horizons allows lat/lon locations - you can even choose named locations like "Mars Florida" which always tricked me). For each location, plot altitude, azimuth and apparent magnitude for say a 12 hour window around 2029-Apr-13 21:45 UTC. Make the lines dashed during daylight or twilight and solid at night. Now THAT would be an actual partial answer to the question as asked; useful to sky watchers.  

---

