New Mars Forums

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,383

Re: Optical Astronomy

Jupiter is well within the Mars-Tracker panel at TheSkyLive.com.

Mars is moving to the left above Jupiter and it will be standing above Jupiter later today.  The view provided by the display is (probably) similar to what one would see if in a spacecraft leaving Earth on a voyage to Mars. The background is derived from actual optical plates taken by observatories as digital files. Unlike with the view from a spacecraft however, the display includes handy labels for planets, galaxies and some of the brighter stars.

This report is posted at 11:49 UTC.

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tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,383

Re: Optical Astronomy

Mars is standing directly above Jupiter as seen from Earth, at 16:49 UTC.

Greenwich, UK 08/14/2024, 17:48:46 Europe/London
Object: Mars  [ ▸ Sky Map ]
RA 05h 02m 26.3s Dec +22° 23' 13.6" Appar J2000
Mag: 0.90 (Estimated: JPL)  Const: Taurus
Sun Dist: 216,014,933 km [25.4 km/s]
Earth Dist: 228,553,167 km [31.4 km/s]

Greenwich, UK 08/14/2024, 17:50:46 Europe/London
Object: Jupiter  [ ▸ Sky Map ]
RA 05h 02m 26.6s Dec +22° 04' 44.4" Appar J2000
Mag: -2.17 (Estimated: JPL)  Const: Taurus
Sun Dist: 753,912,712 km [13.5 km/s]
Earth Dist: 803,497,880 km [34.6 km/s]

The Right Ascensions were the same a few moments ago.

The two planets are both visible in each-other's Tracker panels at TheSkyLive.com.

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GW Johnson

Member

From: McGregor, Texas USA

Registered: 2011-12-04

Posts: 5,797

Website

Re: Optical Astronomy

Here's an astronomical funny for y'all.  How much implied fun depends upon where you put the hyphen and who you are with.  Consider:  (1) naked-eye astronomy,  or (2) naked eye-astronomy. 

GW

---

GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,383

Re: Optical Astronomy

Jupiter is no longer visible in the Mars Tracker panel at TheSkyLive.com.

Mars is no longer visible in the Jupiter Tracker panel at TheSkyLive.com

It might be a while before humans get to see that lineup again.

Mars was almost exactly in the line of sight between Earth and Jupiter.

Jupiter has an orbital period of 11.86 years, according to Las Cumbres Observatory

Mars has an orbital period of 1.88 years, and Earth (of course) has an orbital period of 1 year.

I asked Gemini if it could predict the next equivalent alignment, and it clarified that such a prediction is not straight forward.

Here is a snapshot of the challenges it identified:

Predicting the Next Planetary Alignment: A Complex Challenge

Unfortunately, accurately predicting the exact date of the next alignment of Earth, Mars, and Jupiter is not straightforward.
Why is it so difficult?

    Orbital Eccentricity: The orbits of planets are not perfect circles but ellipses. This means the distance between planets varies throughout their orbits.
    Orbital Inclination: The planes of the planets' orbits are slightly tilted relative to each other.
    Gravitational Interactions: The gravitational pull of other celestial bodies, especially the Sun and the Moon, can perturb the orbits of planets.
    Definition of "Alignment": There are different ways to define alignment (e.g., exactly in a line, within a certain degree of arc).

Potential Approaches

While we can't provide a precise date, we can explore some potential approaches:

    Simplified Model: Assuming circular orbits and no perturbations, we could calculate the least common multiple of the orbital periods to find a theoretical alignment cycle. However, this would be a very rough estimate.
    Orbital Mechanics Software: Specialized software can model the orbits of celestial bodies with greater accuracy and can be used to simulate future positions.
    Observational Data: Analyzing historical alignment data can provide insights into patterns and potential future occurrences.

Further Considerations

    Type of Alignment: Are you interested in a perfect linear alignment, or would a close approximation suffice?
    Timeframe: Are you looking for the next alignment within a specific time period?

If you have access to astronomical software or data, providing more specific information about the desired alignment criteria could help refine the prediction.

I asked Gemini to calculate the difference in Declination. It found a difference of .31 degrees.

# Define functions to convert degrees, minutes, and seconds to decimal degrees
def deg_to_dec(deg, minutes, seconds):
  """Converts degrees, minutes, and seconds to decimal degrees."""
  return deg + minutes / 60 + seconds / 3600

# Extract Declination data for Mars and Jupiter
mars_dec = deg_to_dec(22, 23, 13.6)
jupiter_dec = deg_to_dec(22, 4, 44.4)

# Calculate the difference in Declination
dec_difference = abs(mars_dec - jupiter_dec)

# Print the difference in arcseconds (round to 2 decimal places)
print(f"Difference in Declination: {dec_difference * 3600:.2f} arcseconds")

and then:

Result:

Difference in Declination: 1109.20 arcseconds

Therefore, based on your observations, Mars and Jupiter were separated by approximately 1109.20 arcseconds in Declination at the time of observation. Since 1 degree is equal to 3600 arcseconds, this difference is equivalent to about 0.31 degrees.

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tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,383

Re: Optical Astronomy

As a follow up to Post #29, I asked Gemini to try again, using a starting time after the current period. It developed a strategy that appears reasonable to me.

profile picture

Let's just note that the starting point for the calculation must be AFTER the planets are separated by more than 1200 arcseconds.  The software will have to find the ** next ** occasion when the the two planets are separated by 1200 arcseconds.
Understanding the Challenge

You're absolutely correct. To accurately predict the next alignment, we need to find a starting point where the planets are separated by more than 1200 arcseconds.

This introduces a layer of complexity to the problem:

    We need to iteratively check the planetary positions until the separation exceeds 1200 arcseconds.
    Once this point is found, we can start our calculations to predict the next alignment.

Refining Our Approach

    Iterative Search:
        Set a starting date and time (e.g., one month after the August 14, 2024, alignment).
        Calculate the angular separation between Mars and Jupiter.
        If the separation is less than 1200 arcseconds, increment the date and repeat.
        Once the separation exceeds 1200 arcseconds, use this point as the starting point for the alignment prediction.

    Alignment Prediction:
        Calculate angular speeds for Mars and Jupiter at this starting point.
        Determine relative angular speed.
        Estimate time to alignment based on the relative angular speed and the desired angular separation (1200 arcseconds).

Using JPL Horizons

To efficiently perform these calculations, we'll need to interface with a tool like JPL Horizons to retrieve planetary positions at different points in time. This will involve writing a script or program to automate the process.

Would you like to proceed with this refined approach? If so, I can provide more details on how to use JPL Horizons and potentially suggest programming languages or tools for the calculations.

Alternatively, if you have access to other astronomical software or datasets, we could explore using those as well.

I find that while I am interested in the question of when the next alignment will occur, I do not have the time needed to follow through.

If there is a member of the NewMars forum who would like to pursue the calculations, I'd be interested in the estimated time for the next alignment.

I note that the ability to predict planetary alignments is likely to be part of the tool set of a number of organizations who plan space missions.

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tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,383

Re: Optical Astronomy

The daily calendar update shows clearly that Mars is approaching Retrograde movement with respect to Earth.

Per Google, here is the schedule:

Search Labs | AI Overview
Learn more
…
Mars retrograde movement will begin on December 6, 2024 and last until February 23, 2025. During this time, Mars will appear to move in the opposite direction of the rest of the sky.
Explanation
Mars retrograde occurs when Mars appears to move backward in the sky, even though it's still moving forward in its own orbit. This happens because Earth is on an inner, faster track around the sun, so it passes Mars every 26 months. Before Earth pulls away around the bend in its orbit, Mars appears to change direction.
To see Mars during its retrograde period, look for it in the eastern sky after 10 PM. Mars is visible to the naked eye under clear, dark skies, and it has a reddish hue that distinguishes it from other planets and stars.

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