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A Bit More on Atmospheric Radio-Isotopes

as you said most of the C-14 is created in the Stratosphere and Mesosphere, i assume that is mostly because the density in the thermosphere and beyond is just so much less, and not related as much to the relative energies availableChatGPT

Your assumption is correct. The primary reason for the production of cosmogenic isotopes like carbon-14 (C-14) in the stratosphere and mesosphere, as opposed to higher altitudes in the thermosphere and beyond, is indeed related to atmospheric density.

In the thermosphere and exosphere (which includes the upper part of the thermosphere), the atmospheric density is extremely low. The number of particles available for interactions with cosmic rays is sparse compared to the denser regions of the atmosphere like the stratosphere and mesosphere. As a result, the likelihood of cosmic rays colliding with atmospheric particles and initiating nuclear reactions decreases with altitude.

In the denser layers of the atmosphere, particularly in the stratosphere and mesosphere, there are more nitrogen and oxygen molecules for cosmic rays to interact with, leading to the production of cosmogenic isotopes like C-14 and beryllium-10 (Be-10). These isotopes then have a greater chance of being transported downward through atmospheric processes, including mixing, precipitation, and other mechanisms, eventually reaching the Earth’s surface.

So, while the availability of atmospheric particles for interactions is a crucial factor, it’s also worth noting that the geomagnetic field and other factors play roles in modulating the penetration of cosmic rays into the atmosphere, influencing the altitude at which these nuclear reactions are most prominent.


Let’s review some of the SEP energies in the September 2017 Solar event which was massive.


location factors for cme from solar events are listed as S11W16 and S08W88 how does one relate those to the surface of the sunChatGPT

The coordinates S11W16 and S08W88 refer to specific locations on the solar surface, and they are typically given in a format known as the solar heliographic coordinates. These coordinates are used to specify the position of features on the Sun’s surface in a system tied to the Sun’s rotation.

Here’s how to interpret these coordinates:

  1. S11W16:
    • The “S” indicates a southern latitude (as opposed to “N” for northern latitude).
    • The number “11” represents the latitude, which means the region is located approximately 11 degrees south of the solar equator.
    • The “W” indicates a western longitude (as opposed to “E” for eastern longitude).
    • The number “16” represents the longitude, suggesting the region is around 16 degrees west of the central meridian on the solar surface.
  2. S08W88:
    • Similar to the first example, “S” indicates a southern latitude.
    • The number “08” represents the latitude, indicating approximately 8 degrees south of the solar equator.
    • The “W” indicates a western longitude.
    • The number “88” represents the longitude, suggesting the region is around 88 degrees west of the central meridian on the solar surface.

These coordinates provide a way to specify locations on the solar disk based on a coordinate system tied to the Sun’s rotation. The solar equator is designated as 0 degrees latitude, and the central meridian is 0 degrees longitude.

So, for example, if you imagine looking down on the Sun from above the solar system with the solar north pole at the top, S11W16 would be located about 11 degrees south of the solar equator and 16 degrees to the west of the central meridian.

These coordinates are often used in solar observations and studies to identify specific active regions, sunspots, or other features on the solar surface.


is the central meridian considered pointed right at earth and therefore moves as earth movesChatGPT

Yes, the concept of the central meridian on the Sun is indeed tied to the Earth’s perspective. The central meridian is an imaginary line on the solar surface that runs from the solar north pole to the solar south pole, and it is considered to be pointed directly at Earth.

As the Sun rotates on its axis, the central meridian moves across the solar disk. From the vantage point of Earth, it appears as if the central meridian is rotating, and the features on the solar surface, such as sunspots or active regions, can be observed at different longitudes.

The period of solar rotation is approximately 25 days at the solar equator and around 35 days at the solar poles. This rotation causes the central meridian to complete one full rotation approximately every 27 days when observed from Earth.

Scientists and astronomers use the central meridian as a reference point for solar observations. When specifying the position of solar features using solar heliographic coordinates (such as S11W16 or S08W88), the longitudes are measured from the central meridian. This system allows for a standardized way of describing features on the solar surface as they rotate across the Sun, giving a sense of the Sun’s rotation as observed from Earth.


and it is pointed directly at earth and not along a parker spiral with an assumed velocity


Yes, you’re correct. The central meridian of the Sun is considered to be pointed directly at Earth, and it is not aligned with the Parker spiral. The Parker spiral describes the spiral shape of the solar wind’s magnetic field as it extends outward from the Sun due to the Sun’s rotation.

While the solar wind and the solar rotation are related, the central meridian provides a reference point for solar features as observed from Earth. It is defined by the rotation of the Sun on its axis, and the features on the solar disk are measured in relation to this central meridian. This reference frame simplifies the description of solar observations and helps correlate features observed from Earth with their solar heliographic coordinates.

The Parker spiral is more relevant when considering the solar wind and its interaction with the interplanetary medium, whereas the central meridian is a concept used for describing solar features as seen from Earth.

How to define “where” something is on the Sun is done in 2 main ways, the Stonyhurst (Longitude is fixed for observers on earth, and thus considered the simplest) or the Carrington (yes that guy) recognizing that the suns rotation axis is slightly cocked compared to our orbit around it.


This is the Stonyhurst, in it a sunspot would appear on the northern hemisphere to Move up as it moves from left to right.

The tile above is exaggerated, P is just over 7 degrees, it shows here more like 30 degrees.

Here is an 1870 book on Heliographics, 150 years ago!


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