Luminosity of Sun in future from luminosity in present
======================================================

The luminosity of the Sun in the future can be calculated from the luminosity of the Sun in the present.

**Notes:**

#. The :ref:`formula for luminosity in the past <Luminosity of Sun in past from luminosity in present>`
   is not applicable here due to non-linearity.

**Conditions:**

#. The formula is valid while the Sun is `on the main sequence <https://faculty.wcas.northwestern.edu/infocom/The%20Website/end.html>`__.

..
    TODO find link

.. py:currentmodule:: symplyphysics.laws.astronomy.luminosity_of_sun_in_future_from_luminosity_in_present

.. py:data:: future_luminosity

    :attr:`~symplyphysics.symbols.astronomy.luminosity` of the Sun at some point in the future.

Symbol:
    :code:`L_1`

Latex:
    :math:`L_{1}`

Dimension:
    :code:`power`


.. py:data:: present_luminosity

    :attr:`~symplyphysics.symbols.astronomy.luminosity` of the Sun in the present.

Symbol:
    :code:`L`

Latex:
    :math:`L`

Dimension:
    :code:`power`


.. py:data:: time

    :attr:`~symplyphysics.symbols.basic.time` between now and the future event.

Symbol:
    :code:`t`

Latex:
    :math:`t`

Dimension:
    :code:`time`


.. py:data:: one_billion_years

    A quantity equal to one billion years.

Symbol:
    :code:`1 Gyr`

Latex:
    :math:`1 \, \text{Gyr}`

Dimension:
    :code:`time`


.. py:data:: law

    :code:`L_1 = L * (5.59 / (t / 1 Gyr) - 1.41 + 0.26 * t / 1 Gyr)`


    Latex:
        .. math::
            L_{1} = L \left(\frac{5.59}{\frac{t}{1 \, \text{Gyr}}} - 1.41 + 0.26 \frac{t}{1 \, \text{Gyr}}\right)