diff --git a/Project.toml b/Project.toml
index dde7d1ac566..0bafc1179bc 100644
--- a/Project.toml
+++ b/Project.toml
@@ -63,7 +63,7 @@ DocStringExtensions = "0.8, 0.9"
 FastGaussQuadrature = "0.4, 0.5, 1"
 HDF5_jll = "~1.12"
 ImageFiltering = "0.7"
-Insolation = "0.6"
+Insolation = "0.8"
 Interpolations = "0.14"
 IntervalSets = "0.5, 0.6, 0.7"
 Krylov = "0.9"
diff --git a/docs/Manifest.toml b/docs/Manifest.toml
index 32a57907b04..24fe35727b4 100644
--- a/docs/Manifest.toml
+++ b/docs/Manifest.toml
@@ -777,9 +777,9 @@ version = "1.4.0"
 
 [[deps.Insolation]]
 deps = ["Artifacts", "Dates", "DelimitedFiles", "Interpolations"]
-git-tree-sha1 = "36fe16ea725ed8c8eb5fd066fd8d0ef14adc80dd"
+git-tree-sha1 = "937658520f9d5786ea11b70713163fe277925492"
 uuid = "e98cc03f-d57e-4e3c-b70c-8d51efe9e0d8"
-version = "0.6.0"
+version = "0.8.0"
 
 [[deps.IntegerMathUtils]]
 git-tree-sha1 = "b8ffb903da9f7b8cf695a8bead8e01814aa24b30"
@@ -1270,9 +1270,9 @@ version = "2.2.8"
 
 [[deps.Primes]]
 deps = ["IntegerMathUtils"]
-git-tree-sha1 = "4c9f306e5d6603ae203c2000dd460d81a5251489"
+git-tree-sha1 = "1d05623b5952aed1307bf8b43bec8b8d1ef94b6e"
 uuid = "27ebfcd6-29c5-5fa9-bf4b-fb8fc14df3ae"
-version = "0.5.4"
+version = "0.5.5"
 
 [[deps.Printf]]
 deps = ["Unicode"]
diff --git a/examples/Manifest.toml b/examples/Manifest.toml
index 00ea63173e0..2b75d4d6050 100644
--- a/examples/Manifest.toml
+++ b/examples/Manifest.toml
@@ -172,9 +172,9 @@ weakdeps = ["SparseArrays"]
 uuid = "2a0f44e3-6c83-55bd-87e4-b1978d98bd5f"
 
 [[deps.BitFlags]]
-git-tree-sha1 = "43b1a4a8f797c1cddadf60499a8a077d4af2cd2d"
+git-tree-sha1 = "2dc09997850d68179b69dafb58ae806167a32b1b"
 uuid = "d1d4a3ce-64b1-5f1a-9ba4-7e7e69966f35"
-version = "0.1.7"
+version = "0.1.8"
 
 [[deps.BitTwiddlingConvenienceFunctions]]
 deps = ["Static"]
@@ -1086,9 +1086,9 @@ version = "1.4.0"
 
 [[deps.Insolation]]
 deps = ["Artifacts", "Dates", "DelimitedFiles", "Interpolations"]
-git-tree-sha1 = "36fe16ea725ed8c8eb5fd066fd8d0ef14adc80dd"
+git-tree-sha1 = "937658520f9d5786ea11b70713163fe277925492"
 uuid = "e98cc03f-d57e-4e3c-b70c-8d51efe9e0d8"
-version = "0.6.0"
+version = "0.8.0"
 
 [[deps.IntegerMathUtils]]
 git-tree-sha1 = "b8ffb903da9f7b8cf695a8bead8e01814aa24b30"
@@ -1929,9 +1929,9 @@ version = "2.2.8"
 
 [[deps.Primes]]
 deps = ["IntegerMathUtils"]
-git-tree-sha1 = "4c9f306e5d6603ae203c2000dd460d81a5251489"
+git-tree-sha1 = "1d05623b5952aed1307bf8b43bec8b8d1ef94b6e"
 uuid = "27ebfcd6-29c5-5fa9-bf4b-fb8fc14df3ae"
-version = "0.5.4"
+version = "0.5.5"
 
 [[deps.Printf]]
 deps = ["Unicode"]
@@ -2520,9 +2520,9 @@ version = "0.4.1"
 
 [[deps.Unitful]]
 deps = ["Dates", "LinearAlgebra", "Random"]
-git-tree-sha1 = "a72d22c7e13fe2de562feda8645aa134712a87ee"
+git-tree-sha1 = "242982d62ff0d1671e9029b52743062739255c7e"
 uuid = "1986cc42-f94f-5a68-af5c-568840ba703d"
-version = "1.17.0"
+version = "1.18.0"
 weakdeps = ["ConstructionBase", "InverseFunctions"]
 
     [deps.Unitful.extensions]
diff --git a/perf/Manifest.toml b/perf/Manifest.toml
index af0f302a8ff..6a54f0c83a5 100644
--- a/perf/Manifest.toml
+++ b/perf/Manifest.toml
@@ -178,9 +178,9 @@ uuid = "6e4b80f9-dd63-53aa-95a3-0cdb28fa8baf"
 version = "1.3.2"
 
 [[deps.BitFlags]]
-git-tree-sha1 = "43b1a4a8f797c1cddadf60499a8a077d4af2cd2d"
+git-tree-sha1 = "2dc09997850d68179b69dafb58ae806167a32b1b"
 uuid = "d1d4a3ce-64b1-5f1a-9ba4-7e7e69966f35"
-version = "0.1.7"
+version = "0.1.8"
 
 [[deps.BitTwiddlingConvenienceFunctions]]
 deps = ["Static"]
@@ -1133,9 +1133,9 @@ version = "1.4.0"
 
 [[deps.Insolation]]
 deps = ["Artifacts", "Dates", "DelimitedFiles", "Interpolations"]
-git-tree-sha1 = "36fe16ea725ed8c8eb5fd066fd8d0ef14adc80dd"
+git-tree-sha1 = "937658520f9d5786ea11b70713163fe277925492"
 uuid = "e98cc03f-d57e-4e3c-b70c-8d51efe9e0d8"
-version = "0.6.0"
+version = "0.8.0"
 
 [[deps.IntegerMathUtils]]
 git-tree-sha1 = "b8ffb903da9f7b8cf695a8bead8e01814aa24b30"
@@ -1261,9 +1261,9 @@ uuid = "9c1d0b0a-7046-5b2e-a33f-ea22f176ac7e"
 version = "0.2.1+0"
 
 [[deps.JuliaSyntax]]
-git-tree-sha1 = "d080fa670adde72509d03d91bf6ce6da2addb4be"
+git-tree-sha1 = "1a4857ab55396b2da745f07f76ce4e696207b740"
 uuid = "70703baa-626e-46a2-a12c-08ffd08c73b4"
-version = "0.4.6"
+version = "0.4.7"
 
 [[deps.KernelAbstractions]]
 deps = ["Adapt", "Atomix", "InteractiveUtils", "LinearAlgebra", "MacroTools", "PrecompileTools", "Requires", "SparseArrays", "StaticArrays", "UUIDs", "UnsafeAtomics", "UnsafeAtomicsLLVM"]
@@ -1987,9 +1987,9 @@ version = "2.2.8"
 
 [[deps.Primes]]
 deps = ["IntegerMathUtils"]
-git-tree-sha1 = "4c9f306e5d6603ae203c2000dd460d81a5251489"
+git-tree-sha1 = "1d05623b5952aed1307bf8b43bec8b8d1ef94b6e"
 uuid = "27ebfcd6-29c5-5fa9-bf4b-fb8fc14df3ae"
-version = "0.5.4"
+version = "0.5.5"
 
 [[deps.Printf]]
 deps = ["Unicode"]
@@ -2614,9 +2614,9 @@ version = "0.4.1"
 
 [[deps.Unitful]]
 deps = ["Dates", "LinearAlgebra", "Random"]
-git-tree-sha1 = "a72d22c7e13fe2de562feda8645aa134712a87ee"
+git-tree-sha1 = "242982d62ff0d1671e9029b52743062739255c7e"
 uuid = "1986cc42-f94f-5a68-af5c-568840ba703d"
-version = "1.17.0"
+version = "1.18.0"
 weakdeps = ["ConstructionBase", "InverseFunctions"]
 
     [deps.Unitful.extensions]
diff --git a/src/callbacks/callbacks.jl b/src/callbacks/callbacks.jl
index ac8eb185391..bde9e03d9f6 100644
--- a/src/callbacks/callbacks.jl
+++ b/src/callbacks/callbacks.jl
@@ -10,7 +10,7 @@ import SciMLBase
 import .Parameters as CAP
 import DiffEqCallbacks as DECB
 import ClimaCore: InputOutput
-import Dates
+using Dates
 using Insolation: instantaneous_zenith_angle
 import ClimaCore.Fields: ColumnField
 
@@ -47,7 +47,7 @@ NVTX.@annotate function rrtmgp_model_callback!(integrator)
     (; idealized_insolation, idealized_h2o, idealized_clouds) = p.radiation
     (; insolation_tuple, ᶠradiation_flux, radiation_model) = p.radiation
 
-    FT = eltype(params)
+    FT = eltype(parent(Y.c))
     thermo_params = CAP.thermodynamics_params(params)
     insolation_params = CAP.insolation_params(params)
 
@@ -102,8 +102,15 @@ NVTX.@annotate function rrtmgp_model_callback!(integrator)
         max_zenith_angle = FT(π) / 2 - eps(FT)
         irradiance = FT(CAP.tot_solar_irrad(params))
         au = FT(CAP.astro_unit(params))
-        (; orbital_data) = p.radiation
-
+        date0 = DateTime("2000-01-01T11:58:56.816")
+        d, δ, η_UTC =
+            Float64.(
+                Insolation.helper_instantaneous_zenith_angle(
+                    current_datetime,
+                    date0,
+                    insolation_params,
+                )
+            ) # TODO: This needs to be changed to FT
         bottom_coords = Fields.coordinate_field(Spaces.level(Y.c, 1))
         if eltype(bottom_coords) <: Geometry.LatLongZPoint
             solar_zenith_angle = RRTMGPI.array2field(
@@ -114,13 +121,12 @@ NVTX.@annotate function rrtmgp_model_callback!(integrator)
                 radiation_model.weighted_irradiance,
                 axes(bottom_coords),
             )
-            ref_insolation_params = tuple(insolation_params)
             @. insolation_tuple = instantaneous_zenith_angle(
-                current_datetime,
-                orbital_data,
+                d,
+                δ,
+                η_UTC,
                 bottom_coords.long,
                 bottom_coords.lat,
-                ref_insolation_params,
             ) # the tuple is (zenith angle, azimuthal angle, earth-sun distance)
             @. solar_zenith_angle =
                 min(first(insolation_tuple), max_zenith_angle)
@@ -128,13 +134,7 @@ NVTX.@annotate function rrtmgp_model_callback!(integrator)
                 irradiance * (au / last(insolation_tuple))^2
         else
             # assume that the latitude and longitude are both 0 for flat space
-            insolation_tuple = instantaneous_zenith_angle(
-                current_datetime,
-                orbital_data,
-                0.0,
-                0.0,
-                insolation_params,
-            )
+            insolation_tuple = instantaneous_zenith_angle(d, δ, η_UTC, 0.0, 0.0)
             radiation_model.solar_zenith_angle .=
                 min(first(insolation_tuple), max_zenith_angle)
             radiation_model.weighted_irradiance .=