Solar Eclipse Research Articles

Reconsidering the Existence of a Trend in the Asian Tropopause Aerosol Layer (ATAL) From 1979 to 2017

AbstractAn enhanced aerosol layer, known as the Asian Tropopause Aerosol Layer (ATAL), has been observed within the seasonal Asian monsoon anticyclone (AMA) since the late 1990s. Given the apparently abrupt appearance of this layer based on observations, it has been speculated that it originates from increasing human made emissions in Asia. However, the ATAL confinement is a result of a dynamical feature and does not purely consist of human made components. We herein investigate the possible existence of an ATAL earlier than the late 1990s. We exploit earliest possible, high quality space‐based aerosol observations from Stratospheric Aerosol and Gas Experiment, or SAGE (1979–1981), SAGE III/ISS (2017, ongoing) and revisit SAGE II (1984–2005) data analysis. We find that seasonal averaged solar occultation aerosol measurements (past and present) can neither be used to exclude the existence of the ATAL, nor to infer a significant trend. However, first CAM5‐MAM7 simulations indicate the presence of an ATAL signal for the tested years 1979 and 1980, with a human made component. We hypothesize that the human made component of the ATAL likely occurred since at least the 1970s, while the natural ATAL component (e.g., from dust) has always existed. Extended simulation based ATAL evolution studies are therefore the most reliable source for early ATAL investigations.

Satellite Visibility During the 2024 April Total Eclipse

On 2024 April 8, tens of millions of people across North America will be able to view a total solar eclipse. Such astronomical events have been important throughout history, but with nearly 10,000 satellites in orbit, we question whether total eclipses will now reveal a sky full of satellites, fundamentally changing this experience for humanity. Using the current population of Starlink satellites, we find that the brightest satellites would be naked-eye visible in dark skies, but the high sky brightness during totality will make them undetectable to the unaided eye. Our model does not take into account the effects of chance reflections from large, flat surfaces like solar panels, which we expect will cause glints and flares that could be visible from large satellites and abandoned rocket bodies. Time-lapse all-sky imaging might reveal satellites during the eclipse.

A Hypothesis on the Original Meaning of Samson’s Hair

The article presents the results of a study on the original meaning of Samson's hair, which according to the biblical text was the secret of his superhuman strength. In this narrative Delilah, after discovering that his power resides in his hair, cuts it, leaving him weakened and vulnerable, and then hands him over to the Philistines, who blind and imprison him. Drawing parallels between Delilah’s characteristics and those of ancient lunar goddesses like the Caucasian Dali, Diana and Artemis, connections are made between Delilah and the Moon. Likewise, earlier research, delving into the significance of Samson’s famous riddle, associates him with fire, metallurgical activities, and even the Sun itself (as indicated by the etymology of his name). This dual association—Delilah with the Moon and Samson with the Sun—is the key to understanding the original meaning of his hair, which is a sophisticated metaphor for the Sun’s corona, which shines at the climax of a total solar eclipse, when Earth, Moon and Sun align. This event casts a cold darkness over the Earth, with the Sun appearing weakened and “blinded”, resembling a black disk, surrounded by the corona, unable to provide light and warmth. Furthermore, additional hints, yet to be explored, suggest that other feats attributed to Samson may also symbolize celestial phenomena. It is also plausible that in ancient times the Sun's corona inspired the creation of regal diadems as well as radiate crowns—often adorned with seven rays, probably reminiscent of Samson’s seven braids—symbolizing the ruler's identification with the Sun itself. Keywords: Samson, Delilah, Dali, Diana, Artemis, Sun, Moon, Sun’s corona, solar eclipse, radiate crown

Variation in Total Electron Content Over Ethiopia During the Solar Eclipse Events

AbstractThis work studies variations of ionospheric total electron content (TEC) during four distinct solar eclipse events over the Ethiopia region. Dual‐frequency global positioning system (GPS) data obtained from UNAVCO over Addis Ababa (9.036°N, 38.76°E) and Bahir Dar (11.6°N, 37.34°E) stations are used to examine the ionospheric variability during two annular solar eclipses on 15 January 2010 and 1 September 2016, a partial solar eclipse on 4 January 2011, and a hybrid solar eclipse (the eclipse path starts out as annular but later changes to total) on 3 November 2013. The results show a significant decrease in TEC values during the occurrence of the solar eclipses. Specifically, the TEC values are reduced to −20% and −10% during the annular eclipse on 15 January 2010, −33% and −38% during the partial solar eclipse on 4 January 2011, −26% and −24% during the annular solar eclipse on 1 September 2016, over the Addis Ababa and Bahir Dar stations, respectively. There is only minimal change in TEC of −8% and −9% at Addis Ababa and Bahir stations, respectively, during the 3 November 2013 solar eclipse even if the obstruction rate is high over the study area. Furthermore, the study shows that the spatial gradient of TEC reduction varies at different locations, which is attributed to the distinct amount of reduction in solar radiation reaching the Earth's surface, resulting in reduced photo‐ionization. Overall, this study provides insightful information about the behavior of the ionospheric TEC during solar eclipses over Ethiopia and emphasizes the use of dual‐frequency GPS data in tracking the variations of the TEC.

The shape of the Sun

Abstract Are you in the path of the total solar eclipse on 8 April 2024? You are? Great! We need your help! And, er, don't forget to bring your smartphone…

Assuming Photon as Extended Point Particle in the HyperSoft Topological Space and other Hypotheses: Issues and Trend Analysis

Following our preceding article, where we discussed alternative interpretations of the advanced perihelion of Mercury, the present article revisits the 1919 solar eclipse expedition led by Arthur Eddington, which famously provided the first observational confirmation of Einstein's theory of general relativity. We focus on the deflection of starlight data obtained during the eclipse, a cornerstone of this validation. Here, we explore three alternative explanations for the observed light bending that challenge the sole attribution to general relativity. Firstly, the paper begins by arguing based on criticisms raised by Tullio Levi-Civita, a contemporary mathematician, regarding Einstein's use of pseudo-tensors in his calculations. Levi-Civita argued that this approach introduced unnecessary complexity and obscured alternative interpretations of the data. Secondly, we delve into astrophysical phenomena that could mimic the observed light deflection, based on the varying speed of light, by assuming a photon has mass. (cf. ‘t Hooft et al., Light is Heavy). Moreover, in the literature, Molodtsov initiated soft set theory as an extension of fuzzy set theory to deal with uncertainties occurring in the natural and social sciences. It attracted the attention of mathematicians as well as social scientists due to its potential to unify certain mathematical aspects and applications in decision making processes; therefore, we shall discuss a bit how to model the photon as an extended massive particle of light, possibly related to such a soft set point [15, 16]. For further exploration, it is possible to assume the crystalline lattice of subvacuum structure (cf. Gremaud) as part of hypersoft topological spaces [16, 16a]. We strongly believe that the true strength of science lies in its continuous search for evidence and refinement of existing models.  Therefore, it can be expected that new data can be helpful to reevaluate these matters, for instance, in the upcoming eclipse in the next month of 2024.

Study of Sky Radio Frequency Interference Background Level Behavior During the Partial Solar Eclips on 25 Oct. 2022 at The Baghdad University Location

Radiofrequency interference (RFI) describes the weakening of radio astronomy transmissions caused by man-made radio signal noise in radio telescope observation indicates the level of radio frequency noise in the sky at all times, regardless of any astronomical sources. This noise is affected by various sources, including Earth's atmosphere or solar activity and all communications equipment operating near the radio telescope. In this study, the background noise which includes RFI was measured using HSA2000 series receiver spectrum analyzer, which connected with two dipole antennas in different frequency bands (15-80 MHz) low band antenna, and (110-240 MHz) high band antenna during the partial solar eclipse in Baghdad on October 25, 2022, at (12:00-15:00), as a simple radio telescope to observe the radio astronomical background level in the sky. It is clear that the average amount of RFI level during a partial solar eclipse (-83.249 dBm for LBA decreased by about (0.93) from the value on a normal day (-77.495 dBm). And For HBA -84.711 dBm decreased by about (0.85) from the value on a normal day (-72.784 dBm). Also, it was noticed that these amounts are approximately equal to the RFI level at night (-82.352 dBm for LBA and -82.739 dBm for HBA). It is (0.98) for LBA and (0.97) for HBA, respectively. This research confirms that despite the short duration of the partial eclipse, the average value during the partial eclipse period is close to the average values during the night period due to the decrease in the electronic density of the ionosphere, especially at low frequencies, and the FRI of ground disturbances as a result of the activities of human from the surrounding the monitoring area.  also, found that at the monitoring point, there is a good relationship between the time of the maximum partial eclipse and the peaks of signal gain strength.

Education and observation of the 2023 hybrid solar eclipse in Southwest Papua

On April 20, 2023, the Southwest Papua region was the areas crossed by a hybrid solar eclipse. This outreach aims to enhance the community's understanding and awareness regarding the safety of solar eclipse observation by conducting observations at several locations in Southwest Papua. The Solar Gehana Education and Observation Program was successfully implemented in 6 Regencies/Cities in Southwest Papua. This activity was carried out using mini-lectures, pinhole training, and joint eclipse observations. In general, this program can increase public understanding and awareness regarding the safety of observing solar eclipses, with the training participants' response score being 79.92% in the good category. Apart from that, this program has succeeded in touching and opening people's insight into this fascinating natural phenomenon through widespread publication in the mass media, both regional and national.

Total Eclipse of the Sun

Things are looking up as millions of North Americans prepare to be dazzled by a celestial spectacle.

The Small Self and the Vast Universe: Eclipses and the Science of Awe

What is awe? What does it feel like? Why does it exist? And what is it about a total solar eclipse that seems perfectly designed to provoke it?

The End of the Eclipse

Scientists are studying how the Earth–Moon distance has changed over time, and what effect that change might have had on our planet. Future changes will extinguish total solar eclipses entirely.

Eclipse Science Along the Path of Totality

When a total solar eclipse sweeps across the United States on 8 April, scientists and enthusiasts alike will be there to document it.

Fatal Traffic Risks With a Total Solar Eclipse in the US

This case-control study describes the incidence of fatal traffic crashes in the US during the 2017 total solar eclipse.

Low-Level Clouds Disappear During a Solar Eclipse

Cumulus clouds rapidly dissipate as the land surface cools, a finding that has implications for Sun-obscuring geoengineering efforts.

Finding Partners Through Connections: Supporting Uvalde County with Solar Eclipse Resources

Finding Partners Through Connections: Supporting Uvalde County with Solar Eclipse Resources

Meteorological Data and Spectral Analyses of Non-Equilibrium Processes in Water during the Total Solar Eclipse of 11.08.1999 in Bulgaria

There are partial or total solar eclipses every year on our planet. They are observed from relatively small areas. From 1950 to 2100, three total solar eclipses fell within the territory of Bulgaria. The two solar eclipses from the 20th century were observed on 15.02.1961 and 11.08.1999. The next total solar eclipse will happen on 3.09.2081. The partial solar eclipses in Bulgaria were on 3.10.2005, 29.03.2006, 1.09.2008, 4.01.2011, and 25.10.2022. The question of the influence of solar eclipses on the Earth’s atmosphere, water, and living organisms is an area of interest for many researchers. In this connection, studies have been conducted on atmospheric and water parameters during partial and total solar eclipses. Most investigations were performed with meteorological data – temperature and humidity. In the last 30 years, other methods have also been applied for the investigations of solar eclipses – spectral methods with infrared (IR) spectroscopy, studies of magnetic and electric fields, polarization, and measurements of the parameters of the fluids in plants. Our studies have used meteorological methods and analyses. For the effects on the water, spectral methods are applied to the non-equilibrium energy spectrum (NES) and differential non-equilibrium spectrum (DNES). A deionized water sample examined during the solar eclipse on 11.08.1999 was used, aiming to analyze the parameters of NES and DNES. The deionized water control sample was tested on 10.08.1999 at the same time as the solar eclipse of the next day. The results of our research show relatively rapid and significant changes in air parameters during a solar eclipse, which are most prominent immediately after its culmination. The conditions of non-equilibrium arising during the solar eclipse allow for studying the restructuring of the hydrogen bonds of water molecules. The results of the current studies prove that the solar eclipse’s significantly affect water which is the primary substance in the Nature and living organisms. These data are consistent with other ones which also prove that, during a solar eclipse, the structure of water undergoes significant changes. By influencing the water, this natural phenomenon affects the whole Nature and all living organisms on the planet.

Forecasting Ionospheric TEC Changes Associated with the December 2019 and June 2020 Solar Eclipses: A Comparative Analysis of OKSM, FFNN, and DeepAR Models

This paper presents forecast and investigation of the variation in ionospheric Total Electron Content (TEC) during the solar eclipses (SEs) of December 2019 and June 2020 using three different methods: Deep Autoregressive model (DeepAR), Feed-Forward Neural Network (FFNN), and Ordinary Kriging-based Surrogate Model (OKSM), and the TEC data predicted by DeepAR, FFNN, and OKSM were compared with the actual TEC during the observation days. The study was conducted based on GPS data taken from the IISC receiver located in Bangalore, India, during the SEs which happened on 26.12.2019 and 21.06.2020. The TEC data were examined to assess the effect of solar eclipses on TEC values. Eighty-day prior TEC data for the IISC station are gathered from IONOLAB servers along with the other parameter data like Dst, Ap, F10.7, and Kp taken from OMNIWEB servers which were used to predict TEC. The reliability of the forecasted results is evaluated using numerical factors like Normalized Root Mean Square Error (NRMSE), Correlation Coefficient (CC), Root Mean Square Error (RMSE), Mean Absolute Error (MAE), and R-squared. The study demonstrates the usefulness of combining multiple methods for analyzing TEC variations during SEs and highlights the potential of OKSM, FFNN, and DeepAR models for studying TEC variation in the same context. The findings may be useful for satellite broadcasting and navigational services and for further research into the influence of solar eclipses on the TEC changes.

Engaging STEM Learners of All Ages: A University, Community, and K–12 Solar Eclipse Outreach Partnership

Engaging STEM Learners of All Ages: A University, Community, and K–12 Solar Eclipse Outreach Partnership

Distribution of atmospheric aerosols during the 2007 Mars dust storm (MY 28): Solar infrared occultation observations by SPICAM

Solar occultation measurements by the SPICAM IR on Mars-Express have been used to study aerosol vertical distribution during the 2007 global dust storm (GDS) of Mars Year 28. Measurements in the near-IR spectral range from 1 to 1.7 μm provide information about aerosol optical properties, extinction coefficient, particle size and number density. The observations were performed at Ls = 254–302° of MY28 and latitudes from 65°S to 65°N. Within the SPICAM spectral range we could not distinguish between absorption due to dust or water ice. The particle size distribution and its parameters, the effective radius reff and variance νeff, are retrieved assuming either mineral dust or water ice refraction indices. Before the MY 28 GDS at Ls < 265° the aerosol was detected from 20 to 60 km with dust particle size ∼0.75 μm below 50 km and decreasing with altitude above. The detached layers, presumably consisting of water ice, were observed at ∼60 km in the Southern hemisphere and 45 km in the Northern and Southern hemispheres with opacity <0.02 and 0.01–0.15, respectively. The effective radius varied from 0.2 to 1.6 μm with number density from 0.4 to 50 cm−3. With the development of the GDS dust reached to 80 km and higher, while reff tended to increase with altitude up to 0.9–1 μm at 70–75 km. The dust number density decreased from 2 to 4 cm−3 at 40 km to 0.1 cm−3 at 70–80 km. The dependence of the effective variance on altitude and season has been studied. Before the beginning GDS νeff varied below 50–60 km from 0.2 to 0.4 in the Southern hemisphere to 0.4–0.6 in the Northern hemisphere. During the GDS, the wider distribution propagated higher, with νeff ∼ 0.5 up to 70 km in the southern hemisphere. In high latitudes of both hemispheres at Ls = 268–275° optically thin water ice high altitude clouds were detected at 80–90 km with reff < 0.5 μm and number density 10–100 cm−3.

The Climatology of Mars Thermospheric Polar Warming at Aphelion

AbstractThermospheric polar warming (TPW) is observed conclusively for the first time at Mars during the aphelion/Northern Summer season using solar occultation (SO) measurements made by the Extreme Ultraviolet Monitor (EUVM) onboard the Mars Atmosphere and Volatile EvolutioN (MAVEN) orbiter. Aphelion data from Mars Year (MY) 33–36 are analyzed revealing TPW to be present at dawn but not dusk. This is consistent with an earlier analysis of accelerometer data from the Mars Global Surveyor that showed aphelion TPW is also not evident at 15 hr local time. Separating the data into individual MYs reveals TPW is observed during each year except MY 35. TPW is markedly intensified during MY 34, which is attributed to enhanced circulation caused by a northern‐hemisphere dust storm coinciding with the observations. Simulations from the Mars Climate Database predict the large TPW enhancement in MY 34 relative to MY 33 observed by EUVM SO, but predicts approximately 20K less overall TPW for both years than that observed by EUVM SO.