Giant Sunspots - August 12, 2024

BYU Astronomy Research Group Joins the Astrophysical Research Consortium (ARC)

As of January 2021 BYU will be a member of the ARC Consortium (Link to Consortium) with access to the ARC 3.5-m telescope and the 0.5-m ARCSAT telescope.  The primary use of the ARC 3.5-m telescope time is for graduate student projects.  This provides a wide array of instrumentation that is currently being used to study objects in the solar system all the way to studies of the large scale structure of the Universe.

Other BYU Astronomy Facilities

In addition to our telescope time from the ARC consortium, we operate a number of our own astronomical facilities

West Mountain Observatory (West Mountain)

This is our mountain observatory at about 6600 ft above sea level.  This consists of three telescopes: 0.9-m, 0.5-m, and a 0.32-m. It is a 40 minute drive that ends in a 5 miles drive up a dirt road. The mountain itself can be seen from campus. We don't provide any tours of this facility.

Orson Pratt Observatory

The Orson Pratt Observatory is named for an early apostle of the Church of Jesus Christ of Latter-Day Saints.  It is our campus telescope facility and contains a wide variety of telescopes for student research and public outreach. We operate a 24" PlaneWave telescope in the main campus dome, plus a 16", two 12", one 8", and a 6" telescope on our observation deck.  The telescopes are all fully robotic. Beyond this we have a large sections of telescopes used on public nights.

Royden G. Derrick Planetarium (Planetarium)

This is a 119 seat, 39" dome planetarium with acoustically treated walls to allow it's use as a lecture room. Recently we upgraded to an E&S Digistar7 operating system with 4K projectors.  The planetarium is used for teaching classes, public outreach, and astronomy education research projects.





Selected Publications

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Comparison of geomagnetic ap index with fluctuations in b and v - mariner 5
By D. E. Jones, J. R. Ballif, and J. G. Melville
Abstract:
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Physics: Fundamentals and Frontiers
Abstract:
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Cosmic-ray decreases and the occurrence of solar flares
By Jae R. Ballif, D. E. Jones, and D. T. Smith (et al.)
Abstract: Mechanisms proposed to account for observed relationships between the occurrence of solar flares and cosmic-ray decreases at the earth are examined by using a large fraction of all existing standardized flare data obtained from a continuously monitored sun. The interval studied extends from July 1957 through July 1968. A total of 76 cosmic-ray decreases were identified during this interval. By using epoch analysis as well as inspection of the original data, it was found that active flare-producing regions crossed central meridian just before the cosmic-ray decreases began. It was also found that a broad maximum in class 2 or greater flares occurred just before the decreases occurred. However, the flares forming this maximum were observed on the eastern part of the solar disk. Epoch analysis of decreases with greater amplitude show the same relationships to the occurrence of flares. Even the most intense decreases that were thought to be the result of specific known flares show a direct relationship to the time of central-meridian passage of active flare-producing regions. We conclude that our hypothesis that all large transient cosmic-ray decreases can be accounted for by interplanetary structure associated with active flare-producing regions is consistent with the data. Further, we find that, if such flare-producing regions are the site of class 2 or greater flares as they approach central meridian, the likelihood of a decrease at the earth is slightly increased.
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Morphology of a solar-terrestrial event in March 1966
Abstract: The authors assumed the existence of a long-lived stream structure in the interplanetary magnetic field during late March 1966. The main feature of this stream was a uniform, high-field core that passed the earth on March 24. The geomagnetic activity, anisotropy of solar particles over the energy range 0.6 to ∼100 Mev/nucleon, and the anisotropy of the Forbush decrease, which were observed during the event, were analyzed and were all found to be compatible with the proposed stream structure.
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Flares, Forbush decreases, and geomagnetic storms
Abstract: The authors hypothesize that individual flares are not the cause of either Forbush decreases or geomagnetic storms. Evidence supporting this hypothesis is here presented showing that geomagnetic storms and Forbush decreases can be accounted for entirely by the effects of interplanetary ‘streams.’ Major cosmic-ray variations begin near the time that a flare-producing region on the sun passes central meridian. This relationship and a similar relationship between geomagnetic storms and flare-producing regions is shown to exist even during the intervals that include the energetic flares that have produced ground-level increases in neutron monitor counts. Streams, closely associated with these flare-producing regions, are usefully described by the structure in the interplanetary magnetic field since fluctuations in the interplanetary field are highly correlated with the Kp index and the interplanetary field strength is inversely correlated with the cosmic-ray intensity. Such stream structure is used to account for the observed ‘center limb effect.’ It is also shown that when flares of importance 3— or greater occur within a few days of very high geomagnetic activity and at longitudes greater than 25° west, the major geomagnetic activity precedes the flare. This result is not easily explained by the hypothesis that periods of intense geomagnetic activity are due to individual flare effects.
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Further evidence on the correlation between transverse fluctuations in the interplanetary magnetic field and Kp
By Jae R. Ballif and D. E. Jones (et al.)
Abstract: The correlations between the Kp index and solar wind variables measured during the flights of Mariners 2, 4, and 5 are discussed. It is shown that during the time of these flights, Kp is highly correlated with σBT, N, a measure of the interplanetary magnetic field fluctuations. It is better correlated with this quantity than it is with either the interplanetary magnetic field strength or the plasma speed. Kp is given by the relation The typical, large-scale structure of events in the solar wind that occur in conjunction with major geomagnetic activity is also discussed.