Luminosity Changes

With only seventy-four days until I leave for MDRS, the crew and I have been gradually learning about each other and figuring out what exactly we’ll be doing. Thankfully, because I’m a little anal and will be buried in work in a few weeks, I’ve been refining my own ideas over the past few days. It’s also necessary for a few sponsorships that some of my crewmates are trying to get, so having what we’ll actually be doing out in the desert written down helps us get money and plan everything out. I’ve also written a bio about myself for the crew website and the MDRS website, but that’s not up yet… So, let’s get on to the research!

Synopsis: A subset of three to seven Algol (EA/SD) variable stars will be observed using the Musk Observatory 0.36m telescope and CCD camera. The stars will be observed while watching for the two luminosity dips during one complete period, which will be measured and analyzed to extrapolate physical characteristics of the dimmer companion. Two exoplanet transits (HD 209458 and TYC 1987-1212-1) will also be observed in a similar fashion, but in the case of TYC 1987-1212-1 those observations will be to either confirm or deny the existence of the exoplanet. These projects will give a good indicator of what research can be completed on the planet Mars, and at MDRS, in future missions.

Description: Algol-type (EA/SD, eclipsing binary) stars are binary systems where the dimmer companion passes within the line of sight of the observer by moving in front of the brighter companion. This leads to a cyclic drop in luminosity twice during the entire orbit: once when the dim star is in front of the bright one and once when the dim star is behind the bright one. During the two times of occultation, the luminosity is for the most part constant once the dim companion is completely in front of or behind the brighter star, as viewed from our solar system.

The periodic luminosity changes of seven EA/SD Algol stars, with three (TX CMa, R CMa, and AK CMi) being the primary targets of the study, will be analyzed from the Musk Mars Desert Observatory (Musk) at the Mars Desert Research Station (MDRS) near Hanksville, Utah. By observing the luminosity changes and the duration of the minima, the size and orbital separation of the stars, thereby refining the observed measurements of the variable stars.

Similarly, the current search for exoplanets involves observing planetary transits, such as the current Kepler mission. The basic premise for observation is the same: observe the target star to watch for luminosity changes due to the transiting planet. Two such targets will be analyzed, the parent stars being HD 209458 and TYC 1987-1212-1. The first star is a known exoplanet, so the observations would center on refining the measurements already obtained. As for TYC 1987-1212-1, the transiting exoplanet has not been verified, so observing these transits would either confirm or deny the existence of that planet.

Both of these experiments rely upon careful calibration of the equipment, long observing sessions, and careful analysis of the data. Due to the non-linearity of the luminosity changes, these observational targets are tough to observe, especially with periods of inclement weather poor observational conditions, and other weather-related variables. Such conditions, however, would be frequent on Mars, so a successful data set would verify that such research could be performed on the surface, as well as other less fickle projects.

One response to “Luminosity Changes

  1. Pingback: Final Preparations « Inside a Calculator