Events
IPAC organizes and hosts a number of meetings and conferences.
IPAC hosts seminars every Wednesday from 12-1pm in IPAC's Large Conference Room (102) except where noted. Directions can be found on the visitor information page. Pizza and soda are available for purchase at a modest fee. Some weeks, the Time Domain Forum talk (which is not a lunch talk) is held on Thursday afternoons at 2:30 pm.
To receive seminar notification emails, you may sign up here. If you are interested in presenting a talk or seminar, please contact Peter Capak (Extragalactic), or Stephen Kane (Galactic/Solar System/Exoplanets). To present at the Time Domain Forum, contact Luisa Rebull.
Here is a partial list of astronomy-related talks in Pasadena:
- Caltech Astronomy Tea Talk (Mondays, 4pm)
- Caltech DPS Division Seminar (Mondays, 4pm)
- IR/sub-mm/mm Sack lunch series (Tuesdays, 12:15pm)
- Carnegie Colloquia series (Tuesdays, 4pm)
- Caltech Astronomy Colloquia (Wednesdays, 4pm)
- Caltech Physics Research Conference (Thursdays, 4pm)
- Carnegie Lunch Talk Series (Fridays, 12:15pm)
Special Note: For more astronomy related talks around Pasadena, check the following list maintained by IPAC scientist Solange Ramirez.
Wednesday, July 11, 2012
Since Johannes Kepler's predictions of transits of Mercury and Venus in 1631, and observations by Jeremiah Horrocks and William Crabtree of the 1639 transit of Venus, only 5 other transits of Venus have been observed: in 1761 and 1769, 1874 and 1882, and 2004. Expeditions were sent all over the world for the 18th and 19th century transits to follow the methods of Halley and others to determine the Astronomical Unit, giving the size and scale of the solar system, arguably the most important problem in astronomy for centuries. I will discuss how the infamous black-drop effect bedeviled astronomers in that quest for an accurate A.U., and how Glenn Schneider and I explained the effect through satellite observations of transits of Mercury, showing that it was not simply caused by the Cytherean atmosphere. During the 2004 transit, we worked with Richard Willson of ACRIMsat to detect the 0.1% drop in the Total Solar Irradiance, showing the effect of solar limb darkening, positioning such observations of transits of Venus and of Mercury as analogs to exoplanet transits. Our observations of the atmosphere of Venus with NASA's Transition Region and Coronal Explorer in 2004 led us to plan extensive observations of Venus's atmosphere and other phenomena during the June 5, 2012, transit of Venus, the last to be visible from Earth until 2117. We used NASA's Solar Dynamics Observatory, Hinode, ACRIMsat, and other spacecraft, and ground-based solar telescopes at Sacramento Peak, Kitt Peak, Big Bear, and Haleakala to observe the transit, as well as participating in the Venus Twilight Experiment from our perch at 10,000 feet on Haleakala, with 9 matched coronagraphs distributed around the world. I will give preliminary reports on these observations during this talk. I will discuss the attempt of David Ehrenreich, et al., to observe the transit of Venus in reflected light off the Moon during the 2012 transit, and our hopes for future observations of transits as seen from Jupiter and Saturn.
