exoplanets

Measuring an exoplanet transit

Objectives: 

After doing this activity you should be able to:

  • Use SalsaJ to do photometry for an exoplanet transit
  • Use a spreadsheet to create a light curve showing how the brightness of the target star changes over time 
  • Describe how the light curve shows that as the planet goes in front of the star it blocks some of the light
This activity, like Agent Exoplanet, allows you to use sample data to measure the change in brightness of a star as a planet passes in front of it. In this activity you will use SalsaJ, a free amateur photometry software program, to measure the brightness of the star by hand. You will then use a spreadsheet to plot your results as a graph and see if you can see your light curve.

The Possibilities And Search For Life Beyond Our Solar System

Detecting Atmospheres of Extrasolar Planets

Within our solar system quite a bit of exploration has been done by spacecraft including orbiters and landers. Planets outside our solar system will be difficult or impossible to explore with spacecraft in our lifetimes, so astronomers and astrobiologists use other techniques to search for signs of life on these planets. In particular, astronomers are interested in planets within the habitable zone of stars.

Tags: 
SETI
life
CoRoT
Kepler
exoplanets

Investigate transiting exoplanets with Agent Exoplanet

Our first totally online, citizen science project was launched today. It is called Agent Exoplanet and is about investigating transiting exoplanets. The 'Agent' part of the name is gives the project a secret agent theme. It might seem a little strange for an astronomy project but the key similarity is that astronomers are like detectives. Very often in science you have a small amount of information to go on to try to unlock the secrets of the Universe.

Long-Term Transit Timing Monitoring and Refined Light Curve Parameters of HAT-P-13b

We present 10 new transit light curves of the transiting hot Jupiter HAT-P-13b, obtained during two observational seasons by three different telescopes. When combined with 12 previously published light curves, we have a sample consisting of 22 transit light curves, spanning 1,041 days across four observational seasons. We use this sample to examine the recently observed large-amplitude transit timing variations (Pal et al. 2011), and give refined system parameters.

Fulton et al. 2011, accepted by AJ

WASP-41b: A Transiting Hot Jupiter Planet Orbiting a Magnetically Active G8V Star

We report the discovery of a transiting planet with an orbital period of 3.05 days orbiting the star TYC 7247-587-1. The star, WASP-41, is a moderately bright G8 V star (V = 11.6) with a metallicity close to solar ([Fe=H] = -0.08 +/- 0.09). The star shows evidence of moderate chromospheric activity, both from emission in the cores of the Ca II H and K ines and photometric variability with a period of 18.4 days and an amplitude of about 1%. We use a new method to show quantitatively that this periodic signal has a low false-alarm probability.

Published in PASP, 2011, 123, 547-554

WASP-39b: a highly inflated Saturn-mass planet orbiting a late G-type star

We present the discovery of WASP-39b, a highly inflated transiting Saturn-mass planet orbiting a late G-type dwarf star with a period of 4.055259 ± 0.000008 d, Transit Epoch T0 = 2455342.9688 ± 0.0002 (HJD), of duration 0.1168 ± 0.0008 d. A combined analysis of the WASP photometry, high-precision follow-up transit photometry, and radial velocities yield a planetary mass of Mpl = 0.28 ± 0.03 MJ and a radius of Rpl = 1.27 ± 0.04 RJ, resulting in a mean density of 0.14 ± 0.02 ρJ.

Accepted by A&A

WASP-35b, WASP-48b and WASP-51b: Two new planets and an independent discovery of HAT-P-30b

We report the detection of WASP-35b, a planet transiting a metal-poor ([Fe/H] = -0.15) star in the Southern hemisphere, WASP-48b, an inflated planet which may have spun-up its slightly evolved host star of 1.75 Rsun in the Northern hemisphere, and the independent discovery of HAT-P-30b / WASP-51b, a new planet in the Northern hemisphere.

submitted to AJ

Title: WASP-23b: a transiting hot Jupiter around a K dwarf and its Rossiter-McLaughlin effect

We report the discovery of a new transiting planet in the Southern Hemisphere. It has been found by the WASP-South transit survey and confirmed photometrically and spectroscopically by the 1.2m Swiss Euler telescope, LCOGT 2m Faulkes South Telescope, the 60 cm TRAPPIST telescope and the ESO 3.6m telescope. The orbital period of the planet is 2.94 days. We find it is a gas giant with a mass of 0.88 +/- 0.10 Mj and a radius estimated at 0.96 +/- 0.05 Rj .
Accepted for A&A

MOA-2009-BLG-387Lb: A massive planet orbiting an M dwarf

We report the discovery of a planet with a high planet-to-star mass ratio in the microlensing event MOA-2009-BLG-387, which exhibited pronounced deviations over a 12-day interval, one of the longest for any planetary event. The host is an M dwarf, with a mass in the range 0.07 M_sun < M_host < 0.49M_sun at 90% confidence. The planet-star mass ratio q = 0.0132 +- 0.003 has been measured extremely well, so at the best-estimated host mass, the planet mass is m_p = 2.6 Jupiter masses for the median host mass, M = 0.19 M_sun.

Accepted by A&A

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