Blue Dots

Download Blue Dots report

Vincent Coudé du Foresto — 2010-06-30T08:09:00Z

The latest version (currently 2.02) of the Blue Dots report is available here for download. This version has been approved by the Working Group coordinators. - News

Summary of the Pathways conference

Vincent Coudé du Foresto — 2009-12-21T14:15:00Z

At the initiative of Blue Dots and other sponsors, exoplanet scientists from around the world gathered in Barcelona on September 14th-18th, 2009, to debate and reach a consensus on defining guidelines for a new roadmap with the ultimate objective of finding habitable, and potentially inhabited, planets outside of our Solar System. In addition they reached an agreement on an appropriate framework for developing such an initiative. A full program with presentation downloads can be found here. A hardcover Proceedings book will be published during the summer 2010.

During the conference, researchers presented recent discoveries and debated on the roles of future space missions and ground-based facilities for finding habitable planets around nearby stars. They concluded that only an organized and structured international cooperation could allow the fulfillment of this goal in the following decades. Therefore this “Barcelona Process” marks the commencement of a new era in exoplanet research through:

The constitution of an interdisciplinary and international scientific community, organized and coherent with the objectives it seeks.
The creation of a Permanent Committee, which will coordinate and encourage the implementation of these objectives.
The organization of a conference every three years, possibly in Barcelona, which will allow the supervision and adjustment of the roadmap from results obtained through research as well as development and implementation of new technologies. In turn, these meetings should act as a laboratory of ideas capable of orienting the decisions that governments and space agencies could take in the mid and long run.

The process includes other recommendations such as the creation, in the near future, of an interdisciplinary center for meetings, the establishment of a fellowship program for young researchers and the advantages of defining an international public outreach program.

Roadmap milestones

During the Conference, four main steps were defined in order to fulfill the future objective of finding and characterizing habitable planets:

Carry out a statistical analysis of the frequency of exoplanets in our Galaxy, and especially those planets that are terrestrial in nature. This analysis includes elaborating a star survey; determining the stellar types that harbor planetary systems; exploring their structure, variety, and size distribution; and finding the frequency of terrestrial planets within the habitable zone. For this type of study, current technology is being employed, such as the space missions CoRoT and Kepler (transits) and the ground instrument HARPS (radial velocities). In the future, other space missions that study transits (PLATO, TESS) and gravitational lensing should be carried out to attain a global vision of the exoplanets in our Galaxy.
Carry out a space mission that could complete a survey of all the habitable exoplanets that fall within a radius of 50 light years from our Sun. These systems are close enough to be studied in detail. The astrometry technique has shown to be the most suitable method for this objective and, in particular, the SIM Lite mission (Space Interferometry Mission Lite), which is under study by NASA. This mission will be able to detect the reflex motion caused by Earth-size exoplanets by measuring the position of their host stars with high accuracy. To fulfill the objectives of this milestone, the role of complementary ground-based facilities such as HARPS and VLTI/PRIMA will be pivotal.
Carry out one or more missions (possibly through collaboration between space agencies) of transit observations in order to characterize hot terrestrial exoplanets. The James Webb Space Telescope (JWST, launch date in 2014), a joint mission between NASA and ESA, may be able to contribute to this objective. However a dedicated mission with an optimized design is needed to cover the wide spectral range needed, including the visible. Ground-based observations obtained with 10-m class telescopes (VLT) and the future giant 40-m class telescopes (E-ELT) could provide important contributions to the characterization of transits some of giant and Neptune-size exoplanets.
Launch a mission capable of characterizing habitable terrestrial exoplanets in search for biomarkers, as a joint collaboration between space agencies. To determine the technological approach of this flagship mission it is necessary to mature and assess concepts, including precursor missions, related to coronography, interferometry and external occulters. In addition, the experience gained from upcoming missions like SPICA (JAXA/ESA) and JWST (NASA/ESA) will be essential.

The Barcelona conference marked a starting point for new great expectations within the exoplanet scientific community. A symbolic step in the right direction was the announcement of the first terrestrial planet with both mass and radius measured, COROT-7 b, made during the conference. For the first time, we have been able to gather a multidisciplinary team of scientists, including biologists, geologists, astronomers, and planetary scientists, as well as representatives of the different space agencies and ground observatories, in order to agree upon a future vision and strategy. We will consolidate a European network of several hundred scientists which will allow us to work together to find and study planets that support life. Maybe, in the coming decades, we will able to address the question we have been seeking to answer for so long: Are we alone in the Universe?

Sagan Program and 2010 Sagan Fellowships

Vincent Coudé du Foresto — 2009-09-05T22:02:22Z

2010 SAGAN FELLOWSHIPS

The NASA Exoplanet Science Institute announces the 2010 Sagan Postdoctoral Fellowship Program and solicits applications for fellowships to begin in the fall of 2010.

The Sagan Fellowships support outstanding recent postdoctoral scientists to conduct independent research that is broadly related to the science goals of the NASA Exoplanet Exploration area. The primary goal of missions within this program is to discover and characterize planetary systems and Earth-like planets around nearby stars. The proposed research may be theoretical, observational, or instrumental. This program is open to applicants of any nationality who have earned (or will have earned) their doctoral degrees on or after January 1, 2007, in astronomy, physics, or related disciplines. The fellowships are tenable at U.S. host institutions of the fellows' choice, subject to a maximum of one new fellow per host institution per year. The duration of the fellowship is up to three years: an initial one-year appointment and two annual renewals contingent on satisfactory performance and availability of NASA funds.

The Announcement of Opportunity, which includes detailed program policies and application instructions is available at this web site:

Applicants must follow the instructions given in this Announcement. Applications must be submitted electronically through the above website. Inquiries about the Sagan Fellowships may be directed to saganfellowship§ipac.caltech.edu.

The deadline for both applications and letters of reference is Thursday, November 5, 2009. Offers will be made before February 1, 2010, and new appointments are expected to begin on or about September 1, 2010.

Key science questions

Vincent Coudé du Foresto — 2009-09-05T21:22:36Z

Sagan et al. (1993) analyzed a spectrum of the Earth taken by the Galileo probe, searching for signatures of life and concluded that the large amount of O2 and the simultaneous presence of CH4 traces are strongly suggestive of biology. To characterize a planet's atmosphere and its potential habitability, we look for absorption features in the emergent and transmission spectrum of the planet. The spectrum of the planet can contain signatures of atmospheric species, what creates its spectral fingerprint. On Earth, some atmospheric species exhibiting noticeable spectral features in the planet's spectrum result directly or indirectly from biological activity: the main ones are O2, O3, CH4, and N2O. CO2 and H2O are in addition important as greenhouse gases in a planet's atmosphere and potential sources for high O2 concentration from photosynthesis. The presence or absence of these spectral features (detected individually or collectively) will indicate similarities or differences with the atmospheres of terrestrial planets, and its astrobiological

The KEY questions:

Biosignatures
- What could constitute a (remotely detectable) biosignature under what conditions?
Conditions under which other biosignatures can form
- e.g. methane biosignature and the limits of methanogens.?
Minimum physical & chemical requirements to create a habitable environment
- Early environments impact on evolution of life
- Extreme physical & chemical limits for life in general
- Physical and chemical limits of photosynthesis
- Impact of total atmospheric pressure on microbes
- Man-made biosignatures & identification of advanced life
- SuperEarth environments and life
- Influence of stellar activity on an atmosphere
- Is there a min or maximum mass for habitability?
- Is there a minimum mass for plate tectonics on a planet?
- What geochemical cycles could globally dominate a planet?

Key science questions

Vincent Coudé du Foresto — 2009-09-05T21:13:32Z

The following have been identified as key science questions for the Formation and Evolution of Planetary Systems theme:

Circumstellar disk evolution and Planet formation
- How are the temporal evolution of circumstellar disks and the formation of planets connected? What is the role of planet-disk interactions on the planetary system formation process?
- Which roles do host mass and metallicity play?
- What is the role of the star/planet formation environment (low-mass vs. high-mass star forming regions, clusters)?
- Which are the conditions that decide about predominance the planet formation scenario: Core accretion vs. Gravitational instability?
- Are there fundamental differences in the planet formation in single vs. binary/multiple systems?
- What range of terrestrial planet compositions is produced through the processes of planet formation?

Evolution of planetary systems
- Are there common criteria for the long-term stability of planetary systems?
- What is the "typical" planetary architecture, and what range is realized in nature?
- How does planet migration affect the resulting planetary architectures?
- What is the correlation of the presence of telluric planets with existence of superearths and gas giants?
- Is there a correlation between the existence and location of planetesimal belts and the existence of planets?
- Do exo-Oort's clouds exist and what is their role in the planet formation/evolution process?
- What are the properties of potentially existing free-floating Earth-mass objects?
- Which are the major unique characteristica of the Solar System?

Habitable Zone
- Which parameters determine the region of the habitable zone in planetary systems? (Rem.: Is the term ``habitable zone'' a good working term at all?: a) There are many parameters that play a role to provide liquid water. b) There are many further parameters — beyond the existence of liquid water — that obviously played a major role to make Earth habitable.)
- Are giant outer planets a prerequisite for inner telluric planets with habitable zones?
- How does the stellar habitable zone evolve in time?
- Which are additional criteria which determine the habitability of planetary satellites?
- Is it possible to identify / separate a galactic habitable zone (bulge, disk, halo, clusters)?
- How might the formation history and subsequent dynamical evolution affect the potential for habitability? (e.g. outgasing, loss of atmosphere, internal energy and hence plate tectonics, impacts, orbital change, stability).

Key science questions

Vincent Coudé du Foresto — 2009-09-05T21:03:16Z

The following have been identified as key science questions for the Targets and their Environments theme:

What are the physical properties (including mass and age) of the target stars? This requires the determination of the fundamental stellar properties such as the mass, radius, chemical composition, and age. The possible techniques to obtain this information are the use of accurate calibrations of mass and radius, stellar evolution models and asteroseismology.
What are the radiative properties (light and particles, T_eff, L_bol of the target stars? The overall radiative properties are the effective temperature and the luminosity, although a detailed spectral energy distribution covering from high (X-rays) to low energies (IR, radio) is essential. Spectroscopy is required to characterize the the radiation field. Particle emissions in the form of stellar wind are also a requirement to fully describe the stellar radiation. Related to this, it is important to characterize the magnetic properties of the star (including flares and mass ejections) since they are basic to understand star-planet interactions.
What is the time-variation of such emissions ? The stellar emissions need to be characterized also in their time variation. This is especially relevant to the high-energy and particle components. The characterization must include all timescales, including those of minutes and hours (microvariability, flares), days (spot modulations), years (spot cycles), centuries (Maunder-like minima) and Gyr (rotational spin down). The targets themselves can be used to investigate the short timescales, but the long-term changes can only be determined using stellar ensembles or stellar proxies to reconstruct the overall history.
What are the characteristics of the stellar immediate surroundings (i.e., zodiacal dust, companion stars, brown dwarfs or giant planets)? The properties of the stellar surroundings include the zodiacal dust (parameterized as the surface brightness vs. wavelength) and the multiplicity. The latter comprises stellar and brown dwarf companions, but also the presence of Jupiter-size planets, which may influence the presence of telluric planets.
What are the stellar properties (mass, chemical composition) influencing the existence of telluric planets? This question boils down to determining eta_Earth(M,Z). That is, the fraction of stars with telluric planets as a function of stellar mass and chemical composition. This question is essential to decide what stellar types are the optimum targets for detailed searches. The correlation with parameters such as multiplicity and age must also be investigated. Additionally, putting our own Sun in context is highly relevant. Questions such as the comparison between the Sun and other solar-like stars or the existence of chemical abundance patterns may provide important clues on the process of planet formation. In the latter case, it is important to compare the abundances of biogenic elements (C,N,O,P,S) in the Sun to those measured in other solar like stars.
What is the census of telluric planets in the solar neighborhood? A survey of the solar neighborhood should be conducted to uncover the presence of telluric planets and especially those in the habitable zones of their parent stars.
What are the properties of stars and their circumstellar environments (disks, outflows) in which planets are actually forming? What are the earliest stages when this happens, and what environments are conducive to planet formation? A survey of disk-surrounded classical T Tauri stars and disk-less weak-lined T Tauri stars in the nearest star-forming regions should be conducted. The presence of planets may be evidenced by disk properties (gaps, etc), but radial velocity measurements may be more reliable.

Draft Blue Dots report

Vincent Coudé du Foresto — 2009-09-04T12:49:00Z

Here's the latest draft (version 1.3, July 26th, 2009) of the Blue Dots report. Do not hesitate to send your feedback to team.bluedots§obspm.fr .

The report will be finalized before the end of 2009, taking into account elements from the Pathways conference.

Blue Dots meeting #6

Vincent Coudé du Foresto — 2009-03-08T17:11:18Z

The next Blue Dots meeting will be hosted at ISSI in Bern on March 25th and 26th, in conjunction with the meeting of the ISSI team led by Helmut Lammer.

Participants:

Roy Alonso
Vincent Coudé du Foresto
Stefan Dieters (for Jean-Philippe Beaulieu)
Malcolm Fridlund
Lisa Kaltenegger
Maxim Khodachenko (Wednesday only)
Fabien Malbet
Marc Ollivier
Jean Schneider
Franck Selsis
Mike Shao
Daphne Stam (for Govianna Tinetti)
Stephane Udry (Thursday only)

Agenda:

Wednesday, March 25th

9h30 - 10h10: ESA news and EPRAT status (Fridlund+ discussion)
10h10 - 10h30: Report on CNES prospective forum (Ollivier + discussion)
10h30 - 11h00: Blue dots report, status and community feedback (Foresto & discussion)

- 11h00 - 11h30: coffee break

11h30 - 12h15: Reviewing the key science questions: Planetary atmospheres and surfaces (Stam & discussion)
12h15 - 13h00: Reviewing the key science questions: Habitability criteria (Kaltenegger & discussion)

- 13h00 - 14h30: lunch

14h30 - 16h00: Reviewing the critical questions (discussion, all)
15h15 - 16h00: Pathways conf. status, presentation of new Web site (Ribas + discussion)

- 16h00 - 16h30: coffee break

16h30 - 17h15: Preparing the future: Europlanet funding possibilities (Lammer), turning Blue Dots into an institutionalized european network (with support for PhDs, postdocs etc.) ?
17h15 - 18h00: Discussion on Pathways conf. (all): review invited speakers, satellite meetings, action items

- 20h00: dinner at Zunft zu Webern in the old town (Gerechtigkeitsgasse 68)

Thursday, March 26th

9h30 - 11h00: Detecting habitable planets by astrometry (Shao, 45mn + 45mn discussion): potential & planned missions

- 11h00 - 11h30: coffee break

11h30 - 13h00: Detecting habitable planets by radial velocity techniques (Udry, 45mn + 45mn discussion): potential & planned projects

- 13h00 - 14h30: lunch

14h30 - 15h00: Discussion: complementarity between the two techniques
15h00 - 15h30: Discussion: what remains to be clarified before drawing conclusions in the report ?
15h30 - 16h00: Preparing the next cycle: action items

ESA coordinator position open

Vincent Coudé du Foresto — 2009-02-03T11:59:38Z

A position at ESA has just opened for a Coordinator for Astronomy and Fundamental Physics Missions, who will play a major role in the implementation of the Cosmic Vision program. See here for details. Deadline for applications is Feb. 16th, 2009.

New article

Vincent Coudé du Foresto — 2008-12-13T18:47:25Z

This working group is supposed to formulate key questions about the formation and evolution of planetary systems (FEPS). Questions include circumstellar disk evolution and planetary formation (both in single binary star systems), planetary architecture evolution and stability, and ultimately the conditions and evolution of stellar habitable zones as well as planetary satellites.

Members are:

Willy Benz (Uni Bern, willy.benz§space.unibe.ch)
Willi Kley (Uni Tuebingen, wilhelm.kley§uni-tuebingen.de)
Sascha Krivov (FSU Jena, krivov§astro.uni-jena.de)
Michael Meyer (ETH Zürich, mmeyer§as.arizona.edu)
Sebastian Wolf (CAU Kiel, wolf@astrophysik.uni-kiel.de), co-chair
Hans Zinnecker (AIP Potsdam, hzinnecker@aip.de), chair

more members will be added in due course...