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star planet Can Kepler see planets like Earth? New Words Kepler telescope space planets Earth Kepler (Kep-ler)is a telescope (tel-e-scope), Kepler looks into space, Kepler looks for planets (plan-ets). moon [...]

Byline: C. Burigana (1), P. Natoli (2), N. Vittorio (2), N. Mandolesi (1), M. Bersanelli (3) Keywords: cosmic microwave background; space vehicles; telescopes; data analysis; Solar System; general Abstract: In-flight measurements of the shape of the antenna main beam is a crucial input to the data analysis pipeline of each high resolution CosmicMicrowave Background (CMB) anisotropy experiment. We study the main beamreconstruction achievable by the PLANCK Low FrequencyInstrument (LFI) through the observation of external planets. Although werestrict our analysis to the 30 GHz LFI channel, the method can be easilyextended to all the PLANCK frequency channels and to other CMBanisotropy experiments. We show that it is possible to fit the timeordered data from the external planets (mainly Jupiter and Saturn) to obtain anaccurate, robust, simple and fast reconstruction of the main beamproperties under very general conditions, almost independently of the calibrationaccuracy. In addition, we find that a bivariate Gaussian approximation ofmain beam shapes represents a significant improvement with respect to asymmetric representation. The impact of the most relevant systematic effects is also addressed.We demonstrate that by combining the recoveryof the maximum signal at the planet transit with accurate in-flightcalibration, it is possible to measure the intrinsic planet temperaturesat millimetric wavelengths with &lt 1% accuracy. This work is based onPLANCK-LFI activities. Author Affiliation: (1) IASF, Sezione di Bologna, CNR, via P. Gobetti 101, I-40129, Bologna, Italy (2) Dipartimento di Fisica, Universita di Roma ``Tor Vergata'', via della Ricerca Scientifica 1, I-00133, Roma, Italy (3) Dipartimento di Fisica, Universita di Milano, and IASF, Sezione di Milano, CNR, via Celoria 16, I-20133, Milano, Italy Article History: Registration Date: 12/10/2004

Byline: Hector O. Castaneda (1,2,3), Ulrich Klaas (1,2) Keywords: photoconductive detectors; space vehicles; space weather Abstract: The effects of changes in the space environment on the ISOPHOT photoconductivedetectors over the whole ISO mission were studied using the complete setof responsivity check measurements taken after the curing of the detectors.We found that the responsivity of the Ge-based, low bias voltage far-infrared detectors (P3, C100, and C200) is sensitive to the conditions of the Space Weather.We present evidence that an increased responsivity level (20% -- 50%) after curing of the detectors is linked to the onset of geomagnetic storms. TheSi-based, high bias voltage detectors P1, P2 and PHT--SS show only small changesin their responsivity. An exception is the PHT--SL array which shows a similar,but less pronounced behaviour as the FIR detectors. While these relationshave been demonstrated by our study, a detailed physical understanding is still outstanding. The Space Weather dependent scatter of the responsivity,being the photometric scaling factor (conversion from measured photo currentto inband power on the detector), justifies the observing mode design to include frequent monitoring of its actual level. Author Affiliation: (1) Max-Planck-Institut fur Astronomie, Konigstuhl 17, D-69117, Heidelberg, Germany (2) Astrophysics Division, Space Science Department of ESA, ISO Science Operations Centre, Villafranca del Castillo, P.O. Box 50727, E-28080, Madrid, Spain (3) Instituto de Astrofisica de Canarias, E-38200, La Laguna, Spain Article History: Registration Date: 07/10/2004

Byline: E. Hog (1), C. Fabricius (1), V. V. Makarov (1) Keywords: astrometry; instrumentation: interferometry; photometry; space vehicles; telescopes Abstract: An interferometric astrometric mission, aiming at accuracies at around the10 microarcsec level, was recommended as a high priority concept within thenew ESA Horizon 2000+ scientific programme. The original outline concept forsuch a mission, GAIA, presented its general feasibility but did not addressmany questions of implementation or optimisation. Another concept of aninterferometer for a scanning astrometric satellite is presented. It containsa simpler optical telescope and a more efficient detector system. The designutilizes the full resolution of all light in the dispersed fringes of aFizeau interferometer. A preliminary optimization of the satellite indicatesthat two telescope units with a baseline of 100 cm will achieve a precisionof 3, 8, 22, 68, 302 microarcsec for parallaxes of stars with V = 12, 14, 16, 18, 20 mag, respectively, from a 5 year mission. Simultaneousspectrophotometry of the entire spectrum of each star will be obtained with aresolution corresponding to intermediate band photometry. The expectedprecision of this photometry is about 0.003 mag for V = 16. The performance is good in crowded fields, at least up to one star per 5 arcsec2. A Hipparcos-type beam combiner of 150 cm width is placed in front of atelescope with 4 square apertures of 50 cm. The assumed focal length is f = 60 m and the field 0.5 degree diameter. The detector consists of CCDs used for time delayed integration (drift-scan.) Author Affiliation: (1) Copenhagen University Observatory, Juliane Maries Vej 30, DK-2100, Copenhagen, Denmark Article History: Registration Date: 18/09/2004

The probability that giant-planet-like signals detected by the Kepler spacecraft are not from planets is higher than expected. The result underscores the importance of making follow-up observations to confirm the [...]

Rosetta mission would have to sacrifice other science to search for comet lander., Author(s): Elizabeth Gibney Author Affiliations: The Philae lander arrived on comet 67P on 12 November, but scientists lost contact with it just days later. ESA/Rosetta/MPS Scientists at the European Space [...]

Japan's Akatsuki probe is circling Venus on an even-closer orbit than mission managers had hoped for, the Japan Aerospace Exploration Agency announced on 9 December. In 2010, Akatsuki missed its [...]

An analysis of data collected by the Voyager 2 spacecraft and by ground-based telescopes limits the depths to which winds penetrate into Uranus and Neptune, informing the debate about these [...]

For many, our exploration of the cosmos seems to hinge on grand and singular theoretical observations and technological achievements such as those of Galileo and Einstein. We are fascinated by [...]

Explosions of plasma in the Sun's atmosphere can reach temperatures of nearly 100,000°C, much hotter than scientists had expected. The finding is one of several about the region between the [...]

NASA has revealed the first images from its latest solar observatory, the Interface Region Imaging Spectrograph (IRIS). The instrument was launched into orbit in June (see Nature 498, 279-280; 2013) [...]

The Mars Express spacecraft has now mapped the distributions of key minerals over almost all of the red planet's surface, the European Space Agency (ESA) announced on 3 June, a [...]