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Showing papers on "Trojan published in 2007"


Proceedings ArticleDOI
20 May 2007
TL;DR: These results show that Trojans that are 3-4 orders of magnitude smaller than the main circuit can be detected by signal processing techniques and provide a starting point to address this important problem.
Abstract: Hardware manufacturers are increasingly outsourcing their IC fabrication work overseas due to their much lower cost structure. This poses a significant security risk for ICs used for critical military and business applications. Attackers can exploit this loss of control to substitute Trojan ICs for genuine ones or insert a Trojan circuit into the design or mask used for fabrication. We show that a technique borrowed from side-channel cryptanalysis can be used to mitigate this problem. Our approach uses noise modeling to construct a set of fingerprints/or an IC family utilizing side- channel information such as power, temperature, and electromagnetic (EM) profiles. The set of fingerprints can be developed using a few ICs from a batch and only these ICs would have to be invasively tested to ensure that they were all authentic. The remaining ICs are verified using statistical tests against the fingerprints. We describe the theoretical framework and present preliminary experimental results to show that this approach is viable by presenting results obtained by using power simulations performed on representative circuits with several different Trojan circuitry. These results show that Trojans that are 3-4 orders of magnitude smaller than the main circuit can be detected by signal processing techniques. While scaling our technique to detect even smaller Trojans in complex ICs with tens or hundreds of millions of transistors would require certain modifications to the IC design process, our results provide a starting point to address this important problem.

741 citations


Journal ArticleDOI
TL;DR: In this article, the authors examined the sensitivity of transit timing observations for detecting Trojan companions to transiting extrasolar planets and demonstrated that this method offers the potential to detect terrestrial-mass Trojans using existing ground-based observatories.
Abstract: Theoretical studies predict that Trojans are likely a frequent by-product of planet formation and evolution. We examine the sensitivity of transit timing observations for detecting Trojan companions to transiting extrasolar planets. We demonstrate that this method offers the potential to detect terrestrial-mass Trojans using existing ground-based observatories. We compare the transit timing variation (TTV) method with other techniques for detecting extrasolar Trojans and outline the future prospects for this method.

131 citations


Journal ArticleDOI
TL;DR: In this paper, the authors analyzed 1187 observations of about 860 unique candidate Jovian Trojan asteroids listed in the 3rd release of the Sloan Digital Sky Survey (SDSS) Moving Object Catalogue.
Abstract: We analyse 1187 observations of about 860 unique candidate Jovian Trojan asteroids listed in the 3rd release of the Sloan Digital Sky Survey (SDSS) Moving Object Catalogue. The sample is complete at the faint end to r = 21.2 mag (apparent brightness) and H = 13.8 (absolute brightness, approximately corresponding to 10 km diameter). A subset of 297 detections of previously known Trojans were used to design and optimize a selection method based on observed angular velocity that resulted in the remaining objects. Using a sample of objects with known orbits, we estimate that the candidate sample contamination is about 3 per cent. The well-controlled selection effects, the sample size, depth and accurate five-band UV‐ IR photometry enabled several new findings and the placement of older results on a firmer statistical footing. We find that there are significantly more asteroids in the leading swarm (L4) than in the trailing swarm (L5): N(L4)/N(L5) = 1.6 ± 0.1, independently of limiting object’s size. The overall counts normalization suggests that there are about as many Jovians Trojans as there are main-belt asteroids down to the same size limit, in agreement with earlier estimates. We find that Trojan asteroids have a remarkably narrow colour distribution (root mean scatter of only ∼0.05 mag) that is significantly different from the colour distribution of the main-belt asteroids. The colour of Trojan asteroids is correlated with their orbital inclination, in a similar way for both swarms, but appears uncorrelated with the object’s size. We extrapolate the results presented here and estimate that the Large Synoptic Survey Telescope will determine orbits, accurate colours and measure light curves in six photometric bandpasses for about 100 000 Jovian Trojan asteroids.

117 citations


Journal ArticleDOI
TL;DR: In this article, the authors analyzed 1187 observations of about 860 unique candidate Jovian Trojan asteroids listed in the 3rd release of Sloan Digital Sky Survey (SDSS) Moving Object Catalog.
Abstract: We analyze 1187 observations of about 860 unique candidate Jovian Trojan asteroids listed in the 3rd release of Sloan Digital Sky Survey (SDSS) Moving Object Catalog. The sample is complete at the faint end to r=21.2 mag (apparent brightness) and H=13.8 (absolute brightness, approximately corresponding to 10 km diameter). A subset of 297 detections of previously known Trojans were used to design and optimize a selection method based on observed angular velocity that resulted in the remaining objects. Using a sample of objects with known orbits, we estimate that the candidate sample contamination is about 3%. The well-controlled selection effects, the sample size, depth and accurate five-band UV-IR photometry enabled several new findings and the placement of older results on a firmer statistical footing. We find that there are significantly more asteroids in the leading swarm (L4) than in the trailing swarm (L5): N(L4)/N(L5)=1.6$\pm$0.1, independently of limiting object's size. The overall counts normalization suggests that there are about as many Jovians Trojans as there are main-belt asteroids down to the same size limit, in agreement with earlier estimates. We find that Trojan asteroids have a remarkably narrow color distribution (root-mean-scatter of only $\sim$0.05 mag) that is significantly different from the color distribution of the main-belt asteroids. The color of Trojan asteroids is correlated with their orbital inclination, in a similar way for both swarms, but appears uncorrelated with the object's size. We extrapolate the results presented here and estimate that Large Synoptic Survey Telescope will determine orbits, accurate colors and measure light curves in six photometric bandpasses for about 100,000 Jovian Trojan asteroids.

84 citations


Journal ArticleDOI
TL;DR: In this article, the authors studied the dynamical possibility that a terrestrial planet can exist in a 1:1 mean motion resonance with a Jovian-like planet, and they compiled a catalogue of hypothetical habitable Trojan planets, to make a stability forecast for further extrasolar planetary systems discovered in the future.
Abstract: Aims. In this work we study the dynamical possibility in extrasolar planetary systems that a terrestrial planet can exist in 1:1 mean motion resonance with a Jovian-like planet. We compiled a catalogue of hypothetical habitable Trojan planets, to be able to make a stability forecast for further extrasolar planetary systems discovered in the future. When speaking of habitability we also took the influence of the spectral type of the central star into account. Methods. We integrated some 10 6 orbits of fictitious Trojans around the Lagrangian points for up to 10 7 orbital periods of the primary bodies and checked the stability of the orbital elements and their chaoticity with the aid of the Lyapunov characteristic indicator and maximum eccentricity. The computations were carried out using the dynamical model of the elliptic, restricted three-body problem that consists of a central star, a gas giant moving in the habitable zone, and a hypothetical (massless) terrestrial planet. Results. Our investigations have shown that 7 exoplanetary systems can harbour habitable Trojan planets with stable orbits (HD 93083, HD 17051, HD 28185, HD 27442, HD 188015, HD 99109, and HD 221287, which is a recently discovered system). The comparison of the investigated systems with our catalogue showed matching results, so that we can use the catalogue in practice.

46 citations


Journal ArticleDOI
TL;DR: The Jovian Trojans likely formed beyond the snow line and so may contain considerable amounts of water ice as discussed by the authors, and they have been observed to show possible weak absorptions at 1.7 and 2.3 μm, respectively.
Abstract: The Jovian Trojans likely formed beyond the snow line and so may contain considerable amounts of water ice. We seek near-infrared spectroscopic evidence for the 1.5 and 2.0 μm water ice bands in the Trojans. Our sample is focused on objects identified in previous measurements as being of special interest. The unusual Trojan (4709) Ennomos has a geometric albedo significantly above the mean Trojan albedo, perhaps because a recent impact has coated part of the surface with freshly excavated ice. Trojans (911) Agamemnon, (617) Patroclus, (1143) Odysseus, and (2797) Teucer were also observed. These objects have been independently reported to show possible weak absorptions at 1.7 and 2.3 μm, respectively. If real, the latter features may be due to organic materials present on the surfaces. However, all five targets appear spectrally featureless, even in our highest signal-to-noise ratio data. Simple models consisting of mixtures of water ice and a spectrally featureless material were used to quantify the limits to surface ice.

46 citations


Journal ArticleDOI
15 Dec 2007-Icarus
TL;DR: In this paper, the authors obtained infrared (0.8-2.5 μm) spectroscopy of the two largest L5 Mars Trojans, and confirmed and extended the results of Rivkin et al.

45 citations


Journal ArticleDOI
TL;DR: In this article, the authors used the results of extensive numerical integrations of orbits for a fine grid in initial conditions around the points L 4 and L 5 and analyzed the stability of the individual orbits.
Abstract: The area of stable motion for fictitious Trojan asteroids around Neptune's equilateral equilibrium points is investigated with respect to the size of the regions and their shape, subject to the inclination of the asteroid's orbit. For this task, we used the results of extensive numerical integrations of orbits for a fine grid in initial conditions around the points L 4 and L 5 and analysed the stability of the individual orbits. Our basic dynamical model was the outer Solar system (Jupiter, Saturn, Uranus and Neptune) but for comparison reasons also simpler ones were tested. We integrated in our models the equations of motion for some 5 x 10 5 orbits of fictitious Trojans in the vicinity of the stable equilibrium points up to 10 9 yr. According to the three-dimensional model, the initial inclination of the asteroids' orbit was also varied in the range 0° < i < 60°. Using on one side a fine grid of initial conditions, the semimajor axis versus perihelion of the fictitious object and, on the other side, the proper eccentricity e p versus the libration width D f , we compiled stability maps separately for L 4 and L 5 . In addition, we computed the escape-times of the individual objects and plotted the number of escapers per time-interval of 5 x 10 6 yr for different initial inclinations. Finally, integrations of the equations of motion in different dynamical models shed light on the reason of the asymmetry of the stability behaviour of orbits close to the two equilateral equilibrium points of Neptune. For low-inclined Trojan orbits, the stability area around L 4 and L 5 disappeared after some 10 8 yr, and for larger inclinations of the Trojans the stability area survived for the time-interval of integration of 10 9 yr. The largest stable regions exist for Neptune Trojans with 20° < i < 50°. The somewhat interesting asymmetry in the size and the shape of the preceding and following Lagrange points, which exist for Neptune Trojans, was confirmed, and was found to be caused mostly by the couple Saturn-Uranus.

41 citations


Journal ArticleDOI
TL;DR: In this article, an optical light-curve survey of 114 Jovian Trojan asteroids was conducted to determine the fraction of contact binaries, which led to the discovery of two Trojan asteroids, (17365 and (29314), displaying large lightcurve ranges (~1 mag) and long rotation periods consistent with a contact binary nature.
Abstract: We present the results of an optical light-curve survey of 114 Jovian Trojan asteroids conducted to determine the fraction of contact binaries. Sparse sampling was used to assess the photometric range of the asteroids, and those showing the largest ranges were targeted for detailed follow-up observations. This survey led to the discovery of two Trojan asteroids, (17365) and (29314), displaying large light-curve ranges (~1 mag) and long rotation periods (<2 rotations day-1) consistent with a contact binary nature. The optical light curves of both asteroids are well matched by Roche binary equilibrium models. Using these binary models, we find low densities of ~600 and 800 kg m-3, suggestive of porous interiors. The fraction of contact binaries is estimated to be between 6% and 10%, comparable to the fraction in the Kuiper Belt. The total binary fraction in the Trojan clouds (including both wide and close pairs) must be higher.

39 citations


Journal ArticleDOI
TL;DR: In this paper, the authors analyzed the collisional and dynamical evolution of the population of L 4 Jovian Trojans and found that the contribution of the Trojan asteroids to the current populations of Centaurs and Jupiter-family comets is negligible.
Abstract: Aims. In this paper, we analyze the collisional and dynamical evolution of the population of L 4 Jovian Trojans. Methods. To do this, we test different collisional parameters and include a dynamical treatment, taking into account the stability and instability zones of the L 4 Trojan swarm. This procedure allows us to estimate the size distribution of the L 4 Trojans, to study their mean collisional lifetimes, to analyze the formation of families, to obtain ejection rates of Trojan fragments and to discuss their possible contribution to the current populations of Centaurs and Jupiter-family comets. Results. Our estimates of the L 4 Trojan cumulative size distribution show waves that propagate from diameters of ~0.1 to ~80 km around the values derived from optical surveys. On the other hand, the mean collisional lifetimes obtained from our simulations indicate that the large Trojan asteroids have likely survived without being catastrophically fragmented over the age of the Solar System. With regards to the Trojan removal, we calculate a maximum ejection rate of Trojan fragments from L 4 of ~50 objects larger than 1 km of diameter per Myr, which results to be significantly smaller than values previously published. Such estimates allow us to infer that the contribution of the Trojan asteroids to the current populations of Centaurs and Jupiter-family comets is negligible. In addition, our results are in agreement with the formation of few Trojan families in the L 4 swarm. On the other hand, we infer that the current orbital distribution of the Trojan asteroids does not offer a strong constraint on the dynamical origin of this population.

31 citations


01 Jan 2007
TL;DR: A new tool for analysing banking trojans is implemented, which has run this tool on thousands of recent malware samples to get an idea of how common these banking Trojans are, the current trends, the geographical distribution of this problem, and what the targets are.
Abstract: It is obvious that as more and more money moves online, criminals who want to steal that money are moving online as well. Since banks no longer have large sums of money in their vaults and bank robbery has several inherent risks, criminals have found a lucrative and a much lower-risk business in online crime. Email-based phishing has been the first echelon of this change, but the situation is already changing again. Online banks have begun to improve their security and authentication methods. This will very much reduce the effectiveness of phishing that is based on emails and fraudulent sites. There is a clear demand for better solutions in the world of crime. The second echelon of online bank fraud is banking trojans. These trojans infect the computer of an online bank customer. The trojan has visibility to everything the customer does and can use his authenticated banking session to steal his money. Also, a key difference from email-based phishing is that the victim is doing nothing wrong; he is just going to his bank and doing his business, as he should. These attackers are making a lot of money. Relatively few of them are caught, so the problem is only going to get worse. To better understand this problem and its size, we have implemented a new tool for analysing banking trojans. We have run this tool on thousands of recent malware samples to get an idea of how common these banking trojans are, the current trends, the geographical distribution of this problem, and what the targets are. This paper presents our findings.

Journal ArticleDOI
TL;DR: The role of the Trojan War in epic and tragic poetry is well known, its role in comic poetry less so as mentioned in this paper, which may explain why the war did feature in a number of ancient comedies, not only because fighting and death are subjects unlikely to give rise to much hilarity, but also because one tends to associate comedy with a type of subject matter markedly different from that of tragedy and epic.
Abstract: The role of the Trojan War in epic and tragic poetry is well known, its role in comic poetry less so. Yet the war did feature in a number of ancient comedies. This fact might seem surprising, not only because fighting and death are subjects unlikely to give rise to much hilarity, but also because one tends to associate comedy with a type of subject matter markedly different from that of tragedy and epic. Nevertheless, many comedies did adopt mythological subjects,1 and even those set in present-day Athens might allude to myth. This article aims to examine the Trojan War theme as it appears in Old Comedy, and to explain its function with reference to the social and intellectual context of late fifth-century Greece. Thinking about this topic may also open up certain larger questions about the genre of comedy and its relation to myth and tragedy. First, a caveat: there is no extant comedy of the ‘mythological’ type, and for the most part one has to deal with sparse fragments and testimonia.2 This makes it hard to be confident about the manner in which comedians handled the myth. Not only the content but also the date of most plays is unknown. Thus a degree of imagination and guesswork is called for—which, though unprovable, may allow one to situate otherwise unrewarding shards within a satisfying conceptual framework. And there is considerable room for optimism. A number of comedies demonstrably made use of the Trojan War theme—including Aristophanes’ Acharnians, Birds and Daedalus, Cratinus’ Dionysalexandros and Nemesis, Eupolis’ Prospaltians, and Plato’s Menelaus— and for some of these plays the evidence is reasonably substantial. Apart from a few insignificant passing references, and a few allusions which are too insubstantial to interpret,3 the evidence adds up to a remarkably consistent picture. In the first place, it appears that the comedians were interested in the Trojan War less for 412


Journal ArticleDOI
15 Dec 2007-Icarus
TL;DR: In this paper, the authors observed the Mars Trojan Asteroids (5261) Eureka and (101429) 1998 VF 31 and the candidate Mars Trojan 2001 FR 127 at 11.2 and 18.1 microns using the Gemini North telescope.

Journal ArticleDOI
TL;DR: In this paper, the existence of Earth-like Trojan terrestrial planets in stable orbits in the habitable zone of the G5 host star in the Earth-Moon system was verified with the aid of the Fast Lyapunov Indicator.
Abstract: Aims. It turned out recently that, in addition to a large planet with a semimajor axis a ∼ 1 AU and a low eccentricity (e ∼ 0.07), the extrasolar planetary system HD 108874 harbors another massive planet with 2.43 AU < a < 2.93 AU. The inner planet is orbiting the G5 host star in the habitable zone (=HZ); so that we could established stable regions for Earth-like Trojan planets. Methods. We integrated some 10 5 orbits of fictitious Trojans around the Lagrangian points for up to 107 years and checked the stability of the orbital elements and their chaoticity with the aid of the Fast Lyapunov Indicator. Results. It turns out that this multiplanetary system is the first one where - with the uncertainties in eccentricity and semimajor axes of the outer planet - the existence of Trojan terrestrial planets in stable orbits in the HZ is possible for some combinations of the orbital parameters.

Journal ArticleDOI
TL;DR: The Theater of Troy as mentioned in this paper is a play on three meanings of the word “theater,” which is a theater of war offering a synoptic vision of a military.
Abstract: an ugly secret, sometimes betrayed by the sudden jerk of the head of the dozing reader, admits in muffled tones that a substantial proportion of what is recognized as great literature is boring. The definitive work on the tedium of great art has yet to be written, but it would doubtless include lengthy chapters on The Fairy Queen, La Nouvelle Héloïse, Wilhelm Meister, I Promessi Sposi, Balzac’s 50 page description of a card game played in only one area of Normandy—I’ll leave my readers to supply their own candidates for full treatment. Wretch that I am, I have to admit that I never got past page 37 of Broch’s Death of Virgil. Now, among Greek texts frequently appearing as finalists for The Most Boring Award are undoubtedly the Catalogue of Ships and the so-called Battle Books of the Iliad. My title is Homer’s Theater of Troy with a play on three meanings of the word “theater”; first, a theater of war offering a synoptic vision of a military

Journal ArticleDOI
TL;DR: In this article, the authors analyzed the dynamics of Jupiter Trojans during the resonance crossing and found that orbital instability is not confined to the central 2:1 resonance region but occurs in a more extended region where secular and secondary resonances perturb the Trojan orbits while the planets approach, cross and leave the 2: 1 resonance.
Abstract: In the early phase of the Solar system evolution, while the outer planets migrated due to their interaction with a planetesimal disc, Jupiter may have crossed the 2:1 mean motion resonance with Saturn. It is well known that this dynamical event has profound consequences on the evolution of an alleged initial Trojan population of Jupiter. In this paper, we analyse in details the dynamics of Jupiter Trojans during the resonance crossing. We find that orbital instability is not confined to the central 2:1 resonance region but occurs in a more extended region where secular and secondary resonances perturb the Trojan orbits while the planets approach, cross and leave the 2:1 resonance. In addition, Jupiter and Saturn are locked after the resonance crossing in an apsidal corotation which has an additional destabilizing effect on Trojans. The synergy of the secular resonance, secondary resonances and apsidal corotation is needed to fully remove an initial Trojan population. New Trojans can be temporarily captured from the planetesimal disc while Jupiter crosses this extended instability region. After the disappearance of major secondary resonances, the secular resonance and the break of the apsidal corotation, the temporarily captured Trojans are locked and can remain stable over long timescales .

Journal ArticleDOI
TL;DR: In this article, the formation and evolution of the highly inclined orbit of Neptune Trojan 2005 TN 53 was explored with numerical simulations, and a possible mechanism for the origin of the high-inclination Neptune Trojans as captured into the Trojan-type orbits by an initially eccentric Neptune during its eccentricity damping and rapid inward migration, then migrating to the present locations locked in Neptune's 1:1 mean motion resonance.
Abstract: Aims. We explore the formation and evolution of the highly inclined orbit of Neptune Trojan 2005 TN 53 . Methods. With numerical simulations, we investigated a possible mechanism for the origin of the high-inclination Neptune Trojans as captured into the Trojan-type orbits by an initially eccentric Neptune during its eccentricity damping and rapid inward migration, then migrating to the present locations locked in Neptune's 1:1 mean motion resonance. Results. Two 2005 TN 53 -type Trojans out of our 2000 test particles were produced with inclinations above 20°, moving on tadpole orbits librating around Neptune's leading Lagrange point.

Journal ArticleDOI
TL;DR: In this paper, the spectral slope and color distributions of Jupiter Trojans were analyzed using a sample of data from the Moving Object Catalogue of the Sloan Digital Sky Survey, together with spectra obtained from several surveys.
Abstract: We present a comparative analysis of the spectral slope and color distributions of Jupiter Trojans, with particular attention to asteroid families. We use a sample of data from the Moving Object Catalogue of the Sloan Digital Sky Survey, together with spectra obtained from several surveys. A first sample of 349 observations, corresponding to 250 Trojan asteroids, were extracted from the Sloan Digital Sky Survey, and we also extracted from the literature a second sample of 91 spectra, corresponding to 71 Trojans. The spectral slopes were computed by means of a least-squares fit to a straight line of the fluxes obtained from the Sloan observations in the first sample, and of the rebinned spectra in the second sample. In both cases the reflectance fluxes/spectra were renormalized to 1 at 6230 $\textrmA$. We found that the distribution of spectral slopes among Trojan asteroids shows a bimodality. About 2/3 of the objects have reddish slopes compatible with D-type asteroids, while the remaining bodies show less reddish colors compatible with the P-type and C-type classifications. The members of asteroid families also show a bimodal distribution with a very slight predominance of D-type asteroids, but the background is clearly dominated by the D-types. The L4 and L5 swarms show different distributions of spectral slopes, and bimodality is only observed in L4. These differences can be attributed to the asteroid families since the backgraound asteroids show the same slope distribtuions in both swarms. The analysis of individual families indicates that the families in L5 are taxonomically homogeneous, but in L4 they show a mixture of taxonomic types. We discuss a few scenarios that might help to interpret these results.

Book ChapterDOI
Ken Thompson1
01 Jan 2007
TL;DR: To what extent should one trust a statement that a program is free of Trojan horses?
Abstract: To what extent should one trust a statement that a program is free of Trojan horses? Perhaps it is more important to trust the people who wrote the software.

Journal ArticleDOI
01 Oct 2007
TL;DR: In this paper, the authors examined the motion of fictitious Trojan planets close to the equilateral Lagrangean equilibrium points in extrasolar planetary systems and showed that they may survive only for e < 0.25.
Abstract: Abstract In this article we examine the motion of fictitious Trojan planets close to the equilateral Lagrangean equilibrium points in extrasolar planetary systems. Whether there exist stable motion in this area or not depends on the massratio of the primariy bodies in the restricted three body problem, namely the host star and the gasgiant. Taking into account also the eccentricity of the primaries we show via results of extensive numerical integrations that Trojan planets may survive only for e < 0.25. We also show first results of a mapping in the 1:1 resonance with a gas giant on an eccentric orbit which is applied to the extrasolar planetary systems HD 17051. We furthermore study the influence of an additional outer planet which perturbs the motion of the gasgiant as well as the Trojan cloud around its L4 Lagrangean point.

Journal ArticleDOI
Olga Trivailo1
TL;DR: In this paper, the dynamics and stability of a satellite were studied under multiple Trojan asteroids influence through the use of a numerical simulator developed in MATLAB, considering the effects of gravitational forces exerted by the asteroids themselves, simulating the resulting insignificant influence of the Trojan asteroids on a satellite placed at the triangular Lagrange points.

Proceedings ArticleDOI
01 Feb 2007
TL;DR: In this article, the authors presented a new class of planetary exploration missions that is enabled by the combination of the three technologies of advanced radioisotope power systems, electric propulsion, and expendable launch vehicles.
Abstract: This paper presents an example of a new class of planetary exploration missions that is been enabled by the combination of the three technologies of advanced radioisotope power systems, electric propulsion, and expendable launch vehicles These PARIS (Planetary Access with Radioisotope Ion‐drive System) missions are optimized for rendezvous with outer solar system bodies in shallow gravity wells They are low‐thrust missions that are launched to a high C3 and use their electric propulsion systems to slow them to enable orbit insertion or landing on the target body The PARIS spacecraft can be powered by traditional Radioisotope Thermoelectric Generators (RTGs), but will benefit greatly from the improved power‐to‐mass ratio of Stirling radioisotope generators (SRGs) that results from their high conversion efficiency These New‐Frontiers class missions can carry a significant science payload to the Jovian Trojan asteroids The Trojans are very primitive bodies located near the Jovian L4 and L5 Lagrange points The PARIS to Hektor mission can reach the asteroids in less than 5 years, orbit 624 Hektor, the largest of the Jovian Trojans, and go on to orbit at least one other nearby object There are estimated to be more than 105 Jovian Trojans greater than 1 km in diameter The PARIS to Hektor spacecraft has a candidate payload that includes wide‐field and narrow‐field cameras, a UV‐Vis‐IR spectrograph, gamma‐ray and neutron spectrometers, and plasma and energetic particle spectrometers The power system generates about 900 W and the launch mass is slightly less than 1000 kg The trip time is 5 years if “classic” GPHS RTGs are used for power Next generation Stirling radioisotope generators (SRGs), with a demonstrated thermal conversion efficiency of > 30% and an estimated specific power of > 8W/kg would reduce the travel time to about 4 years

Journal ArticleDOI
TL;DR: If you are attacked by a targeted trojan, your confidential information, product designs, plans, R&D data or other secrets could end up in the hands of extorters or competitors.
Abstract: Targeted trojans are firmly on the threat roadmap and their evolution is a compelling one. If you were a criminal mastermind and you wanted to steal secrets from a company, the easiest way to do it is with a custom-written virus or trojan aimed at an individual within the target company. If you are attacked by a targeted trojan, your confidential information, product designs, plans, R&D data or other secrets could end up in the hands of extorters or competitors. It is simply industrial espionage via malicious code.

Journal ArticleDOI
TL;DR: In this article, the authors examined the sensitivity of transit timing observations for detecting Trojan companions to transiting extrasolar planets and demonstrated that this method offers the potential to detect terrestrial-mass Trojans using existing ground-based observatories.
Abstract: Theoretical studies predict that Trojans are likely a frequent byproduct of planet formation and evolution. We examine the sensitivity of transit timing observations for detecting Trojan companions to transiting extrasolar planets. We demonstrate that this method offers the potential to detect terrestrial-mass Trojans using existing ground-based observatories. We compare the transit timing variation (TTV) method with other techniques for detecting extrasolar Trojans and outline the future prospects for this method.


Journal Article
TL;DR: A defense against Trojan horse system based on restricted token is stated and the experiment result validates the feasibility and availability of this system.
Abstract: According to the analysis of Trojan horse attack patterns,implant methods,the security model of windows and limitations of the Trojan horse detection technologies at present,A defense against Trojan horse system based on restricted token is stated in this paper.Combined with constructing the secure work environment,auditing the startup of applications and restraining the malicious action of Trojan horse.The design of process environment control module,service manager module,register monitoring and anomaly diagnose module are focused on.At last,the experiment result validates the feasibility and availability of this system.

Journal Article
TL;DR: The paper presents an approach to detect the existence of system call hooks set by Trojan horses based on the locality and determinacy of execution flows, and the analysis of system function call labs in both user and kernel levels, then designs and realizes corresponding prototype.
Abstract: Trojan horses design essence lies in hijacking execution routine,and most of current detection methods fail to completely identify such ever-increasingly covert Trojan horses.The paper presents an approach to detect the existence of system call hooks set by Trojan horses based on the locality and determinacy of execution flows,and the analysis of system function call labs in both user and kernel levels,then designs and realizes corresponding prototype.Compared with current detections,the method offsets the deficiency in identifying unknown Trojan horses with more complete detection results.


Journal ArticleDOI
TL;DR: In this paper, the authors present the results of an optical lightcurve survey of 114 Jovian Trojan asteroids conducted to determine the fraction of contact binaries, which led to the discovery of two Trojan asteroids, (17365 and (29314) displaying large light-curve ranges (~1 magnitude) and long rotation periods consistent with a contact binary nature.
Abstract: We present the results of an optical lightcurve survey of 114 Jovian Trojan asteroids conducted to determine the fraction of contact binaries. Sparse-sampling was used to assess the photometric range of the asteroids and those showing the largest ranges were targeted for detailed follow-up observations. This survey led to the discovery of two Trojan asteroids, (17365) and (29314) displaying large lightcurve ranges (~1 magnitude) and long rotation periods (< 2 rotations per day consistent with a contact binary nature. The optical lightcurves of both asteroids are well matched by Roche binary equilibrium models. Using these binary models, we find low densities of ~600 kg/m^3 and 800 kg/m^3, suggestive of porous interiors. The fraction of contact binaries is estimated to be between 6% and 10%, comparable to the fraction in the Kuiper Belt. The total binary fraction in the Trojan clouds (including both wide and close pairs) must be higher.