The master atomic clock ensemble at the in, which provides the time standard for the U.S. Department of Defense. The rack mounted units in the background are (formerly HP) 5071A caesium beam clocks.

Created by veterans from SEGA, BioWare, and Electronic Arts, ATOMIC SPACE COMMAND is a spaceship battle arena game launching on Steam Early Access October 13th. REACT replaces the 1960s vintage nuclear command and control system. A vacuous one-paragraph statement: 'Air Force Space Command has done a great.

The black units in the foreground are Microsemi (formerly Sigma-Tau) MHM-2010 hydrogen maser standards.An atomic clock is a device that uses a in the, or frequency in the or region of the of as a for its timekeeping element. Atomic clocks are the most accurate and frequency standards known, and are used as for international, to control the wave frequency of television broadcasts, and in such as.The principle of operation of an atomic clock is based on; it measures the electromagnetic signal that in atoms emit when they change. Early atomic clocks were based on at room temperature. Since 2004, more accurate atomic clocks first cool the atoms to near temperature by slowing them with lasers and probing them in in a microwave-filled cavity. An example of this is the atomic clock, one of the national primary time and frequency standards of the United States.The accuracy of an atomic clock depends on two factors: the first is temperature of the sample atoms—colder atoms move much more slowly, allowing longer probe times, the second is the frequency and of the electronic or hyperfine transition.

Higher frequencies and narrow lines increase the precision.National standards agencies in many countries maintain a network of atomic clocks which are intercompared and kept synchronized to an accuracy of 10 −9 seconds per day (approximately 1 part in 10 14). These clocks collectively define a continuous and stable time scale, the (TAI). For civil time, another time scale is disseminated, (UTC). UTC is derived from TAI, but has added from, to account for variations in the with respect to the. (right) and Jack Parry (left) standing next to the world's first caesium-133 atomic clock.The idea of using atomic transitions to measure time was suggested by in 1879., developed in the 1930s by, became the practical method for doing this. In 1945, Rabi first publicly suggested that atomic beam magnetic resonance might be used as the basis of a clock. The first atomic clock was an absorption line device at 23870.1 MHz built in 1949 at the U.S.

It was less accurate than existing, but served to demonstrate the concept. The first accurate atomic clock, a based on a certain transition of the atom, was built by and Jack Parry in 1955 at the in the UK. Calibration of the caesium standard atomic clock was carried out by the use of the astronomical time scale (ET). In 1967, this led the scientific community to redefine the in terms of a specific atomic frequency. Equality of the ET second with the (atomic clock) has been verified to within 1 part in 10 10. The SI second thus inherits the effect of decisions by the original designers of the scale, determining the length of the ET second.Since the beginning of development in the 1950s, atomic clocks have been based on the in,. The first commercial atomic clock was the, manufactured by the.

More than 50 were sold between 1956 and 1960. This bulky and expensive instrument was subsequently replaced by much smaller rack-mountable devices, such as the model 5060 caesium frequency standard, released in 1964.In the late 1990s, four factors contributed to major advances in clocks:. and trapping of atoms. So-called high-finesse for narrow laser line widths. Precision laser spectroscopy.

Convenient counting of optical frequencies using. Chip-scale atomic clocks, such as this one unveiled in 2004, are expected to greatly improve location.In August 2004, scientists demonstrated a. According to the researchers, the clock was believed to be one-hundredth the size of any other.

It requires no more than 125, making it suitable for battery-driven applications. This technology became available commercially in 2011.

Ion trap experimental optical clocks are more precise than the current caesium standard.In April 2015, NASA announced that it planned to deploy a (DSAC), a miniaturized, ultra-precise mercury-ion atomic clock, into outer space. NASA said that the DSAC would be much more stable than other navigational clocks. Mechanism.

This section needs additional citations for. Unsourced material may be challenged and removed.Find sources: – ( October 2017) Since 1968, the (SI) has defined the as the duration of 9 192 631 770 cycles of radiation corresponding to the transition between two energy levels of the ground state of the atom.

In 1997, the (CIPM) added that the preceding definition refers to a caesium atom at rest at a temperature of.This definition makes the caesium oscillator the primary standard for time and frequency measurements, called the. The definitions of other physical units, e.g., the and the, rely on the definition of the second.In this particular design, the time-reference of an atomic clock consists of an electronic oscillator operating at microwave frequency. The oscillator is arranged so that its frequency-determining components include an element that can be controlled by a feedback signal. The feedback signal keeps the oscillator tuned in with the frequency of the hyperfine transition of caesium or rubidium.The core of the atomic clock is a tunable containing a gas.

In a clock the gas emits (the gas ) on a hyperfine transition, the field in the cavity oscillates, and the cavity is tuned for maximum microwave amplitude. Alternatively, in a caesium or rubidium clock, the beam or gas absorbs microwaves and the cavity contains an electronic amplifier to make it oscillate.

For both types the atoms in the gas are prepared in one hyperfine state prior to filling them into the cavity. For the second type the number of atoms which change hyperfine state is detected and the cavity is tuned for a maximum of detected state changes.Most of the complexity of the clock lies in this adjustment process. The adjustment tries to correct for unwanted side-effects, such as frequencies from other electron transitions, temperature changes, and the spreading in frequencies caused. One way of doing this is to sweep the microwave oscillator's frequency across a narrow range to generate a modulated signal at the detector. The detector's signal can then be to apply feedback to control long-term drift in the radio frequency. In this way, the quantum-mechanical properties of the atomic transition frequency of the caesium can be used to tune the microwave oscillator to the same frequency, except for a small amount of experimental error. When a clock is first turned on, it takes a while for the oscillator to stabilize.

In practice, the feedback and monitoring mechanism is much more complex. Historical accuracy of atomic clocks fromA number of other atomic clock schemes used for other purposes. Rubidium standard clocks are prized for their low cost, small size (commercial standards are as small as 17 cm 3) and short-term stability. They are used in many commercial, portable and aerospace applications.

Hydrogen masers (often manufactured in Russia) have superior short-term stability compared to other standards, but lower long-term accuracy.Often, one standard is used to fix another. For example, some commercial applications use a rubidium standard periodically corrected by a receiver (see ). This achieves excellent short-term accuracy, with long-term accuracy equal to (and traceable to) the U.S. National time standards.The lifetime of a standard is an important practical issue. Modern rubidium standard tubes last more than ten years, and can cost as little as US$50. Caesium reference tubes suitable for national standards currently last about seven years and cost about US$35,000.

The long-term stability of hydrogen maser standards decreases because of changes in the cavity's properties over time.Modern clocks use to cool the atoms for improved precision.Power consumption The power consumption of atomic clocks varies with their size. Atomic clocks on the scale of one chip require less than 30; Primary frequency and time standards like the United States Time Standard atomic clocks, NIST-F1 and NIST-F2, use far higher power. Evaluated accuracy The evaluated accuracy u B reports of various primary frequency and time standards are by the International Bureau of Weights and Measures (BIPM).

Several frequency and time standards groups as of 2015 reported u B values in the 2 × 10 −16 to 3 × 10 −16 range.In 2011, the NPL-CsF2 caesium fountain clock operated by the, which serves as the United Kingdom primary frequency and time standard, was improved regarding the two largest sources of measurement uncertainties — distributed cavity phase and microwave lensing frequency shifts. In 2011 this resulted in an evaluated frequency uncertainty reduction from u B = 4.1 × 10 −16 to u B = 2.3 × 10 −16;— the lowest value for any primary national standard at the time. At this frequency uncertainty, the NPL-CsF2 is expected to neither gain nor lose a second in about 138 million ( 138 × 10 6) years. NIST physicists Steve Jefferts (foreground) and Tom Heavner with the NIST-F2 caesium fountain atomic clock, a civilian time standard for the United States.The caesium fountain clock operated by the, was officially launched in April 2014, to serve as a new U.S. Civilian frequency and time standard, along with the standard. The planned u B performance level of NIST-F2 is 1 × 10 −16. 'At this planned performance level the NIST-F2 clock will not lose a second in at least 300 million years.'

NIST-F2 was designed using lessons learned from NIST-F1. The NIST-F2 key advance compared to the NIST-F1 is that the vertical flight tube is now chilled inside a container of liquid nitrogen, at −193 °C (−315.4 °F). This cycled cooling dramatically lowers the background radiation and thus reduces some of the very small measurement errors that must be corrected in NIST-F1.The first in-house accuracy evaluation of NIST-F2 reported a u B of 1.1 × 10 −16.

However, a published scientific criticism of that NIST F-2 accuracy evaluation described problems in its treatment of distributed cavity phase shifts and the microwave lensing frequency shift, which is treated significantly differently than in the majority of accurate fountain clock evaluations. The next NIST-F2 submission to the BIPM in March, 2015 again reported a u B of 1.5 × 10 −16, but did not address the standing criticism. There have been neither subsequent reports to the BIPM from NIST-F2 nor has an updated accuracy evaluation been published.At the request of the Italian standards organization, NIST fabricated many duplicate components for a second version of NIST-F2, known as IT-CsF2 to be operated by the (INRiM), NIST's counterpart in Turin, Italy. As of February 2016 the IT-CsF2 caesium fountain clock started reporting a u B of 1.7 × 10 −16 in the BIPM reports of evaluation of primary frequency standards. Research. An experimental strontium based optical clock.Most research focuses on the often conflicting goals of making the clocks smaller, cheaper, more portable, more energy efficient, more, more stable and more reliable.The is an example of clock research.

Secondary representations of the second A list of frequencies recommended for secondary representations of the second is maintained by the International Bureau of Weights and Measures (BIPM) since 2006 and is. The list contains the frequency values and the respective standard uncertainties for the rubidium microwave transition and for several optical transitions. Further information:In March 2008, physicists at described a based on individual of. This clock was compared to NIST's ion clock.

These were the most accurate clocks that had been constructed, with neither clock gaining nor losing time at a rate that would exceed a second in over a billion years. In February 2010, NIST physicists described a second, enhanced version of the quantum logic clock based on individual of. Considered the world's most precise clock in 2010 with a fractional frequency inaccuracy of 8.6 × 10 −18, it offers more than twice the precision of the original. In July 2019, NIST scientists demonstrated such an Al+ Quantum-Logic clock with total uncertainty of 9.4 × 10 −19, which is the first demonstration of such a clock with uncertainty below 10 −18.The accuracy of experimental quantum clocks has since been superseded by experimental based on and.Optical clocks. May 2009- 's strontium optical atomic clock is based on neutral atoms.

Shining a blue laser onto ultracold strontium atoms in an optical trap tests how efficiently a previous burst of light from a red laser has boosted the atoms to an excited state. Only those atoms that remain in the lower energy state respond to the blue laser, causing the fluorescence seen here.The theoretical move from microwaves as the atomic 'escapement' for clocks to light in the optical range (harder to measure but offering better performance) earned and the in 2005. One of 2012's Physics Nobelists, is a pioneer in exploiting the properties of a single ion held in a trap to develop clocks of the highest stability.New technologies, such as femtosecond, optical lattices, and, have enabled prototypes of next-generation atomic clocks. These clocks are based on optical rather than microwave transitions. A major obstacle to developing an optical clock is the difficulty of directly measuring optical frequencies. This problem has been solved with the development of self-referenced mode-locked lasers, commonly referred to as femtosecond.

Before the demonstration of the frequency comb in 2000, techniques were needed to bridge the gap between radio and optical frequencies, and the systems for doing so were cumbersome and complicated. With the refinement of the, these measurements have become much more accessible and numerous optical clock systems are now being developed around the world.As in the radio range, absorption spectroscopy is used to stabilize an oscillator—in this case a laser. When the optical frequency is divided down into a countable radio frequency using a, the of the is also divided by that factor. Although the bandwidth of laser phase noise is generally greater than stable microwave sources, after division it is less.The primary systems under consideration for use in optical frequency standards are:. single ions isolated in an ion trap;. neutral atoms trapped in an optical lattice and.

atoms packed in a three-dimensional quantum gas optical lattice.These techniques allow the atoms or ions to be highly isolated from external perturbations, thus producing an extremely stable frequency reference.Atomic systems under consideration include +, +/2+, +/2+, +/3+, +, +/2+/3+, and +/3+. One of 's 2013 pair of ytterbium optical lattice atomic clocks.The rare-earth element ytterbium (Yb) is valued not so much for its mechanical properties but for its complement of internal energy levels. 'A particular transition in Yb atoms, at a wavelength of 578 nm, currently provides one of the world's most accurate optical atomic frequency standards,' said Marianna Safronova. The estimated amount of uncertainty achieved corresponds to a Yb clock uncertainty of about one second over the lifetime of the universe so far, 15 billion years, according to scientists at the Joint Quantum Institute (JQI) and the in December 2012.In 2013 optical lattice clocks (OLCs) were shown to be as good as or better than caesium fountain clocks. Two optical lattice clocks containing about 10 000 atoms of were able to stay in synchrony with each other at a precision of at least 1.5 × 10 −16, which is as accurate as the experiment could measure. These clocks have been shown to keep pace with all three of the caesium fountain clocks at the. There are two reasons for the possibly better precision.

Firstly, the frequency is measured using light, which has a much higher frequency than microwaves, and secondly, by using many atoms, any errors are averaged.Using atoms, a new record for stability with a precision of 1.6 ×10 −18 over a 7-hour period was published on 22 August 2013. At this stability, the two optical lattice clocks working independently from each other used by the research team would differ less than a second over the ( 13.8 ×10 9 years); this was 10 times better than previous experiments. The clocks rely on 10 000 ytterbium atoms cooled to 10 microkelvin and trapped in an optical lattice. A laser at 578 nm excites the atoms between two of their energy levels.

Having established the stability of the clocks, the researchers are studying external influences and evaluating the remaining systematic uncertainties, in the hope that they can bring the clock's accuracy down to the level of its stability. An improved optical lattice clock was described in a 2014 Nature paper.In 2015 evaluated the absolute frequency uncertainty of a optical lattice clock at 2.1 × 10 −18, which corresponds to a measurable for an elevation change of 2 cm (0.79 in) on planet Earth that according to JILA/NIST Fellow is 'getting really close to being useful for relativistic '.At this frequency uncertainty, this JILA optical lattice clock is expected to neither gain nor lose a second in more than 15 billion ( 15 × 10 9) years. JILA's 2017 three-dimensional (3-D) quantum gas atomic clock consists of a grid of light formed by three pairs of laser beams. A stack of two tables is used to configure optical components around a vacuum chamber. Shown here is the upper table, where lenses and other optics are mounted.

A blue laser beam excites a cube-shaped cloud of strontium atoms located behind the round window in the middle of the table. Strontium atoms fluoresce strongly when excited with blue light.In 2017 JILA reported an experimental 3D quantum gas strontium optical lattice clock in which strontium-87 atoms are packed into a tiny three-dimensional (3-D) cube at 1,000 times the density of previous one-dimensional (1-D) clocks, like the 2015 JILA clock. A synchronous clock comparison between two regions of the 3D lattice yielded a record level of synchronization of 5 × 10 −19 in 1 hour of averaging time.The 3D quantum gas strontium optical lattice clock's centerpiece is an unusual state of matter called a (a quantum gas for Fermi particles). The experimental data shows the 3D quantum gas clock achieved a precision of 3.5 × 10 −19 in about two hours. According to Jun Ye 'This represents a significant improvement over any previous demonstrations.' Ye further commented 'The most important potential of the 3D quantum gas clock is the ability to scale up the atom numbers, which will lead to a huge gain in stability.' And 'The ability to scale up both the atom number and coherence time will make this new-generation clock qualitatively different from the previous generation.'

Main article:One theoretical possibility for improving the performance of atomic clocks is to use a nuclear energy transition (between different ) rather than the which current atomic clocks measure. Most nuclear transitions operate at far too high a frequency to be measured, but in 2003, Ekkehard Peik and Christian Tamm noted that the exceptionally low excitation energy of is within reach of current frequency-measurement techniques, making a clock possible.

In 2012 it was shown, that a based on a single 229Th 3+ion could provide a total fractional frequency inaccuracy of 1.5 × 10 −19, which is better than existing 2019 atomic clock technology. Although it remains an unrealized theoretical possibility, as of 2019 significant progress toward the development of an experimental nuclear clock has been made.A nuclear energy transition offers the following potential advantages:. Higher frequency. All other things being equal, a higher-frequency transition offers greater stability for simple statistical reasons (fluctuations are averaged over more cycles per second). Immunity to environmental effects. Due to its small size and the shielding effects of the surrounding electrons, an atomic nucleus is much less sensitive to ambient electromagnetic fields than an electron.

Greater numbers of atoms. Because of the aforementioned immunity to ambient fields, it is not necessary to have the clock atoms well-separated in a dilute gas. In fact, it would be possible to take advantage of the and place the atoms in a solid, which would allow billions of atoms to be interrogated.Clock comparison techniques In June 2015, the European; the French; the German; and Italy's labs have started tests to improve the accuracy of current state-of-the-art satellite comparisons by a factor 10, but it will still be limited to one part in 1 × 10 −16. These 4 European labs are developing and host a variety of experimental optical clocks that harness different elements in different experimental set-ups and want to compare their optical clocks against each other and check whether they agree. In a next phase these labs strive to transmit comparison signals in the visible spectrum through fibre-optic cables. This will allow their experimental optical clocks to be compared with an accuracy similar to the expected accuracies of the optical clocks themselves. Some of these labs have already established fibre-optic links, and tests have begun on sections between Paris and Teddington, and Paris and Braunschweig.

Fibre-optic links between experimental optical clocks also exist between the American lab and its partner lab, both in but these span much shorter distances than the European network and are between just two labs. According to Fritz Riehle, a physicist at PTB, 'Europe is in a unique position as it has a high density of the best clocks in the world'.In August 2016 the French LNE-SYRTE in Paris and German PTB in Braunschweig reported the comparison and agreement of two fully independent experimental strontium lattice optical clocks in Paris and Braunschweig at an uncertainty of 5 × 10 −17 via a newly established phase-coherent frequency link connecting Paris and Braunschweig, using 1,415 (879 ) of telecom fibre-optic cable. The fractional uncertainty of the whole link was assessed to be 2.5 × 10 −19, making comparisons of even more accurate clocks possible. Applications The development of atomic clocks has led to many scientific and technological advances such as a system of precise global and regional, and applications in the, which depend critically on frequency and time standards. Atomic clocks are installed at sites of radio transmitters. They are used at some long wave and medium wave broadcasting stations to deliver a very precise carrier frequency.

Atomic clocks are used in many scientific disciplines, such as for long-baseline in. Global Navigation Satellite Systems The (GPS) operated by the US provides very accurate timing and frequency signals. A GPS receiver works by measuring the relative time delay of signals from a minimum of four, but usually more, GPS satellites, each of which has at least two onboard caesium and as many as two rubidium atomic clocks. The relative times are mathematically transformed into three absolute spatial coordinates and one absolute time coordinate.GPS Time (GPST) is a continuous time scale and theoretically accurate to about 14. However, most receivers lose accuracy in the interpretation of the signals and are only accurate to 100 ns.The GPST is related to but differs from TAI (International Atomic Time) and UTC (Coordinated Universal Time). GPST remains at a constant offset with TAI (TAI – GPST = 19 seconds) and like TAI does not implement leap seconds.

Periodic corrections are performed to the on-board clocks in the satellites to keep them synchronized with ground clocks. The GPS navigation message includes the difference between GPST and UTC. As of July 2015, GPST is 17 seconds ahead of UTC because of the leap second added to UTC on 30 June 2015. Receivers subtract this offset from GPS Time to calculate UTC and specific timezone values.The (GLONASS) operated by the provides an alternative to the Global Positioning System (GPS) system and is the second navigational system in operation with global coverage and of comparable precision. GLONASS Time (GLONASST) is generated by the GLONASS Central Synchroniser and is typically better than 1,000 ns. Unlike GPS, the GLONASS time scale implements leap seconds, like UTC.

Space Passive Hydrogen Maser used in ESA Galileo satellites as a master clock for an onboard timing systemThe is operated by the and and is near to achieving full operating global coverage. Galileo started offering global Early Operational Capability (EOC) on 15 December 2016, providing the third and first non-military operated Global Navigation Satellite System, and is expected to reach Full Operational Capability (FOC) in 2019. To achieve Galileo's FOC coverage constellation goal 6 planned extra satellites need to be added. Galileo System Time (GST) is a continuous time scale which is generated on the ground at the Galileo Control Centre in Fucino, Italy, by the Precise Timing Facility, based on averages of different atomic clocks and maintained by the Galileo Central Segment and synchronised with TAI with a nominal offset below 50 ns. According to the European GNSS Agency Galileo offers 30 ns timing accuracy.The March 2018 Quarterly Performance Report by the European GNSS Service Centre reported the UTC Time Dissemination Service Accuracy was ≤ 7.6 ns, computed by accumulating samples over the previous 12 months and exceeding the ≤ 30 ns target. Each Galileo satellite has two passive and two atomic clocks for onboard timing. The Galileo navigation message includes the differences between GST, UTC and GPST (to promote interoperability).The satellite navigation system is operated by the and is also near to achieving full-scale global coverage.

BeiDou Time (BDT) is a continuous time scale starting at 1 January 2006 at 0:00:00 UTC and is synchronised with UTC within 100 ns. BeiDou became operational in China in December 2011, with 10 satellites in use, and began offering services to customers in the region in December 2012. On 27 December 2018 the BeiDou Navigation Satellite System started to provide global services with a reported timing accuracy of 20 ns. The BeiDou global navigation system should be finished by 2020. Time signal radio transmitters A is a clock that automatically synchronizes itself by means of government radio received by a. Many retailers market radio clocks inaccurately as atomic clocks; although the radio signals they receive originate from atomic clocks, they are not atomic clocks themselves.Normal low cost consumer grade receivers solely rely on the amplitude-modulated time signals and use narrow band receivers (with 10 Hz bandwidth) with small ferrite and circuits with non optimal digital signal processing delay and can therefore only be expected to determine the beginning of a second with a practical accuracy uncertainty of ± 0.1 second. This is sufficient for radio controlled low cost consumer grade clocks and watches using standard-quality for timekeeping between daily synchronization attempts, as they will be most accurate immediately after a successful synchronization and will become less accurate from that point forward until the next synchronization.Instrument grade time receivers provide higher accuracy.

Such devices incur a transit delay of approximately 1 for every 300 kilometres (186 mi) of distance from the. Many governments operate transmitters for time-keeping purposes.See also.

publisher: No, You Shut Up!

Game mode: multiplayer

Multiplayer mode: Internet

game release date for PC:

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Development of the game Atomic Space Command for PC have been suspended and will not be continued.

Atomic Space Command for PCis a multiplayer action game set in space.It was developed by No, You Shut Up! – a studio established by ex-employees of Maxis who worked on games like SimCity and The Sims.

Mechanics

Our task in Atomic Space Command for PC is to dominate an entire solar system with the help of our spaceships. Controls were designed in a way that requires multiple players to achieve full functionality and effectiveness of our ship. Gameplay focuses on cooperation with our teammates and rivalry with other groups of pilots. Participants are divided into two teams, each of them consisting of many space ships.

We begin our adventure by choosing our basic space ship model. Later, we can use our rewards to upgrade and modify our ships and build new ones. Rivalry in the game focuses on taking control over planets. Doing so allows us to build bases on them that generate victory points and resources. It is a variation about the Capture The Flage game mode with an additional pinch of strategy.

Our space ships have multiple subsystems. Managing all of them requires a lot of effort. We have to assign our crew members to specific tasks, manage energy resources, and decide about the order of repairs. In addition to other players, there are some NPcs aboard our ships. We choose them from a rich base of characters. It is possible to steer our ship by ourselves, but doing so with other players is much more effective and fun.

Expectations: 7.3 / 10 calculated out of 3 players' votes.

age requirements: everyone