PoS(FRAPWS2018)084 https://pos.sissa.it/ ∗ [email protected] [email protected] [email protected] [email protected] [email protected] Speaker. Very Long Baseline Interferometry (VLBI) has beencame developing to for more a than new half level aRadioastron after century mission and the that emergence is of led the byis possibility Astro the to Space only launch Center 10-m radio was space telescope launchedEarth radio into in interferometer telescope July, space. 2011 operating together and for with currently more moreAGN&QSO than than sources 6 40 with years. the ground highest It telescopes, angulartory operates observing resolution. as of pulsars, a Millimetron Astro masers, is Space- Space the Center nextwavelength ranges. to space The observa- be unprecedented sensitivity addressed and for angularscope, resolution the operating of far the in cooled a infrared, 10-m L2 tele- sub-millimeter orbit,key and will scientific millimeter provide problems the in astronomical astronomy and communitymodes: astrophysics. an Space-Earth opportunity The VLBI to observatory element will solve and have single two dish observing telescope. ∗ Copyright owned by the author(s) under the terms of the Creative Commons c Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). Frontier Research in Astrophysics - III (FRAPWS2018) 28 May - 2 June 2018 Mondello (Palermo), Italy Kostenko V. I. Astro Space Center, Lebedev Physical Inst.E-mail: RAS, Profsoyuznaya 84/32, 117997 Moscow, Russia, Schekinov Yu. A. Astro Space Center, Lebedev Physical Inst.E-mail: RAS, Profsoyuznaya 84/32, 117997 Moscow, Russia, Likhachev S. F. Astro Space Center, Lebedev Physical Inst.E-mail: RAS, Profsoyuznaya 84/32, 117997 Moscow, Russia, Andrianov A. S. Astro Space Center, Lebedev Physical Inst.E-mail: RAS, Profsoyuznaya 84/32, 117997 Moscow, Russia, Rudnitskiy A. G. Astro Space Center, Lebedev Physical Inst.E-mail: RAS, Profsoyuznaya 84/32, 117997 Moscow, Russia, The Current and Future of GroundScience. and Space-VLBI PoS(FRAPWS2018)084 ]. 6 , 5 Rudnitskiy A. G. at C-band and 104 as µ at K-band, 19 as µ ]. 3 , 1 2 ]. 4 ]. It has four frequency bands: 0.327 GHz (P-band), 1.665 GHz 7 ]. This provides an ability to reprocess the raw data of any observation ]. Later, driven by the Radioastron revealed scattering disk substructure, 6 9 , 8 ], or a high sensitivity compact millimeter array ALMA, the project that has already 1 Currently, the mission has been operating for more than 7 years already, conducting daily The scientific program of Radioastron mission has three main directions of studies: active One of the mission’s peculiarities is that the space radio telescope has an onboard active hy- More than 40 ground telescopes are participating in the observations. All initial raw data for Very Long Baseline Interferometry technique allow to reach the highest possible angular reso- The ground VLBI is developing rapidly and moving towards the millimeter wavelength range. The senisitivy of ground VLBI is increasing with the introduction of wider bandwidths,However, two by major limitations: atmosphere influence and the finite angular resolution, con- On the 18th of July, 2011 from Baikonur cosmodrome was launched "Spektr-R" – a 10-meter at L-band. Studies of pulsars revealed a new effects of radio emission scattering on the inter- as µ space-ground VLBI observations [ at any time. galactic nuclei (AGN) and quasars,unprecedent masers angular resolution and at pulsars. 3 frequency AGN bands: survey 8 with Radioastron gavestellar the medium. High angular resolutionin of the space-ground scattering interferometer disk resolved [ the substructure Radioastron is operating in aand Moon-perturbed the orbit. apogee varies Orbit from 265000 perigee to varies 360000 from km. 400 The to orbital 65000 period is km, about 9 days. drogen maser frequency standard (H-maser), that givesThe references data for is frequency and received data by sampling. two trackingical stations: Observatory (PRAO) 22-m and radio 43-m telescope antenna of in Pushchino Green Radio Bank Astronom- (NRAO, USA). all observations from space andData ground Processing telescopes Center is [ collected and stored in Astro Space Center (L-band), 4.830 GHz (C-band) andtwo bands 18.392-25.112 simultaneously. GHz Additionally, (K-band) observations and atmode K-band is (MFS) can by capable be switching of done in observing in aMHz range a at for from multi-frequency L-, 18 C-, to and 25 K-band GHz receivers with and 900 16 MHz MHz step. for The P-band. bandwidth is 32 brought numerous number of scientific results [ lution for radioastronomical observations. Targets ofradio interest galaxies, include masers active galactic and nuclei pulsars. (AGN), For example, Event Horizon Telescope (EHT)shadow – [ a global millimeter array to image the black hole improving the coherence time using the watersimultaneous vapor multi-frequency radiometers, observations as [ well as phase transferring with strained by the size of the EarthSuch can approach be solved results also into by launching the oneameter synthesized of providing aperture the the VLBI that microarcsecond elements angular has to resolution space. a unreachable size with much ground larger telescopes. than the Earth2. di- Radioastron Mission space radio telescope – that formed the largest space-ground interferometer Radioastron [ The Current and Future of Ground and Space-VLBI Science 1. Introduction PoS(FRAPWS2018)084 ]. 11 ]. ), Long wave- Rudnitskiy A. G. 12 m µ ]. For the first time the detection for extra 10 ]. 12 2 ), Short-wave Array Camera Spectrometer (SACS, camera: 4 bands: m µ , spectrometer: long slit grating spectrometers: 50 - 450 m µ Currently, ASC Correlator performs processing of about 95% of all the data from Radioastron The next mission that is led by Astro Space Center will be Millimetron. It is going to be a Even though, in autumn 2017, the onboard hydrogen maser has reached the end of itsThere useful a set of scientific tasks to be solved within this observing cycle: multi-frequency po- Prior the launch of Radioastron mission a dedicated Data Processing Center was developed by Data Processing Center can be divided into three parts: 1) online storage of 600 TB for col- ASC Correlator was developed especially for processing the space-ground and ground VLBI mission. By 31.08.2017 3082 outASC of Correlator. 3351 observing sessions of the mission were processed with 3. Millimetron Mission 10-meter deployable cooled space telescope,millimeter observing wavelength at ranges. far infra-red Millimetron(L2) (FIR), will located sub-millimeter be at and operating a in distance themodes: of vicinity as about of a 1.5 single Lagrange million dish point kmmode and 2 are from as the the space-ground three Earth. interferometer. instruments: The Therewavelength expected Millimetron range will payload 60 Heterodyne be - for Instrument 600 two single for operational dish the Far-Infrared (MHIFI, 70, 125, 230, 375 Array Camera Spectrometer (LACS, camera: 4 bands:- 0.4, 3 0.7, mm). 1.2, 2.3 Space-ground mm, VLBI FTSrange is spectrometer: of expected 0.3 1 to - have 17 a mm. set of receivers that will cover the wavelength galactic maser NGC 4258 was found at extreme baseline projections up to 340 000 km [ service lifetime, the mission successfully continuetion its cycle, operation that and started execution in of July, the 2018, next using observa- the closed-loop synchronization modelarization [ imaging of activepulsars, galactic observing nuclei, of water monitoring fountain of sourcesness in the temperature the monitoring scattering Galaxy, continuation with substructure of the the highest for AGN&QSO angular bright bright- resolution. 2.1 Data Processing Center Astro Space Center in order toand meet all processing. the requirements for the Radioastron mission data handling lecting the data anddisks offline and raw backup data copy of storage 2000TB with TB and the on software tapes current correlator for developed volume all byperformance of raw Astro baseband computing 2000 Space data; cluster Center TB 2) of (ASC online on Correlator) 1 datadata. hard to storage Tflops drive operate of for on 80 data high processing; 3) 120 TB storage fordata. processed It has aspace-ground number baselines, of support of features: alltional precise known modes and delay depending widely model on used that the VLBIconvenient handle source data and the class user formats, (processing friendly calculation several graphical of opera- of interface maser, delays [ pulsar for and AGN observations), The Current and Future of Ground and Space-VLBI Science the same effect was observed for the Galactic center [ PoS(FRAPWS2018)084 Rudnitskiy A. G. 3 Aperture of 10-meters for the single dish mode will provide a capability to resolve more than Conception of the scientific program of the mission is to have 5-6 breakthrough scientific tasks For Millimetron a separate Mission Support Center will be organized and it will cover all the Comparing to Radioastron mission Millimetron applies stronger requirements for data pro- Radioastron mission gave a great experience in the development of large space radio tele- This experience made it possible to outline the main critical points of any space-ground VLBI 90% of the sourcesresolution in in the the interferometric mode cosmic will be infrared 100 background times better (CIB). than it At wasto for the be Radioastron solved. mission. same The time, followinggram: problems the are expected to be considered as1) the Determination candidates of for the the nature scientific(Andromeda) of pro- and supermassive M87; bodies located in2) the Search centers of for our wormholeslimetron; Galaxy, M31 in nearby galaxies3) with Measurement of supermassive the CIB central spectrum4) objects distortions; Measurements of using the the interstellar dust Mil- 5) emission Direct contribution observations at of high biomolecules galactic in latitudes; 6) the Search atmospheres for of life transit precursor exoplanets; signs7) in The the origin planetary of and water star inMillimetron formation the project regions; habitable is zones included of in planetary Russiansupport systems; Federal from Space Russian Program state with corporation the "ROSCOSMOS". following Itwill full is be financial expected finished that till Millimetron 2025 spacecraft with the further launch in one-two3.1 years. Millimetron Mission Support Center tasks required for ground support: 1) Collecting and archiving of the2) data; Processing of all thesion’s participants; observational data and organizing3) the Navigational information support exchange of the among mission: mis- orbit simulations, measurements and reconstruction. cessing and collection. The expectedoperation, which volume mostly of come data from the 3300 space-ground PB/year VLBI observations. or 33000 PB for 104. years of Conclusion scopes, organizing and conducting largedelivery scientific and its programs pipeline and processing, as surveys, well settingthe as highest up allowed to angular a get resolution VLBI the in new data the scientific joint results space-ground by providing VLBI observations. mission: 1) Accuracy ofing the of orbit the determination: spacecraft use canaccelerometer of and dramatically laser clock: improve devices ranging the to and be accuracy selectederation selective of according and VLBI to orbit velocity; the track- 3) determination; requirements Choice for 2) of spaceas the On-board craft baseline well accel- vector as projection the to accurate avoid "gaps" scheduling on of the the (u,v)-plane, mission scientific program. It’s possible that successive The Current and Future of Ground and Space-VLBI Science PoS(FRAPWS2018)084 , , , eprint RadioAstron Rudnitskiy A. G. , Astronomy Reports, 57, "RadioAstron" - A telescope Discovery of Substructure in the , Astronomy&Astrophysics, 602, L10, 4 , Solar System Research, 51, 535, 2017. , Monthly Notices of the Royal Astronomical Society, , The Astrophysical Journal, Volume 822, Issue 2, article H2O MegaMasers: a RadioAstron success story Spatially resolved magnetic field structure in the disk of a T , Astrophysical Journal Letters, Volume 794, Issue 1, L14, 2014 Viewing the Shadow of the Black Hole at the Galactic Center , Astronomical Journal, 155, 26, 2018. Radioastron: a radio telescope many times the size of Earth. Research program. The Power of Simultaneous Multi-frequency Observations for mm-VLBI: Beyond PSR B0329+54: substructure in the scatter-broadened image discovered with PSR B0329+54: Statistics of Substructure Discovered within the Scattering Disk on , 514, 597, 2014. 2017. Crutcher, R. M., Li, Zhi-Yun, Rao, R. RadioAstron on baselines up to 330 000 km Kang, S., Kim, D.-W., Kim, J.-Y., Kim,S., J.-S., Wajima, K., Kim, S.-W., Kino, M.,Frequency Miyazaki, Phase A., Transfer Park, J.-H., Trippe, Kardashev, N., Astrophysical Journal Letters, 528, L13-L16, 2000. The inhomogeneous sub-millimeter atmosphere of Betelgeuse Tauri star Five Years After Launch: Main Science Results RadioAstron Baselines of up to 235,000id. km 96, 13 pp., 2016. Volume 465, Issue 1, p.978-985, 2017. Scatter-broadened Image of Sgr A* S., et. al., Moran, J., Sobolev, A., Tolmachev, A., Physics Uspekhi, 52, Issue 11, pp. 1127-1137, 2009. with a size of 300 000Issue km: 3, Main pp. parameters 153-194, and 2013. first observational results arXiv:1801.08796, 2018. Millimetron will be the next step of space based astronomy and will use all the experience [3] Stephens, I. W., Looney, L. W., Kwon, Hughes, W., Fernà A. ˛andez-Løspez,M., M., Mundy, L. G., [4] Zhao, G.-Y., Algaba, J. C., Lee, S. S., Jung, T., Dodson, R., Rioja, M., Byun, D.-Y., Hodgson, J., [1] Falcke, H., Melia, F., Agol, E., [2] Gorman, E. O., Kervella P., Harper G. M., Richards A. M. S., Decin L., Montarges M., McDonald I., [9] Popov, M. V., Bartel, N., Gwinn, C. R., Johnson, M. D., Andrianov, A., Fadeev, E., Joshi, B. C., [5] Kardashev, N. S., [8] Gwinn, C. R., Popov, M. V., Bartel, N., Andrianov, A. S., Johnson, M. D., Joshi, B. C., Kardashev, N. [6] Kardashev, N. S., Khartov, V. V., Abramov, V. V., Avdeev, V. Yu., et al., [7] Kardashev, N. S., Alakoz, A. V., Andrianov, A. S., Artyukhov, M. I., Baan, W., et. al., that was gained duringobservatory the in operation mm, of Radioastron. sub-mmangular and resolution As to FIR a solve it the single most will dish breaking through provide and astrophysical unprecedented space-ground scientific tasks. sensitivity VLBI andReferences the highest [10] Gwinn, C. R., Kovalev, Y. Y., Johnson, M. D., Soglasnov, V. A., The Current and Future of Ground and Space-VLBI Science scientific targets will be rare enough; 4)downlink Provide channel acceptable supply. sensitivity; 5) Provide a consistent data [11] Baan, W., Alakoz, A., An, Tao, Ellingsen, S., Henkel C., Imai, H., Kostenko, V., Litovchenko, I., PoS(FRAPWS2018)084 Rudnitskiy A. G. 5 , Journal of Astronomical Instrumentation, Volume 6, With laser ranging methods, the estimated orbit accuracy Do you have an estimation of the accuracy of orbit determination Issue 3, id. 1750004-131, 2017. Software Correlator for Radioastron Mission could reach dozens of centimeters in position estimation and for the velocity of dozen mm/s. DISCUSSION JIM BEALL QUESTION: required for Space-Ground VLBI? ALEXEY RUDNITSKIY ANSWER: The Current and Future of Ground and Space-VLBI Science [12] Likhachev, S. F., Kostenko, V. I., Girin, I. A., Andrianov, A. S., Rudnitskiy, A. G., Zharov, V. E.,