Shanghai VLBI Center Activities Zhong CHEN On behalf

Shanghai VLBI Center Activities Zhong CHEN On behalf of VLBI Center team Shanghai Astronomy Observatory, CAS IVTW 2018 • Krabi, Thailand • 12 -15, Nov. 2018

Outline 1. Overview of CVN 2. VLBI Center Activities • CLEP Projects • Correlator and e-VLBI Operations 3. Future Works

CVN VLBI Network • Stations • • • Sh – Shanghai Sheshan, 25 m, 1987 Ur – Xinjiang Urumuqi, 25 m, 1993 26 m, 2016 Bj – Beijing Miyun, 50 m, 2006 Km – Yunnan Kunming, 40 m, 2006 T 6 – Shanghai Tianma, 65 m, 2013 VGOS – Shanghai Tianma Park, 13. 2 m, 2018 • VLBI Data Center • VLBI tracking system for China’s Lunar Exploration Project (CLEP) • Since 2007 (Xuhui HQ), 2012 (Sheshan Park) • IVS Correlator, 2012 3

CVN L, S/X, C(6 cm), K S/X QTT VGOS FAST S/X, C T 6 L, S/X, C, X/Ka, K, Q Sh L, S/X, C(6 cm) Data Center

CVN Live Cam Ur, XAO Sh, SHAO Bj, NAOC VLBI C&C Hall T 6, SHAO Km, NAOC VGOS, SHAO

VLBI for Deep Space missons • VLBI Tracking and Measurement System for CLEP − − Phase I: CE-1 y 2007 Phase II: CE-2 y 2010 , CE-3 y 2013 Phase III: CE-5 T 1 y 2015, CE-5 y 2019 Phase IV: CE-4 & DRS y 2018 , CE-7, CE-6, CE-8 • Mars exploration − 2020 -2023 − Orbiter, Lander, Rover • Asteroid exploration − 2022 -2032 • Need New Antennas 6

Chang. E Probe Flight Orbit CE-1 CE-3 CE-2 CE-5 T 1

CE-4 DRS & Probe CE-4 Data Relay Satellite

CE-4 DRS • Tracking Periods – Critical, Important, Long-Term-Operation – e-VLBI, Auto e-Transfer s 8601 a s 8706 a s 8602 a s 8706 b s 8603 a s 8707 a s 8521 a s 8604 a s 8710 a s 8806 a s 8522 a s 8605 a s 8711 a s 8807 a s 8523 a s 8606 a s 8712 a s 8809 a s 8 a 04 a s 8524 a s 8607 a s 8712 b s 8811 a s 8 a 06 a s 8525 a s 8608 a s 8718 a s 8813 a s 8 a 15 a s 8526 a s 8609 a s 8721 a s 8814 a s 8904 a s 8 a 16 a s 8527 a s 8610 a s 8723 a s 8818 a s 8905 a s 8 a 17 a s 8528 a s 8611 a s 8620 a s 8723 b s 8820 a s 8912 a s 8 a 18 a s 8529 a s 8612 a s 8621 a s 8723 c s 8824 a s 8914 a s 8 a 19 a s 8530 a s 8613 a s 8621 b s 8729 a s 8828 a s 8921 a s 8 a 21 a s 8531 a s 8614 a s 8626 a s 8730 a s 8829 a s 8925 a s 8 a 22 a May June July Aug. Sep. Oct.

VLBI Center for CLEP • Command & Control Center • Real-time Tracking & Data Transfer & Processing

Dedicated Network and e-VLBI

CLEP VLBI Accuracy • CE-3 • X band DOR Signal • Earth-Moon transfer orbit phase & Circumlunar segment − − ΔDOR tracking group delay < 4 ns (Actuality <0. 5 ns) 100× 100 km circumlunar orbit accuracy: 20 m 100× 15 km circumlunar orbit : 30 m Descent trajectory: < 100 m • Lunar surface working phase − Lander & Rover tracking by SBI − Lander 3 D position <1 km (Actuality <100 m ) − Rover relative position of the lander <500 m (Actuality ~1 m ) • CE-4 DRS • S band, orbit accuracy: ~1 km

Correlator Cluster • Total: 70 TFlops, 3. 2 PB • 2 Active/Standby Management nodes • 8 GPFS Storage Nodes • 48 Correlator Nodes + 7 Fringe Searching GPU Nodes • 20 Old Nodes for Dev and Testing • 2 Archive Data Nodes

IVS and VGOS correlator • IVS Correlator − Di. FX 2. 5 400 CPU Cores(E 5 -2660) 437 TB Storage, Bee. GFS Shared: 1 Gb. E, 56 Gb IB Network − CVN SCorr 128 Cores (X 5550) 182 TB Storage − Intl. e-Transfer server: 2 Rack Servers • Mark 5 Upgraded to 64 bit − Sh, T 6, Ur, Km − Center: 2 Mark 5 A, 4 Mark 5 B/B+ • CScorr Upgraded − 8 Compute Servers • Gold 6132, 2. 60 GHz, 96 GB DDR 4 Mem − 1 Storage Server: 720 TB, 90 disk/chassis Di. FX New Servers CScorr New Storage

Observations • Sessions − − − − IVS: routinely EVN: Ef+T 6 VLBA CVN AOV CVN+Quasar EAVN CE-4 DRS CE-4 Ecliptic Plane Survey: VEPS-1 Prof. Shu Fengchun

Internet e-VLBI • Connected and supported by CSTNET(Chinese Science & Technology Network, CAS)

e-VLBI Connected Stations – SHAO’s Tianma & Seshan – VLBI Center – IVS stations and correlators e-Transfers – – IVS EVN e-VLBI EAVN Pre-SKA Researches 2 nd Australia-China SKA Big Data WS, May, 2018 NGAS Data Transfer Multiple TCP streams

CLEP VLBI Database Supported by Fundamental Science Data Sharing Platform, MOST https: //www. vlbi. nsdc. cn Dataset – CLEP VLBI tracking data: CE-1, CE-2, CE-3, CE-5 T 1 – Will add following missions datasets – Online Search, offline download – EN version still under develping

Future Works • Shanghai VLBI center − − Built for CLEP missions Long-term deep spaces missions More sessions work of Geodetic, Astrometry, Astrophysics Preparatory works for VGOS

Our Team

Thanks！