TD meaning in Space Science ?

Answer: What is Touchdown mean?

A touchdown (abbreviated as TD) is a scoring play in gridiron football. Whether running, passing, returning a kickoff or punt, or recovering a turnover, a team scores a touchdown by advancing the ball into the opponent's end zone.

reference

Full Form	Category
Tropical Depression	Academic & Science
Table Datum	Academic & Science
Technical Drawing	Academic & Science
Torrential Deposit	Academic & Science
Torrential Downpour	Academic & Science
Tag Database	Academic & Science
Tender Documents	Accounts and Finance
Tabular Data	Accounts and Finance
Toronto-dominion	Banking
Term Deposit	Banking
Turabi Designer	Business
Turn to Delivery	Business
The Toronto-Dominion Bank	Business
Tender Document	Business
Trade Desk	Business
Traslo Device	Business
Technical Diploma	Business
Thinline Double	Business
Toronto Dominion Bank of Ontario	Business
Transorganizational Development	Business
Task Delegation	Business
Transporter Diesel	Business
Technische Dienst	Business
Top Dog	Business
Thermal Diffusion	Chemistry
Thermal Duration	Chemistry
Thermal Desorption	Chemistry
Total Density	Chemistry
Temperature Displacement	Chemistry
Te Deum laudamus (O God we praise Thee) [Lat.]	Community
Thomas Dale	Community
Tape Delay	Community
Talent Development	Community
Tom Demarco	Community
Tony Danza	Community
Thomas Duncombe	Community
Thirumala Devaswom	Community
Thornton-Donovan school	Community
Temporary Document (ITU et al)	Computer and Networking
Table Detail	Computer Assembly Language
Table Definition	Computer Assembly Language
Table Data	Computer Assembly Language
Tannoy Dimension Speakers	Computer Hardware
Tower Defense (video)	Computing
Team Destruction	Computing
Transient Data	Computing
Chad	Country Names
Table Division	Database Management
Table Down	Database Management
Table Delimiter	Database Management
Trinchera Dolina	Earth Science
Time Division	Electronics
Timing Diagram	Electronics
Thermal Donor	Electronics
Turbo Debugger for Dos Configuration File	File Type
Tool Design	General
team Dutch	General
Touring Diesel	General
Tom Drum	General
Thing Description	General
Training Division	General
Tetanus Diphtheria	General
Therapy Dog	General
The Dew	General
Tunnel Diode	General
Territorial Decoration	General
Transverse Defect	General
The Duel	General
Tunnel Drive	General
Tender Design	General
Terrell Davis	General
Tank Driving	General
Taildragger Day	General
tal Digital	General
Tardive Delayed	General
The Dog	General
Tip Drill	General
To Deliver	General
Touchdowns Defense	General
Tower Defence	General
The Decision	General
Tear Drop	General
Turquoise Discharge	General
Triangular Distance	General
True Duane	General
Ticket Dispenser	General
Temporal Discrimination	General
Tag Discover	General
Touchdown Dalton	General
Twisted Destiny	General
Tardive Dyskinesias	General
Transmembrane Distillation	General
Too Dumb	General
Tetanus And Dipteria	General
Teriffic Dolphin	General
Tiny Di	General
Transport Department	Governmental
Tank Destroyer	Governmental
Transit District	Governmental
Target Date	Governmental
Teachta Dála	Governmental
Turbo Diesel	Governmental
Teledyne	Governmental
Transportation Disadvantaged	Governmental
Test Drive	Governmental
Truth Drug	Governmental
Temporary Disability	Governmental
Trust Deed	Governmental
Tanker - Dirty	Governmental
Tracking Dog	Governmental
Total Domination	Governmental
TANDA	Indian Railway Station
Toddler	International
Tres Draughty	International
Trau Dich	International
To die	Internet
Truss Designer	Jobs
Tour Director	Jobs
Tech Dude	Jobs
Technical Director	Jobs
Table Dimension	Maths
Tangent Distance	Maths
Travelers' Diarrhea	Medical
Tetanus & diphtheria Vaccine [adult/adol.]	Medical
Tetanus-Diphtheria Toxoid	Medical
Tetanus & diphtheria Vaccine, adult/adolescent formulation	Medical
Target Dose	Medical
Terminal Duct	Medical
Transmitted Disease	Medical
Tetanus Toxoid without Diphtheria booster	Medical
Texture-Defined	Medical
Total Disability	Medical
Terrier Down	Medical
Toxic Dose	Medical
Tasmanian Devil	Medical
Tardive Dyskinesia	Medical
The Dumper	Messaging
Total Disaster	Messaging
Total Drift	Military and Defence
Totally Dangerous	Military and Defence
Tough Decision	Military and Defence
Training Day	Military and Defence
Targeted Delivery	Military and Defence
Technology Demonstrator	Military and Defence
Training Device	Military and Defence
Technology Demonstration	Military and Defence
Technical Demonstration	Military and Defence
Terrain Data	Military and Defence
Total Distribution	Military and Defence
Transmitter Distributor	Military and Defence
Target Defeat	Military and Defence
Temporary Duty	Military and Defence
Training Development	Military and Defence
Tower Defense	Military and Defence
Theater Distribution	Military and Defence
Tie Down	Military and Defence
Timing Distributor	Military and Defence
Traffic Director	Networking
Temporal Difference	Physics Related
Time Definite	Physics Related
Time Differential	Physics Related
Trojan Downloader	Softwares
Technical Directive	Space Science
Terminal Distributor	Space Science
Test Director	Space Science
Time Delay	Space Science
Touchdown	Space Science
Transmit Data	Telecommunication