Space News
space history and artifacts articles

Messages
space history discussion forums

Sightings
worldwide astronaut appearances

Resources
selected space history documents

  collectSPACE: Messages
  Stamps & Covers
  Space Cover 328: Dawn Arrives at Ceres

Post New Topic  Post A Reply
profile | register | preferences | faq | search

next newest topic | next oldest topic
Author Topic:   Space Cover 328: Dawn Arrives at Ceres
yeknom-ecaps
Member

Posts: 660
From: Northville MI USA
Registered: Aug 2005

posted 08-03-2015 08:19 PM     Click Here to See the Profile for yeknom-ecaps   Click Here to Email yeknom-ecaps     Edit/Delete Message   Reply w/Quote
Space Cover of the Week, Week 328, August 2, 2015

Space Cover 328: Dawn Arrives at Ceres

New Horizons' flyby of Pluto received a lot of press coverage — and rightly so — but there was another big event in deep space exploration in 2015: the Dawn spacecraft arrival at Ceres.

Dawn is a deep space probe launched by NASA on September 27, 2007 with the mission of studying two of the three known protoplanets of the asteroid belt, Vesta and Ceres. It is currently in orbit above the dwarf planet Ceres. Dawn is the first spacecraft to orbit two extraterrestrial bodies, the first spacecraft to visit either Vesta or Ceres, and also the first to visit a dwarf planet, arriving at Ceres in March 2015, a few months before New Horizons flew by Pluto in July 2015.

Dawn entered Vesta orbit on July 16, 2011, and completed a 14-month survey mission before leaving for Ceres in late 2012. Dawn entered Ceres orbit on March 6, 2015.

The Dawn spacecraft is propelled by three xenon ion thrusters based on an evolution of the technology used by the Deep Space 1 spacecraft, using only one of them at a time. Dawn was allocated 606 lbs of xenon for its Vesta approach, and carried another 243 lbs to reach Ceres, out of a total capacity of 937 lbs of on-board propellant. With the propellant it carries, Dawn can perform a velocity change of more than 10 km/s over the course of its mission, far more than any previous spacecraft achieved with onboard propellant after separation from its launch rocket. Dawn is NASA's first purely exploratory mission to use ion propulsion engines. The spacecraft also has twelve hydrazine thrusters for attitude control, which were designed to assist in orbital insertion.

Dawn's ion propulsion enabled it to enter and leave the orbit of multiple celestial bodies. Previous multi-target missions using conventional drives, such as the Mariner and Voyager programs, were restricted to flybys.

Dawn is the ninth Discovery mission in NASA’s Science Mission Directorate and is a collaborative partnership made up of the University of California, Los Angeles; Jet Propulsion Laboratory; Orbital Sciences Corporation; Los Alamos National Laboratory; German Aerospace Center; Max Planck Institute for Solar System Research; Italian Space Agency; and Italian National Institute of Astrophysics.

Antoni RIGO
Member

Posts: 176
From: Palma de Mallorca, Is. Baleares - SPAIN
Registered: Aug 2013

posted 08-04-2015 02:43 PM     Click Here to See the Profile for Antoni RIGO   Click Here to Email Antoni RIGO     Edit/Delete Message   Reply w/Quote
Thanks Tom for remembering us that other missions are too protagonists.

With less media attention Dawn arrived to Vesta in 2011 and Ceres in 2015. So the honour of first spacecraft to visit a dwarf planet was not New Horizons but Dawn.

It is especially important for me this multinational mission as very different space agencies are involved.

Frequently collectors do not pay attention to these and most normal are that they do not appear in our space covers.

However, I was lucky to get my cover for Dawn launch from Max Planck Institut für Sonnensystemforschung with the signatures of German Dr. Horst Uwe Keller Framing cameras PI and Spanish engineer Pablo Gutiérrez-Marqués who worked in the development of scientific Dawn camera.

All times are CT (US)

next newest topic | next oldest topic

Administrative Options: Close Topic | Archive/Move | Delete Topic
Post New Topic  Post A Reply
Hop to:

Contact Us | The Source for Space History & Artifacts

Copyright 2020 collectSPACE.com All rights reserved.


Ultimate Bulletin Board 5.47a





advertisement