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CAMSAT released information on the CAS-7B satellite, due to launch this month:

On January 18, 2019, NEXUS was launched on an Epsilon launch vehicle from the JAXA Uchinoura Space Center in Japan. NEXUS (NExt generation X Unique Satellite) is a satellite developed jointly by Nihon University College of Science and Technology and the Japan Amateur Satellite Association (JAMSAT).

NEXUS demonstrates several new amateur satellite communication technologies, and includes a mode V/u linear transponder.  Telemetry has been received and decoded around the world since the launch, and the transponder was successfully tested on January 26th. More information may be found at http://sat.aero.cst.nihon-u.ac.jp/nexus/E0_Top.html

At the request of the Nihon University College of Science and Technology and JAMSAT, AMSAT hereby designates NEXUS as Fuji-OSCAR 99 (FO-99). We congratulate the owners and operators of FO-99, thank them for their contribution to the amateur satellite community, and wish them continued success on this and future projects.

On January 18, 2019, OrigamiSat-1 was launched on an Epsilon launch vehicle from the JAXA Uchinoura Space Center in Japan. The first satellite of the ORIGAMI (ORganizatIon of research Group on Advanced deployable Membrane structures for Innovative space science) Project of the Tokyo Institute of Technology, OrigamiSat-1 includes a deployable membrane structure experiment, as well as a 5.8GHz high speed downlink experiment. Telemetry has been received and decoded around the world since the launch. More information may be found at http://www.origami.titech.ac.jp/

At the request of the Tokyo Institute of Technology, AMSAT hereby designates OrigamiSat-1 as Fuji-OSCAR 98 (FO-98). We congratulate the owners and operators of FO-98, thank them for their contribution to the amateur satellite community, and wish them continued success on this and future projects.

Every time a CubeSat gets launched, there is some confusion on what TLEs should be used.   This is the result of the process of launching a new amateur CubeSat with other CubeSats, often several dozen at a time.  We then start the  process of determining which object in a “flock” of CubeSats  is associated with a particular spacecraft.

Pre-launch TLEs that are calculated based on the expected orbit are usually supplied by the launch provider. Pre-launch TLEs are used until post-launch TLEs (for the group of objects that your satellite is in) are released from the US Department of Defense Joint Space Operations Center (JSpOC) based on observations made with cameras and radars.

There is a a 5 to 10 day period of tracking a group of CubeSats until they separate enough to isolate the one of interest. By observing the Doppler shift on transmissions from a particular satellite against the calculated Doppler shift from all candidate object TLEs, we can positively associate an object with a particular satellite. In the case of AMSAT satellites, we then advise JSpOC which object number is “ours”.

Finally, an individual satellite and its associated TLEs are determined and we settle down to an single, accurate, reliable set of TLEs … and all the other “best guesses” go away, although they may be still floating around on the Internet. But, there are so many variables  – did you launch on time, did you get released on time, has the group your CubeSat is in separated enough to identify your satellite, etc. that the process that can be both confusing and annoying at the same time.

AMSAT strives to minimize confusion when distributing TLEs.  Dummy object numbers are used for pre-launch TLEs since final object numbers cannot be assigned yet.    Immediately post launch we may post candidate objects with generic names like “OBJECT C”.    Finally, when positive association between an object number and a spacecraft is made, we will use the common name of the satellite.   We always recommend using TLEs from the Keps mailing list or the current bulletin or bare elements from the AMSAT web site.

by Ray Hoad
WA5QGD
Orbital Elements Manager