markf%Nosc@usiiden.ARPA (07/31/85)
From: <crash!usiiden!markf@Nosc> Science News Conference - Spacelab 2 Tuesday 7/30 *Ron Lester: I'll start by giving you a brief status of theSpacelab systems. I'll talk briefly about each of theexperiments. I'll also discuss the mission planning thatwe're doing for perhaps some addition al time on the PDP(Note: Ejectable Plasma Diagnostic Package usesinstruments on a subsatellite to study plasma processes).The Spacelab systems were activated pretty much on time.The backup computer, which is now serving as the experimentcomputer came up o n schedule and its been performingflawlessly. We've had two drop offs of the DDU's (note:don't know what this is), we had a similar situation onSpacelab 3. The instrument pointing system, we've got itup, we have had difficulty with the optical sensingpacka ge - turning the package onto the Sun in the fineguided mode (note: The SOUP or Solar Magnetic And VelocityField Measurement System will observe the strength,structure, and evolution of magnetic fields in the solaratmosphere and determine the relationshi p between thesemagnetic elements and other solar features). I'll tell youlater about some of the trouble shooting activitiesassociated with that. We are convinced by the fact that theCoronal Helium Experiments (Note: CHASE, the coronal heliumabundance spac elab exp will accurately determine the heliumabundance of the Sun) was able to, operating within thecontrol loop of the IPS (instrument pointing system) was infact able to acquire the Sun, and in fact, he's got data,and as a matter of fact, tommorrow morn i ng will get some ofthe data that they have already obtained. With respect tothe physics experiment, the optical polarimeter (Note:SOUP), we do have a problem with the pilot system. The guysare still trouble shooting it, both here (Houston) andback at Lock heed. But currently, it is not operating, itdid come up and operate for some 15 minutes, but it droppedoff line and to date we have not been successful withtrouble shooting approaches. But the guys are working onit, the IPS is not due back up until one da y 14. TheCoronal Helium Exp. has been taking data, even from thedegraded mode of the instruments on the system. The HighResolution Telescope (Note: HRTS Solar Ultraviolet HighResolution Telescope studies features in the Sun's outerlayers; the chromosphere, the corona, and the transitionzone between them) has yet to start taking data, it hascompleted its checkout. He did have a heater fail on it, hedeactivated the system, we really don't anticipate thatca using a problem once we get operational. He will be uptommorrow when we reactivate the IPS and we fully expectthat he will operate. I'll discuss later some of theconsequences of not being able to get the optical sensingpackage up and operating. We feel we can still obtain thescience on the solar experiment by the use of the HRTSexperiment. The ITS (?) is stowed now, so obviously has notbeen taking data now. PDP (Plasma Diagnosics Package) hasbeen activated, it continually takes data .. we did firethe elec t ron generator (Note: the PDP can be placed nearvehicle surfaces to measure changes in the Shuttle'selectrical charge as a generator emits an electron beam)and the plasma diagnostic people did pick up the results.On the Plasma Depletion Experiment (Note: t hisinvestigation uses the Shuttle as an active experimentalprobe to create artificial "holes" in the ionosphere.Ground observatories use radio and optics to study theplasma characteristics and conduct radio astronomicalstudies through them) we've had two s uccessful burns, oneover Milstone, the other over Areceibo in Puerto Rico. Weoriginally had some seven burns or so scheduled. Based onsome very recent data we've got, it looks like we may beable to re-instate some of those burns. The cosmic rayexperiment (Note: CRNE Elemental Compositon and EnergySpectra of Cosmic Ray Nuclei Between 50 GeV/ nucleon andseveral TeV/ nucleon - to study the composition of highenergy cosmic rays by using a large instrument exposed tospace for a considerable period of time) sta r ted takingdata almost immediately and has continued to take data. Itoperates in somewhat of a passive mode. The X-Ray telescope(Note: XRT Hard X-Ray Imaging of Clusters of Galaxies andOther Extended X-Ray Sources - the goal of thisinvestigation is to imag e and examine the X-ray emissionsfrom clusters of galaxies in order to study the mechanismsthat cause high temperature emissions and to determine theweight of galactic clusters) is up and running. And I guesshe's quite happy, for the next 16 hrs. he can o p eratewithout the place and avoidance (?) being invoked which isprotection between the X-Ray telescope and InstrumentPointing System when they operate simultaneously. But sinceIPS is in the gimbal lock, he is unrestricted and will betaking data for the nex t 16 hrs. The X-Ray telescopechecked their drive systems. The Helium experiment (Note:Properties of Superfluid Helium in Zero Gravity - todetermine the fluid and thermal properties of superfluidhelium, to advance scientific understanding of superfluidand normal liquid helium, and to demonstrate the use ofsuperfluid helium as a cryogen in zero gravity). That's theexperiment that just prior to launch on July 4th, we had tomake a decision to de-activate a pump, it started leakingoil in the cargo bay, we would have probably lost theexperiment had we launched on the 12th. So that's a plusfor the delay. The Plant Growth Unit (PGU - to determinethe effect of microgravity upon the production of lignin inhigher p lants) which is in the middeck, it pretty much doesits own thing. The crew periodically monitors temperaturesand some other measurements. The vitamin B experiment andcrystal growth experiment are on-going. That's pretty muchthe status of the experiments. With the exception of thepolarimeter experiment, the team is elated with how thingsare going. * We have also been told that we have some 1400lbs of propellant (more than we thought) and this makes asignificant differences as to what we can do. Variousopti o ns are being looked at, at this time. Most like use isfor one of the three originally planned fly arounds withthe PDP. This will make two fly arounds. Raising thealtitude is unlikely since the amount of surplus fuel wouldbe unlikely to contribute to the s cience being obtained.The experiment most effected by the altitude is the coronalhelium experiment. But he has obtained some very good dataat the altitude he's working at. Obviously, we're lookingat a full duration mission.