sci13007 - Announcement

The international Hubble mission

17 October 2013

Dr Charles Mattias ("Matt") Mountain has been the Director of the Space Telescope Science Institute in Baltimore, Maryland, since September 2005. He is also the Telescope Scientist for NASA's James Webb Space Telescope, a member of the Webb Science Working Group, a Visiting Professor at Johns Hopkins University, Baltimore, Md., and a Visiting Professor at the University of Oxford (UK).

Since its inception in the mid-1970s, the Hubble Space Telescope (HST) has always been a joint NASA–ESA mission. So when I was asked to write a few words for the ESA/Hubble Science Newsletter, it created a dissonance in my thinking as I tried to differentiate in my mind what I might say in a European newsletter as opposed to an HST Newsletter. As Director, from my viewpoint, the ESA community has always been very "present" in the way we run and use HST. At the Institute we have ESA scientists who walk the corridors, attend meetings and (at times) argue with the Director indistinguishably from the other science staff at STScI. When we convene User Meetings, Review Committees or our annual Time Allocation Committees, I always find European colleagues fully engaged in all these discussions and debates. In terms of total orbits won, Cycles 20 and 21 were the largest allocations to ESA-led programmes since Cycle 8 (in 1998). For Cycle 20 there were 424 total ESA investigators on accepted proposals, which grew to 482 in Cycle 21. This is substantially more than the roughly 300 in all previous cycles.

So rather than try to rather artificially explore a “European angle”, I thought it would be more interesting to highlight an aspect of HST which I think crosses all national boundaries. What is sometimes overlooked is that, despite being a “Big Science Machine”, HST supports a hugely diverse community of users not just scientifically, or internationally, but also in the scale of programmes that use and exploit HST.

The figure above shows two things. Firstly, the blue histogram shows the number of programmes allocated in Cycle 21 as a function of orbit size: most of HST’s allocated programmes are 35 orbits or less. The red line shows the total number of investigators supported as a function of the size of the programme. Once again the majority of our users are winning time with programmes of less than 35 orbits. At the other end of the scale, we are beginning to see the emergence of larger teams being part of a few really large programmes. The dynamic range in the scale of programmes that HST can undertake is one reason that HST is so productive. Of course another critical ingredient to our unparalleled productivity is the active participation of both the ESA and NASA astronomical communities in the running and scientific exploitation of the Hubble Space Telescope.

Matt Mountain


ESA/STScI Baltimore

About the Announcement



Hubble Exploded View
Hubble Exploded View