Going from worst to first
In April of 1990 I was offered a job at the Space Telescope Science Institute to work on a NASA mission that would be launching just two weeks later: the Hubble Space Telescope. I was elated to be at the Kennedy Space Center to watch the Space Shuttle Discovery launch Hubble and my career along with it.
But by the summer of 1990, elation had turned into horror as Hubble was revealed to have flawed optics. At that low point, it was impossible to imagine the Hubble of 2020: a soaring icon of modern science which has inspired people all over the world. Instead, Hubble was being vilified in the news (below) and by late-night comedians. We pessimistically wondered how long the mission would last — just 18 months, according to an informal hallway poll! But the Institute was also optimistically leading the brainstorming for a Hubble fix, and the dramatic turnaround is now legendary in the history of science.
The worst-to-first story of Hubble’s heroic restoration has been told many times before, and now 30 years later the Hubble brand is unassailable. For those of us who were working on Hubble in the gloomy era of the early 1990s, each anniversary is particularly sweet because we are so keenly aware of how close we came to a legacy more like that of the Titanic. Hitting the 30-year mark on a planned 15-year mission, you have to wonder if this will be the last big anniversary. However, Hubble is going strong in 2020 and we have good reason to think it will continue for many more years.
Bringing the world along for the ride
I brought this history and mindset with me through every step in the process of working with the rest of the outreach imaging team to design, propose, and execute the Hubble observations that would become the 30th anniversary image. One of the most fulfilling aspects of my job has been contributing to “outreach imaging” — Hubble observations that are primarily art projects, designed to inspire and bring everyone along for the ride. They only become science projects for archival researchers who access the high-level data sets that we create and share. In outreach imaging we use all of the best practices for observing strategy and data processing as if it were a science project, so none of Hubble’s “pretty pictures” are a waste of precious observing time. In fact, we are quite proud of all the scientific publications that result from our outreach observing programs.
But our primary criteria are shamelessly aesthetic. We always have a running wish list of beautiful targets, with rough ideas of how much they would cost. The biggest targets, requiring multiple pointings in a mosaic pointing pattern, are reserved for anniversaries when we can usually get the large number of Hubble orbits required to conduct the observations.
A few years ago, and somewhat on a whim, our former team leader Zolt Levay wondered about going after a target that had some numerical connection to Hubble’s 30th anniversary in 2020 — hmm, what does NGC 2020 look like? Many objects in the New General Catalog (NGC) are not particularly impressive. So Zolt was delighted to find that NGC 2020 was actually quite striking, and possibly worthy of being a Hubble anniversary image. Zolt retired in 2018, but NGC 2020 stayed on our shortlist with some other worthy candidates, and in discussions during the summer of 2019 it bubbled to the top. The numeracy of “2020” was not actually the primary factor in the decision. Everyone was enamored with the strong color contrast between the bluish ionized oxygen of NGC 2020 and the reddish hydrogen gas of nearby NGC 2014 seen in an earlier image from the Very Large Telescope. The crowded and colorful star field, and several smaller nebular features, added even more to feast your eyes on. We felt we could make a bigger and uniquely Hubble-quality image of this region of the Large Magellanic Cloud.
We initially planned to use both of Hubble’s cameras in tandem, with the adjacent “parallel” image — which added more of the nebulosity around NGC 2014 — simply being a bonus for archival researchers. We weren’t thinking it would be a part of the anniversary image because the image quality would be noticeably different between the two cameras. But as you can see in the slideshow below, that nebulosity is interesting in itself, with an aquatic “brain coral” appearance. So we decided the get it all with one camera, the Wide Field Camera 3 (WFC3) which was installed by astronauts in 2009. I designed a large mosaic (with pointings in a 4 × 3 pattern) which stretched to get the entire region with uniform data quality and color filters. The following slideshow illustrates what a Hubble mosaic pointing pattern looks like, how our observation planning evolved over the last nine months, and the resulting color composite image.
This is a complex target with very faint wispy nebulosity that we wanted to detect — but also with very bright stars interspersed, which threatened to saturate and “bleed” all over the nebula if our exposure times were too long. So there was much debate and strategizing over the pointings, filters, and exposure times — and then some nervousness as we waited for the data to arrive. On New Year’s Eve our observing program started right on cue. We had Hubble observing NGC 2020 as the calendar flipped into 2020, its 30th year in orbit.
It was challenging work over the last nine months for our team to get a proposal approved by our Director, get this big mosaic scheduled, repeat a few failed observations, stitch together 12 pointings into monolithic images for each of 4 filters, prepare a color composite image for the press release, and deliver our specially prepared data to the archive. But it was truly a labor of love, and it is astonishing that Hubble can still deliver the wow-factor in 2020. Every pixel is the result of countless talented and dedicated people who have made this mission a success over the decades: engineers, scientists, astronauts, leaders, educators, artists, and the worldwide public.
Science in the time of Coronavirus
Like so many other iconic Hubble images over the last 30 years, we hope this new one inspires people, and reminds everyone why we do science: to gain a deeper understanding of nature, our origins, and our fate. When we started this project, we didn’t know the year 2020 was going to be so bleak here on Earth and that we would be celebrating Hubble’s 30th anniversary while distanced from each other. But in this dark moment, it has perhaps never been clearer that science also provides hope for humanity, and is essential for managing our future.
This blog post is one in a series marking the 30th anniversary of the launch of the Hubble Space Telescope. For more information and resources regarding Hubble’s 30th anniversary, please visit Hubblesite.
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