Speaking of Hubble...

Archive: July 2011

Astronomers Thinking of the Future

July 27, 2011 by Jason Kalirai

JWSTfontiers_200x170As an astronomer, one of the truly rewarding parts of my job is to share new scientific discoveries with other astronomers. We typically do this at meetings where we give short, 15-20 minute presentations on our recent research. I usually find these meetings to be very valuable, since I can form new collaborations and get involved in cutting-edge research projects.

Recently, I found myself in a different role, as the chief scientific and local organizer for one such meeting, a major international conference. The meeting brought together almost 200 astronomers from across the world to share in “Frontier Science Opportunities with the James Webb Space Telescope.”

The process of organizing a big meeting such as this begins more than nine months before the actual meeting. Late last year, we formed a “Scientific Organizing Committee” (SOC) consisting of a dozen members of the astronomical community, including myself.

We decided that we would like to jump-start a discussion of high impact science programs that the James Webb Space Telescope (JWST) could perform when it launches later this decade. The goal is to get astronomers actively thinking about the telescope, so we can jump into the science quickly when it’s ready.

Next, the SOC selected about a dozen speakers and invited them to the meeting to share the diverse research topics that Webb could address. With this list of experts posted, we opened up registration in January 2011. The community responded with a flood of interest. We received dozens of requests for contributed talks and presentations. Over the past few months, I have been involved in scheduling the meeting, organizing the discussion sessions, and planning a dinner for our guests at the Maryland Science Center with a screening of the “Hubble 3D” IMAX movie.

The payoff for all of the work came when the first science talk began. The topic was how Webb could improve our understanding of the atmospheric structure of nearby planets, such as Uranus and Neptune. The next talk told us how Webb could enable discovery of the first stars that exploded in the universe, through imaging of “Pair Instability Supernovae.” We were off to a good start! With the first two talks, we had covered a range extending from the nearest objects in the universe to some of the farthest away.

The conference continued for three full days and paved the way for a very exciting Webb science case that touches on many different topics: studying extrasolar planets and their atmospheres; learning how galaxies come together by mapping the ages, motions, and chemical nature of their stars; and discovering the first galaxies that emerged when the universe was in its infancy. Although some of these science goals are similar to those defined for Webb years ago, the presentations at the meeting provided a rejuvenated interest in these endeavors. In fact, many of the science cases have become stronger in light of recent research in these fields.

We discussed the criteria astronomers would use for future discoveries with Webb. If we find a planet with water vapor in its atmosphere, what kind of other criteria would be needed to declare that planet potentially life-bearing? When we’re looking at the most distant stars in space, what litmus tests must they pass before we can determine that we’re looking at the universe’s very first stars?

“Frontier Science Opportunities with JWST” also revealed that astronomers have a lot of homework to do before the telescope launches into space. Participants emphasized the fact that we have precious resources in astronomy right now that could be used to observe the types of exotic objects Webb will study. We could make those observations now and have a wealth of additional data for astronomers to study in conjunction with the eventual Webb observations – just as space telescopes like Chandra and Spitzer have been used to provide complementary observations for Hubble. One of my goals for the next few years will be to investigate this further and come up with a plan to ensure that we fully capitalize on our existing missions to make Webb that much more successful.

Want to know more? All of the talks and Powerpoint slides for “Frontier Science Opportunities with JWST” are posted at http://webcast.stsci.edu/webcast/.

Thank You Very Much for the Ride

July 21, 2011 by Frank Summers
The landing of space shuttle Atlantis at 5:57 a.m. EDT, July 21, 2011 marks the end of the Shuttle Program.

Space shuttle Atlantis touches down at 5:57 a.m. EDT, July 21, 2011.

NASA, along with all space enthusiasts, is celebrating the end of an era this month. Atlantis’ visit to the International Space Station (STS-135) marks the last mission of the space shuttle program. Thirty years of astronaut flights to low-Earth orbit on the Space Transportation System (STS) have now come to a close.

While human spaceflight and scientific research are generally considered separate pieces of NASA’s mission, here at Hubble they have been inextricably intertwined. Hubble was taken to orbit aboard Discovery (STS-31) on April 24, 1990. The very design of Hubble had to accommodate fitting into the payload bay of the shuttle. Hubble was also designed to be serviced by shuttle astronauts, a feature that has been crucial to Hubble’s success and longevity.

In 1993, the first servicing mission (STS-61) installed corrections for a flaw in Hubble’s main mirror, enabling Hubble to achieve all of its original science goals. Further missions brought Hubble new scientific instruments, increasing and expanding its capabilities, in 1997 (STS-82), 2002 (STS-109), and 2009 (STS-125). Telescope maintenance, performed on all servicing missions, was the sole focus of STS-103 in 1999, when Hubble suffered gyroscope failures. Shuttle astronauts even accomplished several long and delicate repairs of science instruments that were never designed to be serviced.

The success of the Hubble Space Telescope is both a stellar achievement of scientific discovery and a resounding triumph of NASA’s space shuttle program. We at the Space Telescope Science Institute are grateful to everyone who has worked on the servicing missions and anyone who has worked on the shuttle program. Hubble’s amazing views of the universe are part of your legacy.

The one sad note is that the end of shuttle flights also means the end of Hubble servicing missions. Designed for the specialized hardware of the space shuttle, repair missions by another vehicle are untenable at best. But thanks to the last shuttle servicing mission, Hubble looks to have a bright future for the rest of this decade, and maybe beyond.

Hubble’s fate has always been tied to the space shuttle. Looking back, it has been an incredible journey. The words spoken to shuttle astronauts as Hubble was released into space 21 years ago seem ever so appropriate now: “Thank you very much for the ride.”

Wonder and Amazement — The Role of the James Webb Space Telescope

July 13, 2011 by Mario Livio
Artist's depiction of the Webb telescope

Artist's depiction of the Webb telescope

An entire generation has been inspired and informed by the discoveries and spectacular images produced by the Hubble Space Telescope. The”Pillars of Creation,” the “Hubble Ultra Deep Field,” and the “Mystic Mountain” images have not only given us an entirely new perspective on the place of humans in the cosmos, they have rivaled the best art works of our time for visual impact. The James Webb Space Telescope promises to be the “Hubble” for the second half of the present decade and beyond.

One cannot overestimate the importance of inspiration. An old Chinese tale describes a starving man who has found a coin. For half the value of that coin he buys bread – to live – and for the other half he buys a flower – to have something to live for!

Last week, PBS aired a remarkable story that was nothing short of a modern manifestation of this tale.  It described how in the midst of unimaginable horror in the Democratic Republic of Congo, a miraculous symphony orchestra continues to play classical music in Congo’s capital, Kinshasa. You might have thought that the hardships of everyday life would extinguish all art forms, defining them as useless. Yet, this orchestra apparently gives many Congolese something to live for.

Similar sentiments apply to science.

Albert Einstein remarked once that: “The fairest thing we can experience is the mysterious. It is the fundamental emotion which stands at the cradle of true art and science. He who knows it not and can no longer wonder, no longer feel amazement, is as good as dead, a snuffed-out candle.”

What is true for individual men and women is also true for entire nations.  I believe that the James Webb Space Telescope will play an essential part in our future collective experience of the mysterious.

Thanks a Million, Hubble Fans!

July 11, 2011 by Frank Summers
Artist's concept of the extrasolar planet HAT-P-7b. On Monday, July 4, Hubble logged its one millionth science observation during a search for water in this exoplanet's atmosphere 1,000 light-years away.

Artist's concept of the extrasolar planet HAT-P-7b observed by Hubble on July 4. The observation marks Hubble's one millionth science observation.

Launched in 1990, the Hubble Space Telescope has had a long and distinguished mission of scientific discovery. We have celebrated five successful servicing missions, 21 years in space, and over 100,000 orbits around Earth. As the most productive of NASA’s space observatories, Hubble is still going strong and we hope to pass many more milestones.

One such numerical achievement was announced this week: the one millionth observation. Hubble has looked at the sky and recorded data a million times. That’s a lot of skywatching and a good excuse for some festivity.

Two questions naturally arise. One, which picture was the one millionth observation? Two, where I can see all one million pictures?

First, not all Hubble observations are images. Although the public sees mostly images in press releases, Hubble science is also done by taking spectra. To do science, the telescope’s spectrograph instruments spread out light from an object into its component wavelengths, and measures the intensity at each wavelength. The simplest example of a spectrum is a rainbow, which occurs when the Sun’s light is spread into its component colors.

Hubble’s one millionth observation, as it turns out, is a spectroscopic measurement intended to search for water vapor in the atmosphere of a planet 1,000 light years away from Earth.

Second, you won’t find one million images and spectra here on HubbleSite. Our press releases feature perhaps 100 pictures a year, making about 2,000 images available. Some of our images include spectra diagrams, but the spectra data formats, although publicly available, are not what you call “public-friendly.” Where are the rest? They can be found on the Multi-Mission Archive at Space Telescope, or MAST. MAST is the Hubble data archive that professional astronomers use when they do their research. As such, it is both publicly accessible (Hubble observations are available to all) and “expert-friendly” (designed for astrophysicists). The MAST data archive contains all the images, spectra, and calibrations ever taken by Hubble. This trove of data is Hubble’s scientific legacy, and will be useful for generations after the observatory has finished operations.

Hitting the million-observation mark makes me want to look back and forward: back to the long history of challenges and successes, and forward to new research yet to unfold. One thing is certain; all the folks who have continually voiced their support for Hubble and astronomical discovery have been a big asset in achieving this milestone. What else can we say but “Thanks a million!”