Green Bank Observer – Vol III, Issue 1

Director’s News

As the calendar year closes and I look back on the year, three exciting new initiatives at Green Bank really catch my attention. LASSI, a new project funded through the NSF MSIP program, will place a terrestrial laser scanner on the GBT to provide near-real time surface corrections. By project completion in 2022, LASSI will allow for high frequency operations during the daytime, and increase the available high frequency hours on the GBT by 1,000. We are also well into the design phase of a new wideband receiver for the GBT. Funded by the Gordon and Betty Moore Foundation, the 0.6 – 2.8 GHz system will double the sensitivity of the GBT for most pulsar timing experiments and will provide wide spectral coverage for other scientific pursuits. Finally, the kick-off meeting for the new First2 STEM Student Success Alliance launched just last week. This alliance, funded by the NSF INCLUDES initiative and led by Green Bank, is comprised of many different organizations across the state of West Virginia and is focused on attracting and retaining rural, first generation students attending West Virginia colleges and universities.

Like much of the astronomy community, the upcoming Astro2020 decadal survey is also much on the minds of the Green Bank staff, and we are working with the community to aid in the writing of scientific papers for the February 19th deadline. Information about Green Bank Observatory’s preparations for Astro2020 can be found at:

Its been another exciting year here in Green Bank, with many great scientific results and educational programs and new projects just getting underway.

I encourage anyone interested in knowing more about our programs and plans to stop by the Green Bank Observatory booth at the AAS meeting, or just drop me an email sometime.

Wishing all of you a happy and science filled new year.

Karen O’Neil
Director, Green bank Observatory


GBT Proposal Call

The 2019B call for GBT proposals is now open, with proposals due Feb 1. Details of instrument availability, proposal types, etc. are in the proposal call.

Results from the 2019A proposal call are now also available. A total of 83 proposals requesting NSF funded open skies time were submitted, requesting 4,472 hours of GBT time. Of these, 32 proposals were approved for observations, with another 11 being approved as “filler” proposals, for an over subscription rate of 2.6. Full details are available here.

Change to proposal Science Categories

Starting with the Call for Proposals for Semester 19B, we will implement a change to the science categories used for the scientific assessment of proposals submitted for the GBT, VLA, and VLBA. The scientific category of Energetic Transients and Pulsars – ETP (encompassing X-ray binaries, cataclysmic variables, supernovae, gamma-ray bursts, pulsars), will be split into two separate categories. This change is being made because the number of ETP proposals has increased substantially over the past few years to the point where it has become impractical to manage through a single panel (even though the number of reviewers on the ETP panel has been increased from 6 to 9). The growing interest in transient radio sources suggests that this issue is likely to continue, and perhaps become more acute in future.

The new science categories will be Gravitational Waves and Energetic Transients – GWT (Supernovae, Gravitational Wave Sources, Gamma-ray Bursts, Tidal Disruption Events, Fast Radio Bursts, Exotic/unknown transients) and Pulsars and Compact Objects – PCO (Millisecond Pulsars, Cataclysmic Variables, Black Hole and/or Neutron Star X-ray Binaries, Pulsar timing, Pulsar proper motion).

For a full listing of the Science Review Categories, visit the NRAO web site.

PIs will need to use these new categories for all proposals submitted after 4 January 2019, including proposals for Semester 19B and any Directors Discretionary Time (DDT) proposals submitted after that date.

Mars Insight Landing

The Green Bank Telecope Observed the Mars Insight Spacecraft landing on Mars on Nov 26.

The most recent spacecraft to land on Mars is “Mars Insight,” which will study the interior of Mars. Insight’s instruments will listen for mars-quakes and measure temperatures below the surface.

The descent through the atmosphere and landing are the critical phases of any landing, and NASA made sure to watch very closely. The spacecraft was followed by two cubesats that could relay signals from Insight to the Earth. Signals were also relayed by Mars orbiters that had been at Mars for several years. The challenging role of the GBT was to receive signals from Insight directly. The GBT is sensitive enough to detect Insight’s signals directly from Mars, although its transmitter is only a few times more powerful that a typical cell phone.

If anything had gone wrong with the cubesats or the orbiters, the GBT was the backup that would receive the information from Insight during the critical landing stages.,Insight had been programmed to go through all the steps needed for landing. The time from when it reached the top of the Martian atmosphere to when it landed was about 7 minutes. With Mars about 90 million miles from the Earth, there was a time delay of about 8 minutes for signals to reach us. Thus there was very little that ground controllers could do if something went wrong.

Two engineers from the Jet Propulsion Laboratory visited Green Bank for the landing. They brought specialized receiving equipment that detected and analyzed the signals from Insight.

During the landing, Green Bank Observatory crew made sure the telescope was pointed correctly and the receiver and electronics were working properly. The JPL crew were in touch with the JPL mission control in Pasadena by telephone and internet. Webcams in the control room relayed the events to the public in the Green Bank Science Center and the Clay Center in Charleston. Sue Ann Heatherly and Rachel Slank provided explanations and commentary for the remote audiences.

The JPL equipment showed the phases of the landing as a “waterfall plot” shown in the illustration. The signal from the spacecraft is the vertical line with time progressing from up to down, and changes in speed are shown as side-to-side deviations. When the spacecraft entered the atmosphere it was protected by a heat shield that heated due to the friction with the air. The hot air was ionized and blocked the radio transmission for a minute — called the “entry plasma blackout” phase. In the free fall phase, the spacecraft was falling a little faster than predicted so the line moved to the right. When the parachute deployed it slowed down and the signal moved back to the left in the diagram. When it landed, the signal became steady at the predicted frequency. The times printed in the illustration are local time (EST).

Waterfall plot showing frequency (x-axis) versus time for the Mars InSight Lander signal. (Source: NSF/AUI/GBO)

The landing events went according to schedule, to the great relief of everyone involved. The confirmation of the landing resulted in applause from the JPL mission control, heard in Green Bank via the telephone line to Pasadena.

Green Bank was involved in previous spacecraft landings: The Huygens lander on Titan in January 2005, and the Mars Phoenix lander in May 2008.

Green Bank Observatory Launches NSF INCLUDES Alliance

Over the past two months, Green Bank Observatory has been assembling policy leaders, college faculty, undergraduate students, and informal educators across West Virginia to collaborate on a massive five year project to significantly improve the graduation rate of students with STEM degrees.

The First 2 Network (F2N), as the project is named, focuses on first generation students and rural students in particular, and their first two years of college, the most vulnerable time when students are most likely to change majors or drop out of school altogether.

F2N had its beginning in 2016 as a pilot project aimed at testing interventions that could increase persistence. The project team gathered findings from the literature and tested 3 high-impact practices, one of which was early immersion in research. Engaging students in a research community early is a strong predictor of persistence, and yet summer programs such as REU are typically offered to Juniors, who, one could argue, have survived their first two years, and will probably be successful.
F2N offered two research internships for rising college freshmen; one at the Observatory, and one at a small university in West Virginia. Twenty seven students participated. Upper level first generation students joined the group to be mentors, and offer counseling on what to expect in college, and how to learn from their own mistakes. External evaluation showed that the internship had a large effect (effect size = 2.56) on students’ motivation to pursue a STEM degree to completion. Four months later, students continued to list the internship as one of the most meaningful experiences of the program.

Another innovative component of the pilot that will be expanded in the Alliance is engagement of first generation college students in leadership positions in all facets of the Alliance. It is only through their own participation that we learn where the failure points are in post-secondary education, and what to do about them. As the Alliance moves forward we will focus on improving high impact practices such as improving college readiness, faculty- student engagement, and early opportunities for research, while we build a solid network that promotes collaboration across institutions and deep learning.

NSF INCLUDES is one of NSF’s 10 big ideas, conceived as a sustained effort to “move the needle” in broadening participation in STEM. The F2N was one of approximately 70 pilot projects and one of five Alliances nationwide to receive NSF funding under this program.

Optimizing Science From Green Bank Telescope Surveys

Since its commissioning, the Green Bank Telescope has been used for a number of surveys that have produced unique data of lasting value. Recent GBT surveys are measuring star-forming molecular clouds in the Gould Belt, searching for new chemical species in Taurus, determining the HI properties of galaxies in the local Universe, determining the distribution of dense gas in galaxies and hot gas in galaxy clusters, searching for H2O megamasers in nuclear disks, and searching for new pulsars toward the north celestial pole.

To explore the ways that the GBO might assist survey science there was a workshop “Optimizing Science from Green Bank Telescope Surveys” held at the Green Bank Observatory on November 13-14, 2018. The goal of the workshop was to develop practical policies for GBO support of survey science, but time was also set aside for survey team meetings, discussion with GBO staff on technical issues, and other activities that might benefit current and future GBT surveys.

Information on the workshop and links to some of the presentations mat be found online.

The workshop produced many valuable suggestions for how the GBO might enhance survey science. Some of these include hosting a survey website, arranging team meetings, training student observers, facilitating the observing, and curating the final data products. We are evaluating these and will implement them as our resources permit. We have already established web sites for several of the surveys and expect to add many more soon.

Many suggestions from this meeting will benefit all GBT observers as well as those conducting large surveys.

Wide Band Feed

The Green Bank Observatory will begin construction of a new ultrawideband radio receiver and digital instrumentation for the Green Bank Telescope. The key science driver for the new instruments is the direct detection and characterization of gravitational waves from the Universe’s most massive black holes, which is the focus of the North American Nanohertz Observatory for Gravitational Waves Physics Frontiers Center (NANOGrav PFC). The NANOGrav PFC looks for the tiny effect of gravitational waves on the arrival time of radio pulses from millisecond pulsars. The ultrawideband receiver will operate at frequencies of about 0.7 to 4 GHz – a “sweet spot” for observing pulsars. This new technology has the potential to double the NANOGrav PFC’s timing precision, making it more sensitive to distant sources of gravitational waves. The ultrawideband instruments will also provide new insight into fast radio bursts and other radio transients.

This project is funded by the Gordon and Betty Moore Foundation.

Recent GBT Publications

On average, a GBT paper* is published every 4.4 days. Review some our most recent list of publications below.

  • Abitbol, M.H. et al. 2018 ApJ, 864, 97. Constraining the Anomalous Microwave Emission Mechanism in the S140 Star Forming Region with Spectroscopic Observations Between 4 and 8 GHz at the Green Bank Telescope
  • Balser, D.S. and Bania, T.M. 2018 AJ, 156:280. Green Bank Telescope Observations of 3He+: HII Regions
  • Kim, J.-Y. et al. 2018 A&A, 616, 188. The limb-brightened jet of M87 down to 7 Schwarzschild radii scale
  • Lam, M.T. 2018 ApJ, 868, 33. Optimizing Pulsar Timing Arrays Observations for Detection and Characterization of Low-Frequency Gravitational Wave Sources
  • Mills, E.A.C. et al. 2018 ApJ, 868, 7. The Dense Gas Fraction in Galactic Center Clouds
  • Swiggum, J.K. & Gentile, P.A. 2018 AJ, 156, 190. On-the-Fly Mapping of New Pulsars

See the complete list of all GBT publications for 2018, as well as past publications, on our web page.

Whenever research using one of the instruments or date from one of the instruments at the Green Bank Observatory is published, we request that the author include a footnote in the paper:

The Green Bank Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.


2019 GBT Remote Observer Training Workshops and Single Dish School

January 22-24, 2019

The Green Bank Telescope (GBT) Remote Observer Training Workshop will provide the essential skills and knowledge needed to use the GBT and maximize its scientific output. It is intended for experienced astronomers who need to learn the specifics of observing with the GBT. After completing the workshop, an attendee will be certified to use the GBT as a remote observer. The workshop will focus on hands-on training in the observing techniques most relevant to participants (e.g. high frequency map, continuum, pulsar, etc.).

The Green Bank Single Dish Training Workshop will provide students, post-docs, and experts in other fields of astronomy with both knowledge and practical experience of the techniques and applications of single-dish radio astronomy using the GBT as the primary example. The school will be based around an intensive series of lectures from experts, as well as hands-on radio-astronomy projects and tutorials. Topics to be covered include radio telescope fundamentals, key single-dish science areas, observing and calibration techniques, the impact of weather, the GBT observing procedures and software, and data reduction.
The cost of lodging and meals will be covered by the observatory, and there is no additional registration fee. Participants must cover the cost of transportation to and from the observatory.

Event Registration

More workshop dates have been scheduled for Aug 19-23 (Single Dish School) and for August 26 & 27 (Remote Observer Training Workshops)

Further information on all training workshops can be found on our web site:

Ira Flatow chosen for the 2019 Frank Drake Lectureship.

March 19, 7:00 PM
Green Bank Science Center Auditorium

The Green Bank Observatory has awarded the 2019 Frank Drake Lectureship to Ira Flatow.

The Frank Drake Lectureship is awarded each year to someone from the sciences, arts or humanities in recognition of their contributions to advancing human knowledge and creativity.

NPR Science Friday Host Ira Flatow.
Source: Science Friday

Veteran science correspondent Ira Flatow is the host and executive producer of public radio’s Science Friday. Each week he brings a lively, informative discussion of science to two million radio and podcast listeners.
Ira is also founder of the Science Friday Initiative, a 501 (c)(3) non-profit organization that is dedicated to increasing the public’s access to science and scientific information.

Ira has shared his enthusiasm with public radio and TV fans for more than 40 years, including as a guest star on the hit CBS comedy, The Big Bang Theory.

His recent honors include the National Science Board Public Service Award, AAAS Journalism Award, the Carl Sagan Award, the Nierenberg Prize for Science in the Public Interest and the Isaac Asimov Science Award. Ira has also received an honorary doctorate from Pennsylvania’s Muhlenberg College.

Dr. Frank Drake, the Lectureship’s namesake, has had a long and distinguished career that began at the Observatory in Green Bank. His scientific achievements include discovery of the radiation belts of Jupiter, and the measurements and characterization of the radio sources at the center of the Milky Way. He also contributed to our understanding of the high surface temperature of Venus. In 1960, using a radio telescope at Green Bank, he made the first modern search for radio signals from extraterrestrial civilizations, He thus began an area of scientific research that has continued and is flourishing today, engaging creative minds worldwide.

Summer Undergraduate Programs

Application Deadline, February 1, 2019

The Green Bank Observatory summer student programs for undergraduate students runs from 10-12 weeks over the summer, from late May to mid-August. At the end of the summer, participants present their research results as a short talk and submit a written report. Financial support is available for students to present their summer research at a meeting of the American Astronomical Society, generally at the winter meeting following their appointment.

Besides their research, students take part in other activities, including a number of social events and excursions, as well as an extensive summer lecture series which covers aspects of radio astronomy and astronomical research. Students, may in their application materials, also indicate a willingness to participate in PING, an opportunity to mentor rising ninth grade students who will be onsite for 2 weeks.

The deadline for applications for 2019 is February 1, 2019. We will accept and review applications in conjunction with the NRAO summer student program again this year. Apply Today!