New deadline for JWST Cycle 1 General Observer proposals

The JWST Cycle 1 General Observer (GO) proposal deadline will be 08:00 pm Eastern Time (ET) on Tuesday November 24, 2020.

The major disruption caused by the COVID-19 pandemic continues to affect all of us.  Integration and testing of the James Webb Space Telescope are among the activities impacted. NASA has re-evaluated the project schedule and announced a launch readiness date of October 31, 2021.

After consulting with the JWST Users Committee, STScI, NASA, ESA and CSA have finalized the review schedule for Cycle 1 proposals. 

We are announcing the deadline well in advance, so that proposers have flexibility to prepare proposals as their COVID-impacted schedules permit.  



The CALL FOR PROPOSALS remains unchanged from its release earlier this year. 

All proposal tools and DOCUMENTATION are available to proposers.


The JWST Telescope Allocation Committee (TAC) will review the proposals in February 2021 and recommend the Cycle 1 GO science program for announcement in March 2021.

We send best wishes to our user community and their families in these challenging times.

As always, please contact the MIRI French Centre of Expertise if you have any questions.


As always, please contact the MIRI French Centre of Expertise if you have any questions.


From the Space Telescope Science Institute: Cycle 1 GO/AR

The novel coronavirus COVID-19 has changed almost every aspect of our lives. Significant uncertainties persist with regard to how the situation will evolve over the summer and fall.

Under those circumstances, and after consulting with the JWST Users Committee, STScI, NASA, ESA and CSA have decided to delay announcing a formal schedule for JWST Cycle 1 GO/AR proposals. We anticipate providing a further update on the schedule in mid- to late-July. 


For planning purposes, STScI is exploring options for a proposal deadline in the fall with the Telescope Allocation Committee meeting in early 2021. The JWST launch schedule is evaluated independently by NASA. 


Recognising the challenges faced by the community, we will give at least twelve (12) weeks notice of the revised Cycle 1 proposal deadline. The JWST Call remains open and all proposal preparation tools and documentation continue to be available.


These remain stressful times for all of us. We wish the best to all members of our community and their families, particularly those affected directly by the pandemic.

As always, please contact the jwst helpdesk if you have any questions.

The Cycle 1 Deadline for the Proposals Has Been Delayed

Release from STScI (March 19, 2020):

The novel coronavirus COVID-19 is causing significant impact and disruption on the worldwide community. The situation is evolving rapidly with no obvious conclusion in sight.

Given those circumstances, STScI, NASA, ESA, and CSA have taken the decision to delay the proposal deadline for JWST Cycle 1 General Observer (GO) proposals to no earlier than May 27, 2020. We are continuing to monitor the situation, and will provide an update on the schedule on April 15, 2020.

Given the delay in the #JWST Cycle 1 proposal deadline, GTO and ERS teams now have additional time – until April 27 (instead of March 31) – to submit final revisions of their programs.

These are stressful and challenging times. Our thoughts go out to all those affected by the current situation.

Release of the new version of the APT

The Astronomer’s Proposal Tool (APT) is used to write, validate, and submit proposals for the Hubble Space Telescope and the James Webb Space Telescope.

The Space Telescope Science Institute is pleased to announce the release of APT 2020.1.1 and its associated documentation on January 22, 2020. This is the version of APT that needs to be used to support HST Cycle 28 Phase I submissions, and JWST GO Cycle 1 submissions. 

Release notes for JWST

An overview of the use and policy regarding the APT

For more explanations and to download the new APT you should consult

Results from the JWST Data Analysis User Survey

Between June 7 and August 2, 2019, an online user survey was conducted by STScI for focusing on the users’ needs and expectations for JWST data analysis software and training. Well over 400 users completed the survey, and the median time spent on the survey was just over 5 minutes. STScI greatly appreciated the response – the surveys represent a fundamental way for them to make data-driven decisions.

  • Here is a summary of some of the survey results:


    • – 59% of respondents identified as faculty/staff, with the remaining being students or postdocs. A similar distribution was already seen in a previous survey.
    • – Python is the most common language used, but more than 50% of respondents also use other major platforms (IRAF/IDL/Fortran+C) some of the time. Postdocs and students use Python at a significantly higher rate. Based on previous experience with other space observatories, almost 70% of users expect to start their data analysis efforts from individual, calibrated, or uncalibrated exposures.


  • – The JWST pipeline will produce higher-level products from the beginning of the mission. Almost 80% of users expect to download their JWST data from the archive and analyze it on a local machine. Users prioritize training specific to JWST, as opposed to general training in Python and non-specific analysis tools.
  • – Users identify a critical need for training materials that are available when needed (written documentation, help desk, colleagues, video tutorials). Scheduled training workshops are only identified as critically important by 10-20% of the community.

The results of the survey are already being used by STScI, the JWST project at GSFC, and the JWST Users Committee to help direct and prioritize efforts to develop software for use with JWST data.

The JWST ETC Cycle 1 Version 1.5 Is Now Live

STSCI announces the release of version 1.5 of the JWST Exposure Time Calculator (ETC), the final version prior to the Cycle 1 call for proposals. This release contains new instrument modes, as well as usability, performance, and accuracy improvements, including:

  • – New NIRCam Short Wavelength and Long Wavelength Imaging Time Series modes, including support for weak lens observations.
  • – New NIRSpec modes for MOS Confirmation Imaging, MOS Verification Imaging, and IFU Verification Imaging.
  • – Elimination of flat field errors for MIRI, NIRCam, and NIRISS time series modes. This enables estimates of the shot noise limit for exoplanet transit observations with very high signal-to-noise ratios.
  • – Changing the full-well depth for the NIRISS AMI mode to help users avoid the regime where charge can spill over between pixels. This decreases the saturation limit for NIRISS AMI by ~60%.
  • – New FASTGRPAVG readout pattern options for MIRI target acquisitions on fainter targets.
  • – Replacement of the NRS readout pattern with the new NRSRAPIDD6 for NIRSpec target acquisition. This now matches an operational change to improve the handling of cosmic rays.
  • – Addition of the neutral density filter to MIRI Imaging to support LRS Verification Imaging.
  • – Updates to Example Science Program Workbooks.
  • – Implementing a fix for a bug where the NIRSpec Multi-object Spectroscopy strategy offset the target in the wrong direction.
  • – Implementing a fix for incorrectly labeled Phoenix stellar model options.
See the release notes for details
Be sure to review the known issues for this release

As usual, your old workbooks are still available, but are marked read-only. Copying these workbooks will update them to version 1.5 so that you can continue working in the ETC.

APT 26.0.2 released

Please note that APT 26.0.2 has been released on May 14, 2018. This version of APT is a major JWST release. Please use this version of APT for your programs.

  • APT 26.0.2 contains the following changes you should be aware of:

    • – Pure Parallels: Improved the implementation of Pure Parallels
    • – NIRSpec MSA Planning tool: Numerous updates to the NIRSpec MSA Planning tool
    • Data Volume: Corrections to data volume calculations and a check at 1/2 recorder size
    • – Visit Coverage: Corrections to the visit coverage export file
    • Target Groups: Completed implementation of target groups


JWST beset by another problem as Northrop Grumman revamps training

From Stephen Clark, Spaceflightnow, May 8th, 2018:
Engineers working on the James Webb Space Telescope, which had its launch delayed to 2020 earlier this year, recently discovered another problem during testing at the observatory’s prime contractor Northrop Grumman in Southern California.

Teams at Northrop Grumman inspecting JWST’s spacecraft element after an acoustic test found fastening hardware had come loose, according to a NASA statement issued Friday. The spacecraft module, which will be mated to the observatory’s telescope section before launch, includes propulsion and power systems, plus a five-layer sunshield to keep the observatory’s telescope in shadow while in space.



NASA said in a statement Friday that the loose hardware discovered after the acoustic test was designed to fasten the sunshield’s membrane covers in place during launch.



  • The James Webb Space Telescope’s spacecraft element pictured during acoustic testing. 

  • Credit: NASA/Chris Gunn
NASA is reviewing options for repair and the next steps in spacecraft element launch environment testing. The team is reviewing the test data and hardware configuration and is actively working towards corrective action in the near future. We expect to get back to the environmental test flow shortly and continue to move safely and methodically toward mission success
Greg Robinson
Webb’s program director

In a statement, Robinson stressed the importance of ground testing to catch such problems.


“This is an example of why space systems are thoroughly and rigorously tested on the ground to uncover imperfections and fix them prior to launch,” Robinson said.

First reported by Space News, the discovery of the loose fasteners comes after NASA decided in late March to delay JWST’s launch from no earlier than March 2019 until around May 2020, and a prior schedule slip announced last year that pushed back the launch from October 2018 to 2019.


“It’s not terrible news, but it’s not good news, either,” Robinson said last week in a meeting of the National Academies’ Space Studies Board, according to Space News. Robinson said the fastening hardware included “washers and screws.”

When NASA announced the latest JWST launch delay March 27, officials described multiple concerns with the observatory’s spacecraft element, which was built by Northrop Grumman and is now undergoing environmental testing to ensure it can withstand the rigors of spaceflight.


Before the acoustic test, engineers put the spacecraft through a mechanical shock test to simulate the loads it will encounter when the observatory separates from its Ariane 5 launcher. The acoustic test subjected the spacecraft to the intense sound of a launch, while the vibration test — up next in the spacecraft test campaign — will simulate the shaking of a rocket ride.


“More time is needed to test and integrate the highly complex sunshield and spacecraft section at Northrop Grumman,” said Thomas Zurbuchen, associate administrator of NASA’s science mission directorate, in a briefing with reporters March 27. “ That is taking longer to complete, and there are also a few mistakes that happened. ”

The flagship mission will be the most ambitious astronomical observatory ever launched, building on a quarter-century of discoveries made by NASA’s famous Hubble Space Telescope. Originally proposed more than 20 years ago, the James Webb Space Telescope has been redesigned to expand its observing power and overcome numerous technical hurdles, ballooning costs from an original projection below $1 billion to more than $10 billion, a figure that includes planned launch and operations expenses, along with European and Canadian contributions.

The new observatory will be stationed nearly a million miles (1.5 million kilometers) from Earth, using a 21.3-foot (6.5-meter) mirror and four science instruments hidden behind a thermal sunshield to peer into the distant universe, studying the turbulent aftermath of the Big Bang, the formation of galaxies and the environments of planets around other stars.

Named for the NASA administrator who led the agency in the 1960s, the James Webb Space Telescope has already cost NASA $7.3 billion.
With the launch delay to 2020, the cost to develop the mission could rise above an $8 billion limit set by lawmakers to cover Webb’s development. If that happens, the mission must be reviewed and reauthorized by Congress. The rest of the funding covers launch costs borne by the European Space Agency for Webb’s ride into space on an Ariane 5 rocket, plus operating expenses after launch.


NASA officials identified several problems attributed to mistakes by the Northrop Grumman team: a damaged transducer that was incorrectly powered during testing, requiring replacement, valves in the spacecraft’s propulsion system that had to be replaced after they were improperly cleaned, and a catalyst bed heater that was overstressed at the wrong voltage. Engineers also found tears in the sunshield membranes during a deployment test to check how the thermal barrier will unfold to the size of a tennis court once in space, and it took longer than expected to deploy, fold and stow the sunshield.

Workers at Northrop Grumman will connect Webb’s spacecraft and telescope elements for combined testing before shipping the observatory to its launch base in French Guiana. JWST will launch with its sunshield, solar panels, antenna and telescope mirrors folded up for launch, then will go through a weeks-long process to deploy the parts on the way to its observing station at the L2 Lagrange point nearly a million miles (1.5 million kilometers) from Earth.

The telescope has completed its standalone testing at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and at the Johnson Space Center in Houston. It was delivered to Northrop Grumman’s Redondo Beach facility earlier this year. NASA said in March it would install more oversight over JWST in the future, including direct interaction with Northrop Grumman’s president and chief operating officer. NASA also planned to dispatch a project manager to Northrop Grumman’s factory in Southern California on a permanent basis, along with additional NASA spacecraft integration and test experts during critical operations. NASA also added daily and weekly schedule reviews with Northrop Grumman, which will also revamp its management structure. Northrop Grumman is also making personnel changes and updating procedures, officials said in March.

Some of the mistakes described in March were caused by poorly written procedures, NASA officials said.
JWST is a “first-of-a-kind” mission and marks a “huge technological leap” in spacecraft development.When people are doing things for the first time ever, there is learning that happens. So we are ensuring that all of the training that we’re giving our people continues to be a focus, so that we can give them the best chance of success. Doing something for the first time does come with inherent risks, and we and NASA are partnering to identify that and successfully mitigate it, so that we can get this successfully launched and able to fulfill this space exploration mission that we all want to see be successful. The good news is now we have all the flight hardware.The new launch date does reflect additional time for integrating and testing the telescope and the spacecraft, and it’s important for us that mission assurance is the top priority.
Kathy Warden
Northrop Grumman’s president chief operating officer, in an April 25 conference call with investment analysts

An independent review board chaired by Thomas Young, a space industry veteran who served as an executive at Lockheed Martin and as mission director of NASA’s Viking Mars landers, will complete a report examining JWST’s technical, schedule and budget issues around the end of May.The review will help NASA confirm a new launch date, now expected around May 2020, and a new cost estimate for the mission.

And from Space News, May 3rd , 2018: 


WASHINGTON As an independent review of NASA’s James Webb Space Telescope continues, the project is dealing with a new problem discovered in recent testing of the spacecraft.
In a presentation at a meeting of the National Academies’ Space Studies Board here May 3, Greg Robinson, the JWST program director at NASA Headquarters, said some “screws and washers” appear to have come off the spacecraft during recent environmental testing at a Northrop Grumman facility in Southern California.

Technicians found the items after the spacecraft element of JWST, which includes the bus and sunshield but not its optics and instruments, was moved last weekend from one chamber for acoustics tests to another to prepare for vibration testing. Right now we believe that all of this hardware — we’re talking screws and washers here — come from the sunshield cover. We’re looking at what this really means and what is the recovery plan.The problem was only a couple of days old, and we have few additional details about the problem. It’s not terrible news, but it’s not good news, either
Greg Robinson
Webb’s program director
The incident, Robinson argued, showed the importance of the wide range of tests the spacecraft is put through prior to launch. “That’s why we do the testing,” he said. “We do it now, we find it now, we fix it and we launch a good spacecraft
  • The optical element of NASA’s James Webb Space Telescope is removed from a shipping container in a Northrop Grumman clean room in March. The spacecraft element, including the folded-up sunshield, is at left prior to undergoing acoustic testing.
  • Credit: Northrop Grumman

This latest incident comes as an independent review board, chartered by NASA in late March after announcing a one-year delay in JWST’s launch because of other technical issues, is in the midst of its analysis of the mission and its launch readiness. That review, led by retired aerospace executive and former NASA Goddard director Tom Young, is scheduled to be completed at the end of the month.



It was a no-brainer to put an independent review board in place,” Thomas Zurbuchen, NASA associate administrator for science, said at the Space Studies Board meeting May 2. The board, he said, will provide an independent look at the status of the mission and identify what needs to be done to ensure the mission will be successful. Zurbuchen said there would be a “little bit of a pause” after the board delivers its final report, in part because of a prior commitment by Young in early June that makes him unavailable for discussions about the report or additional work. 



He said NASA will start briefing Congress and others about the report, and the agency’s response, in late June. That report will allow NASA to refine a launch date of approximately May 2020 that it announced March 27. 


Robinson believed there was margin in the revised development schedule to maintain that date.


We believe we have good margin there, and a lot that margin is for things like we just experienced. I still believe we’ll go in 2020, in roughly the same time frame that we talked about, unless this problem takes longer than we expect. One lesson already learned, was the need for more NASA oversight of Northrop Grumman’s work. We had people in the plant for a long time, four or five people. We’ve added a lot of folks in the past five or six months for oversight at Northrop Grumman
Greg Robinson
Webb’s program director

ETC Version 1.2.2 Released

The JWST Exposure Time Calculator (ETC) version 1.2.2 has been released on March 19, 2018. This is a patch release to the JWST ETC V1.2.

The patch release version 1.2.2 includes the following accuracy improvements and features :

– Residual flat-field errors are reduced with multiple exposures treated as dithers.

  • – Improved accuracy with redesigned and better-sampled PSFs for NIRCam and MIRI coronagraphy modes, and MIRI coronagraphic target acquisition
  • – Inclusion of pupil mask for NIRISS imaging in long-wavelength filters.
  • – Enhanced coronagraphy strategy with four options available for PSF subtraction.
  • – Saturation is reported separately for both nod positions for NIRSpec IFU and MIRI MRS.
  • – Coronagraphy modes report saturation for the science scene and PSF subtraction source separately.
  • – Performance and robustness improvements.

For more information and details, see the section « Observing Tools » in the Expertise Page of the site.

MIRISim Released

The MIRI software team is pleased to announce the public release of the MIRI Simulator software package, MIRISim (April 9, 2018).

MIRISim has been built, in Python, to simulate the optical path through MIRIM, the MIRI Imager, and both the Low and Medium Resolution Spectrometers (LRS and MRS, respectively).

It takes as input either a user defined ‘scene’ or a FITS file, and simulates an observation based on user defined Imager filters or MRS channels, and exposure parameters (number of groups, integrations, etc). The results are JWST ‘level 1B’ data which are suitable for processing with the JWST pipeline. The data produced by MIRISim is consistent with the MIRI sensitivity model, but should not be used as a replacement for the JWST Exposure Time Calculator (ETC).
  • The download instructions are available at the MIRISim
  • MIRISim is available on an as-is, best-effort basis, and information about MIRISim and example use cases.
  • The MICE team has released a description of MIRISim

A Userguide with some exemples

The current version is Python 2.7 based, with a planned update to Python 3 coming soon. To be kept up to date with MIRISim developments, including announcements of new releases, please sign up to the announcement list.