An important event for astronomy begins today: the Science and Technical Sub-Committee of the UN Committee on the Peaceful Uses of OuterSpace. ( #COPUOS).
Why is this important for astronomy?
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The International Astronomical Union @IAU_org along with 5 #COPUOS Members (Chile, Ethiopia, Jordan, Slovakia, Spain) will submit a paper that makes recommendations to protect our Dark and Quiet Skies for the benefit of humanity. 2/...

We aim that astronomy can co-exist with exciting technological developments in the space sector, and humankind in general. We are asking for a political committment from COPUOS members to recognise that dark and quiet skies is an issue for COPUOS to take onboard. 3/...

Previously, threats to astronomy were mainly local, but with the addition of 10,000s of satellites and growing cities spreading light polllution far, we can't rely on locally agreed radio quiet zones and dark-sky ordinances. 4/...

On the topic of #satelliteconstellations we've had positive interaction with industry and found practical solutions. We can take this approach with 5, maybe 10 individual companies, but it's not a sustainable approach in the long-term. 5/....

We have a situation where the activities of a single private company or single government in space can have #global #impact. This indicates the need for #global guidelines and thinking on how to have #sustainable space activities. #LTS. 6/...

For this reason @IAU_org with the mandate of #COPUOS & @UNOOSA support made a study with the input of 100s of experts and a conference in Oct 2020. The report details policy recommendation on light pollution, radio astronomy & satellite constellations https://www.iau.org/news/announcements/detail/ann21002/ 7/..

The recommendations are summarised in the UN paper. Behind the scenes we've been working to contact COPUOS delegations. Many countries will either voice support for the recommendations, or suggest that COPUOS should adopt the topic in the future! 8/... https://www.unoosa.org/res/oosadoc/data/documents/2021/aac_105c_12021crp/aac_105c_12021crp_17_0_html/AC105_C1_2021_CRP17E.pdf

. @ESO has been part of this working group and as observers of #COPUOS, have been using our networks to raise awareness of the issue and support working groups in a Member States to study the subject. 9/...

The UN Committee is livestreamed here: https://www.unoosa.org/oosa/en/ourwork/copuos/stsc/2021/index.html The @IAU_org presentation is due for the Thu 22 AM session. See also a technical presentation by Connie Walker on Wed 21 AM session. https://www.unoosa.org/documents/pdf/copuos/stsc/2021/Technical_Presentation_List_-_2021_STSC.pdf 10/...

If #COPUOS takes up the subject, then we have a truly global forumlooking at how to implement these recommendations in national and international regulation and guidlines #sciencepolicy #SciPol #Sciencediplomacy 11/...

Here is a shout-out to all who participated in this work @RobertMMassey @giulianarotola @FedeDiVruno @astrokiwi @merrdiff @moribajah @melipalSC @esa @ESO @JohnBarentine @clmuddjr and many more without twitter accounts! 12/...End

At #COPUOS - #NobelLaureate @DidierQueloz presents the importance of the #global nature of the impact of satellite constellation on our #darksky and on #astronomy, and the need for global solutions.

Update from Monday 19 April session of #STSC #COPUOS
Austria , Germany and Switzerlandrecognise the importance of our #DarkandQuietSkies project in their national statements
The @IAU_org presentation should take place on 21 Apr in the morning session.

Update from Tue 20 April session of #STSC #COPUOS
Finland welcomes the @IAU_org paper
Belgium expresses concern about the preservation of the night sky
Join us at 10:00 CEST 21 April for a technical presentation of our policy recommendations https://www.unoosa.org/oosa/en/ourwork/copuos/stsc/2021/index.html

Fantastic presentation today at #STSC #COPUOS from Dr Connie Walker, @IAU_org representative, on the details of the policy recommendations from the #DarkandQuietSkies workshop

Some details of the concerns of the #astronomy community on #satelliteconstellations

Main #policy recommendations:
-Encourage #collaboration & #stewardship of the #nightsky
-Formulate satellite licensing requirements, guidelines & standards to account for impacts on astronomy
-Support the development of space domain decision intellitegence (incl. data sharing)

Operator recommendations:
-Minimise orbital altitude, # satellites & time in orbit when not active
-Reduce brightness to below unaided eye visibility and 7th mag at 550km for observatories
-Avoid direct & indirect illumination of radio observatories

Finally - the specific objective of our actions at UN #COPUOS .
The #DarkandQuietSkies conference is being planned for October 2021 in La Palma, hosted by @IAC_Astrofisica

Update from Wed 21 April session of #STSC #COPUOS
IAU presentation of the CRP
Romania , Chile , Australia note the importance of astronomy in their national statements
Chile makes statement supporting IAU proposal for a new #STSC agenda item on #DarkandQuietSkies