News

On the trail of 1.8 billion stars

The motions of 40 000 stars across the sky over the next 400 thousand years, calculated from Gaia observations. Each trail representing the displacement of one star. Credit: ESA/Gaia/DPAC, CC BY-SA 3.0 IGO

On the trail of 1.8 billion stars

3 December 2020. Spanning a period of 34 months, the ESA Gaia mission has now published the first part of its third data release (EDR3). It provides the most precise measurements of positions and m...

The Gaia space telescope measures fundamental characteristics of stars and other celestial objects at a level of precision never achieved before. This extensive sky survey provides the basic observational data to tackle an enormous range of key questions in various fields of astrophysics. The main focus lies on the study of structure and evolutionary history of our galaxy.

"Gaia catalogues will be the reference database for future generations of astrophysicists. Already now, about five scientific publications are published based on Gaia data every day. Measured by the number of publications, this is the most successful astrophysical mission ever", explains Dr Katja Weingrill, PI of the Gaia project at the AIP.

The now published early data release 3 (EDR3) is based on data collected between 25 July 2014 and 28 May 2017, a period of 34 months. As a comparison, the second data release was based on 22 months of data and the first one was based on observations collected during the first 14 months of Gaia's routine operational phase.

The 1.8 billion objects in the new Gaia catalogue mainly comprise stars in the Milky Way, but also distant galaxies and quasars, and closer objects in our solar system. The measurements from 12 additional months of observation not only increased the number of objects in the catalogue, but also made the incredible precision of the measurements possible. The accuracy of the parallaxes - and thus their distance determination - has been increased by 30 percent and the accuracy of the stars' movements across the sky has doubled compared to the last catalogue. This was possible because of the larger number of observations processed for Gaia EDR3 and the larger time difference between the first and last observation.

In order to process the overwhelming amount of data that Gaia produces, a consortium of more than 500 scientists and software developers, the Data Processing and Analysis Consortium (DPAC) was formed. Scientists at the AIP contribute to the DPAC with three parts: the background correction for Gaias spectral instrument, a software pipeline reducing additional data from dense areas on the sky, and the scientific exploitation of the Gaia data by providing the public Gaia archive.

Alongside with the catalogue, the scientists from DPAC released a set of four science verification papers that demonstrate the quality of the new Gaia catalogue. One of them was written with a contribution from the AIP Gaia Team and analyses the Magellanic Clouds, the two galaxies that orbit the Milky Way. Gaia EDR3 data enables it to clearly separate the stellar population of the large Magellanic Cloud into different age classes for the first time - from 50 million year young stars to several billion years old ones. It could be shown that the younger stars move faster around the centre of the Large Magellanic Cloud than the older ones. A movement of mostly young stars in the bridge between the two clouds towards the Large Magellanic Cloud could be verified for the first time.

As for previous releases, the Gaia data is made available through the Gaia Partner Data Centres, one of which is the AIP. The AIP Gaia Archive provides most convenient ways for scientists and other interested parties to work with the precious data. Dr Harry Enke, responsible for the AIP data archive, explains: “The user-friendly interface on the webpage gaia.aip.de allows researchers from all over the world to access, filter and process the data they need in a very flexible way. It offers services like SQL query submission, cone search facilities, a private database space for users, and Virtual Observatory based access via scripting as well as additional catalogues and cross-match tables.”

This infographic gives an overview of the contents of Gaia Early Data Release 3. Credit: ESA/Gaia/DPAC

Science contact

Dr. Katja Weingrill, +49 331 7499 671, kweingrill@aip.de

Media contact

Franziska Gräfe, 0331 7499 803, presse@aip.de

More information

ESA press release: http://www.esa.int/Science_Exploration/Space_Science/Gaia/Gaia_s_new_data_takes_us_to_the_Milky_Way_s_anticentre_and_beyond

General information on Gaia EDR3: https://www.cosmos.esa.int/web/gaia/earlydr3

Gaiadata access: https://www.cosmos.esa.int/web/gaia/data-access#PartnerDataCentres

Gaia Data Center at AIP: https://gaia.aip.de

 

The key areas of research at the Leibniz Institute for Astrophysics Potsdam (AIP) are cosmic magnetic fields and extragalactic astrophysics. A considerable part of the institute's efforts aim at the development of research technology in the fields of spectroscopy, robotic telescopes, and e-science. The AIP is the successor of the Berlin Observatory founded in 1700 and of the Astrophysical Observatory of Potsdam founded in 1874. The latter was the world's first observatory to emphasize explicitly the research area of astrophysics. The AIP has been a member of the Leibniz Association since 1992.

Read more ...
With 35,000 eyes in the sky: world's largest fibre spectrograph completed

Dome of the 10-metre Hobby-Eberly Telescope at McDonald Observatory in Texas. Credit: Ethan Tweedie Photography

With 35,000 eyes in the sky: world's largest fibre spectrograph completed

2 December 2020. Astronomers from the Leibniz Institute for Astrophysics Potsdam (AIP), together with colleagues from Germany and the US, have completed an astronomical spectrograph that is capable...

The discovery of the accelerated expansion of the universe through the observation of distant supernovae has led to the postulation of the so-called Dark Energy. Up to now, the nature of this “anti-gravity”, that drives the universe apart, is unknown. This has initiated various scientific projects, such as the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). HETDEX aims to create a three-dimensional map of 2.5 million distant galaxies that will help astronomers understand how and why the expansion of the universe is speeding up over time.

“To be able to determine the distances of remote galaxies, astronomers must not only find these faint objects, but also analyze their light spectroscopically, i.e. disperse it into the different wavelengths”, explains Dr Andreas Kelz, the local HETDEX project leader at AIP. For this purpose, a powerful multi-channel spectrograph called VIRUS has been built. It is connected to the telescope by a system featuring 35,000 optical fibres, that have been developed, assembled and tested at AIP. With the completion of the full instrument and its installation at the 10-metre telescope at McDonald Observatory in Texas, a milestone has been reached. VIRUS, the Visible Integral-field Replicable Unit Spectrograph, is actually a massive machine made up of dozens of copies of optical fibre bundles and spectrographs working together for efficiency.

“While it took a decade to build and install the full instrument, the modular approach of the system allowed a step-by-step implementation, so that the scientific survey could already commence three years ago with the first modules of the instrument in place.”, explains Kelz. This approach not only contributes to cost reduction, but also allowed for technology transfer and commercial manufacturing with industrial partners.

The astronomical survey works by aiming the telescope at two regions of the sky near the Big Dipper and Orion. For each pointing, the telescope currently records around 32,000 spectra, simultaneously, capturing the cosmic fingerprint of the light from every object within the telescope’s field of view.

To produce the map needed for the project, astronomers will combine one billion spectra and in particular search for distant galaxies. These galaxies range in distances from 10 billion to 11.7 billion light-years away, so they represent an epoch when the universe was only a few billion years old. Their spectra carry information about how fast the galaxies are moving away from us as a result of the expansion of the universe.

HETDEX already released 15,000 observations with over one million detections of astronomical objects. AIP scientist Prof Dr Lutz Wisotzki who is a member of the HETDEX steering committees explains: “These data are opening a gold mine for the diverse research interests at our institute, from the oldest stars in the Milky Way halo via active black holes in the centre of galaxies to the gaseous envelopes of infant galaxies in the young universe.”

HETDEX is a large international collaboration. The project is led by The University of Texas at Austin McDonald Observatory and Department of Astronomy with participation from Penn State University; Ludwig Maximilians University, Munich; the Max Planck Institute for Extraterrestrial Physics; the Institute for Astrophysics, Gottingen; the Leibniz Institute for Astrophysics, Potsdam; Texas A&M University; The University of Oxford; the Max Planck Institute for Astrophysics; The University of Tokyo; and the Missouri University of Science and Technology.

The AIP, the innovation centre for fibre spectroscopy and sensing innoFSPEC and the BMBF supported the Potsdam contributions for HETDEX.

 

The focal plane of the Hobby-Eberly Telescope. Starlight hits an array of 78 fibre plugs (each containing 448 glass fibres) instead of a camera. These guide the light to over 150 connected spectrographs, where it is analysed. Credit: J. Pautzke/E. Mrozinski/G. Hill/HETDEX Collaboration

 

Science contact

Dr. Andreas Kelz, 0331 7499 640, akelz@aip.de

Prof. Dr. Lutz Wisotzki, 0331 7499 532, lwisotzki@aip.de

Media contact

Franziska Gräfe, 0331 7499 803, presse@aip.de

 

The key areas of research at the Leibniz Institute for Astrophysics Potsdam (AIP) are cosmic magnetic fields and extragalactic astrophysics. A considerable part of the institute's efforts aim at the development of research technology in the fields of spectroscopy, robotic telescopes, and e-science. The AIP is the successor of the Berlin Observatory founded in 1700 and of the Astrophysical Observatory of Potsdam founded in 1874. The latter was the world's first observatory to emphasize explicitly the research area of astrophysics. The AIP has been a member of the Leibniz Association since 1992.

Read more ...

Gaia New Data Release

A first part of the third Gaia data catalogue will be published on Thursday 3 December 2020. By then, entries for 1.8 billion sources will be available.

On this occasion, DLR, together with the Leibniz Institute for Astrophysics Potsdam (AIP) and the other participating German institutes, is inviting to an online event to present the uniqueness of the early data release 3 and the Gaia mission to the public.

 

The event will be public, registration is not necessary.

Thursday, 3.12.2020, 11.00 to 12.30

https://event.dlr.de/event/gaia-early-data-release-3/

 

The event will be fully in German, but other countries are also organizing events in different languages:

https://www.cosmos.esa.int/web/gaia/edr3-events

 

The key areas of research at the Leibniz Institute for Astrophysics Potsdam (AIP) are cosmic magnetic fields and extragalactic astrophysics. A considerable part of the institute's efforts aim at the development of research technology in the fields of spectroscopy, robotic telescopes, and e-science. The AIP is the successor of the Berlin Observatory founded in 1700 and of the Astrophysical Observatory of Potsdam founded in 1874. The latter was the world's first observatory to emphasize explicitly the research area of astrophysics. The AIP has been a member of the Leibniz Association since 1992.

Read more ...
Grant for research on satellite galaxies

Dr. Marcel Pawlowski. Credit: Jamie Kanehisa

Grant for research on satellite galaxies

27 November 2020. Dr Marcel Pawlowski from the Leibniz Institute for Astrophysics Potsdam (AIP) receives funding in the Leibniz competition to establish a junior research group dedicated to the mot...

Our immediate cosmic neighbourhood is called the Local Group. It consists of two large spiral galaxies, the Milky Way and Andromeda. Both are several million light years apart and surrounded by dozens of smaller satellite galaxies of lower mass. The cosmological standard model provides information about the evolution of the universe from the Big Bang to the galaxies of today. On cosmologically large scales - i.e. applied to the universe as a whole - this model is very successful. It makes precise predictions, which have been confirmed to the percentage range. However, the model implies that most of the total mass of the known universe is made up of the so called dark matter. Since it is a source of gravity, it has a direct effect on the motion and interaction of galaxies - thus determining the choreography. Simulations show that the many small satellite galaxies should arrange and move almost randomly around massive galaxies. However, much more ordered distributions were observed in the Local Group.

The funded project of Dr Marcel Pawlowski and his team will use simulations as well as observations and test the cosmological standard model on the scale of the satellite galaxies. Do they dance as chaotically as predicted, or do they also follow a more ordered cosmic choreography and what is its origin? "The project will either reconcile the existing cosmological theory with current observational data - or reinforce the current discrepancy and thus provide information about the nature of dark matter," says Dr Marcel Pawlowski, explaining the research group's goal. The funding will extend over 5 years.

Dr Marcel Pawlowski is a Schwarzschild Fellow at the Leibniz Institute for Astrophysics Potsdam (AIP) since 2018. Prior to that he was a NASA Hubble Fellow at the University of California in Irvine and a postdoctoral fellow at Case Western Reserve University in Cleveland, Ohio.

The programme "Leibniz-Junior Research Groups" is one of four funding programmes of the Leibniz Competition and is aimed at postdocs with an excellent scientific career. As leaders of junior research groups, they are given the opportunity to realise their own research projects and further establish themselves in their respective research field. With this funding format, the Leibniz Association offers them attractive research conditions and networking opportunities.


Science contact

Dr. Marcel Pawlowski, 0331 7499 342, mpawlowski@aip.de

Media contact

Franziska Gräfe, 0331 7499 803, presse@aip.de

 

The key areas of research at the Leibniz Institute for Astrophysics Potsdam (AIP) are cosmic magnetic fields and extragalactic astrophysics. A considerable part of the institute's efforts aim at the development of research technology in the fields of spectroscopy, robotic telescopes, and e-science. The AIP is the successor of the Berlin Observatory founded in 1700 and of the Astrophysical Observatory of Potsdam founded in 1874. The latter was the world's first observatory to emphasize explicitly the research area of astrophysics. The AIP has been a member of the Leibniz Association since 1992.

Read more ...
Virtual Babelsberg Starry Night on 19 November

A young stellar cluster in the star forming region 30 Doradus. Credit: NASA, ESA, and F. Paresce (INAF-IASF, Bologna, Italy), R. O'Connell (University of Virginia, Charlottesville), and the Wide Field Camera 3 Science Oversight Committee

Virtual Babelsberg Starry Night on 19 November

The next lecture of the virtual Babelsberg Starry Nights of the Leibniz Institute for Astrophysics Potsdam (AIP) will be broadcasted on Thursday, 19 November 2020 on the YouTube channel "Urknall, W...

On Thursday, starting at 6 p.m., the lecture on the topic "The origin of stars" from the Babelsberg Starry Night series will be online. Dr. Philipp Girichidis, researcher in the Cosmology and High-Energy Astrophysics section at the AIP, will explain how stars are born,  where in the interstellar medium and under what physical conditions stars and stellar clusters can form, and will also go into the characteristics of molecular clouds. The lecture will be held in German.

This season, the Babelsberg Starry Nights will not take place on site at the AIP, but will come straight to your home: on the 3rd Thursday of each month from 6 p.m. the lectures are available at

https://www.aip.de/babelsberger-sternennaechte

and can be viewed at any time afterwards.

 

Further dates: Babelsberg Starry Nights

 

 

Flyer:

The key areas of research at the Leibniz Institute for Astrophysics Potsdam (AIP) are cosmic magnetic fields and extragalactic astrophysics. A considerable part of the institute's efforts aim at the development of research technology in the fields of spectroscopy, robotic telescopes, and e-science. The AIP is the successor of the Berlin Observatory founded in 1700 and of the Astrophysical Observatory of Potsdam founded in 1874. The latter was the world's first observatory to emphasize explicitly the research area of astrophysics. The AIP has been a member of the Leibniz Association since 1992.

Read more ...