Registration

The conference will be held at the Haus der Astronomie (HdA) at MPIA in Heidelberg. HdA is the Center for Astronomy Education and Outreach in Heidelberg; more information about the center and its facilities and resources here.

We are excited to accept abstracts for contributed talks on topics ranging from experimental data to models:
Interior structure models
Intercomparison of interior models
Evolution models
Atmosphere-interior interactions
Equations of State
Solubility
Opacity

To register for the conference and optionally submit an abstract, please fill in and submit the Registration Form. Registration will close on 15 January 2026.

Conference fees

The conference fee covers all events happening at the venue, including coffee breaks, lunches and reception. We cannot offer travel or lodging support.

In-person participation: 165€
Online participation: no cost

We will send the notification of confirmed in-person and online participants 2 months before the conference. Confirmed in-person participants will be sent a link to our conference fee payment system by email.

Schedule

Venue

The conference will be held at the Haus der Astronomie (HdA) at MPIA in Heidelberg. HdA is the Center for Astronomy Education and Outreach in Heidelberg; more information about the center and its facilities and resources here.

Accessibility

HdA is accessible to disabled persons, and dedicated parking spaces are available. Unfortunately, the buses dedicated to the event and public transportations may not be accessible for everyone. However, there are specific taxi services in Heidelberg that we can arrange on-demand. Don't hesitate to contact us if you need any assistance or have any questions.

Note that mobile phone connectivity at/around the HdA is at best poor but usually non-existent. But once connected to MPIA guestnet on-site you can also use your phone via wifi-calling.

Address

Max Planck Institute for Astronomy
Königstuhl 17
69117 Heidelberg, Germany

Logistics

The conference will start at 09:00am on Monday, April 13 2026, and finish at 4:00pm on Friday, April 17 2026 (CEST/UTC+2).

We will have a conference Slack channel for communication. We will send participants an invitation link to the Slack channel in an overview email once the participant list is confirmed. If you cannot access Slack, please let us know.

There will be a dedicated bus to bring participants from the town to the conference venue (see details under travel below). Participants are responsible for organizing their travel to Heidelberg and should make their own accommodation arrangements (see below).

Childcare

If you need help with childcare arrangements, don't hesitate to contact us.

Lunch & Coffee Breaks

The conference provides lunch and coffee breaks at the venue on all days. If you have any additional dietary requirements (and may not have indicated so in your registration form), please email Carola Jordan well in advance.

Conference Dinner

To foster interactions between participants, we will be organizing a dinner (restaurant to be announced by email and Slack). Each attendee will be responsible for paying for their own dinner. If you wish to attend, please indicate so by filling out the registration form so we can make the appropriate reservation.

Accessibility

We are committed to providing an accessible environment for all participants. If you need help or arrangements, don't hesitate to contact the organizers.

Participants will pay attention not to leave out information for some people in your audience. Some of us might not be able to see well, hear well, move well, speak well, or understand information presented in some ways well or at all. Everyone at the event will be open to diversity in the audience and any accessibility issues. The Web Accessibility Initiative provides some information & directions.

Accommodation

Participants are responsible for making their own accommodation arrangements. Heidelberg has plenty of hotel and Airbnb options; the following hotels are some suggestions (but we don't endorse any particular hotel).

1. Hotel Vier Jahreszeiten, Haspelgasse 2, Heidelberg
2. Hotel Goldene Rose, St. Anna Gasse 7, Heidelberg
3. Hotel Anlage, Friedrich-Ebert-Anlage 32, Heidelberg
4. Hotel Monpti, Friedrich-Ebert-Anlage 57, Heidelberg
5. GuestHouse Heidelberg, Bergheimer Straße 24, Heidelberg
6. Bergheim 41, Bergheimer Straße 41, Heidelberg
7. Leonardo Hotel, Bergheimer Straße 63, Heidelberg
8. Qube Hotel, Bergheimer Straße 74, Heidelberg
9. Hotel NH, Bergheimer Straße 91, Heidelberg

Please don't hesitate to contact us if you have any questions.

Travel

Visas

You may need to apply for a visa to enter Germany. See this overview of visa requirements. Feel free to contact the organizers if you need a letter of support.

Getting to Heidelberg

Flight

We recommend flying to Frankfurt Airport (FRA), as this is the nearest international airport to Heidelberg. The following directions to Heidelberg assume that you are starting from Frankfurt.
Deutsche Bahn (DB) has connections from Frankfurt Airport (station: Frankfurt(M) Flughafen Fernbahnhof) to various train stations around Heidelberg (likely either Hauptbanhof or Altstadt, depending on where your hotel is). Train tickets cost 45 € and can be pre-booked online or purchased at the ticket machines at the train station "Frankfurt (M) Flughafen Fernbf." This route requires a transfer, which is recommended as the "Fernbf" train station is right next to the terminals and there are many daily connections. The transfer takes an hour. From there, you can take a cab or public transportation from the main train station in Heidelberg to your final destination. We do not recommend the cheaper "saver" tickets, as these apply to the specific booked train -- You cannot use them on a different train if you have flight delays.
The best shuttle option is Transfer & Limousine Service (TLS) (90 € one way). The TLS shuttle has fixed departure times in Frankfurt. The timetable and prices for the shuttle can be found here. If you miss the shuttle, you can take the next available one. Drop-offs and Pick-ups in Heidelberg must be specified individually (e.g. your hotel or MPIA).

Train

Deutsche Bahn (DB) has connections to various train stations around Heidelberg (likely either Hauptbanhof or Altstadt, depending on where your hotel is). Typically you will have a connection in Mannheim and change platforms there for the S-Bahn to Heidelberg. Trainline could also help you plan your journey across multiple countries and train companies.
Although there are no barier gates in Germany, you will need to buy a ticket before stepping into the trains. The controls are frequent. You can buy tickets online or at ticket machines or for S-Bahn (and local buses) on the eVRN app.

Bus

A cheaper but slower alternative is the "Flixbus" from the airport to Heidelberg. The prices range from 5 to 15 € each way, but depending on the time of day, the trip could take up to three hours due to stops and traffic. To investigate timetables and book tickets, you can check out the Flixbus website.

Driving/Taxi

If you decide to rent a car and drive, you can follow these directions (to MPIA).

Alternatively, you can take a taxi via ABC Taxi Service from Frankfurt to Heidelberg. ABC Taxi Service is cash payment only. To make a reservation, email ABC Taxi Service at taxikunze@aol.com. In the reservation, mention that you are a guest at an MPIA conference to receive a discount. The cost of this taxi service will be:
- From Frankfurt to Heidelberg (your hotel): 119 € one way plus 15 €/20 minutes, if waiting time applies.
- From Frankfurt to MPI: 129 € one way plus 15 €/20 minutes, if waiting time applied.

Getting to HdA

You can find how to get to Heidelberg and the MPIA/HdA campus here. There will be a shuttle to transport participants from the town center up the hill to MPIA/HdA every morning. It will leave from behind Hotel NH on Bergheimer Strasse at 08:25 (bus/company name "Discipulus").

It will then stop on the hillside of Klingenteichstrasse, in front of Joswig & Partner Steuerberater (the stop on the south side of the road, i.e., the one closest to the hill) at 08:30.

The bus might arrive five minutes later here, but be there no later than 08:30 as the bus cannot wait). A local participant will be at each pick-up point and travel on the bus. A bus will bring participants back into town (the same two stops) after each day's conference.

Conference bus itinerary

At other times of the day, you can take Bus 30 - the "Science Bus" - up to MPIA (the bus will drop you off right outside HdA) or back down the hill. You can buy tickets online or at ticket machines or (if that fails) from the driver on the bus (the cost is approximately 2.50 € each way) or on the eVRN app. Note that where the If you are travelling during rush hour please aim to take the conference shuttle rather than the “Science Bus" since it can already be quite full with MPIA employees.

Exploring Heidelberg

The easiest way to explore Heidelberg is by foot. The Rhein-Neckar-Verkehr (RNV) provides public transportation in Heidelberg with buses and trams; these can take you more or less anywhere you want to go within the city. The timetables can be found online.