🛰️ Streamlit Space Explorer

Explore NASA data in one elegant app: APOD with share cards & favorites, a NASA Images search gallery, a live Earth events map (EONET), and a Near-Earth Objects mini-terminal — built with Streamlit

Built with the tools and technologies:

Python | Streamlit | Pandas | PyDeck | Requests | Pillow | qrcode | PyMongo

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Screenshot

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Table of Contents

• Overview
• Features
• Getting Started
  • Project Structure
  • Prerequisites
  • Installation
  • Configuration
  • Usage
• Design Notes
• Limitations
• Roadmap
• License
• Contact
• References

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Overview

Streamlit Space Explorer is a recruiter-friendly Streamlit app showcasing practical API integration, caching, and persistence:

• APOD (Astronomy Picture of the Day): browse by date, random picks; export branded share cards; save favorites to MongoDB.
• Space Search Gallery (NASA Images & Video Library): search 140k+ public assets (no key); open full-resolution originals.
• Earth Events (EONET v3): live natural events (wildfires, storms, volcanoes, sea/ice) with a map and filters.
• NEOs This Week (NeoWs): digest of near-Earth objects with date search, sizes, miss distance (km/LD), and speed.

Secrets are stored via Streamlit secrets.toml locally and through Streamlit Community Cloud on deploy.

Project Highlights

• Polished UX: sidebar page switcher, tabs, expander help, toasts, dark/light toggle, deep links via query params, and PNG share-card export.
• Robust engineering: @st.cache_data and @st.cache_resource, typed helpers, graceful errors, MongoDB indexes, and input validation.
• Clean architecture: services/ for APIs & DB, components/ for share-card, single entrypoint app.py.

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Features

• 🖼️ APOD: daily image/video, description, copyright; share-card export (QR + overlay); MongoDB favorites.
• 🔎 NASA Images Gallery: query by keyword; preview grid; open originals; optional favorite save.
• 🌍 EONET (v3): filter by category, status (open/closed), and look-back window; map and list with links to details.
• 🪨 NeoWs: choose a single date or ≤7-day range; table with Potentially Hazardous?, diameter min/max (m), closest time, miss distance (km/LD), relative speed (km/s), and More info link; inline glossary.
• 🌓 Theme toggle: runtime dark/light switch (demo-friendly).
• 💾 Persistence: favorites stored in MongoDB Atlas with unique index (user_id, apod_date).
• 🚀 Performance: strategic caching and pagination; requests tuned with timeouts; minimal reruns.

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Getting Started

Project Structure

streamlit-space-explorer/
├─ app.py
├─ components/
│  └─ share_card.py
├─ services/
│  ├─ apod.py
│  ├─ db.py
├─ .streamlit/
│  ├─ config.toml
│  └─ secrets.toml          # local only; do NOT commit
├─ requirements.txt
└─ README.md

Prerequisites

• Python 3.9+
• NASA API key (free) for APOD/NeoWs/EONET if rate limits apply — generate at api.nasa.gov.
• MongoDB Atlas free cluster (optional; used for favorites).

Installation

1. Create & activate a virtual environment:

    python -m venv .venv
    # Windows:
    .venv\Scripts\activate
    # macOS/Linux:
    source .venv/bin/activate
   

2. Install dependencies:

    pip install -r requirements.txt
   

Configuration

Create .streamlit/secrets.toml (local) and paste your keys (example):

    [api]
    nasa_apod_key = "YOUR_NASA_KEY"

    [mongo]
    uri        = "mongodb+srv://apod_app:YOUR_PASSWORD@cluster0.xxxxx.mongodb.net"
    db_name    = "space_gallery"
    collection = "favorites"

• Access in code with st.secrets["section"]["key"] or attribute style (st.secrets.api.nasa_apod_key).
• On Streamlit Community Cloud, paste the same TOML content in your app’s Secrets (do not commit the file).

Usage

Run locally:

    streamlit run app.py

Workflow:

1. Use the sidebar Pages to switch: APOD, Space Search Gallery, Earth Events, NEOs This Week.
2. In APOD, pick a date or random → preview → export a share card → ⭐ to save in favorites.
3. In Gallery, search e.g., “Aurora” → open original → (optional) save as favorite.
4. In Earth Events, filter and explore on the map; open event detail links.
5. In NEOs, search by single date or a ≤7-day range; sort table; open “More info”.

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Design Notes

• APIs chosen for broad appeal & low friction

  • APOD: iconic daily image/video, small JSON schema; great for demos.
  • NASA Images & Video Library: no key required; /search and /asset/{nasa_id} cover most gallery needs.
  • EONET v3: human-readable categories & events; works well with maps.
  • NeoWs: approachable feed with dates and close-approach details (≤7-day windows).

• Secrets & deployment
  Native secrets.toml keeps keys out of your repo locally, and Streamlit Cloud provides a secure Secrets UI on deploy.

• Caching strategy
  @st.cache_data for pure fetch/transform; @st.cache_resource for the MongoDB client. This keeps UI snappy while avoiding redundant connections.

• Share card design
  Pillow + qrcode to render a social-ready PNG (1200×630) with title/date/caption overlay and a QR deep link.

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Limitations

• Rate limits: free NASA keys (and DEMO_KEY) may throttle; APOD/NeoWs/EONET calls include timeouts and user-facing errors. :contentReference[oaicite:13]{index=13}
• Data availability: some dates have videos (APOD) or no imagery (gallery queries) → UI handles fallbacks gracefully.
• Local QR links: on localhost, QR deep links are rewritten to LAN IP for phone testing; in Cloud they use the public URL.

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Roadmap

• Gallery favorites with tags/notes (Mongo).
• EONET cluster markers & time slider.
• NEOs: hazard filters, color-coded LD risk bands, mini charts.
• Optional EPIC “Blue Marble Today” page.

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License

This project is licensed under the MIT License. See the LICENSE file for details.

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Contact

For questions or feedback:

• LinkedIn: https://www.linkedin.com/in/brejesh-balakrishnan-7855051b9/
• GitHub: https://github.com/brej-29

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References

• NASA API Portal (APIs & key registration): https://api.nasa.gov/
• NASA Image & Video Library API (search & asset): example collection docs / Postman overview.
• EONET v3 (events, categories): https://eonet.gsfc.nasa.gov/docs/v3 and live categories endpoint.
• Asteroids NeoWs (feed, lookup, browse): dataset/API description. https://data.nasa.gov/dataset/asteroids-neows-api
• Streamlit secrets (secrets.toml & Cloud secrets): docs pages.