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   "source": [
    "# Quickstart"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "If you have a working version of Python installed on your system, it is easy to install Lightkurve and its dependencies using the ``pip`` package manager.  In a terminal window or Jupyter notebook cell, type:\n",
    "```\n",
    "! python -m pip install lightkurve --upgrade\n",
    "```\n",
    "\n",
    "See our [installation instructions](about/install.rst) page for details and troubleshooting information.\n",
    "\n",
    "With Lightkurve installed, it is easy to extract brightness time series data (astronomers call this a *light curve*)\n",
    "from the tiny images of stars collected by NASA's Kepler and TESS planet-hunting telescopes.\n",
    "\n",
    "For example, let's download and display the pixels of a famous star named [KIC 8462852](https://en.wikipedia.org/wiki/KIC_8462852), also known as *Tabby's Star* or *Boyajian's Star*, which is known to show unusual light fluctuations.\n",
    "\n",
    "First, we start Python and use the `search_targetpixelfile` function to obtain the Kepler pixel data for the star  from the [data archive](https://archive.stsci.edu/kepler/):"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "from lightkurve import search_targetpixelfile\n",
    "pixelfile = search_targetpixelfile(\"KIC 8462852\", quarter=16).download();"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Next, let's display the first image in this data set:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "pixelfile.plot(frame=1);"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "It looks like the star is an isolated object, so we can extract a light curve by simply summing up all the pixel values in each image:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "lc = pixelfile.to_lightcurve(aperture_mask='all');"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "The above method returned a `LightCurve` object which gives us access to the number of photons received by the spacecraft over time (known as the *flux*).  The time is an [AstroPy Time object](https://docs.astropy.org/en/stable/time/) in units of *days*:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "lc.time"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "The flux is an [AstroPy Quantity object](https://docs.astropy.org/en/stable/units/) in units *electrons/second*:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "lc.flux"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "We can plot these data using the `plot()` method:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "lc.plot();"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "The plot reveals a short-lived 20% dip in the brightness of the star.  It looks like we re-discovered one of the [intriguing dips in Tabby's star](https://en.wikipedia.org/wiki/KIC_8462852#Luminosity).\n",
    "\n",
    "Congratulations, you are now able to make new discoveries in Kepler and TESS data!\n",
    "\n",
    "Next, head to our [tutorials section](https://docs.lightkurve.org/tutorials) to be guided through more detailed examples of carrying out science with Lightkurve!"
   ]
  }
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