question: Help me understand why we can't see stars in pictures taken from space.
comment: You can see lots of stars in pictures taken from space, that's all the Hubble Space Telescope does. You can see stars in pictures taken from the ISS, as long as the Earth isn't in the picture ([my favorite]( URL_0 )). The Earth is really bright, particularly during the day. Cameras, and eyes for that matter, can't image a really bright thing and a really dim thing at the same exposure. That's why when you look up during the day, you don't see stars. The stars are there, but the sky glow (the blue scattering) is brighter than the stars.
passages: Section::::Extrasolar planets.:View from more distant stars (10 ly – ).
  
  From 40 Eridani, 16 light years away, the Sun would be an average looking star of about apparent magnitude 3.3 in the constellation Serpens Caput. At this distance most of the stars nearest to us would be in different locations to those in our sky, including Alpha Centauri, Sirius, and Procyon.
   Most stars are actually relatively cool objects emitting much of their electromagnetic radiation in the visible or near-infrared part of the spectrum. Ultraviolet radiation is the signature of hotter objects, typically in the early and late stages of their evolution. In the Earth's sky seen in ultraviolet light, most stars would fade in prominence. Some very young massive stars and some very old stars and galaxies, growing hotter and producing higher-energy radiation near their birth or death, would be visible. Clouds of gas and dust would block the vision in many directions along the Milky Way.
   The visibility of astronomical objects is strongly affected by light pollution. Even a few hundred kilometers away from a metropolitan area where the sky can appear to be very dark, it is still the residual light pollution that sets the limit on the visibility of faint objects. For most people, these are likely to be the best observing conditions within their reach. Under such "typical" dark sky conditions, the naked eye can see stars with an apparent magnitude up to +6. Under perfect dark sky conditions where all light pollution is absent, stars as faint as +8 might be visible.
   Historically, optical astronomy, also called visible light astronomy, is the oldest form of astronomy. Images of observations were originally drawn by hand. In the late 19th century and most of the 20th century, images were made using photographic equipment. Modern images are made using digital detectors, particularly using charge-coupled devices (CCDs) and recorded on modern medium. Although visible light itself extends from approximately 4000 Å to 7000 Å (400 nm to 700 nm), that same equipment can be used to observe some near-ultraviolet and near-infrared radiation.
  
  Section::::Observational astronomy.:Ultraviolet astronomy.
   For observers on extrasolar planets, the constellations would differ depending on the distances involved. The view of outer space of exoplanets can be extrapolated from open source software such as Celestia or Stellarium, and it appears that due to parallax, distant stars change their position less than nearby ones. For alien observers, the Sun would be visible to the naked human eye only at distances below 20 – 27 parsec (60–90 ly). If the Sun were to be observed from another star, it would always appear on the opposite coordinates in the sky. Thus an observer located near a star with RA at 4 hr and declination −10 would see the Sun located at RA: 16 hr, dec: +10. A consequence of observing the universe from other stars is that stars that may appear bright in our own sky may appear dimmer in other skies and vice versa.
   BULLET::::- WISPR, is double solar telescope on the Parker Solar Probe designed to image the corona close to the Sun from space
  
  Section::::Other types of observation.
  
  Most solar observatories observe optically at visible, UV, and near infrared wavelengths, but other solar phenomena can be observed — albeit not from the Earth's surface due to the absorption of the atmosphere:
  
  BULLET::::- Solar X-ray astronomy, observations of the Sun in x-rays
  
  BULLET::::- Multi-spectral solar telescope array (MSSTA), a rocket launched payload of UV telescopes in the 1990s
  
  BULLET::::- Leoncito Astronomical Complex operated a submillimeter wavelength solar telescope.
   Section::::Specialized catalogues.:Proper motion catalogues.
  
  A common way of detecting nearby stars is to look for relatively high proper motions. Several catalogues exist, of which we'll mention a few. The Ross and Wolf catalogues pioneered the domain:
  
  Willem Jacob Luyten later produced a series of catalogues:
  
  L - Luyten, Proper motion stars and White dwarfs
  
  LFT – Luyten Five-Tenths catalogue
  
  LHS – Luyten Half-Second catalogue
  
  LTT – Luyten Two-Tenths catalogue
  
  NLTT – New Luyten Two-Tenths catalogue
  
  LPM – Luyten Proper-Motion catalogue
  
  Around the same time period, Henry Lee Giclas worked on a similar series of catalogues:
  
  Section::::Specialized catalogues.:uvby98.
   Since visible-light astronomy is restricted to only visible light, no equipment is necessary for simply star gazing. This means that it's the most commonly participated in type of astronomy, as well as the oldest.
  
  Section::::History.
  
  Section::::History.:Beginning.
  
  Before the advent of telescopes, astronomy was limited solely to unaided eyesight. Humans have been looking at stars and objects in the night sky for thousands of years, as is evident in the naming of many constellations, notably the largely Greek names used today. 
   Section::::Amateur astrophotography.:Hardware.:Equipment setups.
  
  BULLET::::- Fixed or tripod
   Seeing Stars
  
  Seeing Stars was the only album by the band Seeing Stars. It was essentially intended to be the fifth studio album by UK band All About Eve. In the aftermath of the "Ultraviolet" album's release – its bad reception and lost recording contract – whilst this album was being recorded in early 1993, lead singer Julianne Regan left the writing and recording session.
   BULLET::::- Stars vary far more in brightness than they do in distance.
  
  BULLET::::- Our line of sight through the Milky Way Galaxy is interrupted by great clouds of gas and dust, which block our view of stars more than a few thousand light-years away.
   Section::::Ultraviolet.
  
  Ultraviolet telescopes make observations at ultraviolet wavelengths, i.e. between approximately 10 and 320 nm. Light at these wavelengths is absorbed by the Earth's atmosphere, so observations at these wavelengths must be performed from the upper atmosphere or from space. Objects emitting ultraviolet radiation include the Sun, other stars and galaxies.
  
  UV ranges listed at Ultraviolet astronomy#Ultraviolet space telescopes.
  
  Section::::Visible light.
   Class M stars are by far the most common. About 76% of the main-sequence stars in the solar neighborhood are class M stars. However, class M main-sequence stars (red dwarfs) have such low luminosities that none are bright enough to be seen with the unaided eye, unless under exceptional conditions. The brightest known M-class main-sequence star is M0V Lacaille 8760, with magnitude 6.6 (the limiting magnitude for typical naked-eye visibility under good conditions is typically quoted as 6.5), and it is extremely unlikely that any brighter examples will be found.
   The first answer to this problem was speckle imaging, which allowed bright objects with simple morphology to be observed with diffraction-limited angular resolution. Later came NASA's Hubble Space Telescope, working outside the atmosphere and thus not having any seeing problems and allowing observations of faint targets for the first time (although with poorer resolution than speckle observations of bright sources from ground-based telescopes because of Hubble's smaller telescope diameter). The highest resolution visible and infrared images currently come from imaging optical interferometers such as the Navy Prototype Optical Interferometer or Cambridge Optical Aperture Synthesis Telescope, but those can only be used on very bright stars.
   It is expected that Pan-STARRS will discover an extremely large number of variable stars, including such stars in other nearby galaxies; in fact, this may lead to the discovery of hitherto unknown dwarf galaxies. In discovering a large number of Cepheid variables and eclipsing binary stars, it will help determine distances to nearby galaxies with greater precision. It is expected to discover a large number of Type Ia supernovae in other galaxies, which are important in studying the effects of dark energy, and also optical afterglows of gamma ray bursts.
   A star is an astronomical object consisting of a luminous spheroid of plasma held together by its own gravity. The nearest star to Earth is the Sun. Many other stars are visible to the naked eye from Earth during the night, appearing as a multitude of fixed luminous points in the sky due to their immense distance from Earth. Historically, the most prominent stars were grouped into constellations and asterisms, the brightest of which gained proper names. Astronomers have assembled star catalogues that identify the known stars and provide standardized stellar designations. However, most of the estimated 300 sextillion () stars in the observable universe are invisible to the naked eye from Earth, including all stars outside our galaxy, the Milky Way.
   Section::::Observation tools.:Photography.:Advantages.
  
  Prior to the invention of photography, all astronomy was done with the naked eye. However, even before films became sensitive enough, scientific astronomy moved entirely to film, because of the overwhelming advantages:
  
  BULLET::::- The human eye discards what it sees from split-second to split-second, but photographic film gathers more and more light for as long as the shutter is open.
  
  BULLET::::- The resulting image is permanent, so many astronomers can use the same data.
  
  BULLET::::- It is possible to see objects as they change over time (SN 1987A is a spectacular example).
  
  Section::::Observation tools.:Photography.:Blink comparator.
   Professional filters are also colored, but their bandpass centers are placed around other midpoints (such as in the UBVRI and Cousins systems).
  
  Some of common color filters and their uses are:
  
  BULLET::::- Chromatic aberration filters: Used for reduction of the purplish halo, caused by chromatic aberration of refracting telescopes. Such halo can obscure features of bright objects, especially Moon and planets. These filters have no effect on observing faint objects.
   Pan-STARRS will also measure proper motion and parallax and should thereby discover a large number of brown dwarfs and white dwarfs and other nearby faint objects, and it should be able to conduct a complete census of all stars within 100 parsecs of the Sun. Prior proper motion and parallax surveys often did not detect faint objects such as the recently discovered Teegarden's star, which are too faint for projects such as Hipparcos.
   The oldest form of astronomy, optical or visible-light astronomy, observes wavelengths of light from approximately 400 to 700 nm. Positioning an optical telescope in space eliminates the distortions and limitations that hamper that ground-based optical telescopes (see Astronomical seeing), providing higher resolution images. Optical telescopes are used to look at planets, stars, galaxies, planetary nebulae and protoplanetary disks, amongst many other things.
  
  Section::::Infrared and submillimetre.
   In some places (away from urban light pollution, moonlight, auroras, and other sources of light), where the sky is dark enough for nearly all astronomical observations, astronomers can easily make observations of point sources such as stars both during and after astronomical twilight in the evening and both before and during astronomical twilight in the morning. However, some critical observations, such as of faint diffuse items such as nebulae and galaxies, may require observation beyond the limit of astronomical twilight. Theoretically, the faintest stars detectable by the naked eye (those of approximately the sixth magnitude) will become visible in the evening at astronomical dusk, and become invisible at astronomical dawn.
   Visible-light astronomy has existed as long as people have been looking up at the night sky, although it has since improved in its observational capabilities since the invention of the telescope, which is commonly credited to Hans Lippershey, a German-Dutch spectacle-maker, although Galileo played a large role in the development and creation of telescopes. Visible-light astronomy continues to get better in the modern day, with projects such as the James Webb Telescope being projected for launch in the next few years.
   Astrophotography is a popular hobby among photographers and amateur astronomers. Images of the night sky can be obtained with the most basic film and digital cameras. For simple star trails, no additional equipment may be necessary other than common tripods. There is a wide range of commercial equipment geared toward basic and advanced astrophotography. Amateur astronomers and amateur telescope makers also use homemade equipment and modified devices.
  
  Section::::Amateur astrophotography.:Media.
   As an example, imaging instruments on the Hubble Space Telescope offer coronagraphic capability.
  
  Section::::Design.:Band-limited coronagraph.
  
  A "band-limited coronagraph" uses a special kind of mask called a "band-limited mask". This mask is designed to block light and also manage diffraction effects caused by removal of the light. The band-limited coronagraph has served as the baseline design for the canceled Terrestrial Planet Finder coronagraph. Band-limited masks will also be available on the James Webb Space Telescope.
  
  See also: 
  
  Section::::Design.:Phase-mask coronagraph.
   A cross screen filter, also known as a star filter, creates a star pattern, in which lines radiate outward from bright objects. The star pattern is generated by a very fine diffraction grating embedded in the filter, or sometimes by the use of prisms in the filter. The number of stars varies by the construction of the filter, as does the number of points each star has.
  
  Section::::Uses of filters in photography.:Diffusion.
  
presuppositions: You can't see stars in pictures taken from space. You can't see stars in pictures taken from space.
corrections: You can see lots of stars in pictures taken from space, such as through the Hubble Space Telescope. You can see lots of stars in pictures taken from space as long as the Earth is not in the picture.
raw_presuppositions: You can't see stars in pictures taken from space. You can't see stars in pictures taken from space.
raw_corrections: You can see lots of stars in pictures taken from space, such as through the Hubble Space Telescope. You can see lots of stars in pictures taken from space as long as the Earth is not in the picture.