EntityQ1867641· pop 9· linked from 276 articlesLockman HoleSign in to savearea of sky useful for deep space observations due to low levels of neutral hydrogen gasConnectionshydrogenEntityMilky WayEntityBlack holeConceptchemical elementEntitygalaxyEntitymoleculeEntityskyEntitygasEntityconstellationEntityX-rayEntityUrsa MajorEntityinfrared radiationEntityphotonEntitydigital object identifierEntityradiationEntitydiffusionEntityelectronvoltEntityinterstellar mediumEntitydeclinationEntityright ascensionEntityCategoriesInterstellar mediaObservational astronomyUrsa MajorX-ray astronomy