A balloon-borne telescope is a type of

airborne telescope An airborne observatory is an airplane, airship, or research balloon, balloon with an astronomical telescope. By carrying the telescope to a sufficiently high altitude, the telescope can avoid cloud cover, pollution, and carry out Observational a ...

, a sub-orbital

astronomical telescope A telescope is a device used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. Originally meaning only an optical instrument using lenses, curved mirrors, or a combination of both to obse ...

that is suspended below one or more

stratospheric The stratosphere () is the second layer of the atmosphere of the Earth, located above the troposphere and below the mesosphere. The stratosphere is an atmospheric layer composed of stratified temperature layers, with the warm layers of air hi ...

balloons, allowing it to be lifted above the lower, dense part of the

Earth's atmosphere The atmosphere of Earth is the layer of gases, known collectively as air, retained by Earth's gravity that surrounds the planet and forms its planetary atmosphere. The atmosphere of Earth protects life on Earth by creating pressure allowing f ...

. This has the advantage of improving the resolution limit of the telescope at a much lower cost than for a

space telescope A space telescope or space observatory is a telescope in outer space used to observe astronomical objects. Suggested by Lyman Spitzer in 1946, the first operational telescopes were the American Orbiting Astronomical Observatory, OAO-2 launch ...

. It also allows observation of frequency bands that are blocked by the atmosphere. Balloon-borne telescopes have the disadvantage of relatively low altitude and a flight time of only a few days. However, their maximum altitude of about 50 km is much higher than the limiting altitude of aircraft-borne telescopes such as the

Kuiper Airborne Observatory The Gerard P. Kuiper Airborne Observatory (KAO) was a national facility operated by NASA to support research in infrared astronomy. The observation platform was a highly modified Lockheed C-141A Starlifter jet transport aircraft (s/n: 6110, reg ...

and

Stratospheric Observatory for Infrared Astronomy The Stratospheric Observatory for Infrared Astronomy (SOFIA) was an 80/20 joint project of NASA and the German Aerospace Center (DLR) to construct and maintain an airborne observatory. NASA awarded the contract for the development of the aircra ...

, which have a limiting altitude of 15 km. A few balloon-borne telescopes have crash landed, resulting in damage to, or destruction of the telescope. The balloon obscures the zenith from the telescope, but a very long suspension can reduce this to a range of 2°. The telescope must be isolated from the induced motion of the

winds as well as the slow rotation and

pendulum A pendulum is a weight suspended from a wikt:pivot, pivot so that it can swing freely. When a pendulum is displaced sideways from its resting, Mechanical equilibrium, equilibrium position, it is subject to a restoring force due to gravity that ...

motion of the balloon. The azimuth stability can be maintained by a

magnetometer A magnetometer is a device that measures magnetic field or magnetic dipole moment. Different types of magnetometers measure the direction, strength, or relative change of a magnetic field at a particular location. A compass is one such device, o ...

, plus a gyroscope or star tracker for shorter term corrections. A three axis mount gives the best control over the tube motion, consisting of an azimuth, elevation and cross-elevation axis.

Missions

References

{{reflist, colwidth=30em, refs= {{cite book , first=Christopher R. , last=Kitchin , year=2003 , page=83 , title=Astrophysical techniques , edition=4th , publisher=

CRC Press The CRC Press, LLC is an American publishing group that specializes in producing technical books. Many of their books relate to engineering, science and mathematics. Their scope also includes books on business, forensics and information tec ...

, isbn=0-7503-0946-6 {{cite journal , first=Stephen , last=Kidd , title=Astronomical ballooning: the Stratoscope program , journal=New Scientist , volume=23 , issue=409 , date=September 17, 1964 , pages=702–704 , url=https://books.google.com/books?id=3qpBF3BjFE4C&pg=PA702 , accessdate=2011-02-28 {{cite web , first=Mark , last=Devlin , work=blastexperiment , title=Balloon-borne Large-Aperture Submillimeter Telescope: home page , url=http://blastexperiment.info/ , accessdate=2011-02-28 , archive-url=https://web.archive.org/web/20110603211103/http://blastexperiment.info/ , archive-date=2011-06-03 , url-status=dead {{cite journal , last=Masi , first=S. , title=The BOOMERanG experiment and the curvature of the universe , journal=Progress in Particle and Nuclear Physics , volume=48 , issue=1 , pages=243–261 , year=2002 , doi=10.1016/S0146-6410(02)00131-X , bibcode=2002PrPNP..48..243M , arxiv = astro-ph/0201137 , s2cid=16998444 {{cite journal , last=Tueller , first=J. , title=InFOCμS hard X-ray imaging telescope , year=2005 , journal=Experimental Astronomy , volume=20 , issue=1–3 , pages=121–129 , doi=10.1007/s10686-006-9028-3 , bibcode = 2005ExA....20..121T , s2cid=122127514 , url=https://zenodo.org/record/1232802 , display-authors=etal {{cite journal , last=Schmidt , first=W. , title=SUNRISE Impressions from a successful science flight , journal=Astronomische Nachrichten , volume=331 , issue=6 , page=601 , date=June 2010 , doi=10.1002/asna.201011383 , bibcode=2010AN....331..601S , display-authors=etal {{cite journal , title=MAXIMA: A balloon-borne cosmic microwave background anisotropy experiment , last=Rabii , first=B. , journal=Review of Scientific Instruments , volume=77 , issue=7 , date=July 2006 , doi=10.1063/1.2219723 , bibcode=2006RScI...77g1101R , arxiv = astro-ph/0309414 , display-authors=etal , page=071101, s2cid=16803721 {{cite web , first=Tariq , last=Malik , date=April 29, 2010 , work=space.com , title=Huge NASA Science Balloon Crashes in Australian Outback , url=http://www.space.com/8311-huge-nasa-science-balloon-crashes-australian-outback.html , accessdate=2011-02-28 {{cite book , first=Jingquan , last=Cheng , year=2009 , pages=509–510 , title=The principles of astronomical telescope design , volume=360 , series=Astrophysics and space science library , publisher=Springer , isbn=978-0-387-88790-6 {{cite book , first=Robert , last=Zimmerman , year=2010 , page=18 , title=The universe in a mirror: the saga of the Hubble Telescope and the visionaries who built it , publisher=

Princeton University Press Princeton University Press is an independent Academic publishing, publisher with close connections to Princeton University. Its mission is to disseminate scholarship within academia and society at large. The press was founded by Whitney Darrow, ...

, isbn=978-0-691-14635-5 {{cite journal , title=In-flight Performance of the Balloon-borne High Energy Focusing Telescope , author=Chen, C. M. Hubert , journal=Bulletin of the American Astronomical Society , volume=38 , page=383 , date=September 2006 , bibcode=2006HEAD....9.1812C , display-authors=etal {{cite journal , last1=Hofmann , first1=W. , last2=Lemke , first2=D. , last3=Thum , first3=C. , title=Surface brightness of the central region of the Milky Way at 2.4 and 3.4 microns , journal=Astronomy and Astrophysics , volume=57 , issue=1–2 , pages=111–114 , date=May 1977 , bibcode=1977A&A....57..111H {{cite journal , author=Boggs, S. E. , title=Balloon flight test of pulse shape discrimination (PSD) electronics and background model performance on the HIREGS payload , journal=Nuclear Instruments and Methods in Physics Research Section A , volume=491 , issue=3 , pages=390–401 , date=October 2002 , doi=10.1016/S0168-9002(02)01228-7 , bibcode=2002NIMPA.491..390B , display-authors=etal {{cite web, title=PoGOLite: home page , url=http://www.particle.kth.se/pogolite/ , accessdate=2015-06-11 , url-status=dead , archiveurl=https://web.archive.org/web/20140420201931/http://www.particle.kth.se/pogolite/ , archivedate=2014-04-20 {{cite journal , last1=Crill , first1=B.P. , last2=Ade , first2=P.A.R , last3=Battistelli , first3=E.S. , editor-first1=Jacobus M , editor-first2=Mattheus W. M , editor-first3=Howard A , editor-last1=Oschmann, Jr , editor-last2=De Graauw , editor-last3=MacEwen , title=SPIDER: a balloon-borne large-scale CMB polarimeter , journal=Space Telescopes and Instrumentation 2008: Optical, Infrared, and Millimeter , publisher=SPIE , year=2008 , volume=7010 , pages=70102P , doi=10.1117/12.787446 , arxiv=0807.1548 , bibcode=2008SPIE.7010E..2PC , s2cid=7924096 * Telescope types

Missions

See also

References