Skip to main content
Log in

Almost Planet X

  • News & Views
  • Published:

From Nature

View current issue Submit your manuscript

Optical and infrared observations of a bright object in the outer Solar System reveal it to be surprisingly large — almost as big as Pluto's moon. It could be the first of many such discoveries.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Figure 1: The size and surface darkness of the ninth planet Pluto, its moon Charon, and the newly discovered object Varuna, the three largest known members of an ancient belt of icy objects that surround the eight planets closest to the Sun.

References

  1. Jewitt, D. & Luu, J. Nature 362, 730–732 (1993).

    Article  ADS  Google Scholar 

  2. http://cfa-www.harvard.edu/cfa/ps/lists/TNOs.html

  3. Jewitt, D., Aussel, H. & Evans, A. Nature 411, 446–447 (2001).

    Article  ADS  CAS  Google Scholar 

  4. McMillan, R. & Larsen, J. Minor Planet Electronic Circular 2000–X02 (Minor Planet Center, Cambridge, MA, 2000).

    Google Scholar 

  5. Leonard, F. C. Leaflet Astron. Soc. Pacific 1, 121–124 (1930).

    ADS  Google Scholar 

  6. Kuiper, G. P. in Astrophysics: A Topical Symposium (ed. Hynek, J.) 357–427 (McGraw-Hill, New York, 1951).

    Google Scholar 

  7. Edgeworth, K. E. J. Br. Astron. Assoc. 53, 181–188 (1943).

    ADS  Google Scholar 

  8. Jewitt, D. C. & Luu, J. X. in Protostars and Planets IV (eds Mannings, V., Boss, A. P. & Russell, S. S.) 1201–1229 (Arizona Univ. Press, Tucson, 2000).

    Google Scholar 

  9. Tholen, D. J. & Buie, M. W. in Pluto and Charon (eds Stern, S. A. & Tholen, D. J.) 193–219 (Arizona Univ. Press, Tucson, 1997).

    Google Scholar 

  10. Marcialis, R. L., Rieke, G. H. & Lebofsky, L. A. Science 237, 1349–1351 (1987).

    Article  ADS  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Tegler, S., Romanishin, W. Almost Planet X. Nature 411, 423–424 (2001). https://doi.org/10.1038/35078164

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1038/35078164

  • Springer Nature Limited

Navigation