noao0206 — Comunicado científico

Digital Movie Shows Awesome Speed of Asteroid Close Approach

21 Agosto 2002

Students from Yale University used the WIYN 0.9-meter telescope at Kitt Peak National Observatory to capture a series of still images of asteroid 2002 NY40 on August 15-16, two nights before its close flyby of Earth.

These images have been turned into a short digital movie that clearly demonstrates the impressive speed of 2002 NY40 as seen from Earth over a period of about two hours.

Yale undergraduate student Brandy Heflin and graduate student Bing Zhao were at the 0.9-meter telescope on Kitt Peak conducting research on exotic binary stars when they decided to interrupt their work to observe this unique event. A consortium of universities took over operation of the 0.9-meter telescope from the National Science Foundation last March, in order to give their students more hands-on research time.

These unplanned observations reflect the exact reasons that the university partnership took over operational responsibility for the telescope,” said astronomer Charles Bailyn, Heflin and Zhao’s research mentor at Yale. “They took me a bit by surprise, but we want to encourage students to take the initiative, and they did a very nice job. There is also some real science to be gleaned from these observations, in terms of brightness fluctuations and the rotational period of the asteroid.

2002 NY40 crossed an area of the sky about equal to the full Moon during the time period of the movie, traveling northwest through the constellation Aquarius. Two nights later, during its closest approach to Earth, the asteroid was moving across the sky about 20 times faster.

Discovered on July 14, asteroid 2002 NY40 has an estimated diameter of 700 meters (0.43 miles). It passed safely by Earth on the night of August 17-18 at a distance of approximately 524,000 kilometers (326,000 miles), about 1.3 times the distance from Earth to the Moon.

For the sake of comparison, if a person were riding on the asteroid and looking back toward Earth during its close passage, our planet would have appeared nearly three times larger on the sky than the Moon does from Earth.

A long-exposure image of the asteroid taken at the WIYN 3.5-meter telescope on the night of August 17 by Hillary Mathis showed no obvious evidence that 2002 NY40 is a binary asteroid, a possibility being investigated by radio telescopes and other observatories.

The digital movie of 2002 NY40 was created by the staff of the Public Affairs & Educational Outreach department at the National Optical Astronomy Observatory (NOAO) in Tucson, AZ.


Participants in the 0.9-meter consortium include Indiana University, San Francisco State University, the University of Florida, Wesleyan University and four University of Wisconsin campuses

NOAO is operated by the Association of Universities for Research in Astronomy (AURA), Inc., under a cooperative agreement with the National Science Foundation. NOAO operates telescopes at Kitt Peak National Observatory near Tucson, AZ, and Cerro Tololo Inter-american Observatory near La Serena, Chile, and it is the U.S. partner in the International Gemini Observatory.

Más Información

More information about the Wisconsin-Indiana-Yale-NOAO (WIYN) consortium’s operation of the 0.9-meter telescope is available in NOAO Press Release 01-07.


Douglas Isbell
Public Information OfficerNational Optical Astronomy Observatory
Tel: 520/318-8214
Correo electrónico:

Jacqueline Weaver
Yale News Office
Tel: 203 /432-8555
Correo electrónico:

About the Release

Release No.:noao0206
Legacy ID:NOAO 02-06
Nombre:2002 NY40
Facility:WIYN 0.9-meter Telescope


Digital Movie Shows Awesome Speed of Asteroid Close Approach
Digital Movie Shows Awesome Speed of Asteroid Close Approach