Russian scientists propose mission to "tag" dangerous asteroid
Published: 2008 June 27; updated: 2009 Oct. 2, Dec. 30; 2010 Jan. 11, May 21
Like a potential criminal tagged with a GPS bracelet, the Earth-threatening space rock could be fitted with a tracking device, helping to watch its orbital movement with unquestionable precision, Russian scientists said.
In 2008, a team of engineers at NPO Lavochkin proposed an unmanned mission, which could place a radio beacon on the surface of asteroid 2004 MN4 Apophis. The 350-meter space boulder, discovered in 2004, was expected to pass as close as 36,000 kilometers from Earth in 2029 and, according to some estimates, the gravitational pull of the planet could put it on a collision course with Earth in 2036. NPO Lavochkin's proposal was prepared for a Moscow conference, marking the 100th anniversary of the infamous Tunguska event of June 30, 1908, which is believed to be the largest space object hitting the Earth in modern history. Russian scientists argued that in order to rule out the possibility of Apophis colliding with the Earth, the space rock’s orbit should be tracked with an accuracy of dozens of meters. This could be achieved only with a transponder anchored to the asteroid, as even the most powerful radio-telescopes on Earth can not track such a small body precisely enough.
To accomplish the mission, NPO Lavochkin proposed to use the spacecraft platform, which the company developed for the Phobos-Grunt project. NPO Lavochkin representatives believed that the Phobos-Grunt satellite bus could be used with minimal modifications for the mission to Apophis. The proposed flight scenario targeted May 13, 2012, as its launch date and a rendezvous with the asteroid 330 days (or 11 months) later (on March 12, 2013). The authors of the report urged the inclusion of the Apophis mission into the Russian Federal Space Program, emphasizing the high international prestige of such project. (409)
Although the Apophis mission would rely on existing technology and require relatively modest funding, achieving the 2012 launch date would not be realistic, observers noted. According to sources familiar with the matter, at the time of the asteroid mission proposal, the much more technically challenging Phobos-Grunt project faced a delay to 2011. This Russia’s flagship planetary mission would have to be grounded to enable the launch to Apophis in 2012. Critics mostly dismissed the proposal for the Apophis mission as either a face-saving ploy to cancel Phobos-Grunt, or as another unachievable project in the advertised timeframe. On June 30, 2008, the Russian space agency, Roskosmos, released a statement clarifying the fact that the mission to Apophis was an "independent and separate" project and rejected claims about changing goals of the Phobos-Grunt mission.
Early planning for asteroid missions
Although a mission to Apophis in 2012 was never considered realistic, as late as May 2009, Russian scientists still kept this dangerous space rock on a short list of potential targets for exploration. However by that time, the launch date had been moved to a comfortably distant 2024. (365) The story of the Russian mission to Apophis had another bizarre twist in 2009. At the end of December, the head of the Russian space agency, Anatoly Perminov told the Voice of Russia radio station that a soon-to-be-held meeting of the agency's collegium would consider an asteroid threat behind closed doors. Perminov was obviously talking about one of many theoretical and very preliminary concepts routinely considered by the agency's officials in the process of forming the nation's long-term plans in space. However, those few imprecisely minted words were enough for the Western media to run sensational stories the next morning about Russia's "secret plan to save the Earth from an asteroid." Nevertheless, US Congressman Dana Rohrabacher, representing State of California, a major base of the US aerospace industry, took Perminov's interview seriously enough to promise lobbying for a joint US-Russian asteroid-deflection mission.
On a more serious note, a possible Russian exploratory mission to Apophis was mentioned again at a scientific seminar in Moscow in May 2010. Lev Zeleny, the head of Space Research Institute, IKI, was quoted in a Roskosmos press-release as saying that the Apophis probe was "being developed" at NPO Lavochkin.
At the beginning of 2010s, Apophis seemed to remain the most popular target among Russian proposals for asteroid missions. It was revealed by that time that the spacecraft heading to Apophis was envisioned as a two-part vehicle which would split after entering orbit around the asteroid. One component, known as Small Unoriented Artificial Satellite of Asteroid, MNISA, would serve as a radio-beacon for a 5-10-year mission to precisely measure Apophis' trajectory. Russian sources claimed that it would enable to improve the accuracy of asteroid's trajectory predictions by 10,000 to 100,000 times. This prognosis could extend all the way to 2036, when Apophis would have possibly its closest rendezvous with the Earth. To complete its mission, MNISA would be equipped with a radioactive source of power and a power storage battery. A trio of antennas evenly spread around the cylindrical body of the satellite would ensure that it was always in contact with ground control despite the lack of orientation system onboard.
In the meantime, the second component, based on the cruise stage of Phobos-Grunt spacecraft would conduct 2-3 remote-sensing and geological research mission from orbit and, possibly, from the surface of the asteroid.
Surviving the cut?
Following the disastrous launch of the Phobos-Grunt spacecraft, the mission to Apophis survived on the list of potential planetary targets with a possible launch date in the 2020s. Russian officials continued mentioning the mission, while a number of other previously advertised planetary projects, such as Mars-NET, Venera-D and Mercury-P, were canceled or pushed far into the future.
Even the most powerful telescopes on Earth could see 2004 MN4 Apophis only as a tiny speck of light (center). According to Russian scientists, a 350-meter space rock could hit the Earth in 2029 or 2036. A less known asteroid 2004 VD17 with an estimated diameter of 500 meters could threaten Earth in 2012. Credit: Osservatorio Astronomico Sormano
The Apophis spacecraft in launch configuration, as it was envisioned around 2010. Credit: NPO Lavochkin
Artist rendering of a proposed Russian radio beacon designed to ensure that asteroid Apophis would not be on a collision course with Earth in 2036. Copyright © 2012 Anatoly Zak
The mission to Apophis was to be based on the Phobos-Grunt project. Credit: NPO Lavochkin
A circa 2012 depiction of the Apophis cruise stage and the Fregat space tug. Credit: IKI